Statistical Power in Longitudinal Network Studies

NARCIS (Netherlands)

Stadtfeld, Christoph; Snijders, Tom A. B.; Steglich, Christian; van Duijn, Marijtje

2018-01-01

Longitudinal social network studies may easily suffer from a lack of statistical power. This is the case in particular for studies that simultaneously investigate change of network ties and change of nodal attributes. Such selection and influence studies have become increasingly popular due to the

Aortic insufficiency

Science.gov (United States)

... page, please enable JavaScript. Aortic insufficiency is a heart valve disease in which the aortic valve does not close ... aortic insufficiency Images Aortic insufficiency References Carabello BA. Valvular heart disease. In: Goldman L, Schafer AI, eds. Goldman-Cecil ...

Statistical Analysis of the Impact of Wind Power on Market Quantities and Power Flows

DEFF Research Database (Denmark)

Pinson, Pierre; Jónsson, Tryggvi; Zugno, Marco

2012-01-01

In view of the increasing penetration of wind power in a number of power systems and markets worldwide, we discuss some of the impacts that wind energy may have on market quantities and cross-border power flows. These impacts are uncovered through statistical analyses of actual market and flow data...... of load and wind power forecasts on Danish and German electricity markets....

Statistical operation of nuclear power plants

International Nuclear Information System (INIS)

Gauzit, Maurice; Wilmart, Yves

1976-01-01

A comparison of the statistical operating results of nuclear power stations as issued in the literature shows that the values given for availability and the load factor often differ considerably from each other. This may be due to different definitions given to these terms or even to a poor translation from one language into another. A critical analysis of these terms as well as the choice of a parameter from which it is possible to have a quantitative idea of the actual quality of the operation obtained is proposed. The second section gives, on an homogenous basis and from the results supplied by 83 nuclear power stations now in operation, a statistical analysis of their operating results: in particular, the two light water lines, during 1975, as well as the evolution in terms of age, of the units or the starting conditions of the units during their first two operating years. Test values thus obtained are compared also to those taken 'a priori' as hypothesis in some economic studies [fr

Statistical studies of powerful extragalactic radio sources

Energy Technology Data Exchange (ETDEWEB)

Macklin, J T

1981-01-01

This dissertation is mainly about the use of efficient statistical tests to study the properties of powerful extragalactic radio sources. Most of the analysis is based on subsets of a sample of 166 bright (3CR) sources selected at 178 MHz. The first chapter is introductory and it is followed by three on the misalignment and symmetry of double radio sources. The properties of nuclear components in extragalactic sources are discussed in the next chapter, using statistical tests which make efficient use of upper limits, often the only available information on the flux density from the nuclear component. Multifrequency observations of four 3CR sources are presented in the next chapter. The penultimate chapter is about the analysis of correlations involving more than two variables. The Spearman partial rank correlation coefficient is shown to be the most powerful test available which is based on non-parametric statistics. It is therefore used to study the dependences of the properties of sources on their size at constant redshift, and the results are interpreted in terms of source evolution. Correlations of source properties with luminosity and redshift are then examined.

Low statistical power in biomedical science: a review of three human research domains

Science.gov (United States)

Dumas-Mallet, Estelle; Button, Katherine S.; Boraud, Thomas; Gonon, Francois

2017-01-01

Studies with low statistical power increase the likelihood that a statistically significant finding represents a false positive result. We conducted a review of meta-analyses of studies investigating the association of biological, environmental or cognitive parameters with neurological, psychiatric and somatic diseases, excluding treatment studies, in order to estimate the average statistical power across these domains. Taking the effect size indicated by a meta-analysis as the best estimate of the likely true effect size, and assuming a threshold for declaring statistical significance of 5%, we found that approximately 50% of studies have statistical power in the 0–10% or 11–20% range, well below the minimum of 80% that is often considered conventional. Studies with low statistical power appear to be common in the biomedical sciences, at least in the specific subject areas captured by our search strategy. However, we also observe evidence that this depends in part on research methodology, with candidate gene studies showing very low average power and studies using cognitive/behavioural measures showing high average power. This warrants further investigation. PMID:28386409

Statistical modelling of space-time processes with application to wind power

DEFF Research Database (Denmark)

Lenzi, Amanda

. This thesis aims at contributing to the wind power literature by building and evaluating new statistical techniques for producing forecasts at multiple locations and lead times using spatio-temporal information. By exploring the features of a rich portfolio of wind farms in western Denmark, we investigate...... propose spatial models for predicting wind power generation at two different time scales: for annual average wind power generation and for a high temporal resolution (typically wind power averages over 15-min time steps). In both cases, we use a spatial hierarchical statistical model in which spatial...

Impact of statistical learning methods on the predictive power of multivariate normal tissue complication probability models.

Science.gov (United States)

Xu, Cheng-Jian; van der Schaaf, Arjen; Schilstra, Cornelis; Langendijk, Johannes A; van't Veld, Aart A

2012-03-15

To study the impact of different statistical learning methods on the prediction performance of multivariate normal tissue complication probability (NTCP) models. In this study, three learning methods, stepwise selection, least absolute shrinkage and selection operator (LASSO), and Bayesian model averaging (BMA), were used to build NTCP models of xerostomia following radiotherapy treatment for head and neck cancer. Performance of each learning method was evaluated by a repeated cross-validation scheme in order to obtain a fair comparison among methods. It was found that the LASSO and BMA methods produced models with significantly better predictive power than that of the stepwise selection method. Furthermore, the LASSO method yields an easily interpretable model as the stepwise method does, in contrast to the less intuitive BMA method. The commonly used stepwise selection method, which is simple to execute, may be insufficient for NTCP modeling. The LASSO method is recommended. Copyright © 2012 Elsevier Inc. All rights reserved.

Impact of Statistical Learning Methods on the Predictive Power of Multivariate Normal Tissue Complication Probability Models

Energy Technology Data Exchange (ETDEWEB)

Xu Chengjian, E-mail: c.j.xu@umcg.nl [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Schaaf, Arjen van der; Schilstra, Cornelis; Langendijk, Johannes A.; Veld, Aart A. van' t [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands)

2012-03-15

Purpose: To study the impact of different statistical learning methods on the prediction performance of multivariate normal tissue complication probability (NTCP) models. Methods and Materials: In this study, three learning methods, stepwise selection, least absolute shrinkage and selection operator (LASSO), and Bayesian model averaging (BMA), were used to build NTCP models of xerostomia following radiotherapy treatment for head and neck cancer. Performance of each learning method was evaluated by a repeated cross-validation scheme in order to obtain a fair comparison among methods. Results: It was found that the LASSO and BMA methods produced models with significantly better predictive power than that of the stepwise selection method. Furthermore, the LASSO method yields an easily interpretable model as the stepwise method does, in contrast to the less intuitive BMA method. Conclusions: The commonly used stepwise selection method, which is simple to execute, may be insufficient for NTCP modeling. The LASSO method is recommended.

Impact of Statistical Learning Methods on the Predictive Power of Multivariate Normal Tissue Complication Probability Models

International Nuclear Information System (INIS)

Xu Chengjian; Schaaf, Arjen van der; Schilstra, Cornelis; Langendijk, Johannes A.; Veld, Aart A. van’t

2012-01-01

Purpose: To study the impact of different statistical learning methods on the prediction performance of multivariate normal tissue complication probability (NTCP) models. Methods and Materials: In this study, three learning methods, stepwise selection, least absolute shrinkage and selection operator (LASSO), and Bayesian model averaging (BMA), were used to build NTCP models of xerostomia following radiotherapy treatment for head and neck cancer. Performance of each learning method was evaluated by a repeated cross-validation scheme in order to obtain a fair comparison among methods. Results: It was found that the LASSO and BMA methods produced models with significantly better predictive power than that of the stepwise selection method. Furthermore, the LASSO method yields an easily interpretable model as the stepwise method does, in contrast to the less intuitive BMA method. Conclusions: The commonly used stepwise selection method, which is simple to execute, may be insufficient for NTCP modeling. The LASSO method is recommended.

Recurrent Tricuspid Insufficiency

Science.gov (United States)

Kara, Ibrahim; Koksal, Cengiz; Cakalagaoglu, Canturk; Sahin, Muslum; Yanartas, Mehmet; Ay, Yasin; Demir, Serdar

2013-01-01

This study compares the medium-term results of De Vega, modified De Vega, and ring annuloplasty techniques for the correction of tricuspid insufficiency and investigates the risk factors for recurrent grades 3 and 4 tricuspid insufficiency after repair. In our clinic, 93 patients with functional tricuspid insufficiency underwent surgical tricuspid repair from May 2007 through October 2010. The study was retrospective, and all the data pertaining to the patients were retrieved from hospital records. Functional capacity, recurrent tricuspid insufficiency, and risk factors aggravating the insufficiency were analyzed for each patient. In the medium term (25.4 ± 10.3 mo), the rates of grades 3 and 4 tricuspid insufficiency in the De Vega, modified De Vega, and ring annuloplasty groups were 31%, 23.1%, and 6.1%, respectively. Logistic regression analysis revealed that chronic obstructive pulmonary disease, left ventricular dysfunction (ejection fraction, tricuspid insufficiency. Medium-term survival was 90.6% for the De Vega group, 96.3% for the modified De Vega group, and 97.1% for the ring annuloplasty group. Ring annuloplasty provided the best relief from recurrent tricuspid insufficiency when compared with DeVega annuloplasty. Modified De Vega annuloplasty might be a suitable alternative to ring annuloplasty when rings are not available. PMID:23466680

The issue of statistical power for overall model fit in evaluating structural equation models

Directory of Open Access Journals (Sweden)

Richard HERMIDA

2015-06-01

Full Text Available Statistical power is an important concept for psychological research. However, examining the power of a structural equation model (SEM is rare in practice. This article provides an accessible review of the concept of statistical power for the Root Mean Square Error of Approximation (RMSEA index of overall model fit in structural equation modeling. By way of example, we examine the current state of power in the literature by reviewing studies in top Industrial-Organizational (I/O Psychology journals using SEMs. Results indicate that in many studies, power is very low, which implies acceptance of invalid models. Additionally, we examined methodological situations which may have an influence on statistical power of SEMs. Results showed that power varies significantly as a function of model type and whether or not the model is the main model for the study. Finally, results indicated that power is significantly related to model fit statistics used in evaluating SEMs. The results from this quantitative review imply that researchers should be more vigilant with respect to power in structural equation modeling. We therefore conclude by offering methodological best practices to increase confidence in the interpretation of structural equation modeling results with respect to statistical power issues.

The relation between statistical power and inference in fMRI.

Directory of Open Access Journals (Sweden)

Henk R Cremers

Full Text Available Statistically underpowered studies can result in experimental failure even when all other experimental considerations have been addressed impeccably. In fMRI the combination of a large number of dependent variables, a relatively small number of observations (subjects, and a need to correct for multiple comparisons can decrease statistical power dramatically. This problem has been clearly addressed yet remains controversial-especially in regards to the expected effect sizes in fMRI, and especially for between-subjects effects such as group comparisons and brain-behavior correlations. We aimed to clarify the power problem by considering and contrasting two simulated scenarios of such possible brain-behavior correlations: weak diffuse effects and strong localized effects. Sampling from these scenarios shows that, particularly in the weak diffuse scenario, common sample sizes (n = 20-30 display extremely low statistical power, poorly represent the actual effects in the full sample, and show large variation on subsequent replications. Empirical data from the Human Connectome Project resembles the weak diffuse scenario much more than the localized strong scenario, which underscores the extent of the power problem for many studies. Possible solutions to the power problem include increasing the sample size, using less stringent thresholds, or focusing on a region-of-interest. However, these approaches are not always feasible and some have major drawbacks. The most prominent solutions that may help address the power problem include model-based (multivariate prediction methods and meta-analyses with related synthesis-oriented approaches.

Statistic method of research reactors maximum permissible power calculation

International Nuclear Information System (INIS)

Grosheva, N.A.; Kirsanov, G.A.; Konoplev, K.A.; Chmshkyan, D.V.

1998-01-01

The technique for calculating maximum permissible power of a research reactor at which the probability of the thermal-process accident does not exceed the specified value, is presented. The statistical method is used for the calculations. It is regarded that the determining function related to the reactor safety is the known function of the reactor power and many statistically independent values which list includes the reactor process parameters, geometrical characteristics of the reactor core and fuel elements, as well as random factors connected with the reactor specific features. Heat flux density or temperature is taken as a limiting factor. The program realization of the method discussed is briefly described. The results of calculating the PIK reactor margin coefficients for different probabilities of the thermal-process accident are considered as an example. It is shown that the probability of an accident with fuel element melting in hot zone is lower than 10 -8 1 per year for the reactor rated power [ru

Monte Carlo based statistical power analysis for mediation models: methods and software.

Science.gov (United States)

Zhang, Zhiyong

2014-12-01

The existing literature on statistical power analysis for mediation models often assumes data normality and is based on a less powerful Sobel test instead of the more powerful bootstrap test. This study proposes to estimate statistical power to detect mediation effects on the basis of the bootstrap method through Monte Carlo simulation. Nonnormal data with excessive skewness and kurtosis are allowed in the proposed method. A free R package called bmem is developed to conduct the power analysis discussed in this study. Four examples, including a simple mediation model, a multiple-mediator model with a latent mediator, a multiple-group mediation model, and a longitudinal mediation model, are provided to illustrate the proposed method.

Statistical power as a function of Cronbach alpha of instrument questionnaire items.

Science.gov (United States)

Heo, Moonseong; Kim, Namhee; Faith, Myles S

2015-10-14

In countless number of clinical trials, measurements of outcomes rely on instrument questionnaire items which however often suffer measurement error problems which in turn affect statistical power of study designs. The Cronbach alpha or coefficient alpha, here denoted by C(α), can be used as a measure of internal consistency of parallel instrument items that are developed to measure a target unidimensional outcome construct. Scale score for the target construct is often represented by the sum of the item scores. However, power functions based on C(α) have been lacking for various study designs. We formulate a statistical model for parallel items to derive power functions as a function of C(α) under several study designs. To this end, we assume fixed true score variance assumption as opposed to usual fixed total variance assumption. That assumption is critical and practically relevant to show that smaller measurement errors are inversely associated with higher inter-item correlations, and thus that greater C(α) is associated with greater statistical power. We compare the derived theoretical statistical power with empirical power obtained through Monte Carlo simulations for the following comparisons: one-sample comparison of pre- and post-treatment mean differences, two-sample comparison of pre-post mean differences between groups, and two-sample comparison of mean differences between groups. It is shown that C(α) is the same as a test-retest correlation of the scale scores of parallel items, which enables testing significance of C(α). Closed-form power functions and samples size determination formulas are derived in terms of C(α), for all of the aforementioned comparisons. Power functions are shown to be an increasing function of C(α), regardless of comparison of interest. The derived power functions are well validated by simulation studies that show that the magnitudes of theoretical power are virtually identical to those of the empirical power. Regardless

GWAPower: a statistical power calculation software for genome-wide association studies with quantitative traits.

Science.gov (United States)

Feng, Sheng; Wang, Shengchu; Chen, Chia-Cheng; Lan, Lan

2011-01-21

In designing genome-wide association (GWA) studies it is important to calculate statistical power. General statistical power calculation procedures for quantitative measures often require information concerning summary statistics of distributions such as mean and variance. However, with genetic studies, the effect size of quantitative traits is traditionally expressed as heritability, a quantity defined as the amount of phenotypic variation in the population that can be ascribed to the genetic variants among individuals. Heritability is hard to transform into summary statistics. Therefore, general power calculation procedures cannot be used directly in GWA studies. The development of appropriate statistical methods and a user-friendly software package to address this problem would be welcomed. This paper presents GWAPower, a statistical software package of power calculation designed for GWA studies with quantitative traits, where genetic effect is defined as heritability. Based on several popular one-degree-of-freedom genetic models, this method avoids the need to specify the non-centrality parameter of the F-distribution under the alternative hypothesis. Therefore, it can use heritability information directly without approximation. In GWAPower, the power calculation can be easily adjusted for adding covariates and linkage disequilibrium information. An example is provided to illustrate GWAPower, followed by discussions. GWAPower is a user-friendly free software package for calculating statistical power based on heritability in GWA studies with quantitative traits. The software is freely available at: http://dl.dropbox.com/u/10502931/GWAPower.zip.

Imaging of insufficiency fractures

Energy Technology Data Exchange (ETDEWEB)

Krestan, Christian [Department of Radiology, Medical University of Vienna, Vienna General Hospital, Waehringerstr. 18-20, 1090 Vienna (Austria)], E-mail: christian.krestan@meduniwien.ac.at; Hojreh, Azadeh [Department of Radiology, Medical University of Vienna, Vienna General Hospital, Waehringerstr. 18-20, 1090 Vienna (Austria)

2009-09-15

This review focuses on the occurrence, imaging and differential diagnosis of insufficiency fractures. Prevalence, the most common sites of insufficiency fractures and their clinical implications are discussed. Insufficiency fractures occur with normal stress exerted on weakened bone. Postmenopausal osteoporosis is the most common cause of insufficiency fractures. Other conditions which affect bone turnover include osteomalacia, hyperparathyroidism, chronic renal failure and high-dose glucocorticoid therapy. It is a challenge for the radiologist to detect and diagnose insufficiency fractures, and to differentiate them from other bone lesions. Radiographs are still the most widely used imaging method for identification of insufficiency fractures, but sensitivity is limited, depending on the location of the fractures. Magnetic resonance imaging (MRI) is a very sensitive tool to visualize bone marrow abnormalities associated with insufficiency fractures. Thin section, multi-detector computed tomography (MDCT) depicts subtle fracture lines allowing direct visualization of cortical and trabecular bone. Bone scintigraphy still plays a role in detecting fractures, with good sensitivity but limited specificity. The most important differential diagnosis is underlying malignant disease leading to pathologic fractures. Bone densitometry and clinical history may also be helpful in confirming the diagnosis of insufficiency fractures.

Forecasting winds over nuclear power plants statistics

International Nuclear Information System (INIS)

Marais, Ch.

1997-01-01

In the event of an accident at nuclear power plant, it is essential to forecast the wind velocity at the level where the efflux occurs (about 100 m). At present meteorologists refine the wind forecast from the coarse grid of numerical weather prediction (NWP) models. The purpose of this study is to improve the forecasts by developing a statistical adaptation method which corrects the NWP forecasts by using statistical comparisons between wind forecasts and observations. The Multiple Linear Regression method is used here to forecast the 100 m wind at 12 and 24 hours range for three Electricite de France (EDF) sites. It turns out that this approach gives better forecasts than the NWP model alone and is worthy of operational use. (author)

Causality in Statistical Power: Isomorphic Properties of Measurement, Research Design, Effect Size, and Sample Size

Directory of Open Access Journals (Sweden)

R. Eric Heidel

2016-01-01

Full Text Available Statistical power is the ability to detect a significant effect, given that the effect actually exists in a population. Like most statistical concepts, statistical power tends to induce cognitive dissonance in hepatology researchers. However, planning for statistical power by an a priori sample size calculation is of paramount importance when designing a research study. There are five specific empirical components that make up an a priori sample size calculation: the scale of measurement of the outcome, the research design, the magnitude of the effect size, the variance of the effect size, and the sample size. A framework grounded in the phenomenon of isomorphism, or interdependencies amongst different constructs with similar forms, will be presented to understand the isomorphic effects of decisions made on each of the five aforementioned components of statistical power.

Statistical power analyses using G*Power 3.1: tests for correlation and regression analyses.

Science.gov (United States)

Faul, Franz; Erdfelder, Edgar; Buchner, Axel; Lang, Albert-Georg

2009-11-01

G*Power is a free power analysis program for a variety of statistical tests. We present extensions and improvements of the version introduced by Faul, Erdfelder, Lang, and Buchner (2007) in the domain of correlation and regression analyses. In the new version, we have added procedures to analyze the power of tests based on (1) single-sample tetrachoric correlations, (2) comparisons of dependent correlations, (3) bivariate linear regression, (4) multiple linear regression based on the random predictor model, (5) logistic regression, and (6) Poisson regression. We describe these new features and provide a brief introduction to their scope and handling.

Statistical power of model selection strategies for genome-wide association studies.

Directory of Open Access Journals (Sweden)

Zheyang Wu

2009-07-01

Full Text Available Genome-wide association studies (GWAS aim to identify genetic variants related to diseases by examining the associations between phenotypes and hundreds of thousands of genotyped markers. Because many genes are potentially involved in common diseases and a large number of markers are analyzed, it is crucial to devise an effective strategy to identify truly associated variants that have individual and/or interactive effects, while controlling false positives at the desired level. Although a number of model selection methods have been proposed in the literature, including marginal search, exhaustive search, and forward search, their relative performance has only been evaluated through limited simulations due to the lack of an analytical approach to calculating the power of these methods. This article develops a novel statistical approach for power calculation, derives accurate formulas for the power of different model selection strategies, and then uses the formulas to evaluate and compare these strategies in genetic model spaces. In contrast to previous studies, our theoretical framework allows for random genotypes, correlations among test statistics, and a false-positive control based on GWAS practice. After the accuracy of our analytical results is validated through simulations, they are utilized to systematically evaluate and compare the performance of these strategies in a wide class of genetic models. For a specific genetic model, our results clearly reveal how different factors, such as effect size, allele frequency, and interaction, jointly affect the statistical power of each strategy. An example is provided for the application of our approach to empirical research. The statistical approach used in our derivations is general and can be employed to address the model selection problems in other random predictor settings. We have developed an R package markerSearchPower to implement our formulas, which can be downloaded from the

Power generation statistics

International Nuclear Information System (INIS)

Kangas, H.

2001-01-01

The frost in February increased the power demand in Finland significantly. The total power consumption in Finland during January-February 2001 was about 4% higher than a year before. In January 2001 the average temperature in Finland was only about - 4 deg C, which is nearly 2 degrees higher than in 2000 and about 6 degrees higher than long term average. Power demand in January was slightly less than 7.9 TWh, being about 0.5% less than in 2000. The power consumption in Finland during the past 12 months exceeded 79.3 TWh, which is less than 2% higher than during the previous 12 months. In February 2001 the average temperature was - 10 deg C, which was about 5 degrees lower than in February 2000. Because of this the power consumption in February 2001 increased by 5%. Power consumption in February was 7.5 TWh. The maximum hourly output of power plants in Finland was 13310 MW. Power consumption of Finnish households in February 2001 was about 10% higher than in February 2000, and in industry the increase was nearly zero. The utilization rate in forest industry in February 2001 decreased from the value of February 2000 by 5%, being only about 89%. The power consumption of the past 12 months (Feb. 2000 - Feb. 2001) was 79.6 TWh. Generation of hydroelectric power in Finland during January - February 2001 was 10% higher than a year before. The generation of hydroelectric power in Jan. - Feb. 2001 was nearly 2.7 TWh, corresponding to 17% of the power demand in Finland. The output of hydroelectric power in Finland during the past 12 months was 14.7 TWh. The increase from the previous 12 months was 17% corresponding to over 18% of the power demand in Finland. Wind power generation in Jan. - Feb. 2001 was exceeded slightly 10 GWh, while in 2000 the corresponding output was 20 GWh. The degree of utilization of Finnish nuclear power plants in Jan. - Feb. 2001 was high. The output of these plants was 3.8 TWh, being about 1% less than in Jan. - Feb. 2000. The main cause for the

Statistical Power of Psychological Research: What Have We Gained in 20 Years?

Science.gov (United States)

Rossi, Joseph S.

1990-01-01

Calculated power for 6,155 statistical tests in 221 journal articles published in 1982 volumes of "Journal of Abnormal Psychology,""Journal of Consulting and Clinical Psychology," and "Journal of Personality and Social Psychology." Power to detect small, medium, and large effects was .17, .57, and .83, respectively. Concluded that power of…

Study of acute renal insufficiency and chronic renal insufficiency using radioisotopes

International Nuclear Information System (INIS)

Raynaud, C.

1976-01-01

Radioisotopic renal function tests are of assistance to diagnose and follow-up the course of renal insufficiency. The radioisotopic renogram is useful in assessing the response to therapy of child obstructive uropathies and evaluating renal transplant function. The renal scan is helpful, in an emergency service, to differenciate chronic renal insufficiency from acute renal insufficiency. Hg renal uptake test provides informations on physiopathological problems. Among them, the following problems are emphasized: evolution of a nonfunctioning kidney, control of the success of a reparative surgery and of bilateral obstructive uropathies with unilateral symptoms [fr

Development and testing of improved statistical wind power forecasting methods.

Energy Technology Data Exchange (ETDEWEB)

Mendes, J.; Bessa, R.J.; Keko, H.; Sumaili, J.; Miranda, V.; Ferreira, C.; Gama, J.; Botterud, A.; Zhou, Z.; Wang, J. (Decision and Information Sciences); (INESC Porto)

2011-12-06

Wind power forecasting (WPF) provides important inputs to power system operators and electricity market participants. It is therefore not surprising that WPF has attracted increasing interest within the electric power industry. In this report, we document our research on improving statistical WPF algorithms for point, uncertainty, and ramp forecasting. Below, we provide a brief introduction to the research presented in the following chapters. For a detailed overview of the state-of-the-art in wind power forecasting, we refer to [1]. Our related work on the application of WPF in operational decisions is documented in [2]. Point forecasts of wind power are highly dependent on the training criteria used in the statistical algorithms that are used to convert weather forecasts and observational data to a power forecast. In Chapter 2, we explore the application of information theoretic learning (ITL) as opposed to the classical minimum square error (MSE) criterion for point forecasting. In contrast to the MSE criterion, ITL criteria do not assume a Gaussian distribution of the forecasting errors. We investigate to what extent ITL criteria yield better results. In addition, we analyze time-adaptive training algorithms and how they enable WPF algorithms to cope with non-stationary data and, thus, to adapt to new situations without requiring additional offline training of the model. We test the new point forecasting algorithms on two wind farms located in the U.S. Midwest. Although there have been advancements in deterministic WPF, a single-valued forecast cannot provide information on the dispersion of observations around the predicted value. We argue that it is essential to generate, together with (or as an alternative to) point forecasts, a representation of the wind power uncertainty. Wind power uncertainty representation can take the form of probabilistic forecasts (e.g., probability density function, quantiles), risk indices (e.g., prediction risk index) or scenarios

Effect size, confidence intervals and statistical power in psychological research.

Directory of Open Access Journals (Sweden)

Téllez A.

2015-07-01

Full Text Available Quantitative psychological research is focused on detecting the occurrence of certain population phenomena by analyzing data from a sample, and statistics is a particularly helpful mathematical tool that is used by researchers to evaluate hypotheses and make decisions to accept or reject such hypotheses. In this paper, the various statistical tools in psychological research are reviewed. The limitations of null hypothesis significance testing (NHST and the advantages of using effect size and its respective confidence intervals are explained, as the latter two measurements can provide important information about the results of a study. These measurements also can facilitate data interpretation and easily detect trivial effects, enabling researchers to make decisions in a more clinically relevant fashion. Moreover, it is recommended to establish an appropriate sample size by calculating the optimum statistical power at the moment that the research is designed. Psychological journal editors are encouraged to follow APA recommendations strictly and ask authors of original research studies to report the effect size, its confidence intervals, statistical power and, when required, any measure of clinical significance. Additionally, we must account for the teaching of statistics at the graduate level. At that level, students do not receive sufficient information concerning the importance of using different types of effect sizes and their confidence intervals according to the different types of research designs; instead, most of the information is focused on the various tools of NHST.

SIESE - trimestrial bulletin - Synthesis 1995. Electric power summary statistics for Brazil

International Nuclear Information System (INIS)

1995-01-01

This bulletin presents the electric power summary statistics, which cover the performance of the power system for the whole of the utilities in 1995. It offers tables with revised data concerning the last two years based on updated information supplied by both the electric utilities and the SIESE's responsibility centers. 6 figs., 36 tabs

[Addison's disease : Primary adrenal insufficiency].

Science.gov (United States)

Pulzer, A; Burger-Stritt, S; Hahner, S

2016-05-01

Adrenal insufficiency, a rare disorder which is characterized by the inadequate production or absence of adrenal hormones, may be classified as primary adrenal insufficiency in case of direct affection of the adrenal glands or secondary adrenal insufficiency, which is mostly due to pituitary or hypothalamic disease. Primary adrenal insufficiency affects 11 of 100,000 individuals. Clinical symptoms are mainly nonspecific and include fatigue, weight loss, and hypotension. The diagnostic test of choice is dynamic testing with synthetic ACTH. Patients suffering from chronic adrenal insufficiency require lifelong hormone supplementation. Education in dose adaption during physical and mental stress or emergency situations is essential to prevent life-threatening adrenal crises. Patients with adrenal insufficiency should carry an emergency card and emergency kit with them.

Statistical power to detect violation of the proportional hazards assumption when using the Cox regression model.

Science.gov (United States)

Austin, Peter C

2018-01-01

The use of the Cox proportional hazards regression model is widespread. A key assumption of the model is that of proportional hazards. Analysts frequently test the validity of this assumption using statistical significance testing. However, the statistical power of such assessments is frequently unknown. We used Monte Carlo simulations to estimate the statistical power of two different methods for detecting violations of this assumption. When the covariate was binary, we found that a model-based method had greater power than a method based on cumulative sums of martingale residuals. Furthermore, the parametric nature of the distribution of event times had an impact on power when the covariate was binary. Statistical power to detect a strong violation of the proportional hazards assumption was low to moderate even when the number of observed events was high. In many data sets, power to detect a violation of this assumption is likely to be low to modest.

Empirical Statistical Power for Testing Multilocus Genotypic Effects under Unbalanced Designs Using a Gibbs Sampler

Directory of Open Access Journals (Sweden)

Chaeyoung Lee

2012-11-01

Full Text Available Epistasis that may explain a large portion of the phenotypic variation for complex economic traits of animals has been ignored in many genetic association studies. A Baysian method was introduced to draw inferences about multilocus genotypic effects based on their marginal posterior distributions by a Gibbs sampler. A simulation study was conducted to provide statistical powers under various unbalanced designs by using this method. Data were simulated by combined designs of number of loci, within genotype variance, and sample size in unbalanced designs with or without null combined genotype cells. Mean empirical statistical power was estimated for testing posterior mean estimate of combined genotype effect. A practical example for obtaining empirical statistical power estimates with a given sample size was provided under unbalanced designs. The empirical statistical powers would be useful for determining an optimal design when interactive associations of multiple loci with complex phenotypes were examined.

Wind Power Statistics Sweden 2009; Vindkraftstatistik 2009

Energy Technology Data Exchange (ETDEWEB)

2010-04-15

In 2009, wind power produced 2.5 TWh, an increase of 26 percent over the previous year. Throughout the period 2003-2009 has production of electricity from wind power almost quadrupled. Sweden's total net production of electricity amounted, according to provisional statistics for 2009, to 133.7 TWh. The year 2007 wind energy's share passed 1.0 percent of total net production of electricity for the first time. In 2008 the proportion was 1.4 percent, and in 2009 to almost 1.9 percent of total net production. Total installed power 2009 was 1448 MW and the number of plants was 1359, an inckW{sub pse} with 363 MW and 198 resp. from 2008. In 2009, there were three main support system for wind power in Sweden: the certificate system; the wind pilot project; and the environmental bonus. The electricity certificate system is a market-based support system for electricity generation from renewables which includes wind power as one of the approved techniques. The system was introduced in 2003 and aims to increase the production of electricity from renewable energy sources by 25 TWh from 2002 levels by 2020.. Wind pilot support is a support to the market for large-scale wind power. Support aims to reduce the cost of the creation of new wind energy and promoting new technologies. Wind Pilot Aid, which has existed since 2003, has been extended until in 2012 and has increased by 350 million SEK (about 36 M Euro) for the period 2008-2012. The environmental bonus, which means a tax subsidy, has been stepped down for each year until and by the year 2009, which was the last year. In 2009, environmental bonus was 0.12 SEK/kWh for electricity from offshore wind. For onshore wind power the environmentally bonus ceased in 2008

Ten-year statistics of the electric power supply. Status and tendencies

International Nuclear Information System (INIS)

2001-12-01

The ten-year statistics of the electric power supply in Denmark for 1991-2000 presents in tables and figures the trend of the electric power supply sector during the last ten years. The tables and figures present information on total energy consumption, combined heat and power generation, fuel consumption and the environment, the technical systems, economy and pricing, organization of the electricity supply, and information on electricity prices and taxes for households and industry in various countries. (LN)

Statistical testing and power analysis for brain-wide association study.

Science.gov (United States)

Gong, Weikang; Wan, Lin; Lu, Wenlian; Ma, Liang; Cheng, Fan; Cheng, Wei; Grünewald, Stefan; Feng, Jianfeng

2018-04-05

The identification of connexel-wise associations, which involves examining functional connectivities between pairwise voxels across the whole brain, is both statistically and computationally challenging. Although such a connexel-wise methodology has recently been adopted by brain-wide association studies (BWAS) to identify connectivity changes in several mental disorders, such as schizophrenia, autism and depression, the multiple correction and power analysis methods designed specifically for connexel-wise analysis are still lacking. Therefore, we herein report the development of a rigorous statistical framework for connexel-wise significance testing based on the Gaussian random field theory. It includes controlling the family-wise error rate (FWER) of multiple hypothesis testings using topological inference methods, and calculating power and sample size for a connexel-wise study. Our theoretical framework can control the false-positive rate accurately, as validated empirically using two resting-state fMRI datasets. Compared with Bonferroni correction and false discovery rate (FDR), it can reduce false-positive rate and increase statistical power by appropriately utilizing the spatial information of fMRI data. Importantly, our method bypasses the need of non-parametric permutation to correct for multiple comparison, thus, it can efficiently tackle large datasets with high resolution fMRI images. The utility of our method is shown in a case-control study. Our approach can identify altered functional connectivities in a major depression disorder dataset, whereas existing methods fail. A software package is available at https://github.com/weikanggong/BWAS. Copyright © 2018 Elsevier B.V. All rights reserved.

Power, effects, confidence, and significance: an investigation of statistical practices in nursing research.

Science.gov (United States)

Gaskin, Cadeyrn J; Happell, Brenda

2014-05-01

To (a) assess the statistical power of nursing research to detect small, medium, and large effect sizes; (b) estimate the experiment-wise Type I error rate in these studies; and (c) assess the extent to which (i) a priori power analyses, (ii) effect sizes (and interpretations thereof), and (iii) confidence intervals were reported. Statistical review. Papers published in the 2011 volumes of the 10 highest ranked nursing journals, based on their 5-year impact factors. Papers were assessed for statistical power, control of experiment-wise Type I error, reporting of a priori power analyses, reporting and interpretation of effect sizes, and reporting of confidence intervals. The analyses were based on 333 papers, from which 10,337 inferential statistics were identified. The median power to detect small, medium, and large effect sizes was .40 (interquartile range [IQR]=.24-.71), .98 (IQR=.85-1.00), and 1.00 (IQR=1.00-1.00), respectively. The median experiment-wise Type I error rate was .54 (IQR=.26-.80). A priori power analyses were reported in 28% of papers. Effect sizes were routinely reported for Spearman's rank correlations (100% of papers in which this test was used), Poisson regressions (100%), odds ratios (100%), Kendall's tau correlations (100%), Pearson's correlations (99%), logistic regressions (98%), structural equation modelling/confirmatory factor analyses/path analyses (97%), and linear regressions (83%), but were reported less often for two-proportion z tests (50%), analyses of variance/analyses of covariance/multivariate analyses of variance (18%), t tests (8%), Wilcoxon's tests (8%), Chi-squared tests (8%), and Fisher's exact tests (7%), and not reported for sign tests, Friedman's tests, McNemar's tests, multi-level models, and Kruskal-Wallis tests. Effect sizes were infrequently interpreted. Confidence intervals were reported in 28% of papers. The use, reporting, and interpretation of inferential statistics in nursing research need substantial

A generalized model to estimate the statistical power in mitochondrial disease studies involving 2×k tables.

Directory of Open Access Journals (Sweden)

Jacobo Pardo-Seco

Full Text Available BACKGROUND: Mitochondrial DNA (mtDNA variation (i.e. haplogroups has been analyzed in regards to a number of multifactorial diseases. The statistical power of a case-control study determines the a priori probability to reject the null hypothesis of homogeneity between cases and controls. METHODS/PRINCIPAL FINDINGS: We critically review previous approaches to the estimation of the statistical power based on the restricted scenario where the number of cases equals the number of controls, and propose a methodology that broadens procedures to more general situations. We developed statistical procedures that consider different disease scenarios, variable sample sizes in cases and controls, and variable number of haplogroups and effect sizes. The results indicate that the statistical power of a particular study can improve substantially by increasing the number of controls with respect to cases. In the opposite direction, the power decreases substantially when testing a growing number of haplogroups. We developed mitPower (http://bioinformatics.cesga.es/mitpower/, a web-based interface that implements the new statistical procedures and allows for the computation of the a priori statistical power in variable scenarios of case-control study designs, or e.g. the number of controls needed to reach fixed effect sizes. CONCLUSIONS/SIGNIFICANCE: The present study provides with statistical procedures for the computation of statistical power in common as well as complex case-control study designs involving 2×k tables, with special application (but not exclusive to mtDNA studies. In order to reach a wide range of researchers, we also provide a friendly web-based tool--mitPower--that can be used in both retrospective and prospective case-control disease studies.

Ten-year statistics of the electric power supply. Status and tendencies

International Nuclear Information System (INIS)

2000-12-01

The ten-year statistics of the electric power supply in Denmark for 1990-1999 presents in tables and figures the trend of the electric power supply sector during the last ten years. The tables and figures present information on total energy consumption, combined heat and power generation, fuel consumption and the environment, the technical systems, economy and pricing, organization of the electricity supply, auto-production of electricity and information on electricity prices and taxes for households and industry in various countries. (LN)

Reliability of equipments and theory of frequency statistics and Bayesian decision

International Nuclear Information System (INIS)

Procaccia, H.; Clarotti, C.A.

1992-01-01

The rapid development of Bayesian techniques use in the domain of industrial risk is a recent phenomenon linked to the development of powerful computers. These techniques involve a reasoning well adapted to experimental logics, based on the dynamical knowledge enrichment with experience data. In the framework of reliability studies and statistical decision making, these methods differ slightly from the methods commonly used to evaluate the reliability of systems and from classical theoretical frequency statistics. This particular approach is described in this book and illustrated with many examples of application (power plants, pressure vessels, industrial installations etc..). These examples generally concern the risk management in the cases where the application of rules and the respect of norms become insufficient. It is now well known that the risk cannot be reduced to zero and that its evaluation must be performed using statistics, taking into account the possible accident processes and also the investments necessary to avoid them (service life, failure, maintenance costs and availability of materials). The result is the optimizing of a decision process about rare or uncertain events. (J.S.)

Model output statistics applied to wind power prediction

Energy Technology Data Exchange (ETDEWEB)

Joensen, A; Giebel, G; Landberg, L [Risoe National Lab., Roskilde (Denmark); Madsen, H; Nielsen, H A [The Technical Univ. of Denmark, Dept. of Mathematical Modelling, Lyngby (Denmark)

1999-03-01

Being able to predict the output of a wind farm online for a day or two in advance has significant advantages for utilities, such as better possibility to schedule fossil fuelled power plants and a better position on electricity spot markets. In this paper prediction methods based on Numerical Weather Prediction (NWP) models are considered. The spatial resolution used in NWP models implies that these predictions are not valid locally at a specific wind farm. Furthermore, due to the non-stationary nature and complexity of the processes in the atmosphere, and occasional changes of NWP models, the deviation between the predicted and the measured wind will be time dependent. If observational data is available, and if the deviation between the predictions and the observations exhibits systematic behavior, this should be corrected for; if statistical methods are used, this approaches is usually referred to as MOS (Model Output Statistics). The influence of atmospheric turbulence intensity, topography, prediction horizon length and auto-correlation of wind speed and power is considered, and to take the time-variations into account, adaptive estimation methods are applied. Three estimation techniques are considered and compared, Extended Kalman Filtering, recursive least squares and a new modified recursive least squares algorithm. (au) EU-JOULE-3. 11 refs.

Statistical analysis of human maintenance failures of a nuclear power plant

International Nuclear Information System (INIS)

Pyy, P.

2000-01-01

In this paper, a statistical study of faults caused by maintenance activities is presented. The objective of the study was to draw conclusions on the unplanned effects of maintenance on nuclear power plant safety and system availability. More than 4400 maintenance history reports from the years 1992-1994 of Olkiluoto BWR nuclear power plant (NPP) were analysed together with the maintenance personnel. The human action induced faults were classified, e.g., according to their multiplicity and effects. This paper presents and discusses the results of a statistical analysis of the data. Instrumentation and electrical components are especially prone to human failures. Many human failures were found in safety related systems. Similarly, several failures remained latent from outages to power operation. The safety significance was generally small. Modifications are an important source of multiple human failures. Plant maintenance data is a good source of human reliability data and it should be used more, in future. (orig.)

Statistical power to detect change in a mangrove shoreline fish community adjacent to a nuclear power plant.

Science.gov (United States)

Dolan, T E; Lynch, P D; Karazsia, J L; Serafy, J E

2016-03-01

An expansion is underway of a nuclear power plant on the shoreline of Biscayne Bay, Florida, USA. While the precise effects of its construction and operation are unknown, impacts on surrounding marine habitats and biota are considered by experts to be likely. The objective of the present study was to determine the adequacy of an ongoing monitoring survey of fish communities associated with mangrove habitats directly adjacent to the power plant to detect fish community changes, should they occur, at three spatial scales. Using seasonally resolved data recorded during 532 fish surveys over an 8-year period, power analyses were performed for four mangrove fish metrics (fish diversity, fish density, and the occurrence of two ecologically important fish species: gray snapper (Lutjanus griseus) and goldspotted killifish (Floridichthys carpio). Results indicated that the monitoring program at current sampling intensity allows for detection of <33% changes in fish density and diversity metrics in both the wet and the dry season in the two larger study areas. Sampling effort was found to be insufficient in either season to detect changes at this level (<33%) in species-specific occurrence metrics for the two fish species examined. The option of supplementing ongoing, biological monitoring programs for improved, focused change detection deserves consideration from both ecological and cost-benefit perspectives.

Effect size and statistical power in the rodent fear conditioning literature - A systematic review.

Science.gov (United States)

Carneiro, Clarissa F D; Moulin, Thiago C; Macleod, Malcolm R; Amaral, Olavo B

2018-01-01

Proposals to increase research reproducibility frequently call for focusing on effect sizes instead of p values, as well as for increasing the statistical power of experiments. However, it is unclear to what extent these two concepts are indeed taken into account in basic biomedical science. To study this in a real-case scenario, we performed a systematic review of effect sizes and statistical power in studies on learning of rodent fear conditioning, a widely used behavioral task to evaluate memory. Our search criteria yielded 410 experiments comparing control and treated groups in 122 articles. Interventions had a mean effect size of 29.5%, and amnesia caused by memory-impairing interventions was nearly always partial. Mean statistical power to detect the average effect size observed in well-powered experiments with significant differences (37.2%) was 65%, and was lower among studies with non-significant results. Only one article reported a sample size calculation, and our estimated sample size to achieve 80% power considering typical effect sizes and variances (15 animals per group) was reached in only 12.2% of experiments. Actual effect sizes correlated with effect size inferences made by readers on the basis of textual descriptions of results only when findings were non-significant, and neither effect size nor power correlated with study quality indicators, number of citations or impact factor of the publishing journal. In summary, effect sizes and statistical power have a wide distribution in the rodent fear conditioning literature, but do not seem to have a large influence on how results are described or cited. Failure to take these concepts into consideration might limit attempts to improve reproducibility in this field of science.

Statistics Clinic

Science.gov (United States)

Feiveson, Alan H.; Foy, Millennia; Ploutz-Snyder, Robert; Fiedler, James

2014-01-01

Do you have elevated p-values? Is the data analysis process getting you down? Do you experience anxiety when you need to respond to criticism of statistical methods in your manuscript? You may be suffering from Insufficient Statistical Support Syndrome (ISSS). For symptomatic relief of ISSS, come for a free consultation with JSC biostatisticians at our help desk during the poster sessions at the HRP Investigators Workshop. Get answers to common questions about sample size, missing data, multiple testing, when to trust the results of your analyses and more. Side effects may include sudden loss of statistics anxiety, improved interpretation of your data, and increased confidence in your results.

[Effect sizes, statistical power and sample sizes in "the Japanese Journal of Psychology"].

Science.gov (United States)

Suzukawa, Yumi; Toyoda, Hideki

2012-04-01

This study analyzed the statistical power of research studies published in the "Japanese Journal of Psychology" in 2008 and 2009. Sample effect sizes and sample statistical powers were calculated for each statistical test and analyzed with respect to the analytical methods and the fields of the studies. The results show that in the fields like perception, cognition or learning, the effect sizes were relatively large, although the sample sizes were small. At the same time, because of the small sample sizes, some meaningful effects could not be detected. In the other fields, because of the large sample sizes, meaningless effects could be detected. This implies that researchers who could not get large enough effect sizes would use larger samples to obtain significant results.

Power spectra as a diagnostic tool in probing statistical/nonstatistical behavior in unimolecular reactions

Science.gov (United States)

Chang, Xiaoyen Y.; Sewell, Thomas D.; Raff, Lionel M.; Thompson, Donald L.

1992-11-01

The possibility of utilizing different types of power spectra obtained from classical trajectories as a diagnostic tool to identify the presence of nonstatistical dynamics is explored by using the unimolecular bond-fission reactions of 1,2-difluoroethane and the 2-chloroethyl radical as test cases. In previous studies, the reaction rates for these systems were calculated by using a variational transition-state theory and classical trajectory methods. A comparison of the results showed that 1,2-difluoroethane is a nonstatistical system, while the 2-chloroethyl radical behaves statistically. Power spectra for these two systems have been generated under various conditions. The characteristics of these spectra are as follows: (1) The spectra for the 2-chloroethyl radical are always broader and more coupled to other modes than is the case for 1,2-difluoroethane. This is true even at very low levels of excitation. (2) When an internal energy near or above the dissociation threshold is initially partitioned into a local C-H stretching mode, the power spectra for 1,2-difluoroethane broaden somewhat, but discrete and somewhat isolated bands are still clearly evident. In contrast, the analogous power spectra for the 2-chloroethyl radical exhibit a near complete absence of isolated bands. The general appearance of the spectrum suggests a very high level of mode-to-mode coupling, large intramolecular vibrational energy redistribution (IVR) rates, and global statistical behavior. (3) The appearance of the power spectrum for the 2-chloroethyl radical is unaltered regardless of whether the initial C-H excitation is in the CH2 or the CH2Cl group. This result also suggests statistical behavior. These results are interpreted to mean that power spectra may be used as a diagnostic tool to assess the statistical character of a system. The presence of a diffuse spectrum exhibiting a nearly complete loss of isolated structures indicates that the dissociation dynamics of the molecule will

Statistical algorithm for automated signature analysis of power spectral density data

International Nuclear Information System (INIS)

Piety, K.R.

1977-01-01

A statistical algorithm has been developed and implemented on a minicomputer system for on-line, surveillance applications. Power spectral density (PSD) measurements on process signals are the performance signatures that characterize the ''health'' of the monitored equipment. Statistical methods provide a quantitative basis for automating the detection of anomalous conditions. The surveillance algorithm has been tested on signals from neutron sensors, proximeter probes, and accelerometers to determine its potential for monitoring nuclear reactors and rotating machinery

Relationship between clinical signs and symptoms of convergence insufficiency.

Science.gov (United States)

Bade, Annette; Boas, Mark; Gallaway, Michael; Mitchell, G Lynn; Scheiman, Mitchell; Kulp, Marjean T; Cotter, Susan A; Rouse, Michael

2013-09-01

The percentage of children who are symptomatic has been shown to increase with the number of signs of convergence insufficiency (CI). Our goal was to investigate whether there is a relationship between the severity of the clinical signs of CI and symptom level reported in children with a three-sign symptomatic CI. The Convergence Insufficiency Treatment Trial enrolled 221 children with symptomatic CI from ages 9 to 17 years. Inclusion criteria included the following three signs of CI: (1) exophoria at near at least 4Δ greater than at distance, (2) insufficient positive fusional vergence (PFV) at near, and (3) a receded near point of convergence (NPC) of 6 cm break or greater. The relationships between the severity of each sign of CI (mild, moderate, and severe) and the level of symptoms as measured by the Convergence Insufficiency Symptom Survey (CISS) at baseline were evaluated. Mean CISS scores were not significantly different between mild, moderate, and severe exophoria (p = 0.60), PFV blur (p = 0.99), Sheard's criterion (p = 0.89), or NPC break (p = 0.84). There was also no difference between the frequency of subjects scoring at mild, moderate, or severe levels on the CISS and the severity of each sign of CI. Correlations between individual clinical signs and the CISS score were very low and not statistically significant. Among symptomatic children with a CISS score of 16 or higher and three clinical signs of CI, there is no further association between the severity of the clinical signs and their level of symptoms.

A Note on Comparing the Power of Test Statistics at Low Significance Levels.

Science.gov (United States)

Morris, Nathan; Elston, Robert

2011-01-01

It is an obvious fact that the power of a test statistic is dependent upon the significance (alpha) level at which the test is performed. It is perhaps a less obvious fact that the relative performance of two statistics in terms of power is also a function of the alpha level. Through numerous personal discussions, we have noted that even some competent statisticians have the mistaken intuition that relative power comparisons at traditional levels such as α = 0.05 will be roughly similar to relative power comparisons at very low levels, such as the level α = 5 × 10 -8 , which is commonly used in genome-wide association studies. In this brief note, we demonstrate that this notion is in fact quite wrong, especially with respect to comparing tests with differing degrees of freedom. In fact, at very low alpha levels the cost of additional degrees of freedom is often comparatively low. Thus we recommend that statisticians exercise caution when interpreting the results of power comparison studies which use alpha levels that will not be used in practice.

Adalimumab treatment in patients with rheumatoid arthritis with renal insufficiency.

Science.gov (United States)

Sumida, Keiichi; Ubara, Yoshifumi; Suwabe, Tatsuya; Hayami, Noriko; Hiramatsu, Rikako; Hasegawa, Eiko; Yamanouchi, Masayuki; Hoshino, Junichi; Sawa, Naoki; Takaichi, Kenmei

2013-03-01

To elucidate the safety of adalimumab for rheumatoid arthritis (RA) patients with renal insufficiency, including those with end-stage renal disease undergoing hemodialysis. Sixty-five RA patients, including 2 patients undergoing hemodialysis, treated with adalimumab in our hospital from December 1, 2008 to June 30, 2011 were retrospectively analyzed. Renal function was evaluated by the estimated glomerular filtration rate (eGFR) calculated from the Cockcroft-Gault formula at the start and end of followup after adalimumab treatment. The proportion of the patients who discontinued or switched adalimumab treatment and the change of the eGFR were compared between patients with (n = 39) and without (n = 26) renal insufficiency, defined as an eGFR patients who discontinued or switched adalimumab treatment (51.3% versus 50.0%; P = 0.53). The mean ± SD changes of eGFR were from 41.6 ± 13.3 to 43.4 ± 17.9 ml/minute/1.73 m(2) in patients with renal insufficiency and from 83.6 ± 17.5 to 83.0 ± 16.8 ml/minute/1.73 m(2) in patients without renal insufficiency, and the differences in each group were not statistically significant (P = 0.92 and P = 0.78, respectively). No severe infections or other severe adverse events were observed in either group during adalimumab treatment. Our data indicate that adalimumab does not worsen renal function and has no serious adverse events even for RA patients with renal insufficiency, including those undergoing hemodialysis, and suggest that it could be a potential therapeutic option for them. Copyright © 2013 by the American College of Rheumatology.

[Perinatal complications in patients with chronic renal insufficiency on hemodialysis].

Science.gov (United States)

Vázquez-Rodríguez, Juan Gustavo; del Angel-García, Guadalupe

2010-09-01

Pregnant patients with chronic renal insufficiency treated with hemodialysis experience adverse perinatal results. To compare perinatal complications of patients with chronic renal insufficiency undergoing hemodialysis who become pregnant vs. the complications of women with chronic renal insufficiency not undergoing dialysis but who then require dialysis during gestation. Transversal and retrospective study that included three patients with chronic renal insufficiency on chronic hemodialysis who became pregnant (group A) and three patients with chronic renal insufficiency without hemodialysis at the time of conception but who required dialysis during gestation (group B). Perinatal results were compared. Statistical analysis was performed with measures of central tendency and dispersion and Student t-test. Group A had 25 sessions vs. group B with 29 hemodialysis sessions (p = 0.88). Maternal complications were anemia 100% (six cases), Cesarean delivery 83.3% (group A 2 cases vs. group B 2 cases), preeclampsia 50% (group A 2 cases vs. group B 1 case), uncontrolled hypertension 50% (group A 2 cases vs. group B 1 case), preterm delivery 50% (group A 2 cases vs. group B 1 case), transfusion 33.3% (group A 2 cases), polyhydramnios 33.3% (group A 1 case vs. group B 1 case) and abortion 16.6% (group A 1 case). Fetal complications included fetal loss 16.6% (group A 1 case), neonatal mortality 33.3% (group A 1 cases vs. group B 1 case), prematurity 50% (group A2 cases vs. group B 1 case), fetal distress 50% (group A 1 case vs. group B 2 cases), respiratory failure 33.3% (group A 2 cases) and fetal growth restriction 16.6% (group A 1 case). Frequency of perinatal complications is elevated in both groups.

Reliability of dc power supplies in nuclear power plant application

International Nuclear Information System (INIS)

Eisenhut, D.G.

1978-01-01

In June 1977 the reliability of dc power supplies at nuclear power facilities was questioned. It was postulated that a sudden gross failure of the redundant dc power supplies might occur during normal plant operation, and that this could lead to insufficient shutdown cooling of the reactor core. It was further suggested that this potential for insufficient cooling is great enough to warrant consideration of prompt remedies. The work described herein was part of the NRC staff's efforts aimed towards putting the performance of dc power supplies in proper perspective and was mainly directed towards the particular concern raised at that time. While the staff did not attempt to perform a systematic study of overall dc power supply reliability including all possible failure modes for such supplies, the work summarized herein describes how a probabilistic approach was used to supplement our more usual deterministic approach to reactor safety. Our evaluation concluded that the likelihood of dc power supply failures leading to insufficient shutdown cooling of the reactor core is sufficiently small as to not require any immediate action

A statistical estimator for the boiler power and its related parameters

International Nuclear Information System (INIS)

Tang, H.

2001-01-01

To determine the boiler power accurately is important for both controlling the plant and maximizing the plant productivity. There are two computed boiler powers for each boiler. They are steam based boiler power and feedwater based boiler power. The steam based boiler power is computed as the enthalpy difference between the feedwater enthalpy and the boiler steam enthalpy. The feedwater based boiler power is computed as enthalpy absorbed by the feedwater. The steam based boiler power is computed in RRS program and used in calibrating the measured reactor power, while the feedwater based boiler power is computed in CSTAT program and used for indication. Since the steam based boiler power is used as feedback in the reactor control, it is chosen to be the one estimated in this work. Because the boiler power employs steam flow, feedwater flow and feedwater temperature measurements, and because any measurement contains constant or drifting noise and bias, the reconciliation and rectification procedures are needed to determine the boiler power more accurately. A statistic estimator is developed to perform the function of data reconciliation, gross error detection and instruments performance monitoring

A critical discussion of null hypothesis significance testing and statistical power analysis within psychological research

DEFF Research Database (Denmark)

Jones, Allan; Sommerlund, Bo

2007-01-01

The uses of null hypothesis significance testing (NHST) and statistical power analysis within psychological research are critically discussed. The article looks at the problems of relying solely on NHST when dealing with small and large sample sizes. The use of power-analysis in estimating...... the potential error introduced by small and large samples is advocated. Power analysis is not recommended as a replacement to NHST but as an additional source of information about the phenomena under investigation. Moreover, the importance of conceptual analysis in relation to statistical analysis of hypothesis...

The Effects of Flare Definitions on the Statistics of Derived Flare Distrubtions

Science.gov (United States)

Ryan, Daniel; Dominique, Marie; Seaton, Daniel B.; Stegen, Koen; White, Arthur

2016-05-01

The statistical examination of solar flares is crucial to revealing their global characteristics and behaviour. However, statistical flare studies are often performed using standard but basic flare detection algorithms relying on arbitrary thresholds which may affect the derived flare distributions. We explore the effect of the arbitrary thresholds used in the GOES event list and LYRA Flare Finder algorithms. We find that there is a small but significant relationship between the power law exponent of the GOES flare peak flux frequency distribution and the algorithms’ flare start thresholds. We also find that the power law exponents of these distributions are not stable but appear to steepen with increasing peak flux. This implies that the observed flare size distribution may not be a power law at all. We show that depending on the true value of the exponent of the flare size distribution, this deviation from a power law may be due to flares missed by the flare detection algorithms. However, it is not possible determine the true exponent from GOES/XRS observations. Additionally we find that the PROBA2/LYRA flare size distributions are clearly non-power law. We show that this is consistent with an insufficient degradation correction which causes LYRA absolute irradiance values to be unreliable. This means that they should not be used for flare statistics or energetics unless degradation is adequately accounted for. However they can be used to study time variations over shorter timescales and for space weather monitoring.

Effect size and statistical power in the rodent fear conditioning literature – A systematic review

Science.gov (United States)

Macleod, Malcolm R.

2018-01-01

Proposals to increase research reproducibility frequently call for focusing on effect sizes instead of p values, as well as for increasing the statistical power of experiments. However, it is unclear to what extent these two concepts are indeed taken into account in basic biomedical science. To study this in a real-case scenario, we performed a systematic review of effect sizes and statistical power in studies on learning of rodent fear conditioning, a widely used behavioral task to evaluate memory. Our search criteria yielded 410 experiments comparing control and treated groups in 122 articles. Interventions had a mean effect size of 29.5%, and amnesia caused by memory-impairing interventions was nearly always partial. Mean statistical power to detect the average effect size observed in well-powered experiments with significant differences (37.2%) was 65%, and was lower among studies with non-significant results. Only one article reported a sample size calculation, and our estimated sample size to achieve 80% power considering typical effect sizes and variances (15 animals per group) was reached in only 12.2% of experiments. Actual effect sizes correlated with effect size inferences made by readers on the basis of textual descriptions of results only when findings were non-significant, and neither effect size nor power correlated with study quality indicators, number of citations or impact factor of the publishing journal. In summary, effect sizes and statistical power have a wide distribution in the rodent fear conditioning literature, but do not seem to have a large influence on how results are described or cited. Failure to take these concepts into consideration might limit attempts to improve reproducibility in this field of science. PMID:29698451

Statistical power of intervention analyses: simulation and empirical application to treated lumber prices

Science.gov (United States)

Jeffrey P. Prestemon

2009-01-01

Timber product markets are subject to large shocks deriving from natural disturbances and policy shifts. Statistical modeling of shocks is often done to assess their economic importance. In this article, I simulate the statistical power of univariate and bivariate methods of shock detection using time series intervention models. Simulations show that bivariate methods...

Determinants of Judgments of Explanatory Power: Credibility, Generality, and Statistical Relevance

Science.gov (United States)

Colombo, Matteo; Bucher, Leandra; Sprenger, Jan

2017-01-01

Explanation is a central concept in human psychology. Drawing upon philosophical theories of explanation, psychologists have recently begun to examine the relationship between explanation, probability and causality. Our study advances this growing literature at the intersection of psychology and philosophy of science by systematically investigating how judgments of explanatory power are affected by (i) the prior credibility of an explanatory hypothesis, (ii) the causal framing of the hypothesis, (iii) the perceived generalizability of the explanation, and (iv) the relation of statistical relevance between hypothesis and evidence. Collectively, the results of our five experiments support the hypothesis that the prior credibility of a causal explanation plays a central role in explanatory reasoning: first, because of the presence of strong main effects on judgments of explanatory power, and second, because of the gate-keeping role it has for other factors. Highly credible explanations are not susceptible to causal framing effects, but they are sensitive to the effects of normatively relevant factors: the generalizability of an explanation, and its statistical relevance for the evidence. These results advance current literature in the philosophy and psychology of explanation in three ways. First, they yield a more nuanced understanding of the determinants of judgments of explanatory power, and the interaction between these factors. Second, they show the close relationship between prior beliefs and explanatory power. Third, they elucidate the nature of abductive reasoning. PMID:28928679

Statistical tests for power-law cross-correlated processes

Science.gov (United States)

Podobnik, Boris; Jiang, Zhi-Qiang; Zhou, Wei-Xing; Stanley, H. Eugene

2011-12-01

For stationary time series, the cross-covariance and the cross-correlation as functions of time lag n serve to quantify the similarity of two time series. The latter measure is also used to assess whether the cross-correlations are statistically significant. For nonstationary time series, the analogous measures are detrended cross-correlations analysis (DCCA) and the recently proposed detrended cross-correlation coefficient, ρDCCA(T,n), where T is the total length of the time series and n the window size. For ρDCCA(T,n), we numerically calculated the Cauchy inequality -1≤ρDCCA(T,n)≤1. Here we derive -1≤ρDCCA(T,n)≤1 for a standard variance-covariance approach and for a detrending approach. For overlapping windows, we find the range of ρDCCA within which the cross-correlations become statistically significant. For overlapping windows we numerically determine—and for nonoverlapping windows we derive—that the standard deviation of ρDCCA(T,n) tends with increasing T to 1/T. Using ρDCCA(T,n) we show that the Chinese financial market's tendency to follow the U.S. market is extremely weak. We also propose an additional statistical test that can be used to quantify the existence of cross-correlations between two power-law correlated time series.

A Statistical Method for Aggregated Wind Power Plants to Provide Secondary Frequency Control

DEFF Research Database (Denmark)

Hu, Junjie; Ziras, Charalampos; Bindner, Henrik W.

2017-01-01

curtailment for aggregated wind power plants providing secondary frequency control (SFC) to the power system. By using historical SFC signals and wind speed data, we calculate metrics for the reserve provision error as a function of the scheduled wind power. We show that wind curtailment can be significantly......The increasing penetration of wind power brings significant challenges to power system operators due to the wind’s inherent uncertainty and variability. Traditionally, power plants and more recently demand response have been used to balance the power system. However, the use of wind power...... as a balancing-power source has also been investigated, especially for wind power dominated power systems such as Denmark. The main drawback is that wind power must be curtailed by setting a lower operating point, in order to offer upward regulation. We propose a statistical approach to reduce wind power...

Statistical power analysis a simple and general model for traditional and modern hypothesis tests

CERN Document Server

Murphy, Kevin R; Wolach, Allen

2014-01-01

Noted for its accessible approach, this text applies the latest approaches of power analysis to both null hypothesis and minimum-effect testing using the same basic unified model. Through the use of a few simple procedures and examples, the authors show readers with little expertise in statistical analysis how to obtain the values needed to carry out the power analysis for their research. Illustrations of how these analyses work and how they can be used to choose the appropriate criterion for defining statistically significant outcomes are sprinkled throughout. The book presents a simple and g

Insufficiency fracture after radiation therapy

Energy Technology Data Exchange (ETDEWEB)

Oh, Dong Ryul; Huh, Seung Jae [Dept.of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2014-12-15

Insufficiency fracture occurs when normal or physiological stress applied to weakened bone with demineralization and decreased elastic resistance. Recently, many studies reported the development of IF after radiation therapy (RT) in gynecological cancer, prostate cancer, anal cancer and rectal cancer. The RT-induced insufficiency fracture is a common complication during the follow-up using modern imaging studies. The clinical suspicion and knowledge the characteristic imaging patterns of insufficiency fracture is essential to differentiate it from metastatic bone lesions, because it sometimes cause severe pain, and it may be confused with bone metastasis.

Optimal glucocorticoid replacement in adrenal insufficiency.

Science.gov (United States)

Øksnes, Marianne; Ross, Richard; Løvås, Kristian

2015-01-01

Adrenal insufficiency (glucocorticoid deficiency) comprises a group of rare diseases, including primary adrenal insufficiency, secondary adrenal insufficiency and congenital adrenal hyperplasia. Lifesaving glucocorticoid therapy was introduced over 60 years ago, but since then a number of advances in treatment have taken place. Specifically, little is known about short- and long-term treatment effects, and morbidity and mortality. Over the past decade, systematic cohort and registry studies have described reduced health-related quality of life, an unfavourable metabolic profile and increased mortality in patients with adrenal insufficiency, which may relate to unphysiological glucocorticoid replacement. This has led to the development of new modes of replacement that aim to mimic normal glucocorticoid physiology. Here, evidence for the inadequacy of conventional glucocorticoid therapy and recent developments in treatment are reviewed, with an emphasis on primary adrenal insufficiency. Copyright © 2014 Elsevier Ltd. All rights reserved.

Air-chemistry "turbulence": power-law scaling and statistical regularity

Directory of Open Access Journals (Sweden)

H.-m. Hsu

2011-08-01

Full Text Available With the intent to gain further knowledge on the spectral structures and statistical regularities of surface atmospheric chemistry, the chemical gases (NO, NO₂, NO_x, CO, SO₂, and O₃ and aerosol (PM₁₀ measured at 74 air quality monitoring stations over the island of Taiwan are analyzed for the year of 2004 at hourly resolution. They represent a range of surface air quality with a mixed combination of geographic settings, and include urban/rural, coastal/inland, plain/hill, and industrial/agricultural locations. In addition to the well-known semi-diurnal and diurnal oscillations, weekly, and intermediate (20 ~ 30 days peaks are also identified with the continuous wavelet transform (CWT. The spectra indicate power-law scaling regions for the frequencies higher than the diurnal and those lower than the diurnal with the average exponents of −5/3 and −1, respectively. These dual-exponents are corroborated with those with the detrended fluctuation analysis in the corresponding time-lag regions. These exponents are mostly independent of the averages and standard deviations of time series measured at various geographic settings, i.e., the spatial inhomogeneities. In other words, they possess dominant universal structures. After spectral coefficients from the CWT decomposition are grouped according to the spectral bands, and inverted separately, the PDFs of the reconstructed time series for the high-frequency band demonstrate the interesting statistical regularity, −3 power-law scaling for the heavy tails, consistently. Such spectral peaks, dual-exponent structures, and power-law scaling in heavy tails are important structural information, but their relations to turbulence and mesoscale variability require further investigations. This could lead to a better understanding of the processes controlling air quality.

Statistical measurement of power spectrum density of large aperture optical component

International Nuclear Information System (INIS)

Xu Jiancheng; Xu Qiao; Chai Liqun

2010-01-01

According to the requirement of ICF, a method based on statistical theory has been proposed to measure the power spectrum density (PSD) of large aperture optical components. The method breaks the large-aperture wavefront into small regions, and obtains the PSD of the large-aperture wavefront by weighted averaging of the PSDs of the regions, where the weight factor is each region's area. Simulation and experiment demonstrate the effectiveness of the proposed method. They also show that, the obtained PSDs of the large-aperture wavefront by statistical method and sub-aperture stitching method fit well, when the number of small regions is no less than 8 x 8. The statistical method is not sensitive to translation stage's errors and environment instabilities, thus it is appropriate for PSD measurement during the process of optical fabrication. (authors)

The physical mechanism of successful treatment for cervical insufficiency

Science.gov (United States)

Baumer, Alexa; Amechi, Alexis; Codrington, Paige; Leftwich, Megan C.

2017-11-01

Cervical insufficiency is a medical condition during pregnancy in which the uterine cervix softens and begins to dilate before reaching full term, usually between 18 and 22 weeks gestation. It is the most common cause of second trimester pregnancy loss. One clinical technique used to treat cervical insufficiency is the cervical cerclage, a procedure to close the cervix with a purse-string stitch. There are conflicting findings on the efficacy of a cerclage, with most studies relying on statistical evidence. The purpose of this investigation is to examine the mechanical limitations of a cervical cerclage by pressurizing a stitched, synthetic cervix until rupture. A synthetic model of the cervix is generated using ultrasound images collected by clinical collaborators and fabricated with silicon to imitate physiological properties. Medical residents from The George Washington University Hospital stitch the synthetic cervixes using clinical techniques. Pressure transducers record the maximum force on the stitch before rupture. The results of this study will provide insight into the most effective clinical interventions and the mechanism of their success.

Demographic statistics pertaining to nuclear power reactor sites

International Nuclear Information System (INIS)

1979-10-01

Population statistics are presented for 145 nuclear power plant sites. Summary tables and figures are included that were developed to aid in the evaluation of trends and general patterns associated with the various parameters of interest, such as the proximity of nuclear plant sites to centers of population. The primary reason for publishing this information at this time is to provide a factual basis for use in discussions on the subject of reactor siting policy. The report is a revised and updated version of a draft report published in December 1977. Errors in the population data base have been corrected and new data tabulations added

Comparison of maintenance worker's human error events occurred at United States and domestic nuclear power plants. The proposal of the classification method with insufficient knowledge and experience and the classification result of its application

International Nuclear Information System (INIS)

Takagawa, Kenichi

2008-01-01

Human errors by maintenance workers in U.S. nuclear power plants were compared with those in Japanese nuclear power plants for the same period in order to identify the characteristics of such errors. As for U.S. events, cases which occurred during 2006 were selected from the Nuclear Information Database of the Institute to Nuclear Safety System while Japanese cases that occurred during the same period, were extracted from the Nuclear Information Archives (NUCIA) owned by JANTI. The most common cause of human errors was insufficient knowledge or experience' accounting for about 40% for U.S. cases and 50% or more of cases in Japan. To break down 'insufficient knowledge', we classified the contents of knowledge into five categories; method', 'nature', 'reason', 'scope' and 'goal', and classified the level of knowledge into four categories: 'known', 'comprehended', 'applied' and analytic'. By using this classification, the patterns of combination of each item of the content and the level of knowledge were compared. In the U.S. cases, errors due to 'insufficient knowledge of nature and insufficient knowledge of method' were prevalent while three other items', 'reason', scope' and 'goal' which involve work conditions among the contents of knowledge rarely occurred. In Japan, errors arising from 'nature not being comprehended' were rather prevalent while other cases were distributed evenly for all categories including the work conditions. For addressing insufficient knowledge or experience', we consider that the following approaches are valid: according to the knowledge level which is required for the work, the reflection of knowledge on the procedure or education materials, training and confirmation of understanding level, virtual practice and instruction of experience should be implemented. As for the knowledge on the work conditions, it is necessary to enter the work conditions in the procedure and education materials while conducting training or education. (author)

Nuclear power statistics 1985

International Nuclear Information System (INIS)

Oelgaard, P.L.

1986-06-01

In this report an attempt is made to collect literature data on nuclear power production and to present it on graphical form. Data is given not only for 1985, but for a number of years so that the trends in the development of nuclear power can be seen. The global capacity of nuclear power plants in operation and those in operation, under construction, or on order is considered. Further the average capacity factor for nuclear plants of a specific type and for various geographical areas is given. The contribution of nuclear power to the total electricity production is considered for a number of countries and areas. Finally, the accumulated years of commercial operation for the various reactor types up to the end of 1985 is presented. (author)

Simulations and cosmological inference: A statistical model for power spectra means and covariances

International Nuclear Information System (INIS)

Schneider, Michael D.; Knox, Lloyd; Habib, Salman; Heitmann, Katrin; Higdon, David; Nakhleh, Charles

2008-01-01

We describe an approximate statistical model for the sample variance distribution of the nonlinear matter power spectrum that can be calibrated from limited numbers of simulations. Our model retains the common assumption of a multivariate normal distribution for the power spectrum band powers but takes full account of the (parameter-dependent) power spectrum covariance. The model is calibrated using an extension of the framework in Habib et al. (2007) to train Gaussian processes for the power spectrum mean and covariance given a set of simulation runs over a hypercube in parameter space. We demonstrate the performance of this machinery by estimating the parameters of a power-law model for the power spectrum. Within this framework, our calibrated sample variance distribution is robust to errors in the estimated covariance and shows rapid convergence of the posterior parameter constraints with the number of training simulations.

Implementation of a Model Output Statistics based on meteorological variable screening for short‐term wind power forecast

DEFF Research Database (Denmark)

Ranaboldo, Matteo; Giebel, Gregor; Codina, Bernat

2013-01-01

A combination of physical and statistical treatments to post‐process numerical weather predictions (NWP) outputs is needed for successful short‐term wind power forecasts. One of the most promising and effective approaches for statistical treatment is the Model Output Statistics (MOS) technique....... The proposed MOS performed well in both wind farms, and its forecasts compare positively with an actual operative model in use at Risø DTU and other MOS types, showing minimum BIAS and improving NWP power forecast of around 15% in terms of root mean square error. Further improvements could be obtained...

Nordel - Availability statistics for thermal power plants 1995. (Denmark, Finland, Sweden)

International Nuclear Information System (INIS)

1996-01-01

The power companies of Denmark, Finland and Sweden have agreed on almost identical procedures for the recording and analysing of data describing the availability of power producing units over a certain capacity. Since 1975 the data for all three countries have been summarized and published in a joint report. The purpose of this report is to present some basic information about the operation of power producing units in the three countries. Referring to the report, companies or bodies will be able to exchange more detailed information with other companies or bodies in any of the countries. The report includes power producing units using fossil fuels, nuclear power plants and gas turbines. The information is presented separately for each country with a joint NORDEL statistics for units using fossil fuels, arranged in separate groups according to the type of fossil fuel which is used. The grouping of power producing units into classes of capacity has been made in accordance with the classification adopted by UNIPEDE/WEC. The definitions in NORDEL's 'Tillgaenglighetsbegrepp foer vaermekraft' ('The Concept of Availability for Thermal Power'), September 1977, are used in this report. The basic data for the availability are in accordance with the recommendations of UNIPEDE/WEC. (author)

A Statistical Model for Uplink Intercell Interference with Power Adaptation and Greedy Scheduling

KAUST Repository

Tabassum, Hina

2012-10-03

This paper deals with the statistical modeling of uplink inter-cell interference (ICI) considering greedy scheduling with power adaptation based on channel conditions. The derived model is implicitly generalized for any kind of shadowing and fading environments. More precisely, we develop a generic model for the distribution of ICI based on the locations of the allocated users and their transmit powers. The derived model is utilized to evaluate important network performance metrics such as ergodic capacity, average fairness and average power preservation numerically. Monte-Carlo simulation details are included to support the analysis and show the accuracy of the derived expressions. In parallel to the literature, we show that greedy scheduling with power adaptation reduces the ICI, average power consumption of users, and enhances the average fairness among users, compared to the case without power adaptation. © 2012 IEEE.

A Statistical Model for Uplink Intercell Interference with Power Adaptation and Greedy Scheduling

KAUST Repository

Tabassum, Hina; Yilmaz, Ferkan; Dawy, Zaher; Alouini, Mohamed-Slim

2012-01-01

This paper deals with the statistical modeling of uplink inter-cell interference (ICI) considering greedy scheduling with power adaptation based on channel conditions. The derived model is implicitly generalized for any kind of shadowing and fading environments. More precisely, we develop a generic model for the distribution of ICI based on the locations of the allocated users and their transmit powers. The derived model is utilized to evaluate important network performance metrics such as ergodic capacity, average fairness and average power preservation numerically. Monte-Carlo simulation details are included to support the analysis and show the accuracy of the derived expressions. In parallel to the literature, we show that greedy scheduling with power adaptation reduces the ICI, average power consumption of users, and enhances the average fairness among users, compared to the case without power adaptation. © 2012 IEEE.

Readability of online patient education materials for velopharyngeal insufficiency.

Science.gov (United States)

Xie, Deborah X; Wang, Ray Y; Chinnadurai, Sivakumar

2018-01-01

Evaluate the readability of online and mobile application health information about velopharyngeal insufficiency (VPI). Top website and mobile application results for search terms "velopharyngeal insufficiency", "velopharyngeal dysfunction", "VPI", and "VPD" were analyzed. Readability was determined using 10 algorithms with Readability Studio Professional Edition (Oleander Software Ltd; Vandalia, OH). Subgroup analysis was performed based on search term and article source - academic hospital, general online resource, peer-reviewed journal, or professional organization. 18 unique articles were identified. Overall mean reading grade level was a 12.89 ± 2.9. The highest reading level among these articles was 15.47-approximately the level of a college senior. Articles from "velopharyngeal dysfunction" had the highest mean reading level (13.73 ± 2.11), above "velopharyngeal insufficiency" (12.30 ± 1.56) and "VPI" (11.66 ± 1.70). Articles from peer-reviewed journals had the highest mean reading level (15.35 ± 2.79), while articles from academic hospitals had the lowest (12.81 ± 1.66). There were statistically significant differences in reading levels between the different search terms (P reading level guidelines, online patient education materials for VPI are disseminated with language too complex for most readers. There is also a lack of VPI-related mobile application data available for patients. Patients will benefit if future updates to websites and disseminated patient information are undertaken with health literacy in mind. Future studies will investigate patient comprehension of these materials. Copyright © 2017 Elsevier B.V. All rights reserved.

A multivariate statistical study on a diversified data gathering system for nuclear power plants

International Nuclear Information System (INIS)

Samanta, P.K.; Teichmann, T.; Levine, M.M.; Kato, W.Y.

1989-02-01

In this report, multivariate statistical methods are presented and applied to demonstrate their use in analyzing nuclear power plant operational data. For analyses of nuclear power plant events, approaches are presented for detecting malfunctions and degradations within the course of the event. At the system level, approaches are investigated as a means of diagnosis of system level performance. This involves the detection of deviations from normal performance of the system. The input data analyzed are the measurable physical parameters, such as steam generator level, pressurizer water level, auxiliary feedwater flow, etc. The study provides the methodology and illustrative examples based on data gathered from simulation of nuclear power plant transients and computer simulation of a plant system performance (due to lack of easily accessible operational data). Such an approach, once fully developed, can be used to explore statistically the detection of failure trends and patterns and prevention of conditions with serious safety implications. 33 refs., 18 figs., 9 tabs

In vivo Comet assay--statistical analysis and power calculations of mice testicular cells.

Science.gov (United States)

Hansen, Merete Kjær; Sharma, Anoop Kumar; Dybdahl, Marianne; Boberg, Julie; Kulahci, Murat

2014-11-01

The in vivo Comet assay is a sensitive method for evaluating DNA damage. A recurrent concern is how to analyze the data appropriately and efficiently. A popular approach is to summarize the raw data into a summary statistic prior to the statistical analysis. However, consensus on which summary statistic to use has yet to be reached. Another important consideration concerns the assessment of proper sample sizes in the design of Comet assay studies. This study aims to identify a statistic suitably summarizing the % tail DNA of mice testicular samples in Comet assay studies. A second aim is to provide curves for this statistic outlining the number of animals and gels to use. The current study was based on 11 compounds administered via oral gavage in three doses to male mice: CAS no. 110-26-9, CAS no. 512-56-1, CAS no. 111873-33-7, CAS no. 79-94-7, CAS no. 115-96-8, CAS no. 598-55-0, CAS no. 636-97-5, CAS no. 85-28-9, CAS no. 13674-87-8, CAS no. 43100-38-5 and CAS no. 60965-26-6. Testicular cells were examined using the alkaline version of the Comet assay and the DNA damage was quantified as % tail DNA using a fully automatic scoring system. From the raw data 23 summary statistics were examined. A linear mixed-effects model was fitted to the summarized data and the estimated variance components were used to generate power curves as a function of sample size. The statistic that most appropriately summarized the within-sample distributions was the median of the log-transformed data, as it most consistently conformed to the assumptions of the statistical model. Power curves for 1.5-, 2-, and 2.5-fold changes of the highest dose group compared to the control group when 50 and 100 cells were scored per gel are provided to aid in the design of future Comet assay studies on testicular cells. Copyright © 2014 Elsevier B.V. All rights reserved.

Production-distribution of electric power in France: 1997-98 statistical data

International Nuclear Information System (INIS)

1999-01-01

This document has been realized using the annual inquiry carried out by the French direction of gas, electricity and coal (Digec). It brings together the main statistical data about the production, transport and consumption of electric power in France: 1997 and 1998 balance sheets, foreign exchanges, long-term evolutions, production with respect to the different energy sources, consumption in the different departments and regions.. (J.S.)

Statistical modeling of the power grid from a wind farm standpoint

DEFF Research Database (Denmark)

Farajzadehbibalan, Saber; Ramezani, Mohammad H.; Nielsen, Peter

2017-01-01

wind farm over several years which results in the development of a useful model for practical purposes. Secondly, the derived model is computationally inexpensive. Considering an arbitrary wind turbine generator, we show that the behavior of the power grid at the connection point can be represented......In this study, we derive a statistical model of a power grid from the wind farm's standpoint based on dynamic principal component analysis. The main advantages of our model compared to the previously developed models are twofold. Firstly, our proposed model benefits from logged data of an offshore...... by 4 out of 9 registered variables, i.e. 3-phase voltages, 3-phase currents, frequency, and generated active and reactive powers. We further prove that the dynamic nature of the system can be optimally captured by a time lag shift of two samples. To extend the derived model of a wind turbine generator...

The MAX Statistic is Less Powerful for Genome Wide Association Studies Under Most Alternative Hypotheses.

Science.gov (United States)

Shifflett, Benjamin; Huang, Rong; Edland, Steven D

2017-01-01

Genotypic association studies are prone to inflated type I error rates if multiple hypothesis testing is performed, e.g., sequentially testing for recessive, multiplicative, and dominant risk. Alternatives to multiple hypothesis testing include the model independent genotypic χ 2 test, the efficiency robust MAX statistic, which corrects for multiple comparisons but with some loss of power, or a single Armitage test for multiplicative trend, which has optimal power when the multiplicative model holds but with some loss of power when dominant or recessive models underlie the genetic association. We used Monte Carlo simulations to describe the relative performance of these three approaches under a range of scenarios. All three approaches maintained their nominal type I error rates. The genotypic χ 2 and MAX statistics were more powerful when testing a strictly recessive genetic effect or when testing a dominant effect when the allele frequency was high. The Armitage test for multiplicative trend was most powerful for the broad range of scenarios where heterozygote risk is intermediate between recessive and dominant risk. Moreover, all tests had limited power to detect recessive genetic risk unless the sample size was large, and conversely all tests were relatively well powered to detect dominant risk. Taken together, these results suggest the general utility of the multiplicative trend test when the underlying genetic model is unknown.

Glottal insufficiency with aspiration risk in dysphagia.

Science.gov (United States)

Giraldez-Rodriguez, Laureano A; Johns, Michael

2013-12-01

Glottal closure is an important part of the mechanism that protects the airway during the normal swallow. Glottal insufficiency disrupts glottal closure and therefore puts patients at risk of aspiration. Treatment of glottal insufficiency can be classified as surgical or nonsurgical. The objective of treating glottal insufficiency is to avoid aspiration or penetration of secretions or food into the airway. Nonsurgical treatment consists of swallowing maneuvers and other measures. Surgical treatment of glottal insufficiency includes injection laryngoplasty, medialization thyroplasty with or without arytenoid adduction or with arytenopexy and cricothyroid subluxation, hypopharyngoplasty, cricopharynx muscle dilation, and cricopharynx myotomy. Copyright © 2013 Elsevier Inc. All rights reserved.

Classification of Underlying Causes of Power Quality Disturbances: Deterministic versus Statistical Methods

Directory of Open Access Journals (Sweden)

Emmanouil Styvaktakis

2007-01-01

Full Text Available This paper presents the two main types of classification methods for power quality disturbances based on underlying causes: deterministic classification, giving an expert system as an example, and statistical classification, with support vector machines (a novel method as an example. An expert system is suitable when one has limited amount of data and sufficient power system expert knowledge; however, its application requires a set of threshold values. Statistical methods are suitable when large amount of data is available for training. Two important issues to guarantee the effectiveness of a classifier, data segmentation, and feature extraction are discussed. Segmentation of a sequence of data recording is preprocessing to partition the data into segments each representing a duration containing either an event or a transition between two events. Extraction of features is applied to each segment individually. Some useful features and their effectiveness are then discussed. Some experimental results are included for demonstrating the effectiveness of both systems. Finally, conclusions are given together with the discussion of some future research directions.

A doppler-based evaluation of peripheral lower limb arterial insufficiency in diabetes mellitus

International Nuclear Information System (INIS)

Shaheen, R.; Sohail, S.

2010-01-01

To determine the frequency, level and flow patterns of lower limb arterial insufficiency in diabetic patients on Doppler ultrasound study. Study Design: Cross-sectional study. Place and Duration of Study: Radiology Department, Civil Hospital, Karachi, from February 2007 to September 2008. Methodology: One hundred adult diabetic patients with suspected peripheral vascular insufficiency irrespective of gender were included. Demographic data, presenting complaints, treatment history, and level of HbA1c were recorded. Doppler evaluated arterial status and ankle brachial index (ABI) were recorded on proforma. Statistical analysis were done on SPSS version 12. Results: The mean HbA1c was 8.4 +- 1.4 gm/dl, a majority of 77% having a controlled level of < 10 mg/dl. Arterial insufficiency on Doppler ultrasound was documented in 62% (p=0.016) and the dorsalis paedis artery was the predominant site of stenosis (24%). Spectral broadening and biphasic flow were salient features. The mean value of resistive index in stenotic cases was 0.563 +- 0.16 with a mean velocity difference of 0.37 +- 0.29 m/s (p < 0.001) at the site of stenosis. Conclusion: Peripheral vascular insufficiency was a significant finding in patients having diabetes for an average of 9.8 years, even in the presence of controlled HbA1c. The dorsalis paedis was the commonest site of involvement. The insufficiency was moderate with a biphasic flow pattern in a majority of cases. Difference in resistive index and flow velocities at and above the site of stenosis provided an important clue to the diagnosis of level of stenosis that helps in planning limb salvage management. (author)

In vivo Comet assay – statistical analysis and power calculations of mice testicular cells

DEFF Research Database (Denmark)

Hansen, Merete Kjær; Sharma, Anoop Kumar; Dybdahl, Marianne

2014-01-01

is to provide curves for this statistic outlining the number of animals and gels to use. The current study was based on 11 compounds administered via oral gavage in three doses to male mice: CAS no. 110-26-9, CAS no. 512-56-1, CAS no. 111873-33-7, CAS no. 79-94-7, CAS no. 115-96-8, CAS no. 598-55-0, CAS no. 636....... A linear mixed-effects model was fitted to the summarized data and the estimated variance components were used to generate power curves as a function of sample size. The statistic that most appropriately summarized the within-sample distributions was the median of the log-transformed data, as it most...... consistently conformed to the assumptions of the statistical model. Power curves for 1.5-, 2-, and 2.5-fold changes of the highest dose group compared to the control group when 50 and 100 cells were scored per gel are provided to aid in the design of future Comet assay studies on testicular cells....

An evaluation of clinical treatment of convergence insufficiency for children with reading difficulties

Directory of Open Access Journals (Sweden)

Dusek Wolfgang A

2011-08-01

Full Text Available Abstract Background The present study investigates two different treatment options for convergence insufficiency CI for a group of children with reading difficulties referred by educational institutes to a specialist eye clinic in Vienna. Methods One hundred and thirty four subjects (aged 7-14 years with reading difficulties were referred from an educational institute in Vienna, Austria for visual assessment. Each child was given either 8Δ base-in reading spectacles (n = 51 or computerised home vision therapy (HTS (n = 51. Thirty two participants refused all treatment offered (clinical control group. A full visual assessment including reading speed and accuracy were conducted pre- and post-treatment. Results Factorial analyses demonstrated statistically significant changes between results obtained for visits 1 and 2 for total reading time, reading error score, amplitude of accommodation and binocular accommodative facility (within subjects effects (p Conclusions Reading difficulties with no apparent intellectual or psychological foundation may be due to a binocular vision anomaly such as convergence insufficiency. Both the HTS and prismatic correction are highly effective treatment options for convergence insufficiency. Prismatic correction can be considered an effective alternative to HTS.

Statistical modeling of an integrated boiler for coal fired thermal power plant.

Science.gov (United States)

Chandrasekharan, Sreepradha; Panda, Rames Chandra; Swaminathan, Bhuvaneswari Natrajan

2017-06-01

The coal fired thermal power plants plays major role in the power production in the world as they are available in abundance. Many of the existing power plants are based on the subcritical technology which can produce power with the efficiency of around 33%. But the newer plants are built on either supercritical or ultra-supercritical technology whose efficiency can be up to 50%. Main objective of the work is to enhance the efficiency of the existing subcritical power plants to compensate for the increasing demand. For achieving the objective, the statistical modeling of the boiler units such as economizer, drum and the superheater are initially carried out. The effectiveness of the developed models is tested using analysis methods like R 2 analysis and ANOVA (Analysis of Variance). The dependability of the process variable (temperature) on different manipulated variables is analyzed in the paper. Validations of the model are provided with their error analysis. Response surface methodology (RSM) supported by DOE (design of experiments) are implemented to optimize the operating parameters. Individual models along with the integrated model are used to study and design the predictive control of the coal-fired thermal power plant.

Reliability and statistical power analysis of cortical and subcortical FreeSurfer metrics in a large sample of healthy elderly.

Science.gov (United States)

Liem, Franziskus; Mérillat, Susan; Bezzola, Ladina; Hirsiger, Sarah; Philipp, Michel; Madhyastha, Tara; Jäncke, Lutz

2015-03-01

FreeSurfer is a tool to quantify cortical and subcortical brain anatomy automatically and noninvasively. Previous studies have reported reliability and statistical power analyses in relatively small samples or only selected one aspect of brain anatomy. Here, we investigated reliability and statistical power of cortical thickness, surface area, volume, and the volume of subcortical structures in a large sample (N=189) of healthy elderly subjects (64+ years). Reliability (intraclass correlation coefficient) of cortical and subcortical parameters is generally high (cortical: ICCs>0.87, subcortical: ICCs>0.95). Surface-based smoothing increases reliability of cortical thickness maps, while it decreases reliability of cortical surface area and volume. Nevertheless, statistical power of all measures benefits from smoothing. When aiming to detect a 10% difference between groups, the number of subjects required to test effects with sufficient power over the entire cortex varies between cortical measures (cortical thickness: N=39, surface area: N=21, volume: N=81; 10mm smoothing, power=0.8, α=0.05). For subcortical regions this number is between 16 and 76 subjects, depending on the region. We also demonstrate the advantage of within-subject designs over between-subject designs. Furthermore, we publicly provide a tool that allows researchers to perform a priori power analysis and sensitivity analysis to help evaluate previously published studies and to design future studies with sufficient statistical power. Copyright © 2014 Elsevier Inc. All rights reserved.

Generation of statistical scenarios of short-term wind power production

DEFF Research Database (Denmark)

Pinson, Pierre; Papaefthymiou, George; Klockl, Bernd

2007-01-01

Short-term (up to 2-3 days ahead) probabilistic forecasts of wind power provide forecast users with a paramount information on the uncertainty of expected wind generation. Whatever the type of these probabilistic forecasts, they are produced on a per horizon basis, and hence do not inform...... on the development of the forecast uncertainty through forecast series. This issue is addressed here by describing a method that permits to generate statistical scenarios of wind generation that accounts for the interdependence structure of prediction errors, in plus of respecting predictive distributions of wind...

The case for increasing the statistical power of eddy covariance ecosystem studies: why, where and how?

Science.gov (United States)

Hill, Timothy; Chocholek, Melanie; Clement, Robert

2017-06-01

Eddy covariance (EC) continues to provide invaluable insights into the dynamics of Earth's surface processes. However, despite its many strengths, spatial replication of EC at the ecosystem scale is rare. High equipment costs are likely to be partially responsible. This contributes to the low sampling, and even lower replication, of ecoregions in Africa, Oceania (excluding Australia) and South America. The level of replication matters as it directly affects statistical power. While the ergodicity of turbulence and temporal replication allow an EC tower to provide statistically robust flux estimates for its footprint, these principles do not extend to larger ecosystem scales. Despite the challenge of spatially replicating EC, it is clearly of interest to be able to use EC to provide statistically robust flux estimates for larger areas. We ask: How much spatial replication of EC is required for statistical confidence in our flux estimates of an ecosystem? We provide the reader with tools to estimate the number of EC towers needed to achieve a given statistical power. We show that for a typical ecosystem, around four EC towers are needed to have 95% statistical confidence that the annual flux of an ecosystem is nonzero. Furthermore, if the true flux is small relative to instrument noise and spatial variability, the number of towers needed can rise dramatically. We discuss approaches for improving statistical power and describe one solution: an inexpensive EC system that could help by making spatial replication more affordable. However, we note that diverting limited resources from other key measurements in order to allow spatial replication may not be optimal, and a balance needs to be struck. While individual EC towers are well suited to providing fluxes from the flux footprint, we emphasize that spatial replication is essential for statistically robust fluxes if a wider ecosystem is being studied. © 2016 The Authors Global Change Biology Published by John Wiley

Statistical annual report 2003 of Furnas - Electrical Power plants and Co., RJ, Brazil. Calendar year 2003

International Nuclear Information System (INIS)

2003-01-01

This document presents the statistical annual report of Furnas Power Plants and Co, reporting the results obtained during the calendar year of 2003 and the evolution in the last five years, allowing a general and comparative views of the company performance focusing the power generation and transmission, economic and financial results

Statistical study of undulator radiated power by a classical detection system in the mm-wave regime

Directory of Open Access Journals (Sweden)

A. Eliran

2009-05-01

Full Text Available The statistics of FEL spontaneous emission power detected with a detector integration time much larger than the slippage time has been measured in many previous works at high frequencies. In such cases the quantum (shot noise generated in the detection process is dominant. We have measured spontaneous emission in the Israeli electrostatic accelerator FEL (EA-FEL operating in the mm-wave lengths. In this regime the detector is based on a diode rectifier for which the detector quantum noise is negligible. The measurements were repeated numerous times in order to create a sample space with sufficient data enabling evaluation of the statistical features of the radiated power. The probability density function of the radiated power was found and its moments were calculated. The results of analytical and numerical models are compared to those obtained in experimental measurements.

Statistical modeling of an integrated boiler for coal fired thermal power plant

Directory of Open Access Journals (Sweden)

Sreepradha Chandrasekharan

2017-06-01

Full Text Available The coal fired thermal power plants plays major role in the power production in the world as they are available in abundance. Many of the existing power plants are based on the subcritical technology which can produce power with the efficiency of around 33%. But the newer plants are built on either supercritical or ultra-supercritical technology whose efficiency can be up to 50%. Main objective of the work is to enhance the efficiency of the existing subcritical power plants to compensate for the increasing demand. For achieving the objective, the statistical modeling of the boiler units such as economizer, drum and the superheater are initially carried out. The effectiveness of the developed models is tested using analysis methods like R2 analysis and ANOVA (Analysis of Variance. The dependability of the process variable (temperature on different manipulated variables is analyzed in the paper. Validations of the model are provided with their error analysis. Response surface methodology (RSM supported by DOE (design of experiments are implemented to optimize the operating parameters. Individual models along with the integrated model are used to study and design the predictive control of the coal-fired thermal power plant. Keywords: Chemical engineering, Applied mathematics

"Insufficient evidence of effectiveness" is not "evidence of no effectiveness:" evaluating computer-based education for patients with severe mental illness.

Science.gov (United States)

Stoltz, Peter; Skärsäter, Ingela; Willman, Ania

2009-01-01

This article reports on commissioned research funded by the Swedish Council of Technology Assessment in Health Care (SBU) and the Swedish Nursing Society (SSF). The objective was to review computer-based education programs. However, as the review produced insufficient evidence of effectiveness, the publication was withheld due to a previous incident where such evidence was misunderstood by Swedish policy and health care decision makers. This article highlights the concept of evidence with regard to the consequences of insufficient evidence of effectiveness being mistaken for evidence of no effectiveness. The aim is also to present a systematic review evaluating a computer-based education program for patients suffering from severe mental illness. Systematic database searches in Medline, CINAHL, PsycINFO and the Cochrane Library identified a total of 131 potentially relevant references. Thereafter, 27 references were retrieved as full-text documents, of which 5 were finally included and co-reviewed by two independent researchers. The review found no decisive evidence of effectiveness regarding computer-based education programs designed to assist persons suffering from severe mental illness. Failing to see the difference between insufficient evidence and evidence of no effectiveness may have unexpected consequences. As a result, practice may be misguided and treatments withheld, which at worse may have harmful consequences for patients. In the end, it is of utmost importance that researchers do good quality research by ensuring statistical power and quality of outcome measurement. For example, this review of computer-based education programs could have revealed effective ways of dealing with severe mental illness if the studies included had been conducted using more sophisticated designs.

THE METHOD OF MANAGEMENT WOMEN WITH ISTHMIC-CERVICAL INSUFFICIENCY

Directory of Open Access Journals (Sweden)

Мария Сергеевна Воронцова

2018-01-01

Full Text Available Isthmic-cervical insufficiency (ICI is one of the most common causes of spontaneous premature births. In II trimester of pregnancy in the structure of miscarriages, the share of ICI accounts for about 40 % of cases. The purpose – evaluate the effectiveness of the complex method of correction of isthmic-cervical insufficiency. Materials and methods. A simple, open, prospective, randomized study was performed on the basis of the City Clinical Perinatal Center in Omsk. Under observation, there were 60 patients aged 18-40 years in gestation period of 13-33 weeks 6 days with a proven diagnosis of «isthmic-cervical insufficiency». The main group included 30 patients who received treatment with a new combined method: the obstetric pessary «CVK», which differs from the analogues by a more anatomical ellipsoidal form and an increased number of perforations to improve the outflow of vaginal secretions in combination with intravaginal injection of micronized progesterone in a dosage of 100 mg 2 times a day and a drug normalizing the biocenosis of the vagina, as a lyophilized culture of lactobacilli L. casei rhamnosus Doderleini in a dosage of 340 mg, 1 capsule intravaginally at night 2 times a week. The comparison group consisted of 30 patients who received treatment: obstetric silicone pessary + micronized progesterone at a dosage of 200 mg per day intravaginally. The outcomes of pregnancy and childbirth were evaluated. Results. The total number of premature births in the main group was 4 (13.3 % compared to 12 (40 % in the comparison group (p = 0,023. Based on the results of the study, a statistically significant reduction in patients with recurrent vaginal flora (p = 0,0001 was obtained and, due to a decrease in this indicator, a general decrease in the number of women with complications of pregnancy was registered (p = 0,019. The conclusion. The proposed method of correction of isthmic-cervical insufficiency is more effective

Development of nuclear power plant online monitoring system using statistical quality control

International Nuclear Information System (INIS)

An, Sang Ha

2006-02-01

Statistical Quality Control techniques have been applied to many aspects of industrial engineering. An application to nuclear power plant maintenance and control is also presented that can greatly improve plant safety. As a demonstration of such an approach, a specific system is analyzed: the reactor coolant pumps (RCP) and the fouling resistance of heat exchanger. This research uses Shewart X-bar, R charts, Cumulative Sum charts (CUSUM), and Sequential Probability Ratio Test (SPRT) to analyze the process for the state of statistical control. And we made Control Chart Analyzer (CCA) to support these analyses that can make a decision of error in process. The analysis shows that statistical process control methods can be applied as an early warning system capable of identifying significant equipment problems well in advance of traditional control room alarm indicators. Such a system would provide operators with enough time to respond to possible emergency situations and thus improve plant safety and reliability

The statistical power to detect cross-scale interactions at macroscales

Science.gov (United States)

Wagner, Tyler; Fergus, C. Emi; Stow, Craig A.; Cheruvelil, Kendra S.; Soranno, Patricia A.

2016-01-01

Macroscale studies of ecological phenomena are increasingly common because stressors such as climate and land-use change operate at large spatial and temporal scales. Cross-scale interactions (CSIs), where ecological processes operating at one spatial or temporal scale interact with processes operating at another scale, have been documented in a variety of ecosystems and contribute to complex system dynamics. However, studies investigating CSIs are often dependent on compiling multiple data sets from different sources to create multithematic, multiscaled data sets, which results in structurally complex, and sometimes incomplete data sets. The statistical power to detect CSIs needs to be evaluated because of their importance and the challenge of quantifying CSIs using data sets with complex structures and missing observations. We studied this problem using a spatially hierarchical model that measures CSIs between regional agriculture and its effects on the relationship between lake nutrients and lake productivity. We used an existing large multithematic, multiscaled database, LAke multiscaled GeOSpatial, and temporal database (LAGOS), to parameterize the power analysis simulations. We found that the power to detect CSIs was more strongly related to the number of regions in the study rather than the number of lakes nested within each region. CSI power analyses will not only help ecologists design large-scale studies aimed at detecting CSIs, but will also focus attention on CSI effect sizes and the degree to which they are ecologically relevant and detectable with large data sets.

Posterior tibial tendon insufficiency results at different stages.

Science.gov (United States)

Deland, Jonathan T; Page, Alexandra; Sung, Il-Hoon; O'Malley, Martin J; Inda, David; Choung, Steven

2006-09-01

The results of surgical treatment of posterior tibial tendon insufficiency (PTTI) may be different at different stages of the disease. No single study has compared the results at different stages. This comparison can be helpful to the patient and physician if the patient asks "What if I wait and the disease progresses, how will my results be different?" A preliminary study comparing results for stage IIa, stage IIb (advanced stage II), and stage III was performed followed by a larger study comparing IIa and IIb with 26 and 22 patients, respectively. American Orthopaedic Foot and Ankle Society (AOFAS) outcome scores as well as radiographs and functional questions were used. Nearly all patients, regardless of stage, felt they were helped by surgical treatment. However, the lowest AOFAS score was in stage III, the most advanced stage investigated in this study. In comparing stage IIa and IIb patients, stage IIb patients had a statistically higher incidence of lateral discomfort. Although statistically significant differences were not found in all comparisons, this study suggests that the results of surgical treatment for PTTI declines with increasing stage or severity of disease.

An Analysis of Decentralized Demand Response as Frequency Control Support under CriticalWind Power Oscillations

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Jorge Villena

2015-11-01

Full Text Available In power systems with high wind energy penetration, the conjunction of wind power fluctuations and power system inertia reduction can lead to large frequency excursions, where the operating reserves of conventional power generation may be insufficient to restore the power balance. With the aim of evaluating the demand-side contribution to frequency control, a complete process to determine critical wind oscillations in power systems with high wind penetration is discussed and described in this paper. This process implies thousands of wind power series simulations, which have been carried out through a validated offshore wind farm model. A large number of different conditions have been taken into account, such as frequency dead bands, the percentages of controllable demand and seasonal factor influence on controllable loads. Relevant results and statistics are also included in the paper.

Simulating European wind power generation applying statistical downscaling to reanalysis data

International Nuclear Information System (INIS)

González-Aparicio, I.; Monforti, F.; Volker, P.; Zucker, A.; Careri, F.; Huld, T.; Badger, J.

2017-01-01

Highlights: •Wind speed spatial resolution highly influences calculated wind power peaks and ramps. •Reduction of wind power generation uncertainties using statistical downscaling. •Publicly available dataset of wind power generation hourly time series at NUTS2. -- Abstract: The growing share of electricity production from solar and mainly wind resources constantly increases the stochastic nature of the power system. Modelling the high share of renewable energy sources – and in particular wind power – crucially depends on the adequate representation of the intermittency and characteristics of the wind resource which is related to the accuracy of the approach in converting wind speed data into power values. One of the main factors contributing to the uncertainty in these conversion methods is the selection of the spatial resolution. Although numerical weather prediction models can simulate wind speeds at higher spatial resolution (up to 1 × 1 km) than a reanalysis (generally, ranging from about 25 km to 70 km), they require high computational resources and massive storage systems: therefore, the most common alternative is to use the reanalysis data. However, local wind features could not be captured by the use of a reanalysis technique and could be translated into misinterpretations of the wind power peaks, ramping capacities, the behaviour of power prices, as well as bidding strategies for the electricity market. This study contributes to the understanding what is captured by different wind speeds spatial resolution datasets, the importance of using high resolution data for the conversion into power and the implications in power system analyses. It is proposed a methodology to increase the spatial resolution from a reanalysis. This study presents an open access renewable generation time series dataset for the EU-28 and neighbouring countries at hourly intervals and at different geographical aggregation levels (country, bidding zone and administrative

Power flow as a complement to statistical energy analysis and finite element analysis

Science.gov (United States)

Cuschieri, J. M.

1987-01-01

Present methods of analysis of the structural response and the structure-borne transmission of vibrational energy use either finite element (FE) techniques or statistical energy analysis (SEA) methods. The FE methods are a very useful tool at low frequencies where the number of resonances involved in the analysis is rather small. On the other hand SEA methods can predict with acceptable accuracy the response and energy transmission between coupled structures at relatively high frequencies where the structural modal density is high and a statistical approach is the appropriate solution. In the mid-frequency range, a relatively large number of resonances exist which make finite element method too costly. On the other hand SEA methods can only predict an average level form. In this mid-frequency range a possible alternative is to use power flow techniques, where the input and flow of vibrational energy to excited and coupled structural components can be expressed in terms of input and transfer mobilities. This power flow technique can be extended from low to high frequencies and this can be integrated with established FE models at low frequencies and SEA models at high frequencies to form a verification of the method. This method of structural analysis using power flo and mobility methods, and its integration with SEA and FE analysis is applied to the case of two thin beams joined together at right angles.

Indoor Soiling Method and Outdoor Statistical Risk Analysis of Photovoltaic Power Plants

Science.gov (United States)

Rajasekar, Vidyashree

This is a two-part thesis. Part 1 presents an approach for working towards the development of a standardized artificial soiling method for laminated photovoltaic (PV) cells or mini-modules. Construction of an artificial chamber to maintain controlled environmental conditions and components/chemicals used in artificial soil formulation is briefly explained. Both poly-Si mini-modules and a single cell mono-Si coupons were soiled and characterization tests such as I-V, reflectance and quantum efficiency (QE) were carried out on both soiled, and cleaned coupons. From the results obtained, poly-Si mini-modules proved to be a good measure of soil uniformity, as any non-uniformity present would not result in a smooth curve during I-V measurements. The challenges faced while executing reflectance and QE characterization tests on poly-Si due to smaller size cells was eliminated on the mono-Si coupons with large cells to obtain highly repeatable measurements. This study indicates that the reflectance measurements between 600-700 nm wavelengths can be used as a direct measure of soil density on the modules. Part 2 determines the most dominant failure modes of field aged PV modules using experimental data obtained in the field and statistical analysis, FMECA (Failure Mode, Effect, and Criticality Analysis). The failure and degradation modes of about 744 poly-Si glass/polymer frameless modules fielded for 18 years under the cold-dry climate of New York was evaluated. Defect chart, degradation rates (both string and module levels) and safety map were generated using the field measured data. A statistical reliability tool, FMECA that uses Risk Priority Number (RPN) is used to determine the dominant failure or degradation modes in the strings and modules by means of ranking and prioritizing the modes. This study on PV power plants considers all the failure and degradation modes from both safety and performance perspectives. The indoor and outdoor soiling studies were jointly

Hypothalamic functions in patients with pituitary insufficiency

NARCIS (Netherlands)

Borgers, A.J.F.

2013-01-01

The main objective of this thesis is to increase our understanding of hypothalamic (dys)function in patients with pituitary insufficiency. This goal is driven by the clinical experience of persisting symptoms in patients adequately treated for pituitary insufficiency. We focus primarily on patients

Application of extended statistical combination of uncertainties methodology for digital nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

In, Wang Ki; Uh, Keun Sun; Chul, Kim Heui [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1995-02-01

A technically more direct statistical combinations of uncertainties methodology, extended SCU (XSCU), was applied to statistically combine the uncertainties associated with the DNBR alarm setpoint and the DNBR trip setpoint of digital nuclear power plants. The modified SCU (MSCU) methodology is currently used as the USNRC approved design methodology to perform the same function. In this report, the MSCU and XSCU methodologies were compared in terms of the total uncertainties and the net margins to the DNBR alarm and trip setpoints. The MSCU methodology resulted in the small total penalties due to a significantly negative bias which are quite large. However the XSCU methodology gave the virtually unbiased total uncertainties. The net margins to the DNBR alarm and trip setpoints by the MSCU methodology agree with those by the XSCU methodology within statistical variations. (Author) 12 refs., 17 figs., 5 tabs.

Adolescent Premature Ovarian Insufficiency Following Human Papillomavirus Vaccination

Directory of Open Access Journals (Sweden)

Deirdre Therese Little MBBS, DRANZCOG, FACRRM

2014-10-01

Full Text Available Three young women who developed premature ovarian insufficiency following quadrivalent human papillomavirus (HPV vaccination presented to a general practitioner in rural New South Wales, Australia. The unrelated girls were aged 16, 16, and 18 years at diagnosis. Each had received HPV vaccinations prior to the onset of ovarian decline. Vaccinations had been administered in different regions of the state of New South Wales and the 3 girls lived in different towns in that state. Each had been prescribed the oral contraceptive pill to treat menstrual cycle abnormalities prior to investigation and diagnosis. Vaccine research does not present an ovary histology report of tested rats but does present a testicular histology report. Enduring ovarian capacity and duration of function following vaccination is unresearched in preclinical studies, clinical and postlicensure studies. Postmarketing surveillance does not accurately represent diagnoses in adverse event notifications and can neither represent unnotified cases nor compare incident statistics with vaccine course administration rates. The potential significance of a case series of adolescents with idiopathic premature ovarian insufficiency following HPV vaccination presenting to a general practice warrants further research. Preservation of reproductive health is a primary concern in the recipient target group. Since this group includes all prepubertal and pubertal young women, demonstration of ongoing, uncompromised safety for the ovary is urgently required. This matter needs to be resolved for the purposes of population health and public vaccine confidence.

A testing procedure for wind turbine generators based on the power grid statistical model

DEFF Research Database (Denmark)

Farajzadehbibalan, Saber; Ramezani, Mohammad Hossein; Nielsen, Peter

2017-01-01

In this study, a comprehensive test procedure is developed to test wind turbine generators with a hardware-in-loop setup. The procedure employs the statistical model of the power grid considering the restrictions of the test facility and system dynamics. Given the model in the latent space...

Power and leadership

DEFF Research Database (Denmark)

Fogsgaard, Morten Kusk; Elmholdt, Claus Westergård

2016-01-01

of this contribution is to emphasize the dynamics of power and leadership relations in organizations. Power is traditionally defined as forms of influence based on the execution of control and sanctions (Hatch 2011; Fogsgaard and Elmholdt 2014). However, in relation to leadership, this definition is insufficient...

Convergence Insufficiency, Accommodative Insufficiency, Visual Symptoms, and Astigmatism in Tohono O'odham Students.

Science.gov (United States)

Davis, Amy L; Harvey, Erin M; Twelker, J Daniel; Miller, Joseph M; Leonard-Green, Tina; Campus, Irene

2016-01-01

Purpose. To determine rate of convergence insufficiency (CI) and accommodative insufficiency (AI) and assess the relation between CI, AI, visual symptoms, and astigmatism in school-age children. Methods. 3rd-8th-grade students completed the Convergence Insufficiency Symptom Survey (CISS) and binocular vision testing with correction if prescribed. Students were categorized by astigmatism magnitude (no/low: <1.00 D, moderate: 1.00 D to <3.00 D, and high: ≥3.00 D), presence/absence of clinical signs of CI and AI, and presence of symptoms. Analyses determine rate of clinical CI and AI and symptomatic CI and AI and assessed the relation between CI, AI, visual symptoms, and astigmatism. Results. In the sample of 484 students (11.67 ± 1.81 years of age), rate of symptomatic CI was 6.2% and symptomatic AI 18.2%. AI was more common in students with CI than without CI. Students with AI only (p = 0.02) and with CI and AI (p = 0.001) had higher symptom scores than students with neither CI nor AI. Moderate and high astigmats were not at increased risk for CI or AI. Conclusions. With-the-rule astigmats are not at increased risk for CI or AI. High comorbidity rates of CI and AI and higher symptoms scores with AI suggest that research is needed to determine symptomatology specific to CI.

Telomere Elongation and Naive Pluripotent Stem Cells Achieved from Telomerase Haplo-Insufficient Cells by Somatic Cell Nuclear Transfer

Directory of Open Access Journals (Sweden)

Li-Ying Sung

2014-12-01

Full Text Available Summary: Haplo-insufficiency of telomerase genes in humans leads to telomere syndromes such as dyskeratosis congenital and idiopathic pulmonary fibrosis. Generation of pluripotent stem cells from telomerase haplo-insufficient donor cells would provide unique opportunities toward the realization of patient-specific stem cell therapies. Recently, pluripotent human embryonic stem cells (ntESCs have been efficiently achieved by somatic cell nuclear transfer (SCNT. We tested the hypothesis that SCNT could effectively elongate shortening telomeres of telomerase haplo-insufficient cells in the ntESCs with relevant mouse models. Indeed, telomeres of telomerase haplo-insufficient (Terc+/− mouse cells are elongated in ntESCs. Moreover, ntESCs derived from Terc+/− cells exhibit naive pluripotency as evidenced by generation of Terc+/− ntESC clone pups by tetraploid embryo complementation, the most stringent test of naive pluripotency. These data suggest that SCNT could offer a powerful tool to reprogram telomeres and to discover the factors for robust restoration of telomeres and pluripotency of telomerase haplo-insufficient somatic cells. : Sung et al. demonstrate in a mouse model that telomeres of telomerase haplo-insufficient cells can be elongated by somatic cell nuclear transfer. Moreover, ntESCs derived from Terc+/− cells exhibit pluripotency evidenced by generation of Terc+/−ntESC clone pups by tetraploid embryo complementation, the most stringent test of naive pluripotency.

Evaluating the statistical power of DNA-based identification, exemplified by 'The missing grandchildren of Argentina'.

Science.gov (United States)

Kling, Daniel; Egeland, Thore; Piñero, Mariana Herrera; Vigeland, Magnus Dehli

2017-11-01

Methods and implementations of DNA-based identification are well established in several forensic contexts. However, assessing the statistical power of these methods has been largely overlooked, except in the simplest cases. In this paper we outline general methods for such power evaluation, and apply them to a large set of family reunification cases, where the objective is to decide whether a person of interest (POI) is identical to the missing person (MP) in a family, based on the DNA profile of the POI and available family members. As such, this application closely resembles database searching and disaster victim identification (DVI). If parents or children of the MP are available, they will typically provide sufficient statistical evidence to settle the case. However, if one must resort to more distant relatives, it is not a priori obvious that a reliable conclusion is likely to be reached. In these cases power evaluation can be highly valuable, for instance in the recruitment of additional family members. To assess the power in an identification case, we advocate the combined use of two statistics: the Probability of Exclusion, and the Probability of Exceedance. The former is the probability that the genotypes of a random, unrelated person are incompatible with the available family data. If this is close to 1, it is likely that a conclusion will be achieved regarding general relatedness, but not necessarily the specific relationship. To evaluate the ability to recognize a true match, we use simulations to estimate exceedance probabilities, i.e. the probability that the likelihood ratio will exceed a given threshold, assuming that the POI is indeed the MP. All simulations are done conditionally on available family data. Such conditional simulations have a long history in medical linkage analysis, but to our knowledge this is the first systematic forensic genetics application. Also, for forensic markers mutations cannot be ignored and therefore current models and

A Statistical Approach to Planning Reserved Electric Power for Railway Infrastructure Administration

OpenAIRE

Brabec, M. (Marek); Pelikán, E. (Emil); Konár, O. (Ondřej); Kasanický, I. (Ivan); Juruš, P. (Pavel); Sadil, J.; Blažek, P.

2013-01-01

One of the requirements on railway infrastructure administration is to provide electricity for day-to-day operation of railways. We propose a statistically based approach for the estimation of maximum 15-minute power within a calendar month for a given region. This quantity serves as a basis of contracts between railway infrastructure administration and electricity distribution system operator. We show that optimization of the prediction is possible, based on underlying loss function deriv...

A new Markov-chain-related statistical approach for modelling synthetic wind power time series

International Nuclear Information System (INIS)

Pesch, T; Hake, J F; Schröders, S; Allelein, H J

2015-01-01

The integration of rising shares of volatile wind power in the generation mix is a major challenge for the future energy system. To address the uncertainties involved in wind power generation, models analysing and simulating the stochastic nature of this energy source are becoming increasingly important. One statistical approach that has been frequently used in the literature is the Markov chain approach. Recently, the method was identified as being of limited use for generating wind time series with time steps shorter than 15–40 min as it is not capable of reproducing the autocorrelation characteristics accurately. This paper presents a new Markov-chain-related statistical approach that is capable of solving this problem by introducing a variable second lag. Furthermore, additional features are presented that allow for the further adjustment of the generated synthetic time series. The influences of the model parameter settings are examined by meaningful parameter variations. The suitability of the approach is demonstrated by an application analysis with the example of the wind feed-in in Germany. It shows that—in contrast to conventional Markov chain approaches—the generated synthetic time series do not systematically underestimate the required storage capacity to balance wind power fluctuation. (paper)

A power comparison of generalized additive models and the spatial scan statistic in a case-control setting

Directory of Open Access Journals (Sweden)

Ozonoff Al

2010-07-01

Full Text Available Abstract Background A common, important problem in spatial epidemiology is measuring and identifying variation in disease risk across a study region. In application of statistical methods, the problem has two parts. First, spatial variation in risk must be detected across the study region and, second, areas of increased or decreased risk must be correctly identified. The location of such areas may give clues to environmental sources of exposure and disease etiology. One statistical method applicable in spatial epidemiologic settings is a generalized additive model (GAM which can be applied with a bivariate LOESS smoother to account for geographic location as a possible predictor of disease status. A natural hypothesis when applying this method is whether residential location of subjects is associated with the outcome, i.e. is the smoothing term necessary? Permutation tests are a reasonable hypothesis testing method and provide adequate power under a simple alternative hypothesis. These tests have yet to be compared to other spatial statistics. Results This research uses simulated point data generated under three alternative hypotheses to evaluate the properties of the permutation methods and compare them to the popular spatial scan statistic in a case-control setting. Case 1 was a single circular cluster centered in a circular study region. The spatial scan statistic had the highest power though the GAM method estimates did not fall far behind. Case 2 was a single point source located at the center of a circular cluster and Case 3 was a line source at the center of the horizontal axis of a square study region. Each had linearly decreasing logodds with distance from the point. The GAM methods outperformed the scan statistic in Cases 2 and 3. Comparing sensitivity, measured as the proportion of the exposure source correctly identified as high or low risk, the GAM methods outperformed the scan statistic in all three Cases. Conclusions The GAM

A power comparison of generalized additive models and the spatial scan statistic in a case-control setting.

Science.gov (United States)

Young, Robin L; Weinberg, Janice; Vieira, Verónica; Ozonoff, Al; Webster, Thomas F

2010-07-19

A common, important problem in spatial epidemiology is measuring and identifying variation in disease risk across a study region. In application of statistical methods, the problem has two parts. First, spatial variation in risk must be detected across the study region and, second, areas of increased or decreased risk must be correctly identified. The location of such areas may give clues to environmental sources of exposure and disease etiology. One statistical method applicable in spatial epidemiologic settings is a generalized additive model (GAM) which can be applied with a bivariate LOESS smoother to account for geographic location as a possible predictor of disease status. A natural hypothesis when applying this method is whether residential location of subjects is associated with the outcome, i.e. is the smoothing term necessary? Permutation tests are a reasonable hypothesis testing method and provide adequate power under a simple alternative hypothesis. These tests have yet to be compared to other spatial statistics. This research uses simulated point data generated under three alternative hypotheses to evaluate the properties of the permutation methods and compare them to the popular spatial scan statistic in a case-control setting. Case 1 was a single circular cluster centered in a circular study region. The spatial scan statistic had the highest power though the GAM method estimates did not fall far behind. Case 2 was a single point source located at the center of a circular cluster and Case 3 was a line source at the center of the horizontal axis of a square study region. Each had linearly decreasing logodds with distance from the point. The GAM methods outperformed the scan statistic in Cases 2 and 3. Comparing sensitivity, measured as the proportion of the exposure source correctly identified as high or low risk, the GAM methods outperformed the scan statistic in all three Cases. The GAM permutation testing methods provide a regression

The influence of the presence of deviant item score patterns on the power of a person-fit statistic

NARCIS (Netherlands)

Meijer, R.R.

1994-01-01

In studies investigating the power of person-fit statistics it is often assumed that the item parameters that are used to calculate the statistics can be estimated in a sample without aberrant persons. However, in practical test applications calibration samples most likely will contain aberrant

Statistical interpretation of transient current power-law decay in colloidal quantum dot arrays

Energy Technology Data Exchange (ETDEWEB)

Sibatov, R T, E-mail: ren_sib@bk.ru [Ulyanovsk State University, 432000, 42 Leo Tolstoy Street, Ulyanovsk (Russian Federation)

2011-08-01

A new statistical model of the charge transport in colloidal quantum dot arrays is proposed. It takes into account Coulomb blockade forbidding multiple occupancy of nanocrystals and the influence of energetic disorder of interdot space. The model explains power-law current transients and the presence of the memory effect. The fractional differential analogue of the Ohm law is found phenomenologically for nanocrystal arrays. The model combines ideas that were considered as conflicting by other authors: the Scher-Montroll idea about the power-law distribution of waiting times in localized states for disordered semiconductors is applied taking into account Coulomb blockade; Novikov's condition about the asymptotic power-law distribution of time intervals between successful current pulses in conduction channels is fulfilled; and the carrier injection blocking predicted by Ginger and Greenham (2000 J. Appl. Phys. 87 1361) takes place.

Statistical interpretation of transient current power-law decay in colloidal quantum dot arrays

International Nuclear Information System (INIS)

Sibatov, R T

2011-01-01

A new statistical model of the charge transport in colloidal quantum dot arrays is proposed. It takes into account Coulomb blockade forbidding multiple occupancy of nanocrystals and the influence of energetic disorder of interdot space. The model explains power-law current transients and the presence of the memory effect. The fractional differential analogue of the Ohm law is found phenomenologically for nanocrystal arrays. The model combines ideas that were considered as conflicting by other authors: the Scher-Montroll idea about the power-law distribution of waiting times in localized states for disordered semiconductors is applied taking into account Coulomb blockade; Novikov's condition about the asymptotic power-law distribution of time intervals between successful current pulses in conduction channels is fulfilled; and the carrier injection blocking predicted by Ginger and Greenham (2000 J. Appl. Phys. 87 1361) takes place.

Spreadsheets as tools for statistical computing and statistics education

OpenAIRE

Neuwirth, Erich

2000-01-01

Spreadsheets are an ubiquitous program category, and we will discuss their use in statistics and statistics education on various levels, ranging from very basic examples to extremely powerful methods. Since the spreadsheet paradigm is very familiar to many potential users, using it as the interface to statistical methods can make statistics more easily accessible.

Impact of insufficient energy content in the design time history on the structure response

International Nuclear Information System (INIS)

Ma, D.C.; Gvildys, J.; Chang, Y.W.; Seidensticker, R.W.

1989-01-01

In the design of nuclear power plants, it is often desirable to use the time history method in the soil-structure interaction analysis to determine the plant floor response to seismic loads. Because many design criteria are specified in terms of design response spectra, the artificial time history needs to be generated under the requirement that the response spectra of the artificial history should envelop the given design response spectra. However, recent studies indicate that the artificial time history used in the plant design may have insufficient energy in the frequency range of interest, even though the response spectra of the design time history closely envelop the design response spectra. This paper presents an investigation of the effects of the insufficient energy content in the design time history on the response of the soil-structure system. Numerical studies were carried out. Both the real earthquake records and the artificial time histories were used as the input motions in a simple lumped-mass soil-structure interaction model. The results obtained from this study provide a better understanding of the effects of the insufficient energy content in the design time history on the structural response

Impact of insufficient energy content in the design time history on the structure response

International Nuclear Information System (INIS)

Ma, D.C.; Gvildys, J.; Chang, Y.W.; Seidensticker, R.W.

1989-01-01

In the design of nuclear power plants, it is often desirable to use the time history method in the soil-structure interaction analysis to determine the plant floor response to seismic loads. Because many design criteria are specified in terms of design response spectra, the artificial time history needs to be generated under the requirement that the response spectra of the artificial history should envelop the given design response spectra. However, recent studies indicate that the artificial time history used in the plant design may have insufficient energy in the frequency range of interest, even though the response spectra of the design time history closely envelop the design response spectra. Therefore, the proposed changes in the NRC Standard Review Plan requires that when a single time history is used in the seismic design, it must satisfy requirements for both response spectra enveloping and matching a power spectra density (PSD) function in the frequency range of interest. The use of multiple artificial time histories (at least five time histories) in the plant design is also suggested in the new Standard Review Plan. This paper presents an investigation of the effects of the insufficient energy content in the design time history on the response of the soil-structure system. Numerical studies were carried out. Both the real earthquake records and the artificial time histories were used as the input motions in a simple lumped-mass soil-structure interaction model. The results obtained from this study provide a better understanding of the effects of the insufficient energy content in the design time history on the structural response. 5 refs., 10 figs., 1 tab

Powerful Inference with the D-Statistic on Low-Coverage Whole-Genome Data.

Science.gov (United States)

Soraggi, Samuele; Wiuf, Carsten; Albrechtsen, Anders

2018-02-02

The detection of ancient gene flow between human populations is an important issue in population genetics. A common tool for detecting ancient admixture events is the D-statistic. The D-statistic is based on the hypothesis of a genetic relationship that involves four populations, whose correctness is assessed by evaluating specific coincidences of alleles between the groups. When working with high-throughput sequencing data, calling genotypes accurately is not always possible; therefore, the D-statistic currently samples a single base from the reads of one individual per population. This implies ignoring much of the information in the data, an issue especially striking in the case of ancient genomes. We provide a significant improvement to overcome the problems of the D-statistic by considering all reads from multiple individuals in each population. We also apply type-specific error correction to combat the problems of sequencing errors, and show a way to correct for introgression from an external population that is not part of the supposed genetic relationship, and how this leads to an estimate of the admixture rate. We prove that the D-statistic is approximated by a standard normal distribution. Furthermore, we show that our method outperforms the traditional D-statistic in detecting admixtures. The power gain is most pronounced for low and medium sequencing depth (1-10×), and performances are as good as with perfectly called genotypes at a sequencing depth of 2×. We show the reliability of error correction in scenarios with simulated errors and ancient data, and correct for introgression in known scenarios to estimate the admixture rates. Copyright © 2018 Soraggi et al.

Hysteresis and Power-Law Statistics during temperature induced martensitic transformation

International Nuclear Information System (INIS)

Paul, Arya; Sengupta, Surajit; Rao, Madan

2011-01-01

We study hysteresis in temperature induced martensitic transformation using a 2D model solid exhibiting a square to rhombic structural transition. We find that upon quenching, the high temperature square phase, martensites are nucleated at sites having large non-affineness and ultimately invades the whole of the high temperature square phase. On heating the martensite, the high temperature square phase is restored. The transformation proceeds through avalanches. The amplitude and the time-duration of these avalanches exhibit power-law statistics both during heating and cooling of the system. The exponents corresponding to heating and cooling are different thereby indicating that the nucleation and dissolution of the product phase follows different transformation mechanism.

Power analysis as a tool to identify statistically informative indicators for monitoring coral reef disturbances.

Science.gov (United States)

Van Wynsberge, Simon; Gilbert, Antoine; Guillemot, Nicolas; Heintz, Tom; Tremblay-Boyer, Laura

2017-07-01

Extensive biological field surveys are costly and time consuming. To optimize sampling and ensure regular monitoring on the long term, identifying informative indicators of anthropogenic disturbances is a priority. In this study, we used 1800 candidate indicators by combining metrics measured from coral, fish, and macro-invertebrate assemblages surveyed from 2006 to 2012 in the vicinity of an ongoing mining project in the Voh-Koné-Pouembout lagoon, New Caledonia. We performed a power analysis to identify a subset of indicators which would best discriminate temporal changes due to a simulated chronic anthropogenic impact. Only 4% of tested indicators were likely to detect a 10% annual decrease of values with sufficient power (>0.80). Corals generally exerted higher statistical power than macro-invertebrates and fishes because of lower natural variability and higher occurrence. For the same reasons, higher taxonomic ranks provided higher power than lower taxonomic ranks. Nevertheless, a number of families of common sedentary or sessile macro-invertebrates and fishes also performed well in detecting changes: Echinometridae, Isognomidae, Muricidae, Tridacninae, Arcidae, and Turbinidae for macro-invertebrates and Pomacentridae, Labridae, and Chaetodontidae for fishes. Interestingly, these families did not provide high power in all geomorphological strata, suggesting that the ability of indicators in detecting anthropogenic impacts was closely linked to reef geomorphology. This study provides a first operational step toward identifying statistically relevant indicators of anthropogenic disturbances in New Caledonia's coral reefs, which can be useful in similar tropical reef ecosystems where little information is available regarding the responses of ecological indicators to anthropogenic disturbances.

WATER POLO GAME-RELATED STATISTICS IN WOMEN'S INTERNATIONAL CHAMPIONSHIPS: DIFFERENCES AND DISCRIMINATORY POWER

Directory of Open Access Journals (Sweden)

Yolanda Escalante

2012-09-01

Full Text Available The aims of this study were (i to compare women's water polo game-related statistics by match outcome (winning and losing teams and phase (preliminary, classificatory, and semi-final/bronze medal/gold medal, and (ii identify characteristics that discriminate performances for each phase. The game-related statistics of the 124 women's matches played in five International Championships (World and European Championships were analyzed. Differences between winning and losing teams in each phase were determined using the chi-squared. A discriminant analysis was then performed according to context in each of the three phases. It was found that the game-related statistics differentiate the winning from the losing teams in each phase of an international championship. The differentiating variables were both offensive (centre goals, power-play goals, counterattack goal, assists, offensive fouls, steals, blocked shots, and won sprints and defensive (goalkeeper-blocked shots, goalkeeper-blocked inferiority shots, and goalkeeper-blocked 5-m shots. The discriminant analysis showed the game-related statistics to discriminate performance in all phases: preliminary, classificatory, and final phases (92%, 90%, and 83%, respectively. Two variables were discriminatory by match outcome (winning or losing teams in all three phases: goals and goalkeeper-blocked shots

Food insufficiency and food insecurity as risk factors for physical disability among Palestinian refugees in Lebanon: Evidence from an observational study.

Science.gov (United States)

Salti, Nisreen; Ghattas, Hala

2016-10-01

Potential interactions between malnutrition and disability are increasingly recognized, and both are important global health issues. Causal effects working from nutrition to disability and from disability back to nutrition present an empirical challenge to measuring either of these effects. However, disability affects nutrition whatever the cause of disability, whereas nutrition is likelier to affect disease-related disability than war- or work-related disability. This paper investigates the association of food insufficiency with the risk of physical disability. Data on disability by cause allow us to address the difficulty of reverse causality. Multinomial logit regressions of disability by cause on food insufficiency are run using survey data from 2010 on 2575 Palestinian refugee households in Lebanon. Controls include household sociodemographic, health and economic characteristics. Regressions of food insufficiency on disability by cause are also run. Disability has a significant coefficient in regressions of food insufficiency, whatever the cause of disability; but in regressions of disability on food insufficiency, food insufficiency is significant only for disease-related disability (log odds of disease-related disability .78 higher, p = .008). The difference in the results by cause of disability is evidence of a significant association between food insufficiency and disease-related disability, net of any reverse effect from disability to food access. The association between disease-related disability and food insufficiency is statistically significant suggesting that even taking into account feedback from disability to nutrition, nutrition is an effective level of intervention to avert the poverty-disability trap resulting from the impoverishing effect of disability. Copyright © 2016 Elsevier Inc. All rights reserved.

Pancreatic Exocrine Insufficiency in Pancreatic Cancer

Directory of Open Access Journals (Sweden)

Miroslav Vujasinovic

2017-02-01

Full Text Available Abstract: Cancer patients experience weight loss for a variety of reasons, commencing with the tumor’s metabolism (Warburg effect and proceeding via cachexia to loss of appetite. In pancreatic cancer, several other factors are involved, including a loss of appetite with a particular aversion to meat and the incapacity of the pancreatic gland to function normally when a tumor is present in the pancreatic head. Pancreatic exocrine insufficiency is characterized by a deficiency of the enzymes secreted from the pancreas due to the obstructive tumor, resulting in maldigestion. This, in turn, contributes to malnutrition, specifically a lack of fat-soluble vitamins, antioxidants, and other micronutrients. Patients with pancreatic cancer and pancreatic exocrine insufficiency have, overall, an extremely poor prognosis with regard to surgical outcome and overall survival. Therefore, it is crucial to be aware of the mechanisms involved in the disease, to be able to diagnose pancreatic exocrine insufficiency early on, and to treat malnutrition appropriately, for example, with pancreatic enzymes.

Pancreatic Exocrine Insufficiency in Pancreatic Cancer.

Science.gov (United States)

Vujasinovic, Miroslav; Valente, Roberto; Del Chiaro, Marco; Permert, Johan; Löhr, J-Matthias

2017-02-23

Abstract : Cancer patients experience weight loss for a variety of reasons, commencing with the tumor's metabolism (Warburg effect) and proceeding via cachexia to loss of appetite. In pancreatic cancer, several other factors are involved, including a loss of appetite with a particular aversion to meat and the incapacity of the pancreatic gland to function normally when a tumor is present in the pancreatic head. Pancreatic exocrine insufficiency is characterized by a deficiency of the enzymes secreted from the pancreas due to the obstructive tumor, resulting in maldigestion. This, in turn, contributes to malnutrition, specifically a lack of fat-soluble vitamins, antioxidants, and other micronutrients. Patients with pancreatic cancer and pancreatic exocrine insufficiency have, overall, an extremely poor prognosis with regard to surgical outcome and overall survival. Therefore, it is crucial to be aware of the mechanisms involved in the disease, to be able to diagnose pancreatic exocrine insufficiency early on, and to treat malnutrition appropriately, for example, with pancreatic enzymes.

Thirty-day outcomes underestimate endocrine and exocrine insufficiency after pancreatic resection.

Science.gov (United States)

Lim, Pei-Wen; Dinh, Kate H; Sullivan, Mary; Wassef, Wahid Y; Zivny, Jaroslav; Whalen, Giles F; LaFemina, Jennifer

2016-04-01

Long-term incidence of endocrine and exocrine insufficiency after pancreatectomy is poorly described. We analyze the long-term risks of pancreatic insufficiency after pancreatectomy. Subjects who underwent pancreatectomy from 2002 to 2012 were identified from a prospective database (n = 227). Subjects who underwent total pancreatectomy or pancreatitis surgery were excluded. New post-operative endocrine and exocrine insufficiency was defined as the need for new pharmacologic intervention within 1000 days from resection. 28 (16%) of 178 subjects without pre-existing endocrine insufficiency developed post-operative endocrine insufficiency: 7 (25%) did so within 30 days, 8 (29%) between 30 and 90 days, and 13 (46%) after 90 days. 94 (43%) of 214 subjects without pre-operative exocrine insufficiency developed exocrine insufficiency: 20 (21%) did so within 30 days, 29 (31%) between 30 and 90 days, and 45 (48%) after 90 days. Adjuvant radiation was associated with new endocrine insufficiency. On multivariate regression, pancreaticoduodenectomy and chemotherapy were associated with a greater risk of exocrine insufficiency. Reporting 30-day functional outcomes for pancreatic resection is insufficient, as nearly 45% of subjects who develop disease do so after 90 days. Reporting of at least 90-day outcomes may more reliably assess risk for post-operative endocrine and exocrine insufficiency. Copyright © 2016 International Hepato-Pancreato-Biliary Association Inc. Published by Elsevier Ltd. All rights reserved.

MRI of occult sacral insufficiency fractures following radiotherapy

International Nuclear Information System (INIS)

Mammone, J.F.; Schweitzer, M.E.

1995-01-01

Following radiation therapy, marrow abnormalities noted on magnetic resonance imaging (MRI) are frequent and may mimic metastases. Specific radiotherapy changes are usually easily identifiable; however, traumatic lesions cause more interpretive difficulties. We assessed the incidence and MRI characteristics of insufficiency fractures in this population. During a 5-year span (1987-1991), 546 patients received pelvic radiotherapy for primary malignancies. MRI was performed in 25 of these patients at least 3 months after treatment. The mean dose in this group was 53 Gy. These MRI scans were retrospectively reviewed for the appearance of the sacrum with particular attention to the presence of insufficiency fractures. This was correlated with clinical course and scintigraphic findings. Presumed insufficiency fractures on MRI paralleled the sacral side of the sacroiliac joint, enhanced with Gd-DTPA, were most prominent or initially seen anteriorly, and had ill-defined margins on all imaging sequences. The incidence of occult sacral insufficiency fractures was at least 20%. Insufficiency fractures of the sacrum in the post-radiotherapy patient are a relatively frequent occurrence which can mimic metastases. Consideration of this phenomenon and knowledge of differential features may avoid overdiagnosis of osseous metastases. (orig.)

Comparison and validation of statistical methods for predicting power outage durations in the event of hurricanes.

Science.gov (United States)

Nateghi, Roshanak; Guikema, Seth D; Quiring, Steven M

2011-12-01

This article compares statistical methods for modeling power outage durations during hurricanes and examines the predictive accuracy of these methods. Being able to make accurate predictions of power outage durations is valuable because the information can be used by utility companies to plan their restoration efforts more efficiently. This information can also help inform customers and public agencies of the expected outage times, enabling better collective response planning, and coordination of restoration efforts for other critical infrastructures that depend on electricity. In the long run, outage duration estimates for future storm scenarios may help utilities and public agencies better allocate risk management resources to balance the disruption from hurricanes with the cost of hardening power systems. We compare the out-of-sample predictive accuracy of five distinct statistical models for estimating power outage duration times caused by Hurricane Ivan in 2004. The methods compared include both regression models (accelerated failure time (AFT) and Cox proportional hazard models (Cox PH)) and data mining techniques (regression trees, Bayesian additive regression trees (BART), and multivariate additive regression splines). We then validate our models against two other hurricanes. Our results indicate that BART yields the best prediction accuracy and that it is possible to predict outage durations with reasonable accuracy. © 2011 Society for Risk Analysis.

Prevalence of Convergence Insufficiency-Type Symptomatology in Parkinson's Disease.

Science.gov (United States)

Law, Caroline; Chriqui, Estefania; Kergoat, Marie-Jeanne; Leclerc, Bernard-Simon; Panisset, Michel; Irving, Elizabeth L; Postuma, Ronald B; Chouinard, Sylvain; Kergoat, Hélène

2017-09-01

Individuals with Parkinson's disease (PD) often present with visual symptoms (e.g., difficulty in reading, double vision) that can also be found in convergence insufficiency (CI). Our objective was to estimate the prevalence of CI-type visual symptomatology in individuals with PD, in comparison with controls. Participants ≥50 years with (n=300) and without (n=300) PD were recruited. They were administered the Convergence Insufficiency Symptom Survey (CISS-15) over the phone. A score of ≥21 on the CISS-15, considered positive for CI-type symptomatology, served as the cutoff. Data from individuals (n=87 with, n=94 without PD) who were approached but who reported having a known oculovisual condition were analysed separately. Student's t test and chi-square at the 0.05 level were employed for statistical significance. A total of 29.3% of participants with versus 7.3% without PD presented with a score of ≥21 on the CISS-15 (p=0.001). Of the participants having a known oculovisual condition, 39.1% with versus 19.1% without PD presented with a score of ≥21 on the CISS-15 (p=0.01). The prevalence of CI-type visual symptoms is higher in individuals with versus without PD whether or not they have a coexisting oculovisual condition. These results suggest that PD per se places individuals with the disease at greater risk of visual symptomatology. These results further underline the importance of providing regular eye exams for individuals with PD.

From probabilistic forecasts to statistical scenarios of short-term wind power production

DEFF Research Database (Denmark)

Pinson, Pierre; Papaefthymiou, George; Klockl, Bernd

2009-01-01

on the development of the forecast uncertainty through forecast series. However, this additional information may be paramount for a large class of time-dependent and multistage decision-making problems, e.g. optimal operation of combined wind-storage systems or multiple-market trading with different gate closures......Short-term (up to 2-3 days ahead) probabilistic forecasts of wind power provide forecast users with highly valuable information on the uncertainty of expected wind generation. Whatever the type of these probabilistic forecasts, they are produced on a per horizon basis, and hence do not inform....... This issue is addressed here by describing a method that permits the generation of statistical scenarios of short-term wind generation that accounts for both the interdependence structure of prediction errors and the predictive distributions of wind power production. The method is based on the conversion...

Improved statistical power with a sparse shape model in detecting an aging effect in the hippocampus and amygdala

Science.gov (United States)

Chung, Moo K.; Kim, Seung-Goo; Schaefer, Stacey M.; van Reekum, Carien M.; Peschke-Schmitz, Lara; Sutterer, Matthew J.; Davidson, Richard J.

2014-03-01

The sparse regression framework has been widely used in medical image processing and analysis. However, it has been rarely used in anatomical studies. We present a sparse shape modeling framework using the Laplace- Beltrami (LB) eigenfunctions of the underlying shape and show its improvement of statistical power. Tradition- ally, the LB-eigenfunctions are used as a basis for intrinsically representing surface shapes as a form of Fourier descriptors. To reduce high frequency noise, only the first few terms are used in the expansion and higher frequency terms are simply thrown away. However, some lower frequency terms may not necessarily contribute significantly in reconstructing the surfaces. Motivated by this idea, we present a LB-based method to filter out only the significant eigenfunctions by imposing a sparse penalty. For dense anatomical data such as deformation fields on a surface mesh, the sparse regression behaves like a smoothing process, which will reduce the error of incorrectly detecting false negatives. Hence the statistical power improves. The sparse shape model is then applied in investigating the influence of age on amygdala and hippocampus shapes in the normal population. The advantage of the LB sparse framework is demonstrated by showing the increased statistical power.

SeDA: A software package for the statistical analysis of the instrument drift

International Nuclear Information System (INIS)

Lee, H. J.; Jang, S. C.; Lim, T. J.

2006-01-01

The setpoints for safety-related equipment are affected by many sources of an uncertainty. ANSI/ISA-S67.04.01-2000 [1] and ISA-RP6 7.04.02-2000 [2] suggested the statistical approaches for ensuring that the safety-related instrument setpoints were established and maintained within the technical specification limits [3]. However, Jang et al. [4] indicated that the preceding methodologies for a setpoint drift analysis might be insufficient to manage a setpoint drift on an instrumentation device and proposed new statistical analysis procedures for the management of a setpoint drift, based on the plant specific as-found/as-left data. Although IHPA (Instrument History Performance Analysis) is a widely known commercial software package to analyze an instrument setpoint drift, several steps in the new procedure cannot be performed by using it because it is based on the statistical approaches suggested in the ANSI/ISA-S67.04.01 -2000 [1] and ISA-RP67.04.02-2000 [2], In this paper we present a software package (SeDA: Setpoint Drift Analysis) that implements new methodologies, and which is easy to use, as it is accompanied by powerful graphical tools. (authors)

Statistical analysis about corrosion in nuclear power plants

International Nuclear Information System (INIS)

Naquid G, C.; Medina F, A.; Zamora R, L.

1999-01-01

Nowadays, it has been carried out the investigations related with the structure degradation mechanisms, systems or and components in the nuclear power plants, since a lot of the involved processes are the responsible of the reliability of these ones, of the integrity of their components, of the safety aspects and others. This work presents the statistics of the studies related with materials corrosion in its wide variety and specific mechanisms. These exist at world level in the PWR, BWR, and WWER reactors, analysing the AIRS (Advanced Incident Reporting System) during the period between 1993-1998 in the two first plants in during the period between 1982-1995 for the WWER. The factors identification allows characterize them as those which apply, they are what have happen by the presence of some corrosion mechanism. Those which not apply, these are due to incidental by natural factors, mechanical failures and human errors. Finally, the total number of cases analysed, they correspond to the total cases which apply and not apply. (Author)

A statistical model of uplink inter-cell interference with slow and fast power control mechanisms

KAUST Repository

Tabassum, Hina; Yilmaz, Ferkan; Dawy, Zaher; Alouini, Mohamed-Slim

2013-01-01

Uplink power control is in essence an interference mitigation technique that aims at minimizing the inter-cell interference (ICI) in cellular networks by reducing the transmit power levels of the mobile users while maintaining their target received signal quality levels at base stations. Power control mechanisms directly impact the interference dynamics and, thus, affect the overall achievable capacity and consumed power in cellular networks. Due to the stochastic nature of wireless channels and mobile users' locations, it is important to derive theoretical models for ICI that can capture the impact of design alternatives related to power control mechanisms. To this end, we derive and verify a novel statistical model for uplink ICI in Generalized-K composite fading environments as a function of various slow and fast power control mechanisms. The derived expressions are then utilized to quantify numerically key network performance metrics that include average resource fairness, average reduction in power consumption, and ergodic capacity. The accuracy of the derived expressions is validated via Monte-Carlo simulations. Results are generated for multiple network scenarios, and insights are extracted to assess various power control mechanisms as a function of system parameters. © 1972-2012 IEEE.

A statistical model of uplink inter-cell interference with slow and fast power control mechanisms

KAUST Repository

Tabassum, Hina

2013-09-01

Uplink power control is in essence an interference mitigation technique that aims at minimizing the inter-cell interference (ICI) in cellular networks by reducing the transmit power levels of the mobile users while maintaining their target received signal quality levels at base stations. Power control mechanisms directly impact the interference dynamics and, thus, affect the overall achievable capacity and consumed power in cellular networks. Due to the stochastic nature of wireless channels and mobile users\\' locations, it is important to derive theoretical models for ICI that can capture the impact of design alternatives related to power control mechanisms. To this end, we derive and verify a novel statistical model for uplink ICI in Generalized-K composite fading environments as a function of various slow and fast power control mechanisms. The derived expressions are then utilized to quantify numerically key network performance metrics that include average resource fairness, average reduction in power consumption, and ergodic capacity. The accuracy of the derived expressions is validated via Monte-Carlo simulations. Results are generated for multiple network scenarios, and insights are extracted to assess various power control mechanisms as a function of system parameters. © 1972-2012 IEEE.

Theoretical remarks on the statistics of three discriminants in Piety's automated signature analysis of PSD [Power Spectral Density] data

International Nuclear Information System (INIS)

Behringer, K.; Spiekerman, G.

1984-01-01

Piety (1977) proposed an automated signature analysis of power spectral density data. Eight statistical decision discriminants are introduced. For nearly all the discriminants, improved confidence statements can be made. The statistical characteristics of the last three discriminants, which are applications of non-parametric tests, are considered. (author)

Bias, precision and statistical power of analysis of covariance in the analysis of randomized trials with baseline imbalance: a simulation study

Science.gov (United States)

2014-01-01

Background Analysis of variance (ANOVA), change-score analysis (CSA) and analysis of covariance (ANCOVA) respond differently to baseline imbalance in randomized controlled trials. However, no empirical studies appear to have quantified the differential bias and precision of estimates derived from these methods of analysis, and their relative statistical power, in relation to combinations of levels of key trial characteristics. This simulation study therefore examined the relative bias, precision and statistical power of these three analyses using simulated trial data. Methods 126 hypothetical trial scenarios were evaluated (126 000 datasets), each with continuous data simulated by using a combination of levels of: treatment effect; pretest-posttest correlation; direction and magnitude of baseline imbalance. The bias, precision and power of each method of analysis were calculated for each scenario. Results Compared to the unbiased estimates produced by ANCOVA, both ANOVA and CSA are subject to bias, in relation to pretest-posttest correlation and the direction of baseline imbalance. Additionally, ANOVA and CSA are less precise than ANCOVA, especially when pretest-posttest correlation ≥ 0.3. When groups are balanced at baseline, ANCOVA is at least as powerful as the other analyses. Apparently greater power of ANOVA and CSA at certain imbalances is achieved in respect of a biased treatment effect. Conclusions Across a range of correlations between pre- and post-treatment scores and at varying levels and direction of baseline imbalance, ANCOVA remains the optimum statistical method for the analysis of continuous outcomes in RCTs, in terms of bias, precision and statistical power. PMID:24712304

Autoimmune polyglandular syndrome type 3 (APS-3) among patients with premature ovarian insufficiency (POI).

Science.gov (United States)

Szlendak-Sauer, Katarzyna; Jakubik, Daniel; Kunicki, Michał; Skórska, Jolanta; Smolarczyk, Roman

2016-08-01

Autoimmune polyglandular syndrome type 3 - (APS-3), is defined as the coexistence of autoimmune thyroiditis with other non-ovarian autoimmune diseases without primary adrenal insufficiency. Additionally the definition of APS-3 also includes primary ovarian insufficiency (POI) coexistence with autoimmune thyroiditis. The main goal of that study is to assess the prevalence of APS-3 defined as coexistence of autoimmune thyroiditis with POI in population of 46 XX karyotype women with primary ovarian insufficiency (POI). The second goal is to investigate hormonal profile and insulin sensitivity in women with POI and subgroups of women with APS-3 - POI/APS-3(+) and without APS 3 - POI/APS-3(-). Anthropometric measurements, coexistence of autoimmune diseases, androgens, fasting glucose and insulin, glucose and insulin at 60' and 120' of oral glucose tolerance test (OGTT) and homeostasis model for insulin resistance (HOMA-IR), were determine in 98 patients aged between 18 and 39 with spontaneous 46 XX primary ovarian insufficiency (POI), in 33 POI/APS-3(+), 65 POI/APS-3(-), and 75 healthy controls. Continuous data were summarized by the mean±standard deviation (SD), and categorical data by number (percentages). Data were checked for normality using Shapiro-Wilk test, the comparison between groups were performed using non-parametric Mann-Whitney or Kruskall-Wallis test. Pearson's correlation coefficient was used to assess the relationships between parameters. Statistical significance was defined as p values APS-3(+) and POI/APS-3(-) showed significantly lower serum androgens in comparison to controls. Additionally women with POI/APS-3(+) showed hyperinsulinemia after 1h of OGTT; No significant differences in serum fasting glucose, insulin and during 2h OGTT between groups were observed. The prevalence of APS-3 is 33.7% in patients with spontaneous 46 XX primary ovarian insufficiency. Women with POI, POI/APS-3(+) and POI/APS-3(-) feature lower testosterone, androstendione

Statistical learning: a powerful mechanism that operates by mere exposure.

Science.gov (United States)

Aslin, Richard N

2017-01-01

How do infants learn so rapidly and with little apparent effort? In 1996, Saffran, Aslin, and Newport reported that 8-month-old human infants could learn the underlying temporal structure of a stream of speech syllables after only 2 min of passive listening. This demonstration of what was called statistical learning, involving no instruction, reinforcement, or feedback, led to dozens of confirmations of this powerful mechanism of implicit learning in a variety of modalities, domains, and species. These findings reveal that infants are not nearly as dependent on explicit forms of instruction as we might have assumed from studies of learning in which children or adults are taught facts such as math or problem solving skills. Instead, at least in some domains, infants soak up the information around them by mere exposure. Learning and development in these domains thus appear to occur automatically and with little active involvement by an instructor (parent or teacher). The details of this statistical learning mechanism are discussed, including how exposure to specific types of information can, under some circumstances, generalize to never-before-observed information, thereby enabling transfer of learning. WIREs Cogn Sci 2017, 8:e1373. doi: 10.1002/wcs.1373 For further resources related to this article, please visit the WIREs website. © 2016 Wiley Periodicals, Inc.

Long-term follow-up of acute isolated accommodation insufficiency.

Science.gov (United States)

Lee, Jung Jin; Baek, Seung-Hee; Kim, Ungsoo Samuel

2013-04-01

To define the long-term results of accommodation insufficiency and to investigate the correlation between accommodation insufficiency and other factors including near point of convergence (NPC), age, and refractive errors. From January 2008 to December 2009, 11 patients with acute near vision disturbance and remote near point of accommodation (NPA) were evaluated. Full ophthalmologic examinations, including best corrected visual acuity, manifest refraction and prism cover tests were performed. Accommodation ability was measured by NPA using the push-up method. We compared accommodation insufficiency and factors including age, refractive errors and NPC. We also investigated the recovery from loss of accommodation in patients. Mean age of patients was 20 years (range, 9 to 34 years). Five of the 11 patients were female. Mean refractive error was -0.6 diopters (range, -3.5 to +0.25 diopters) and 8 of 11 patients (73%) had emmetropia (+0.50 to -0.50 diopters). No abnormalities were found in brain imaging tests. Refractive errors were not correlated with NPA or NPC (rho = 0.148, p = 0.511; rho = 0.319, p = 0.339; respectively). The correlation between age and NPA was not significant (rho = -395, p = 0.069). However, the correlation between age and NPC was negative (rho = -0.508, p = 0.016). Three of 11 patients were lost to follow-up, and 6 of 8 patients had permanent insufficiency of accommodation. Accommodation insufficiency is most common in emmetropia, however, refractive errors and age are not correlated with accommodation insufficiency. Dysfunction of accommodation can be permanent in the isolated accommodation insufficiency.

A Powerful Approach to Estimating Annotation-Stratified Genetic Covariance via GWAS Summary Statistics.

Science.gov (United States)

Lu, Qiongshi; Li, Boyang; Ou, Derek; Erlendsdottir, Margret; Powles, Ryan L; Jiang, Tony; Hu, Yiming; Chang, David; Jin, Chentian; Dai, Wei; He, Qidu; Liu, Zefeng; Mukherjee, Shubhabrata; Crane, Paul K; Zhao, Hongyu

2017-12-07

Despite the success of large-scale genome-wide association studies (GWASs) on complex traits, our understanding of their genetic architecture is far from complete. Jointly modeling multiple traits' genetic profiles has provided insights into the shared genetic basis of many complex traits. However, large-scale inference sets a high bar for both statistical power and biological interpretability. Here we introduce a principled framework to estimate annotation-stratified genetic covariance between traits using GWAS summary statistics. Through theoretical and numerical analyses, we demonstrate that our method provides accurate covariance estimates, thereby enabling researchers to dissect both the shared and distinct genetic architecture across traits to better understand their etiologies. Among 50 complex traits with publicly accessible GWAS summary statistics (N total ≈ 4.5 million), we identified more than 170 pairs with statistically significant genetic covariance. In particular, we found strong genetic covariance between late-onset Alzheimer disease (LOAD) and amyotrophic lateral sclerosis (ALS), two major neurodegenerative diseases, in single-nucleotide polymorphisms (SNPs) with high minor allele frequencies and in SNPs located in the predicted functional genome. Joint analysis of LOAD, ALS, and other traits highlights LOAD's correlation with cognitive traits and hints at an autoimmune component for ALS. Copyright © 2017 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Subchondral insufficiency fractures of the femoral head

Energy Technology Data Exchange (ETDEWEB)

Davies, M.; Cassar-Pullicino, V.N. [Department of Radiology, Robert Jones and Agnes Hunt Orthopaedic and District Hospital, Oswestry, SY10 7AG, Shropshire (United Kingdom); Darby, A.J. [Department of Pathology, Robert Jones and Agnes Hunt Orthopaedic and District Hospital, Oswestry, SY10 7AG, Shropshire (United Kingdom)

2004-02-01

The aim of this study was to increase awareness of, and to show the variable clinical and radiological features of, subchondral insufficiency fractures of the femoral head. The clinical and radiological findings in 7 patients with subchondral insufficiency fractures of the femoral head were reviewed retrospectively. The diagnosis was confirmed histologically in 4 patients. Radiographs were performed in all patients, MRI in 5 and scintigraphy in 4 patients. Radiographs showed varying degrees of femoral head collapse in 4 patients. In the remaining 3 patients radiographs showed a normal femoral head, regional osteoporosis and focal sclerosis, respectively. Magnetic resonance imaging showed a low-signal band on T1- and T2-weighted images in the subchondral bone adjacent or parallel to the articular surface associated with bone marrow oedema. Scintigraphy showed increased uptake in the femoral head. Insufficiency fractures of the femoral head are easily overlooked or confused with avascular necrosis and, when there is significant joint destruction, osteoarthritis. Unsuspected insufficiency fracture of the femoral head can lead to significant and rapid loss of bone stock in osteoporotic patients waiting for arthroplasty for osteoarthritis. Increased awareness of this condition will hopefully lead to earlier diagnosis and a successful outcome of conservative treatment. (orig.)

Adrenal Insufficiency and Addison's Disease

Science.gov (United States)

... These conditions can lead to an adrenal crisis. Pregnancy Women with adrenal insufficiency who become pregnant are ... can benefit from following a diet rich in sodium. A health care provider or a dietitian can ...

Fuzzy Controller for a Voltage-Regulated Solar-Powered MPPT System for Hybrid Power System Applications

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Jaw-Kuen Shiau

2015-04-01

Full Text Available This paper presents the design of a fuzzy-logic-based voltage-regulated solar power maximum power point tracking (MPPT system for applications involving hybrid power systems. The system contains a solar power system and battery as the primary and secondary power sources, respectively. The solar system alone supplies power to the electric motor and maintains the output voltage at a predetermined level when it has sufficient power. When the solar power is insufficient, the solar system is operated at its maximum power point (MPP and the battery is engaged to compensate for the insufficiency. First, a variant of the incremental conductance MPP condition was established. Under the MPP condition, the voltage-regulated MPPT system was formulated as a feedback control system, where the MPP condition and voltage regulation requirements were used as the system inputs. Next, a fuzzy controller was developed to perform the voltage-regulated MPPT function for the hybrid power system. A simulation model based on Matrix laboratory (MATLAB/SIMULINK (a block diagram environment for multi-domain simulation and model-based design and a piecewise linear electric circuit simulation (PLECS tool for controlling the dc motor velocity was developed to verify the voltage-regulated solar power MPPT system.

Household food insufficiency is associated with dietary intake in Korean adults.

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Lee, Sang Eun; Song, Yoon Ju; Kim, Young; Choe, Jeongsook; Paik, Hee-Young

2016-04-01

To examine the association of food insufficiency with dietary intake and eating and health behaviours. A cross-sectional study. Data were obtained from a secondary source, the Fifth Korea National Health and Nutrition Examination Survey (2010-2012). The sample size consisted of 15 603 adults over 19 years of age (8898 households). Significant differences in socio-economic factors were observed according to food insufficiency level (Pfood-insufficient group, but we found no association with fat intake. Regarding micronutrients, Ca, Fe, vitamin A, thiamin, riboflavin niacin and vitamin C intakes were negatively associated with food insufficiency level (P trendfood groups, such as meat, fish, eggs and beans, vegetables and fruits, was significantly lower as food insufficiency level decreased after controlling for all possible variables; food group consumption also differed by sex. Overall eating and health behaviours were poorer in the mildly and severely food-insufficient groups, who received more food assistance but less nutritional education. Our results showed that dietary intake as well as eating and health behaviours are adversely associated with food insufficiency. These findings suggest that specific strategies to help food-insufficient individuals should be developed in order to improve their dietary quality and health status.

Primary ovarian insufficiency: an update

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Cox L

2014-02-01

Full Text Available Leticia Cox, James H LiuUH Case Medical Center, MacDonald Women's Hospital, Department of Obstetrics and Gynecology, Case Western Reserve University School of Medicine, Department of Reproductive Biology, Cleveland, OH, USAAbstract: Primary ovarian insufficiency is a condition that represents impaired ovarian function on a continuum with intermittent ovulation. This condition commonly leads to premature menopause, defined as cessation of ovulation prior to the age of 40 years. Because there are potential immediate and long-term consequences of hypoestrogenism, a timely diagnosis is invaluable. This comprehensive review will discuss identifiable causes for primary ovarian insufficiency, including genetic disorders and metabolic abnormalities, as well as review current strategies for diagnosis, evaluation, and management of women with this condition.Keywords: premature ovarian failure, premature menopause, ovarian dysfunction

[Adrenal insufficiency of the adult].

Science.gov (United States)

Jublanc, C; Bruckert, E

2016-12-01

Adrenal insufficiency is a rare but life-threatening disorder. Clinical manifestations include fatigue, weight loss, gastrointestinal manifestations and skin hyperpigmentation, the latter being specific of primary adrenal failure. Because of non-specific clinical features of this rare disorder, diagnosis can be delayed and adrenal failure be revealed by an acute crisis. Adrenal insufficiency can be primary (Addison disease), most frequently autoimmune, or secondary, resulting from long term administration of exogenous glucocorticoids or more rarely from pituitary disorders. Monitoring of substitutive treatment is now well codified. Patient education is very important in this chronic disease that remains associated with a persistent high risk of adrenal crisis. Copyright © 2016 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

Metallic stent placement in hemodialysis graft patients after insufficient balloon dilation

International Nuclear Information System (INIS)

Liang, Huei-Lung; Pan, Huay-Ben; Lin, Yih-Huie; Chen, Chiung-Yu; Lai, Pin-Hong; Yang, Chien-Fang; Chung, Hsiao-Min; Wu, Tung-Ho; Chou, Kang-Ju

2006-01-01

We wanted to report our experience of metallic stent placement after insufficient balloon dilation in graft hemodialysis patients. Twenty-three patients (13 loop grafts in the forearm and 10 straight grafts in the upper arm) underwent metallic stent placement due to insufficient flow after urokinase thrombolysis and balloon dilation. The indications for metallic stent deployment included 1) recoil and/or kinked venous stenosis in 21 patents (venous anastomosis: 17 patients, peripheral outflow vein: four patients); and 2) major vascular rupture in two patients. Metallic stents 8-10mm in diameter and 40-80 mm in length were used. Of them, eight stents were deployed across the elbow crease. Access patency was determined by clinical follow-up and the overall rates were calculated by Kaplan-Meier survival analysis. No procedure-related complications (stent fracture or central migration) were encountered except for a delayed Wallstent shortening/migration at the venous anastomosis, which resulted in early access failure. The overall primary and secondary patency rates (±standard error) of all the vascular accesses in our 23 patients at 3, 6, 12 and 24 months were 69%±9 and 88%±6,41% ±10 and 88%±6, 30%±10 and 77%±10, and 12%±8 and 61%±13, respectively. For the forearm and upper-arm grafts, the primary and secondary patency rates were 51%±16 and 86%±13 vs 45%±15 and 73%±13 at 6 months, and 25%±15 and 71%±17 vs 23%±17 and 73%±13 at 12 months (ρ = .436 and .224), respectively. Metallic stent placement is a safe and effective means for treating peripheral venous lesions in dialysis graft patients after insufficient balloon dilation. No statistically difference in the patency rates between the forearm and upper-arm patient groups was seen

Genetics Home Reference: fragile X-associated primary ovarian insufficiency

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... Share: Email Facebook Twitter Home Health Conditions FXPOI Fragile X-associated primary ovarian insufficiency Printable PDF Open All ... Javascript to view the expand/collapse boxes. Description Fragile X-associated primary ovarian insufficiency ( FXPOI ) is a condition ...

Nuclear power plants: 2009 atw compact statistics

International Nuclear Information System (INIS)

Anon.

2010-01-01

At the turn of 2009/2010, nuclear power plants were available for energy supply in 30 countries of the world. A total of 437 nuclear power plants, which is one plant less than at the 2008/2009 turn, were in operation with an aggregate gross power of approx. 391 GWe and an aggregate net power, respectively, of 371 GWe. The available gross power of nuclear power plants did not changed noticeably from 2008 to the end of 2009. In total 2 nuclear generating units were commissioned in 2009. One NPP started operation in India and one in Japan. Three nuclear generating units in Japan (2) und Lithuania (1) were decomissioned in 2009. 52 nuclear generating units, i.e. 10 plants more than at the end of 2008, with an aggregate gross power of approx. 51 GWe, were under construction in 14 countries end of 2009. New or continued projects are notified from (number of new projects): China (+9), Russia (1), and South Korea (1). Some 84 new nuclear power plants are in the concrete project design, planning and licensing phases worldwide; on some of them, contracts have already been awarded. Another units are in their preliminary project phases. (orig.)

Nuclear power plants: 2008 atw compact statistics

International Nuclear Information System (INIS)

Anon.

2009-01-01

At the turn of 2008/2009, nuclear power plants were available for energy supply in 31 countries of the world. A total of 438 nuclear power plants, which is one plant less than at the 2007/2008 turn, were in operation with an aggregate gross power of approx. 393 GWe and an aggregate net power, respectively, of 372 GWe. The available gross power of nuclear power plants didn't changed noticeabely from 2007 to the end of 2008. No nuclear generating unit was commissioned in 2008. One nuclear generating unit in the Slovak Republic was decomissioned in 2008. 42 nuclear generating units, i.e. 10 plants more than at the end of 2007, with an aggregate gross power of approx. 38 GWe, were under construction in 14 countries end of 2008. New or continued projects are notified from (in brackets: number of new projects): Bulgaria (2), China (5), South Korea (2), Russia (1), and the Slovak Republic (2). Some 80 new nuclear power plants are in the concrete project design, planning and licensing phases worldwide; on some of them, contracts have already been awarded. Another approximately 120 units are in their preliminary project phases. (orig.)

Recurrent tricuspid insufficiency: is the surgical repair technique a risk factor?

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Kara, Ibrahim; Koksal, Cengiz; Cakalagaoglu, Canturk; Sahin, Muslum; Yanartas, Mehmet; Ay, Yasin; Demir, Serdar

2013-01-01

This study compares the medium-term results of De Vega, modified De Vega, and ring annuloplasty techniques for the correction of tricuspid insufficiency and investigates the risk factors for recurrent grades 3 and 4 tricuspid insufficiency after repair. In our clinic, 93 patients with functional tricuspid insufficiency underwent surgical tricuspid repair from May 2007 through October 2010. The study was retrospective, and all the data pertaining to the patients were retrieved from hospital records. Functional capacity, recurrent tricuspid insufficiency, and risk factors aggravating the insufficiency were analyzed for each patient. In the medium term (25.4 ± 10.3 mo), the rates of grades 3 and 4 tricuspid insufficiency in the De Vega, modified De Vega, and ring annuloplasty groups were 31%, 23.1%, and 6.1%, respectively. Logistic regression analysis revealed that chronic obstructive pulmonary disease, left ventricular dysfunction (ejection fraction, tricuspid insufficiency. Medium-term survival was 90.6% for the De Vega group, 96.3% for the modified De Vega group, and 97.1% for the ring annuloplasty group. Ring annuloplasty provided the best relief from recurrent tricuspid insufficiency when compared with DeVega annuloplasty. Modified De Vega annuloplasty might be a suitable alternative to ring annuloplasty when rings are not available.

Pubic insufficiency fracture: MRI findings

International Nuclear Information System (INIS)

Min, Tae Kyu; Lee, Yeon Soo; Park, Jeong Mi; Kim, Jee Young; Chung, Hong Jun; Lee, Eun Hee; Lee, Eun Ja; Kang, So Won; Han Tae Il

2000-01-01

To evaluate the characteristic MRI findings of pubic insufficiency fracture. In nine cases of pubic insufficiency fracture, the findings of plain radiography (n=9), MRI (n=9), and bone scintigraphy (n=8) were reviewed. We retrospectively analyzed, with regard to fracture site, the destructive pattern revealed by plain radiography, and uptake by other pelvic bones, as demonstrated by RI bone scanning. The MR findings evaluated were the fracture gap and its signal intensity, the site and signal intensity of the soft tissue mass, and other pelvic bone fractures. Plain radiography revealed osteolysis and sclerosis of pubic bone in eight of nine cases (89%), and parasymphyseal fractures in seven (78%). RI indicated uptake by the sacrum in six cases (66%), and by the ilium in three (33%). MR findings of fracture gap (seven cases, 78%) were hypo to isointensity on T1WI, hyper intensity on T2WI and the absence of contrast enhancement. Soft tissue masses were found in seven cases (78%); in four of these the location was parasymphyseal, and in three, surrounding muscle was involved. Hypo to isointensity was revealed by T1WI, hyperintensity by T2WI, and there was peripheral enhancement. Other associated pelvic bone fractures involved the sacrum in seven cases and the ilium in four. The characteristic MR findings of pubic insufficiency fracture were parasymphyseal location, fracture gap, peripherally enhanced soft tissue mass formation, and fractures of other pelvic bones, namely the sacrum and ilium

Fuzzy statistical decision-making theory and applications

CERN Document Server

Kabak, Özgür

2016-01-01

This book offers a comprehensive reference guide to fuzzy statistics and fuzzy decision-making techniques. It provides readers with all the necessary tools for making statistical inference in the case of incomplete information or insufficient data, where classical statistics cannot be applied. The respective chapters, written by prominent researchers, explain a wealth of both basic and advanced concepts including: fuzzy probability distributions, fuzzy frequency distributions, fuzzy Bayesian inference, fuzzy mean, mode and median, fuzzy dispersion, fuzzy p-value, and many others. To foster a better understanding, all the chapters include relevant numerical examples or case studies. Taken together, they form an excellent reference guide for researchers, lecturers and postgraduate students pursuing research on fuzzy statistics. Moreover, by extending all the main aspects of classical statistical decision-making to its fuzzy counterpart, the book presents a dynamic snapshot of the field that is expected to stimu...

Increased hallux angle in children and its association with insufficient length of footwear: A community based cross-sectional study

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Kundi Michael

2009-12-01

Full Text Available Abstract Background Wearing shoes of insufficient length during childhood has often been cited as leading to deformities of the foot, particularly to the development of hallux valgus disorders. Until now, these assumptions have not been confirmed through scientific research. This study aims to investigate whether this association can be statistically proven, and if children who wear shoes of insufficient length actually do have a higher risk of a more pronounced lateral deviation of the hallux. Methods 858 pre-school children were included in the study. The study sample was stratified by sex, urban/rural areas and Austrian province. The hallux angle and the length of the feet were recorded. The inside length of the children's footwear (indoor shoes worn in pre-school and outdoor shoes were assessed. Personal data and different anthropometric measurements were taken. The risk of hallux valgus deviation was statistically tested by a stepwise logistic regression analysis and the relative risk (odds ratio for a hallux angle ≥ 4 degrees was calculated. Results Exact examinations of the hallux angle could be conducted on a total of 1,579 individual feet. Only 23.9% out of 1,579 feet presented a straight position of the great toe. The others were characterized by lateral deviations (valgus position at different degrees, equalling 10 degrees or greater in 14.2% of the children's feet. 88.8% of 808 children examined wore indoor footwear that was of insufficient length, and 69.4% of 812 children wore outdoor shoes that were too short. A significant relationship was observed between the lengthwise fit of the shoes and the hallux angle: the shorter the shoe, the higher the value of the hallux angle. The relative risk (odds ratio of a lateral hallux deviation of ≥ 4 degrees in children wearing shoes of insufficient length was significantly increased. Conclusions There is a significant relationship between the hallux angle in children and footwear that is

Increased hallux angle in children and its association with insufficient length of footwear: A community based cross-sectional study

Science.gov (United States)

2009-01-01

Background Wearing shoes of insufficient length during childhood has often been cited as leading to deformities of the foot, particularly to the development of hallux valgus disorders. Until now, these assumptions have not been confirmed through scientific research. This study aims to investigate whether this association can be statistically proven, and if children who wear shoes of insufficient length actually do have a higher risk of a more pronounced lateral deviation of the hallux. Methods 858 pre-school children were included in the study. The study sample was stratified by sex, urban/rural areas and Austrian province. The hallux angle and the length of the feet were recorded. The inside length of the children's footwear (indoor shoes worn in pre-school and outdoor shoes) were assessed. Personal data and different anthropometric measurements were taken. The risk of hallux valgus deviation was statistically tested by a stepwise logistic regression analysis and the relative risk (odds ratio) for a hallux angle ≥ 4 degrees was calculated. Results Exact examinations of the hallux angle could be conducted on a total of 1,579 individual feet. Only 23.9% out of 1,579 feet presented a straight position of the great toe. The others were characterized by lateral deviations (valgus position) at different degrees, equalling 10 degrees or greater in 14.2% of the children's feet. 88.8% of 808 children examined wore indoor footwear that was of insufficient length, and 69.4% of 812 children wore outdoor shoes that were too short. A significant relationship was observed between the lengthwise fit of the shoes and the hallux angle: the shorter the shoe, the higher the value of the hallux angle. The relative risk (odds ratio) of a lateral hallux deviation of ≥ 4 degrees in children wearing shoes of insufficient length was significantly increased. Conclusions There is a significant relationship between the hallux angle in children and footwear that is too short in length. The

[Association between Williams syndrome and adrenal insufficiency].

Science.gov (United States)

Rchachi, Meryem; Larwanou, Maazou Mahamane; El Ouahabi, Hanan; Ajdi, Farida

2017-01-01

Williams syndrome is a developmental disorder including dysmorphia, cardiovascular malformations and a specific neuropsychological profile together with other associated disorders. We report the case of a 17-year old girl, born of a non-inbred marriage, with Williams syndrome discovered during an assessment of degree of failure to thrive. Its association with primary adrenal insufficiency makes it unique. Diagnosis is confirmed by cytogenetic and molecular analysis. Its management consists of the implementation of treatment for adrenal insufficiency associated with a clinico-biological monitoring.

Nuclear power plants: 2004 atw compact statistics

International Nuclear Information System (INIS)

Anon.

2005-01-01

In late 2004, nuclear power plants were available for power supply or were under construction in 32 countries worldwide. A total of 441 nuclear power plants, i.e. two plants more than in late 2003, were in operation with an aggregate gross power of approx. 386 GWe and an aggregate net power, respectively, of 362 GWe, in 31 countries. The available capacity of nuclear power plants increased by approx. 5 GWe as a result of the additions by the six units newly commissioned: Hamaoka 5 (Japan), Ulchin 6 (Korea), Kalinin 3 (Russia), Khmelnitski 2 (Ukraine), Qinshan II-2 (People's Republic of China), and Rowno 4 (Ukraine). In addition, unit 3 of the Bruce A nuclear power plant in Canada with a power of 825 MWe was restarted after an outage of many years. Contrary to earlier plans, a recommissioning program was initiated for the Bruce A-1 and A-2 units, which are also down at present. Five plants were decommissioned for good in 2004; Chapelcross 1 to 4 with 50 MWe each in the United Kingdom, and Ignalina 1 with 1 300 MWe in Lithuania. 22 nuclear generating units with an aggregate gross power of 19 GWe in nine countries were under construction in late 2004. In India, construction work was started on a new project, the 500 MWe PFBR prototype fast breeder reactor. In France, the EDF utility announced its intention to build an EPR on the Flamanville site beginning in 2007. (orig.)

Nuclear power plants: 2005 atw compact statistics

International Nuclear Information System (INIS)

Anon.

2006-01-01

Nuclear power plants were available for power supply and under construction, respectively, in 32 countries of the world as per end of 2005. A total of 444 nuclear power plants, i.e. three plants more than at the end of 2004, with an aggregate gross power of approx. 389 GWe and an aggregate net power of 370 GWe, respectively, were in operation in 31 countries. The available capacity of nuclear power plants increased by some 4,5 GWe as a result of the capacities added by the four newly commissioned units of Higashidori 1 (Japan), Shika 2 (Japan), Tarapur 4 (India), and Tianwan 1 (China). In addition, unit A-1 of the Pickering nuclear power station in Canada, with 825 MWe, was restarted after a downtime of several years. Two plants were decommissioned for good in 2005: Obrigheim in Germany, and Barsebaeck 2 in Sweden. 23 nuclear generating units, i.e. one unit more than in late 2004, with an aggregate gross power of approx. 19 GWe were still under construction in nine countries by late 2005. In Pakistan, construction of a new project, Chasnupp 2, was started; in China, construction was begun of two units, Lingao Phase 2, units 3 and 4, and in Japan, the Shimane 3 generating unit is being built. (orig.)

Evaluation of the incidence on insufficient cytology results comparing different ultrasound-guided aspiration techniques for thyroid nodules

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Kim, Seong Hyng; Park, Jun Hyun; Park, Ji Kang [Dept. of Radiology, Jeju National University Hospital, Jeju National University School of Medicine, Jeju (Korea, Republic of)

2013-07-15

We compared the incidence of insufficient thyroid cytology due to blood-stained materials or low cellularity in terms of aspiration technique, especially focusing on the degree of suction pressure and needle size. Three experienced radiologists performed ultrasound-guided aspiration for thyroid nodules in 1174 thyroid nodules consecutively. Three different techniques were used; (A) using a 25 gauge needle with mainly capillary technique in 269 nodules; (B) using a 25 gauge needle with 3 cc syringe and minimal suction pressure in 303 nodules; (C) using a 22-23 gauge needle with 10 cc syringe and aspirator in 602 nodules. The differences of the incidence of the insufficient cytology among the three aspiration techniques and relationships of the incidence and needle size/degree of suction pressure was statistically analyzed using the Mann-Whitney U test and the chi-square test with linear-by-linear association. Overall, the difference in insufficient cytology was significant across the three aspiration technique (p = 0.004), and the incidence tended to increase significantly with increase of needle size and degree of suction pressure (p < 0.001). A pairwise comparison of aspiration techniques found significant differences (p = 0.003) between techniques (A) and (C), and no differences between technique (B) and (C) (p 0.07) and between techniques (A) and (B) (p = 0.10). The incidence of insufficient cytology was significantly low in the capillary technique, and it increased significantly with the increase of needle size and degree of suction pressure.

Evaluation of the incidence on insufficient cytology results comparing different ultrasound-guided aspiration techniques for thyroid nodules

International Nuclear Information System (INIS)

Kim, Seong Hyng; Park, Jun Hyun; Park, Ji Kang

2013-01-01

We compared the incidence of insufficient thyroid cytology due to blood-stained materials or low cellularity in terms of aspiration technique, especially focusing on the degree of suction pressure and needle size. Three experienced radiologists performed ultrasound-guided aspiration for thyroid nodules in 1174 thyroid nodules consecutively. Three different techniques were used; (A) using a 25 gauge needle with mainly capillary technique in 269 nodules; (B) using a 25 gauge needle with 3 cc syringe and minimal suction pressure in 303 nodules; (C) using a 22-23 gauge needle with 10 cc syringe and aspirator in 602 nodules. The differences of the incidence of the insufficient cytology among the three aspiration techniques and relationships of the incidence and needle size/degree of suction pressure was statistically analyzed using the Mann-Whitney U test and the chi-square test with linear-by-linear association. Overall, the difference in insufficient cytology was significant across the three aspiration technique (p = 0.004), and the incidence tended to increase significantly with increase of needle size and degree of suction pressure (p < 0.001). A pairwise comparison of aspiration techniques found significant differences (p = 0.003) between techniques (A) and (C), and no differences between technique (B) and (C) (p 0.07) and between techniques (A) and (B) (p = 0.10). The incidence of insufficient cytology was significantly low in the capillary technique, and it increased significantly with the increase of needle size and degree of suction pressure.

Statistical utility theory for comparison of nuclear versus fossil power plant alternatives

International Nuclear Information System (INIS)

Garribba, S.; Ovi, A.

1977-01-01

A statistical formulation of utility theory is developed for decision problems concerned with the choice among alternative strategies in electric energy production. Four alternatives are considered: nuclear power, fossil power, solar energy, and conservation policy. Attention is focused on a public electric utility thought of as a rational decision-maker. A framework for decisions is then suggested where the admissible strategies and their possible consequences represent the information available to the decision-maker. Once the objectives of the decision process are assessed, consequences can be quantified in terms of measures of effectiveness. Maximum expected utility is the criterion of choice among alternatives. Steps toward expected values are the evaluation of the multidimensional utility function and the assessment of subjective probabilities for consequences. In this respect, the multiplicative form of the utility function seems less restrictive than the additive form and almost as manageable to implement. Probabilities are expressed through subjective marginal probability density functions given at a discrete number of points. The final stage of the decision model is to establish the value of each strategy. To this scope, expected utilities are computed and scaled. The result is that nuclear power offers the best alternative. 8 figures, 9 tables, 32 references

Osteoporotic compression fracture of the thoracolumbar spine and sacral insufficiency fracture: incidence and analysis of the relationship according to the clinical factors

International Nuclear Information System (INIS)

Kong, Jeong Hwa; Park, Ji Sun; Ryu, Kyung Nam

2006-01-01

To evaluate the incidence of sacral insufficiency fracture in osteoporotic patient with compression fracture of the thoracolumbar (T-L) spine on magnetic resonance image (MRI), and to analyze the correlation of variable clinical factors and the incidence of sacral insufficiency fracture. We retrospectively reviewed 160 patients (27 men, 133 women; age range of 50 to 89 years) who underwent spinal MRI and had compression fracture of the T-L spine. Compression fractures due to trauma or tumor were excluded. We evaluated the incidence of sacral insufficiency fracture according to the patients' age, sex, number of compression fractures, and the existence of bone marrow edema pattern of compression fracture. During the same period, we evaluated the incidence of spinal compression fracture in the patients of pelvic insufficiency fracture. Out of the 160 patients who had compression fracture in the T-L spine, 17 (10.6%) had insufficiency fracture of the sacrum. Compression fracture occurred almost 5 times more frequently in women (27:133), but the incidence of sacral insufficiency fracture was 2/27 for men (7.4%) and 15/133 for women (11.3%), with no statistically significant difference (ρ = 0.80). According to age, the ratio of insufficiency fracture to compression fracture was 0% (0/23) in the 50's, 10.6% (7/66) in the 60's, 12.5% (7/56) in the 70's, and 20.0% (3/15) in the 80's. In respect of single and multiple compression fracture, the incidence of sacral insufficiency fracture was 8/65 for men (12.3%) and 9/95 for women (9.5%), showing no significant difference (ρ = 0.37). In the patients with and without compression fracture with bone marrow edema, insufficiency fracture occurred in 5/76 (6.6%) and 12/84 (14.3%), respectively. On the other hand, of the 67 patients who had pelvic insufficiency fracture, 27 (40.3%) also had spinal compression fracture. About 10% of the patients with osteoporotic compression fracture in the T/L spine also had pelvic sacral

Magnetic resonance imaging in osteomalacic insufficiency fractures of the pelvis

Energy Technology Data Exchange (ETDEWEB)

Kanberoglu, K. [Department of Radiology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey)]. E-mail: zkanber@istanbul.edu.tr; Kantarci, F. [Department of Radiology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey); Cebi, D. [Department of Radiology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey); Yilmaz, M.H. [Department of Radiology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey); Kurugoglu, S. [Department of Radiology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey); Bilici, A. [Department of Internal Medicine, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey); Koyuncu, H. [Department of Physical Medicine and Rehabilitation, Cerrahpasa Medical Faculty, Istanbul University, Istanbul (Turkey)

2005-01-01

AIMS: To report the magnetic resonance imaging (MRI) findings of osteomalacic insufficiency fractures of the pelvis. MATERIALS AND METHODS: In all, 12 persons presenting with chronic pelvic pain and with a definitive diagnosis of osteomalacia (OM) were enrolled in this study. Radiological work-up included direct radiographs (n=12), computed tomography (n=5), scintigraphy n=12) and MRI (n=12). The location of the insufficiency fractures and corresponding MRI appearances were evaluated. Depending on the presence or absence of signal intensity around the fractures, the lesions were grouped into active and chronic forms. RESULTS: A total of 34 insufficiency fractures were depicted on imaging studies. MRI demonstrated 33 of the lesions. All the insufficiency fractures were seen as a hypointense lines or fissures on T1- and T2-weighted and STIR MR images. There was a high frequency of insufficiency fractures at the sacrum and iliac bone (16/34, 47%). Overall, 11 chronic-type (no abnormal signal intensity around the fissure) and 22 active-type (abnormal signal intensity around the fissure) insufficiency fractures were detected by MRI. Follow-up MR examinations of 2 subjects showed that abnormal signal intensity had disappeared after appropriate treatment. CONCLUSION: The results of this study showed that the iliac and sacral bones are frequently involved in patients with OM. MRI can determine the clinical activity of the disease, and can monitor the response to treatment of the active type of insufficiency fractures.

Magnetic resonance imaging in osteomalacic insufficiency fractures of the pelvis

International Nuclear Information System (INIS)

Kanberoglu, K.; Kantarci, F.; Cebi, D.; Yilmaz, M.H.; Kurugoglu, S.; Bilici, A.; Koyuncu, H.

2005-01-01

AIMS: To report the magnetic resonance imaging (MRI) findings of osteomalacic insufficiency fractures of the pelvis. MATERIALS AND METHODS: In all, 12 persons presenting with chronic pelvic pain and with a definitive diagnosis of osteomalacia (OM) were enrolled in this study. Radiological work-up included direct radiographs (n=12), computed tomography (n=5), scintigraphy n=12) and MRI (n=12). The location of the insufficiency fractures and corresponding MRI appearances were evaluated. Depending on the presence or absence of signal intensity around the fractures, the lesions were grouped into active and chronic forms. RESULTS: A total of 34 insufficiency fractures were depicted on imaging studies. MRI demonstrated 33 of the lesions. All the insufficiency fractures were seen as a hypointense lines or fissures on T1- and T2-weighted and STIR MR images. There was a high frequency of insufficiency fractures at the sacrum and iliac bone (16/34, 47%). Overall, 11 chronic-type (no abnormal signal intensity around the fissure) and 22 active-type (abnormal signal intensity around the fissure) insufficiency fractures were detected by MRI. Follow-up MR examinations of 2 subjects showed that abnormal signal intensity had disappeared after appropriate treatment. CONCLUSION: The results of this study showed that the iliac and sacral bones are frequently involved in patients with OM. MRI can determine the clinical activity of the disease, and can monitor the response to treatment of the active type of insufficiency fractures

The efficiency of retrospective artifact correction methods in improving the statistical power of between-group differences in spinal cord DTI.

Science.gov (United States)

David, Gergely; Freund, Patrick; Mohammadi, Siawoosh

2017-09-01

Diffusion tensor imaging (DTI) is a promising approach for investigating the white matter microstructure of the spinal cord. However, it suffers from severe susceptibility, physiological, and instrumental artifacts present in the cord. Retrospective correction techniques are popular approaches to reduce these artifacts, because they are widely applicable and do not increase scan time. In this paper, we present a novel outlier rejection approach (reliability masking) which is designed to supplement existing correction approaches by excluding irreversibly corrupted and thus unreliable data points from the DTI index maps. Then, we investigate how chains of retrospective correction techniques including (i) registration, (ii) registration and robust fitting, and (iii) registration, robust fitting, and reliability masking affect the statistical power of a previously reported finding of lower fractional anisotropy values in the posterior column and lateral corticospinal tracts in cervical spondylotic myelopathy (CSM) patients. While established post-processing steps had small effect on the statistical power of the clinical finding (slice-wise registration: -0.5%, robust fitting: +0.6%), adding reliability masking to the post-processing chain increased it by 4.7%. Interestingly, reliability masking and registration affected the t-score metric differently: while the gain in statistical power due to reliability masking was mainly driven by decreased variability in both groups, registration slightly increased variability. In conclusion, reliability masking is particularly attractive for neuroscience and clinical research studies, as it increases statistical power by reducing group variability and thus provides a cost-efficient alternative to increasing the group size. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Nuclear power plants: 2013 atw compact statistics

Energy Technology Data Exchange (ETDEWEB)

Anon.

2014-03-15

At the end of 2013, nuclear power plants were available for energy supply in 31 countries of the world. A total of 437 nuclear power plants were in operation with an aggregate gross power of approx. 393 GWe and an aggregate net power, respectively, of 372 GWe. This means that the number was unchanged compared to the previous year's number on 31 December 2012. The available gross power of nuclear power plants increased by approx. 2 GWe from 2012 to the end of 2013. In total 4 nuclear generating units were commissioned in 2013 in China (+2) and in the Republic Korea (+1). 6 nuclear generating units were decommissioned in 2013. Four units in the U.S.A. (-4) were shut down due to economical reasons. In Canada (-2) the operation status of 2 units was changed from long-term shutdown to permanently shutdown. 70 nuclear generating units with an aggregate gross power of approx. 73 GWe, were under construction in 15 countries end of 2013. New or continued projects are notified from (in brackets: number of new projects) China (+3), Belarus (+1), Rep. of Korea (+1) and the United Arab Emirates (+1). Some 115 new nuclear power plants are in the concrete project design, planning and licensing phases worldwide; on some of them, contracts have already been awarded. Another units are in their preliminary project phases. (orig.)

Nuclear power plants: 2013 atw compact statistics

International Nuclear Information System (INIS)

Anon.

2014-01-01

At the end of 2013, nuclear power plants were available for energy supply in 31 countries of the world. A total of 437 nuclear power plants were in operation with an aggregate gross power of approx. 393 GWe and an aggregate net power, respectively, of 372 GWe. This means that the number was unchanged compared to the previous year's number on 31 December 2012. The available gross power of nuclear power plants increased by approx. 2 GWe from 2012 to the end of 2013. In total 4 nuclear generating units were commissioned in 2013 in China (+2) and in the Republic Korea (+1). 6 nuclear generating units were decommissioned in 2013. Four units in the U.S.A. (-4) were shut down due to economical reasons. In Canada (-2) the operation status of 2 units was changed from long-term shutdown to permanently shutdown. 70 nuclear generating units with an aggregate gross power of approx. 73 GWe, were under construction in 15 countries end of 2013. New or continued projects are notified from (in brackets: number of new projects) China (+3), Belarus (+1), Rep. of Korea (+1) and the United Arab Emirates (+1). Some 115 new nuclear power plants are in the concrete project design, planning and licensing phases worldwide; on some of them, contracts have already been awarded. Another units are in their preliminary project phases. (orig.)

The power and statistical behaviour of allele-sharing statistics when ...

Indian Academy of Sciences (India)

Unknown

3Human Genetics Division, School of Medicine, University of Southampton, Southampton SO16 6YD, UK. Abstract ... that the statistic S-#alleles gives good performance for recessive ... (H50) of the families are linked to the single marker. The.

Predictive factors for exocrine pancreatic insufficiency after pancreatoduodenectomy with pancreaticogastrostomy.

Science.gov (United States)

Nakamura, Hiroyuki; Murakami, Yoshiaki; Uemura, Kenichiro; Hayashidani, Yasuo; Sudo, Takeshi; Ohge, Hiroki; Sueda, Taijiro

2009-07-01

The aim of this study was to determine risk factors for exocrine pancreatic insufficiency after pancreatoduodenectomy (PD) with pancreaticogastrostomy (PG). A (13)C-labeled mixed triglyceride breath test was performed in 61 patients after PD to assess exocrine pancreatic function. Percent (13)CO(2) cumulative dose at 7 h pancreatic insufficiency. Abdominal computed tomography scans were utilized to assess the dilatation of the main pancreatic duct (MPD dilatation) in the remnant. Thirty-eight of 61 patients (62.3%) were diagnosed with exocrine pancreatic insufficiency. Univariate analysis identified significant associations between two preoperative factors (preoperative impaired endocrine function and a hard pancreatic texture induced by preexisting obstructive pancreatitis), plus one postoperative factor (MPD dilatation caused by PG stricture) and exocrine pancreatic insufficiency (P pancreatic insufficiency after PD may be partly explainable by preexisting obstructive pancreatitis prior to surgery, surgeons desiring to obtain better postoperative exocrine pancreatic function after PD would be well-advised to devote considerable attention to preventing PG stricture.

Statistical analysis of wind power in the region of Veracruz (Mexico)

Energy Technology Data Exchange (ETDEWEB)

Cancino-Solorzano, Yoreley [Departamento de Ing Electrica-Electronica, Instituto Tecnologico de Veracruz, Calzada Miguel A. de Quevedo 2779, 91860 Veracruz (Mexico); Xiberta-Bernat, Jorge [Departamento de Energia, Escuela Tecnica Superior de Ingenieros de Minas, Universidad de Oviedo, C/Independencia, 13, 2a Planta, 33004 Oviedo (Spain)

2009-06-15

The capacity of the Mexican electricity sector faces the challenge of satisfying the demand of the 80 GW forecast by 2016. This value supposes a steady yearly average increase of some 4.9%. The electricity sector increases for the next eight years will be mainly made up of combined cycle power plants which could be a threat to the energy supply of the country due to the fact that the country is not self-sufficient in natural gas. As an alternative wind energy resource could be a more suitable option compared with combined cycle power plants. This option is backed by market trends indicating that wind technology costs will continue to decrease in the near future as has happened in recent years. Evaluation of the eolic potential in different areas of the country must be carried out in order to achieve the best use possible of this option. This paper gives a statistical analysis of the wind characteristics in the region of Veracruz. The daily, monthly and annual wind speed values have been studied together with their prevailing direction. The data analyzed correspond to five meteorological stations and two anemometric stations located in the aforementioned area. (author)

Statistical analysis of wind power in the region of Veracruz (Mexico)

International Nuclear Information System (INIS)

Cancino-Solorzano, Yoreley; Xiberta-Bernat, Jorge

2009-01-01

The capacity of the Mexican electricity sector faces the challenge of satisfying the demand of the 80 GW forecast by 2016. This value supposes a steady yearly average increase of some 4.9%. The electricity sector increases for the next eight years will be mainly made up of combined cycle power plants which could be a threat to the energy supply of the country due to the fact that the country is not self-sufficient in natural gas. As an alternative wind energy resource could be a more suitable option compared with combined cycle power plants. This option is backed by market trends indicating that wind technology costs will continue to decrease in the near future as has happened in recent years. Evaluation of the eolic potential in different areas of the country must be carried out in order to achieve the best use possible of this option. This paper gives a statistical analysis of the wind characteristics in the region of Veracruz. The daily, monthly and annual wind speed values have been studied together with their prevailing direction. The data analyzed correspond to five meteorological stations and two anemometric stations located in the aforementioned area. (author)

Distance matters. Assessing socioeconomic impacts of the Dukovany nuclear power plant in the Czech Republic: Local perceptions and statistical evidence

Directory of Open Access Journals (Sweden)

Frantál Bohumil

2016-03-01

Full Text Available The effect of geographical distance on the extent of socioeconomic impacts of the Dukovany nuclear power plant in the Czech Republic is assessed by combining two different research approaches. First, we survey how people living in municipalities in the vicinity of the power plant perceive impacts on their personal quality of life. Second, we explore the effects of the power plant on regional development by analysing long-term statistical data about the unemployment rate, the share of workers in the energy sector and overall job opportunities in the respective municipalities. The results indicate that the power plant has had significant positive impacts on surrounding communities both as perceived by residents and as evidenced by the statistical data. The level of impacts is, however, significantly influenced by the spatial and social distances of communities and individuals from the power plant. The perception of positive impacts correlates with geographical proximity to the power plant, while the hypothetical distance where positive effects on the quality of life are no longer perceived was estimated at about 15 km. Positive effects are also more likely to be reported by highly educated, young and middle-aged and economically active persons, whose work is connected to the power plant.

Pancreatic insufficiency after different resections for benign tumours.

Science.gov (United States)

Falconi, M; Mantovani, W; Crippa, S; Mascetta, G; Salvia, R; Pederzoli, P

2008-01-01

Pancreatic resections for benign diseases may lead to long-term endocrine/exocrine impairment. The aim of this study was to compare postoperative and long-term results after different pancreatic resections for benign disease. Between 1990 and 1999, 62 patients underwent pancreaticoduodenectomy (PD), 36 atypical resection (AR) and 64 left pancreatectomy (LP) for benign tumours. Exocrine and endocrine pancreatic function was evaluated by 72-h faecal chymotrypsin and oral glucose tolerance test. The incidence of pancreatic fistula was significantly higher after AR than after LP (11 of 36 versus seven of 64; P = 0.028). The long-term incidence of endocrine pancreatic insufficiency was significantly lower after AR than after PD (P insufficiency was more common after PD (P endocrine and exocrine insufficiency was higher for PD and LP than for AR (32, 27 and 3 per cent respectively at 1 year; 58, 29 and 3 per cent at 5 years; P pancreatic resections are associated with different risks of developing long-term pancreatic insufficiency. AR represents the best option in terms of long-term endocrine and exocrine function, although it is associated with more postoperative complications. Copyright (c) 2007 British Journal of Surgery Society Ltd.

Statistical power in parallel group point exposure studies with time-to-event outcomes: an empirical comparison of the performance of randomized controlled trials and the inverse probability of treatment weighting (IPTW) approach.

Science.gov (United States)

Austin, Peter C; Schuster, Tibor; Platt, Robert W

2015-10-15

Estimating statistical power is an important component of the design of both randomized controlled trials (RCTs) and observational studies. Methods for estimating statistical power in RCTs have been well described and can be implemented simply. In observational studies, statistical methods must be used to remove the effects of confounding that can occur due to non-random treatment assignment. Inverse probability of treatment weighting (IPTW) using the propensity score is an attractive method for estimating the effects of treatment using observational data. However, sample size and power calculations have not been adequately described for these methods. We used an extensive series of Monte Carlo simulations to compare the statistical power of an IPTW analysis of an observational study with time-to-event outcomes with that of an analysis of a similarly-structured RCT. We examined the impact of four factors on the statistical power function: number of observed events, prevalence of treatment, the marginal hazard ratio, and the strength of the treatment-selection process. We found that, on average, an IPTW analysis had lower statistical power compared to an analysis of a similarly-structured RCT. The difference in statistical power increased as the magnitude of the treatment-selection model increased. The statistical power of an IPTW analysis tended to be lower than the statistical power of a similarly-structured RCT.

Powering Africa: Meeting the financing and reform challenges

International Nuclear Information System (INIS)

Eberhard, Anton; Shkaratan, Maria

2012-01-01

Sub-Saharan Africa faces chronic power problems, including insufficient generation capacity, low connectivity, poor reliability, and high costs, all of which constrain development. The investment requirements to meet Africa's power needs are noted and strategies to address the funding gap are set out. The time for an ideological debate on public versus private investment is over—both are needed. Africa's key challenges are the management of hybrid power markets, the reform of state-owned utilities, cost-reflective pricing, better targeting of subsidies, the nimbler rollout of electrification, and stronger regional integration. - Highlights: ► Africa has insufficient power generation, low connectivity, poor reliability, and high costs. ► Investment requirements to meet Africa's power needs are calculated. ► Key challenges are the management of hybrid power markets and the reform of state-owned utilities. ► Other challenges are cost-reflective pricing, extending access, and stronger regional integration.

Renal tubular acidosis complicated with hyponatremia due to cortisol insufficiency

OpenAIRE

Izumi, Yuichiro; Nakayama, Yushi; Onoue, Tomoaki; Inoue, Hideki; Mukoyama, Masashi

2015-01-01

Adrenocortical insufficiency such as occurs in Addison's disease causes hyponatremia and renal tubular acidosis (RTA). Hyponatremia results from both aldosterone and cortisol insufficiency. RTA is due to aldosterone insufficiency. The involvement of cortisol in RTA is unclear. Here, we report a woman in her 70s who was admitted to our hospital with severe hyponatremia (106 mEq/l) and RTA. The patient exhibited low plasma cortisol levels with little response to rapid adrenocorticotropic hormon...

Statistical Diagnosis of the Best Weibull Methods for Wind Power Assessment for Agricultural Applications

Directory of Open Access Journals (Sweden)

Abul Kalam Azad

2014-05-01

Full Text Available The best Weibull distribution methods for the assessment of wind energy potential at different altitudes in desired locations are statistically diagnosed in this study. Seven different methods, namely graphical method (GM, method of moments (MOM, standard deviation method (STDM, maximum likelihood method (MLM, power density method (PDM, modified maximum likelihood method (MMLM and equivalent energy method (EEM were used to estimate the Weibull parameters and six statistical tools, namely relative percentage of error, root mean square error (RMSE, mean percentage of error, mean absolute percentage of error, chi-square error and analysis of variance were used to precisely rank the methods. The statistical fittings of the measured and calculated wind speed data are assessed for justifying the performance of the methods. The capacity factor and total energy generated by a small model wind turbine is calculated by numerical integration using Trapezoidal sums and Simpson’s rules. The results show that MOM and MLM are the most efficient methods for determining the value of k and c to fit Weibull distribution curves.

Adrenal Insufficiency Caused by Locally Applied Glucocorticoids-Myth or Fact?

DEFF Research Database (Denmark)

Dinsen, Stina; Klose, Marianne; Rasmussen, Åse Krogh

2015-01-01

Case-reports have made it evident that both inhaled, percutaneous, intranasal, intraarticular and ophthalmic administered glucocorticoids have the potential to cause life threatening adrenal insufficiency. With few and sometimes conflicting data and study methodology the prevalence of adrenal...... insufficiency secondary to locally applied glucocorticoids is not clear. Adrenal insufficiency can only be correctly evaluated by a stimulation test, and has by this procedure been reported in up to 40-50% of patients treated with high-dose inhaled glucocorticoids. Medium- to low-dose inhaled glucocorticoids...... have been shown to cause adrenal suppression in 0-16% of patients. Glucocorticoid creams and nasal glucocorticoids can cause adrenal insufficiency, also when used within prescribed doses, but the frequency seems to be less than with inhaled glucocorticoids. Intraarticularly administered glucocorticoids...

Pancreatic insufficiency secondary to abdominal radiotherapy

International Nuclear Information System (INIS)

Dookeran, K.A.; Thompson, M.M.; Allum, W.H.

1993-01-01

Delayed post-irradiation steatorrhoea secondary to acute pancreatic insufficiency is rare. The authors describe a case occurring in a patient 23 years following radical abdominal radiotherapy for testicular seminoma. (Author)

Pancreatic insufficiency secondary to abdominal radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Dookeran, K.A.; Thompson, M.M.; Allum, W.H. (Leicester Royal Infirmary (United Kingdom). Dept. of Surgery)

1993-02-01

Delayed post-irradiation steatorrhoea secondary to acute pancreatic insufficiency is rare. The authors describe a case occurring in a patient 23 years following radical abdominal radiotherapy for testicular seminoma. (Author).

An investigation of the statistical power of neutrality tests based on comparative and population genetic data

DEFF Research Database (Denmark)

Zhai, Weiwei; Nielsen, Rasmus; Slatkin, Montgomery

2009-01-01

In this report, we investigate the statistical power of several tests of selective neutrality based on patterns of genetic diversity within and between species. The goal is to compare tests based solely on population genetic data with tests using comparative data or a combination of comparative...... and population genetic data. We show that in the presence of repeated selective sweeps on relatively neutral background, tests based on the d(N)/d(S) ratios in comparative data almost always have more power to detect selection than tests based on population genetic data, even if the overall level of divergence...... selection. The Hudson-Kreitman-Aguadé test is the most powerful test for detecting positive selection among the population genetic tests investigated, whereas McDonald-Kreitman test typically has more power to detect negative selection. We discuss our findings in the light of the discordant results obtained...

Statistical analysis of the variation of floor vibrations in nuclear power plants subject to seismic loads

International Nuclear Information System (INIS)

Jussila, Vilho; Li, Yue; Fülöp, Ludovic

2016-01-01

Highlights: • Floor flexibility plays a non-negligible role in amplifying horizontal vibrations. • COV of in-floor horizontal and vertical acceleration are 0.15–0.25 and 0.25–0.55. • In-floor variation of vibrations is higher in lower floors. • Floor spectra from limited nodes underestimates vibrations by a factor of 1.5–1.75. - Abstract: Floor vibration of a reactor building subjected to seismic loads was investigated, with the aim of quantifying the variability of vibrations on each floor. A detailed 3D building model founded on the bedrock was excited simultaneously in three directions by artificial accelerograms compatible with Finnish ground response spectra. Dynamic simulation for 21 s was carried out using explicit time integration. The extracted results of the simulation were acceleration in several floor locations, transformed to pseudo-acceleration (PSA) spectra in the next stage. At first, the monitored locations on the floors were estimated by engineering judgement in order to arrive at a feasible number of floor nodes for post processing of the data. It became apparent that engineering judgment was insufficient to depict the key locations with high floor vibrations, which resulted in un-conservative vibration estimates. For this reason, a more systematic approach was later considered, in which nodes of the floors were selected with a more refined grid of 2 m. With this method, in addition to the highest PSA peaks in all directions, the full vibration distribution in each floor can be determined. A statistical evaluation of the floor responses was also carried out in order to define floor accelerations and PSAs with high confidence of non-exceedance. The conclusion was that in-floor variability can be as high as 50–60% and models with sufficiently dense node grids should be used in order to achieve a realistic estimate of floor vibration under seismic action. The effects of the shape of the input spectra, damping, and flexibility of the

Statistical analysis of the variation of floor vibrations in nuclear power plants subject to seismic loads

Energy Technology Data Exchange (ETDEWEB)

Jussila, Vilho [VTT Technical Research Centre of Finland Ltd, Kemistintie 3, 02230 Espoo (Finland); Li, Yue [Dept. of Civil Engineering, Case Western Reserve University, Cleveland, OH 44106 (United States); Fülöp, Ludovic, E-mail: ludovic.fulop@vtt.fi [VTT Technical Research Centre of Finland Ltd, Kemistintie 3, 02230 Espoo (Finland)

2016-12-01

Highlights: • Floor flexibility plays a non-negligible role in amplifying horizontal vibrations. • COV of in-floor horizontal and vertical acceleration are 0.15–0.25 and 0.25–0.55. • In-floor variation of vibrations is higher in lower floors. • Floor spectra from limited nodes underestimates vibrations by a factor of 1.5–1.75. - Abstract: Floor vibration of a reactor building subjected to seismic loads was investigated, with the aim of quantifying the variability of vibrations on each floor. A detailed 3D building model founded on the bedrock was excited simultaneously in three directions by artificial accelerograms compatible with Finnish ground response spectra. Dynamic simulation for 21 s was carried out using explicit time integration. The extracted results of the simulation were acceleration in several floor locations, transformed to pseudo-acceleration (PSA) spectra in the next stage. At first, the monitored locations on the floors were estimated by engineering judgement in order to arrive at a feasible number of floor nodes for post processing of the data. It became apparent that engineering judgment was insufficient to depict the key locations with high floor vibrations, which resulted in un-conservative vibration estimates. For this reason, a more systematic approach was later considered, in which nodes of the floors were selected with a more refined grid of 2 m. With this method, in addition to the highest PSA peaks in all directions, the full vibration distribution in each floor can be determined. A statistical evaluation of the floor responses was also carried out in order to define floor accelerations and PSAs with high confidence of non-exceedance. The conclusion was that in-floor variability can be as high as 50–60% and models with sufficiently dense node grids should be used in order to achieve a realistic estimate of floor vibration under seismic action. The effects of the shape of the input spectra, damping, and flexibility of the

How the Mastery Rubric for Statistical Literacy Can Generate Actionable Evidence about Statistical and Quantitative Learning Outcomes

Directory of Open Access Journals (Sweden)

Rochelle E. Tractenberg

2016-12-01

Full Text Available Statistical literacy is essential to an informed citizenry; and two emerging trends highlight a growing need for training that achieves this literacy. The first trend is towards “big” data: while automated analyses can exploit massive amounts of data, the interpretation—and possibly more importantly, the replication—of results are challenging without adequate statistical literacy. The second trend is that science and scientific publishing are struggling with insufficient/inappropriate statistical reasoning in writing, reviewing, and editing. This paper describes a model for statistical literacy (SL and its development that can support modern scientific practice. An established curriculum development and evaluation tool—the Mastery Rubric—is integrated with a new, developmental, model of statistical literacy that reflects the complexity of reasoning and habits of mind that scientists need to cultivate in order to recognize, choose, and interpret statistical methods. This developmental model provides actionable evidence, and explicit opportunities for consequential assessment that serves students, instructors, developers/reviewers/accreditors of a curriculum, and institutions. By supporting the enrichment, rather than increasing the amount, of statistical training in the basic and life sciences, this approach supports curriculum development, evaluation, and delivery to promote statistical literacy for students and a collective quantitative proficiency more broadly.

Whole Exome Sequencing for the differential diagnosis of primary adrenal insufficiency in children

Directory of Open Access Journals (Sweden)

Li F Chan

2015-08-01

Full Text Available Adrenal insufficiency is a rare, but potentially fatal medical condition. In children the cause is most commonly congenital and in recent years a growing number of causative gene mutations have been identified resulting in a myriad of syndromes that share adrenal insufficiency as one of the main characteristics. The evolution of adrenal insufficiency is dependent on the variant and the particular gene affected, meaning rapid and accurate diagnosis is imperative for effective treatment of the patient. Common practice is for candidate genes to be sequenced individually, which is a time consuming process and complicated by overlapping clinical phenotypes. However, with the availability, and increasing cost effectiveness of whole exome sequencing there is the potential for this to become a powerful diagnostic tool. Here we report the results of whole exome sequencing of 43 patients referred to us with a diagnosis of familial glucocorticoid deficiency (FGD who were mutation negative for MC2R, MRAP and STAR the most commonly mutated genes in FGD. WES provided a rapid genetic diagnosis in 17/43 sequenced patients, for the remaining 60% the gene defect may be within intronic/regulatory regions not covered by WES or may be in gene(s representing novel aetiologies. The diagnosis of isolated or familial glucocorticoid deficiency was only confirmed in 3 of the 17 patients, other genetic diagnoses were adrenal hypo- and hyperplasia, Triple A and autoimmune polyendocrinopathy syndrome type I, emphasizing both the difficulty of phenotypically distinguishing between disorders of PAI and the utility of WES as a tool to achieve this.

The thresholds for statistical and clinical significance

DEFF Research Database (Denmark)

Jakobsen, Janus Christian; Gluud, Christian; Winkel, Per

2014-01-01

BACKGROUND: Thresholds for statistical significance are insufficiently demonstrated by 95% confidence intervals or P-values when assessing results from randomised clinical trials. First, a P-value only shows the probability of getting a result assuming that the null hypothesis is true and does...... not reflect the probability of getting a result assuming an alternative hypothesis to the null hypothesis is true. Second, a confidence interval or a P-value showing significance may be caused by multiplicity. Third, statistical significance does not necessarily result in clinical significance. Therefore...... of the probability that a given trial result is compatible with a 'null' effect (corresponding to the P-value) divided by the probability that the trial result is compatible with the intervention effect hypothesised in the sample size calculation; (3) adjust the confidence intervals and the statistical significance...

Antineoplastic treatment of patients with renal insufficiency

International Nuclear Information System (INIS)

Rajec, J.; Mego, M.; Rajec, J.

2011-01-01

Kidneys are the main route of elimination for many antineoplastic drugs and their metabolites. The kidney dysfunction may lead to the drug cumulation in organism with the resulting increased systemic toxicity. A lot of used cytostatics requires a dose modification at different levels of renal insufficiency. Due to the lack of data from clinical trials, the limiting of systemic toxicity is difficult especially in patients with severe renal impairment or patients undergoing chronic hemodialysis. The following article is focused on the preventive strategies dealing with recommended dosing modification of various antineoplastic agents in patients with renal insufficiency. (author)

A powerful score-based test statistic for detecting gene-gene co-association.

Science.gov (United States)

Xu, Jing; Yuan, Zhongshang; Ji, Jiadong; Zhang, Xiaoshuai; Li, Hongkai; Wu, Xuesen; Xue, Fuzhong; Liu, Yanxun

2016-01-29

The genetic variants identified by Genome-wide association study (GWAS) can only account for a small proportion of the total heritability for complex disease. The existence of gene-gene joint effects which contains the main effects and their co-association is one of the possible explanations for the "missing heritability" problems. Gene-gene co-association refers to the extent to which the joint effects of two genes differ from the main effects, not only due to the traditional interaction under nearly independent condition but the correlation between genes. Generally, genes tend to work collaboratively within specific pathway or network contributing to the disease and the specific disease-associated locus will often be highly correlated (e.g. single nucleotide polymorphisms (SNPs) in linkage disequilibrium). Therefore, we proposed a novel score-based statistic (SBS) as a gene-based method for detecting gene-gene co-association. Various simulations illustrate that, under different sample sizes, marginal effects of causal SNPs and co-association levels, the proposed SBS has the better performance than other existed methods including single SNP-based and principle component analysis (PCA)-based logistic regression model, the statistics based on canonical correlations (CCU), kernel canonical correlation analysis (KCCU), partial least squares path modeling (PLSPM) and delta-square (δ (2)) statistic. The real data analysis of rheumatoid arthritis (RA) further confirmed its advantages in practice. SBS is a powerful and efficient gene-based method for detecting gene-gene co-association.

Chronic workplace stress and insufficient physical activity: a cohort study.

Science.gov (United States)

Kouvonen, Anne; Vahtera, Jussi; Oksanen, Tuula; Pentti, Jaana; Väänänen, Ari K P; Heponiemi, Tarja; Salo, Paula; Virtanen, Marianna; Kivimäki, Mika

2013-01-01

To examine whether exposure to workplace stressors predicts changes in physical activity and the risk of insufficient physical activity. Prospective data from the Finnish Public Sector Study. Repeated exposure to low job control, high job demands, low effort, low rewards and compositions of these (job strain and effort-reward imbalance) were assessed at Time 1 (2000-2002) and Time 2 (2004). Insufficient physical activity (workplace stressors on change in physical activity was examined using fixed-effects (within-subject) logistic regression models (N=6665). In addition, logistic regression analysis was applied to examine the associations between repeated exposure to workplace stressors and insufficient physical activity (N=13 976). In these analyses, coworker assessed workplace stressor scores were used in addition to individual level scores. The proportion of participants with insufficient physical activity was 24% at baseline and 26% at follow-up. 19% of the participants who were sufficiently active at baseline became insufficiently active at follow-up. In the fixed-effect analysis, an increase in workplace stress was weakly related to an increase in physical inactivity within an individual. In between-subjects analysis, employees with repeated exposure to low job control and low rewards were more likely to be insufficiently active at follow-up than those with no reports of these stressors; fully adjusted ORs ranged from 1.11 (95% CI 1.00 to 1.24) to 1.21 (95% CI 1.05 to 1.39). Workplace stress is associated with a slightly increased risk of physical inactivity.

Why Sleep Matters—The Economic Costs of Insufficient Sleep

Science.gov (United States)

Hafner, Marco; Stepanek, Martin; Taylor, Jirka; Troxel, Wendy M.; van Stolk, Christian

2017-01-01

Abstract The Centers for Disease Control and Prevention (CDC) in the United States has declared insufficient sleep a “public health problem.” Indeed, according to a recent CDC study, more than a third of American adults are not getting enough sleep on a regular basis. However, insufficient sleep is not exclusively a US problem, and equally concerns other industrialised countries such as the United Kingdom, Japan, Germany, or Canada. According to some evidence, the proportion of people sleeping less than the recommended hours of sleep is rising and associated with lifestyle factors related to a modern 24/7 society, such as psychosocial stress, alcohol consumption, smoking, lack of physical activity and excessive electronic media use, among others. This is alarming as insufficient sleep has been found to be associated with a range of negative health and social outcomes, including success at school and in the labour market. Over the last few decades, for example, there has been growing evidence suggesting a strong association between short sleep duration and elevated mortality risks. Given the potential adverse effects of insufficient sleep on health, well-being and productivity, the consequences of sleep-deprivation have far-reaching economic consequences. Hence, in order to raise awareness of the scale of insufficient sleep as a public-health issue, comparative quantitative figures need to be provided for policy- and decision-makers, as well as recommendations and potential solutions that can help tackling the problem. PMID:28983434

The power of statistical tests using field trial count data of non-target organisms in enviromental risk assessment of genetically modified plants

NARCIS (Netherlands)

Voet, van der H.; Goedhart, P.W.

2015-01-01

Publications on power analyses for field trial count data comparing transgenic and conventional crops have reported widely varying requirements for the replication needed to obtain statistical tests with adequate power. These studies are critically reviewed and complemented with a new simulation

Physiologic AV valvular insufficiency in cine MR imaging

Energy Technology Data Exchange (ETDEWEB)

Jang, Yoon Hyung; Kang, Eun Joo; Baik, Seung Kug; Ahn, Woo Hyun; Choi, Han Yong; Kim, Bong Gi [Wallace Memorial Baptist Hospital, Pusan (Korea, Republic of)

1994-05-15

To give a help in the interpretation of cardiac cine-MR examination, the extent, shape, and timing of appearance of signal void regions near atrioventricular(A-V) valve prospectively evaluate in the healthy population. Using an axial gradient-echo technique with small flip angle, repetition time(TR) of 36 msec and echo time(TE) of 22 msec, 20 volunteers without known valvular abnormalities undertook cardiac cine-MR imaging including atrioventricular valve areas. Transient signal void was observed within the near the tricuspid(13/20 = 65%) and mitral valves(9/20 = 45%), respectively, which is so called {sup p}hysioloic atrioventricular valvular insufficiency{sup .} Eight subjects revealed the signal void areas near both tricuspid and mitral valves but, 5 subjects did not show any evidence of physiologic insufficiency. This physiologic condition does not extend more than 1 cm proximal to A-V valve plane and is generally observed only during early systole. Its morphology is semilunar or triangular configuration with the base to the valve plane in most cases of normal tricuspid insufficiency and small globular appearance in most cases of normal mitral insufficiency. Awareness of normal signal void areas near the A-V valve and their characteristics is critical in the interpretation of cardiac cine MR examinations and maybe helpful in the study of the normal cardiac physiology.

Physiologic AV valvular insufficiency in cine MR imaging

International Nuclear Information System (INIS)

Jang, Yoon Hyung; Kang, Eun Joo; Baik, Seung Kug; Ahn, Woo Hyun; Choi, Han Yong; Kim, Bong Gi

1994-01-01

To give a help in the interpretation of cardiac cine-MR examination, the extent, shape, and timing of appearance of signal void regions near atrioventricular(A-V) valve prospectively evaluate in the healthy population. Using an axial gradient-echo technique with small flip angle, repetition time(TR) of 36 msec and echo time(TE) of 22 msec, 20 volunteers without known valvular abnormalities undertook cardiac cine-MR imaging including atrioventricular valve areas. Transient signal void was observed within the near the tricuspid(13/20 = 65%) and mitral valves(9/20 = 45%), respectively, which is so called p hysioloic atrioventricular valvular insufficiency . Eight subjects revealed the signal void areas near both tricuspid and mitral valves but, 5 subjects did not show any evidence of physiologic insufficiency. This physiologic condition does not extend more than 1 cm proximal to A-V valve plane and is generally observed only during early systole. Its morphology is semilunar or triangular configuration with the base to the valve plane in most cases of normal tricuspid insufficiency and small globular appearance in most cases of normal mitral insufficiency. Awareness of normal signal void areas near the A-V valve and their characteristics is critical in the interpretation of cardiac cine MR examinations and maybe helpful in the study of the normal cardiac physiology

Endovenous Laser Ablation as a Treatment for Postsurgical Recurrent Saphenous Insufficiency

International Nuclear Information System (INIS)

Anchala, Praveen R.; Wickman, Christopher; Chen, Richard; Faundeen, Tonya; Pearce, William; Narducy, Lisa; Resnick, Scott A.

2010-01-01

The purpose of this study was to investigate the safety and efficacy of endovenous laser ablation as a treatment for recurrent symptomatic saphenous insufficiency occurring after saphenous vein ligation and stripping. A single-center retrospective review of patients who received endovenous laser ablation as a treatment for recurrent symptomatic saphenous insufficiency after ligation and stripping between November 2003 and October 2006 was performed. Fifty-six insufficient saphenous systems were identified in 38 patients. Follow-up consisted of a clinical examination in all patients as well as selective lower-extremity duplex ultrasound as clinically indicated. All 38 patients demonstrated complete closure of the insufficient saphenous vein by clinical examination and/or duplex ultrasound evaluation. Preoperative symptoms resolved after treatment in all 38 patients. No major complications were identified. Endovenous laser ablation of recurrent symptomatic saphenous venous insufficiency is a safe and effective treatment in patients who develop recurrent symptoms after saphenous vein ligation and stripping.

IAEA releases nuclear power statistics for 2000

International Nuclear Information System (INIS)

2001-01-01

According to data reported to the IAEA Power Reactor Information System, a total of 438 NPPs were operating around the world at the end of 2000. The total installed power from NPPs was 351 GWe. During 2000, six plants were connected to the grid, construction of three new nuclear reactors started, bringing the total number of reactors under construction to 31. Worldwide in 2000, total nuclear generated electricity increased to 2447.53 terawatt-hours. Cumulative worldwide operating experience from civil nuclear power reactors at the end of 2000 exceeded 9800 reactor years

Hereditary myopathies with early respiratory insufficiency in adults.

Science.gov (United States)

Naddaf, Elie; Milone, Margherita

2017-11-01

Hereditary myopathies with early respiratory insufficiency as a predominant feature of the clinical phenotype are uncommon and underestimated in adults. We reviewed the clinical and laboratory data of patients with hereditary myopathies who demonstrated early respiratory insufficiency before the need for ambulatory assistance. Only patients with disease-causing mutations or a specific histopathological diagnosis were included. Patients with cardiomyopathy were excluded. We identified 22 patients; half had isolated respiratory symptoms at onset. The diagnosis of the myopathy was often delayed, resulting in delayed ventilatory support. The most common myopathies were adult-onset Pompe disease, myofibrillar myopathy, multi-minicore disease, and myotonic dystrophy type 1. Single cases of laminopathy, MELAS (mitochondrial encephalomyopathy with lactic acidosis and strokelike events), centronuclear myopathy, and cytoplasmic body myopathy were identified. We highlighted the most common hereditary myopathies associated with early respiratory insufficiency as the predominant clinical feature, and underscored the importance of a timely diagnosis for patient care. Muscle Nerve 56: 881-886, 2017. © 2017 Wiley Periodicals, Inc.

Venous compression syndrome of internal jugular veins prevalence in patients with multiple sclerosis and chronic cerebro-spinal venous insufficiency.

Science.gov (United States)

Mandolesi, Sandro; Niglio, Tarcisio; Orsini, Augusto; De Sio, Simone; d'Alessandro, Alessandro; Mandolesi, Dimitri; Fedele, Francesco; d'Alessandro, Aldo

2016-01-01

Analysis of the incidence of Venous Compression Syndrome (VCS) with full block of the flow of the internal jugular veins (IJVs) in patients with Multiple Sclerosis and Chronic cerebro-spinal venous insufficiency. We included 769 patients with MS and CCSVI (299 males, 470 females) and 210 controls without ms and ccsvi (92 males, 118 females). each subject was investigated by echo-color-doppler (ecd). morphological and hemodynamic ecd data were recorded by a computerized mem-net maps of epidemiological national observatory on ccsvi and they were analyzed by mem-net clinical analysis programs. VCS of IJVs occurs in 240 subjects affected by CCSVI and MS (31% of total) and in 12 controls (6% of total). The differences between the two groups are statistical significant (X² = 36.64, pCerebro-Spinal Venous Insufficiency, Multiple Sclerosis, Venous Compression Syndrome.

Ping-pong champion with adrenal insufficiency

Science.gov (United States)

Arima, Hiroshi; Imamine, Rui; Oiso, Yutaka

2009-01-01

A 62-year-old Japanese man, a bronze medal winner in the World Championship of table tennis when in his 20s, was diagnosed with secondary adrenocortical insufficiency due to isolated adrenocorticotropic hormone (ACTH) deficiency, and steroid administration was started. About 1 year after the diagnosis, he took part in a table tennis championship which was open to those 40 years or older. He took 10 mg hydrocortisone after breakfast as usual, played 10 matches, each of which took 20–30 min, and won the championship in about 8 h. Since the man could not always win the gruelling competition even when in his 50s, it is suggested that extra steroid hormone is not necessary for patients with adrenocortical insufficiency due to ACTH deficiency in order to successfully engage in sports requiring such intensity and endurance. PMID:21686433

[Traumatic tricuspid insufficiency].

Science.gov (United States)

Vayre, F; Richard, P; Ollivier, J P

1996-04-01

Traumatic tricuspid insufficiency is a rare condition. The diagnosis is difficult because of the slow progression of this pathology and the presence of more clinically acute lesions. Non-penetrating chest trauma is responsible for 90% of cases. Echocardiography is the investigation of choice for assessing the mechanism of the tricuspid regurgitation and for diagnosing associated lesions. It should be performed systematically in patients with multiple trauma. The surgical indications are difficult to determine and depend on the patients' symptoms and the type of anatomical lesions. It should be undertaken before right ventricular myocardial dysfunction. Several techniques may be used from valvuloplasty to valve replacement mainly with bioprostheses in symptomatic patients.

Statistical models for thermal ageing of steel materials in nuclear power plants

International Nuclear Information System (INIS)

Persoz, M.

1996-01-01

Some category of steel materials in nuclear power plants may be subjected to thermal ageing, whose extent depends on the steel chemical composition and the ageing parameters, i.e. temperature and duration. This ageing affects the 'impact strength' of the materials, which is a mechanical property. In order to assess the residual lifetime of these components, a probabilistic study has been launched, which takes into account the scatter over the input parameters of the mechanical model. Predictive formulae for estimating the impact strength of aged materials are important input data of the model. A data base has been created with impact strength results obtained from an ageing program in laboratory and statistical treatments have been undertaken. Two kinds of model have been developed, with non linear regression methods (PROC NLIN, available in SAS/STAT). The first one, using a hyperbolic tangent function, is partly based on physical considerations, and the second one, of an exponential type, is purely statistically built. The difficulties consist in selecting the significant parameters and attributing initial values to the coefficients, which is a requirement of the NLIN procedure. This global statistical analysis has led to general models that are unction of the chemical variables and the ageing parameters. These models are as precise (if not more) as local models that had been developed earlier for some specific values of ageing temperature and ageing duration. This paper describes the data and the methodology used to build the models and analyses the results given by the SAS system. (author)

Pancreatic fibrosis correlates with exocrine pancreatic insufficiency after pancreatoduodenectomy.

Science.gov (United States)

Tran, T C K; van 't Hof, G; Kazemier, G; Hop, W C; Pek, C; van Toorenenbergen, A W; van Dekken, H; van Eijck, C H J

2008-01-01

Obstruction of the pancreatic duct can lead to pancreatic fibrosis. We investigated the correlation between the extent of pancreatic fibrosis and the postoperative exocrine and endocrine pancreatic function. Fifty-five patients who were treated for pancreatic and periampullary carcinoma and 19 patients with chronic pancreatitis were evaluated. Exocrine pancreatic function was evaluated by fecal elastase-1 test, while endocrine pancreatic function was assessed by plasma glucose level. The extent of fibrosis, duct dilation and endocrine tissue loss was examined histopathologically. A strong correlation was found between pancreatic fibrosis and elastase-1 level less than 100 microg/g (p pancreatic insufficiency. A strong correlation was found between pancreatic fibrosis and endocrine tissue loss (p pancreatic fibrosis nor endocrine tissue loss were correlated with the development of postoperative diabetes mellitus. Duct dilation alone was neither correlated with exocrine nor with endocrine function loss. The majority of patients develop severe exocrine pancreatic insufficiency after pancreatoduodenectomy. The extent of exocrine pancreatic insufficiency is strongly correlated with preoperative fibrosis. The loss of endocrine tissue does not correlate with postoperative diabetes mellitus. Preoperative dilation of the pancreatic duct per se does not predict exocrine or endocrine pancreatic insufficiency postoperatively. Copyright 2008 S. Karger AG, Basel.

The Bayesian New Statistics: Hypothesis testing, estimation, meta-analysis, and power analysis from a Bayesian perspective.

Science.gov (United States)

Kruschke, John K; Liddell, Torrin M

2018-02-01

In the practice of data analysis, there is a conceptual distinction between hypothesis testing, on the one hand, and estimation with quantified uncertainty on the other. Among frequentists in psychology, a shift of emphasis from hypothesis testing to estimation has been dubbed "the New Statistics" (Cumming 2014). A second conceptual distinction is between frequentist methods and Bayesian methods. Our main goal in this article is to explain how Bayesian methods achieve the goals of the New Statistics better than frequentist methods. The article reviews frequentist and Bayesian approaches to hypothesis testing and to estimation with confidence or credible intervals. The article also describes Bayesian approaches to meta-analysis, randomized controlled trials, and power analysis.

[The influence of Helicobacter pylori infection on the occurance of gastroesophageal reflux in patients with renal insufficiency].

Science.gov (United States)

Stolić, Radojica; Jovanović, Aleksandar; Perić, Vladan; Trajković, Goran; Zivić, Ziva; Stolić, Dragica; Lazarević, Tatjana; Sovtić, Sasa

2007-12-01

Gastric acid is a key factor in the pathophysiology of gastroesophageal reflux disease. A plausible mechanism by which the Helicobacter pylori infection might protect against reflux disease is by its propensity to produce atrophic gastritis. The aim of the study was to establish the influence of Helicobacter pylori infection on the occurrence of gastroesophageal reflux in patients with different stages of renal insufficiency. The examination was organized as a prospective, clinical study and involved 68 patients--33 patients with preterminal stage of renal failure and 35 patients with terminal renal insufficiency. Due to dyspeptic difficulties, in all the patients there was preformed upper esophagogastroscopy and Helicobacter pylori infection was found by ureasa test. The patients with preterminal renal insufficiency were significantly younger than patients with terminal renal failure (53.4 +/- 11.1 vs. 65.4 +/- 12.3 years; p = 0.014). There was found a statistically significant difference between the groups in Helicobacter pylori infection (p = 0.03), hiatal hernia (p = 0.008), gastroesophageal reflux disease (p = 0.007), and duodenal ulcer (p = 0.002). Using the multiple non-parametric correlative analysis there was confirmed a negative correlation between Helicobacter pylori infection and gastro-esophageal reflux disease (Kendal tauB = -0.523; p = 0.003) and hiatal hernia (Kendal tauB = 0.403; p = 0.021), while there was found a positive correlation between gastro-esophageal reflux disease and hiatal hernia (Kendal tauB = 0.350; p = 0.044). Helicobacter pylori infection is a significant protective parameter of the incidence of gastro-esophageal reflux disease in patients with both pre-terminal and terminal renal insufficiency.

The influence of Helicobacter pylori infection on the occurrence of gastroesophageal reflux in patients with renal insufficiency

Directory of Open Access Journals (Sweden)

Stolić Radojica

2007-01-01

Full Text Available Introduction/Aim. Gastric acid is a key factor in the pathophysiology of gastroesophageal reflux disease. A plausible mechanism by which the Helicobacter pylori infection might protect against reflux disease is by its propensity to produce atrophic gastritis. The aim of the study was to establish the influence of Helicobacter pylori infection on the occurrence of gastroesophageal reflux in patients with different stages of renal insufficiency. Methods. The examination was organized as a prospective, clinical study and involved 68 patients − 33 patients with preterminal stage of renal failure and 35 patients with terminal renal insufficiency. Due to dyspeptic difficulties, in all the patients there was preformed upper esophagogastroscopy and Helicobacter pylori infection was found by ureasa test. Results. The patients with preterminal renal insufficiency were significantly younger than patients with terminal renal failure (53.4±11.1 vs. 65.4±12.3 years; p = 0.014. There was found a statistically significant difference between the groups in Helicobacter pylori infection (p = 0.03, hiatal hernia (p = 0.008, gastroesophageal reflux disease (p = 0.007, and duodenal ulcer (p = 0.002. Using the multiple non-parametric correlative analysis there was confirmed a negative correlation between Helicobacter pylori infection and gastro-esophageal reflux disease (Kendal τB = -0.523; p = 0.003 and hiatal hernia (Kendal τB = 0.403; p = 0.021, while there was found a positive correlation between gastro-esophageal reflux disease and hiatal hernia (Kendal τB = 0.350; p = 0.044. Conclusion. Helicobacter pylori infection is a significant protective parameter of the incidence of gastro-esophageal reflux disease in patients with both pre-terminal and terminal renal insufficiency.

Sparse Power-Law Network Model for Reliable Statistical Predictions Based on Sampled Data

Directory of Open Access Journals (Sweden)

Alexander P. Kartun-Giles

2018-04-01

Full Text Available A projective network model is a model that enables predictions to be made based on a subsample of the network data, with the predictions remaining unchanged if a larger sample is taken into consideration. An exchangeable model is a model that does not depend on the order in which nodes are sampled. Despite a large variety of non-equilibrium (growing and equilibrium (static sparse complex network models that are widely used in network science, how to reconcile sparseness (constant average degree with the desired statistical properties of projectivity and exchangeability is currently an outstanding scientific problem. Here we propose a network process with hidden variables which is projective and can generate sparse power-law networks. Despite the model not being exchangeable, it can be closely related to exchangeable uncorrelated networks as indicated by its information theory characterization and its network entropy. The use of the proposed network process as a null model is here tested on real data, indicating that the model offers a promising avenue for statistical network modelling.

Diagnosis and management of pancreatic exocrine insufficiency.

Science.gov (United States)

Nikfarjam, Mehrdad; Wilson, Jeremy S; Smith, Ross C

2017-08-21

In 2015, the Australasian Pancreatic Club (APC) published the Australasian guidelines for the management of pancreatic exocrine insufficiency (http://pancreas.org.au/2016/01/pancreatic-exocrine-insufficiency-guidelines). Pancreatic exocrine insufficiency (PEI) occurs when normal digestion cannot be sustained due to insufficient pancreatic digestive enzyme activity. This may be related to a breakdown, at any point, in the pancreatic digestive chain: pancreatic stimulation; synthesis, release or transportation of pancreatic enzymes; or synchronisation of secretions to mix with ingested food. Main recommendations: The guidelines provide advice on diagnosis and management of PEI, noting the following: A high prevalence of PEI is seen in certain diseases and conditions, such as cystic fibrosis, acute and chronic pancreatitis, pancreatic cancer and pancreatic surgery. The main symptoms of PEI are steatorrhoea or diarrhoea, abdominal pain, bloating and weight loss. These symptoms are non-specific and often go undetected and untreated. PEI diagnosis is predominantly based on clinical findings and the presence of underlying disease. The likelihood of PEI in suspected patients has been categorised into three groups: definite, possible and unlikely. If left untreated, PEI may lead to complications related to fat malabsorption and malnutrition, and have an impact on quality of life. Pancreatic enzyme replacement therapy (PERT) remains the mainstay of PEI treatment with the recommended adult initial enzyme dose being 25 000-40 000 units of lipase per meal, titrating up to a maximum of 75 000-80 000 units of lipase per meal. Adjunct acid-suppressing therapy may be useful when patients still experience symptoms of PEI on high dose PERT. Nutritional management by an experienced dietitian is essential. Changes in management as a result of these guidelines: These are the first guidelines to classify PEI as being definite, possible or unlikely, and provide a diagnostic algorithm to

Statistical Analysis of Solar PV Power Frequency Spectrum for Optimal Employment of Building Loads

Energy Technology Data Exchange (ETDEWEB)

Olama, Mohammed M [ORNL; Sharma, Isha [ORNL; Kuruganti, Teja [ORNL; Fugate, David L [ORNL

2017-01-01

In this paper, a statistical analysis of the frequency spectrum of solar photovoltaic (PV) power output is conducted. This analysis quantifies the frequency content that can be used for purposes such as developing optimal employment of building loads and distributed energy resources. One year of solar PV power output data was collected and analyzed using one-second resolution to find ideal bounds and levels for the different frequency components. The annual, seasonal, and monthly statistics of the PV frequency content are computed and illustrated in boxplot format. To examine the compatibility of building loads for PV consumption, a spectral analysis of building loads such as Heating, Ventilation and Air-Conditioning (HVAC) units and water heaters was performed. This defined the bandwidth over which these devices can operate. Results show that nearly all of the PV output (about 98%) is contained within frequencies lower than 1 mHz (equivalent to ~15 min), which is compatible for consumption with local building loads such as HVAC units and water heaters. Medium frequencies in the range of ~15 min to ~1 min are likely to be suitable for consumption by fan equipment of variable air volume HVAC systems that have time constants in the range of few seconds to few minutes. This study indicates that most of the PV generation can be consumed by building loads with the help of proper control strategies, thereby reducing impact on the grid and the size of storage systems.

Power of mental health nursing research: a statistical analysis of studies in the International Journal of Mental Health Nursing.

Science.gov (United States)

Gaskin, Cadeyrn J; Happell, Brenda

2013-02-01

Having sufficient power to detect effect sizes of an expected magnitude is a core consideration when designing studies in which inferential statistics will be used. The main aim of this study was to investigate the statistical power in studies published in the International Journal of Mental Health Nursing. From volumes 19 (2010) and 20 (2011) of the journal, studies were analysed for their power to detect small, medium, and large effect sizes, according to Cohen's guidelines. The power of the 23 studies included in this review to detect small, medium, and large effects was 0.34, 0.79, and 0.94, respectively. In 90% of papers, no adjustments for experiment-wise error were reported. With a median of nine inferential tests per paper, the mean experiment-wise error rate was 0.51. A priori power analyses were only reported in 17% of studies. Although effect sizes for correlations and regressions were routinely reported, effect sizes for other tests (χ(2)-tests, t-tests, ANOVA/MANOVA) were largely absent from the papers. All types of effect sizes were infrequently interpreted. Researchers are strongly encouraged to conduct power analyses when designing studies, and to avoid scattergun approaches to data analysis (i.e. undertaking large numbers of tests in the hope of finding 'significant' results). Because reviewing effect sizes is essential for determining the clinical significance of study findings, researchers would better serve the field of mental health nursing if they reported and interpreted effect sizes. © 2012 The Authors. International Journal of Mental Health Nursing © 2012 Australian College of Mental Health Nurses Inc.

Health consequences of shift work and insufficient sleep.

Science.gov (United States)

Kecklund, Göran; Axelsson, John

2016-11-01

This review summarises the literature on shift work and its relation to insufficient sleep, chronic diseases, and accidents. It is based on 38 meta-analyses and 24 systematic reviews, with additional narrative reviews and articles used for outlining possible mechanisms by which shift work may cause accidents and adverse health. Evidence shows that the effect of shift work on sleep mainly concerns acute sleep loss in connection with night shifts and early morning shifts. A link also exists between shift work and accidents, type 2 diabetes (relative risk range 1.09-1.40), weight gain, coronary heart disease (relative risk 1.23), stroke (relative risk 1.05), and cancer (relative risk range 1.01-1.32), although the original studies showed mixed results. The relations of shift work to cardiometabolic diseases and accidents mimic those with insufficient sleep. Laboratory studies indicate that cardiometabolic stress and cognitive impairments are increased by shift work, as well as by sleep loss. Given that the health and safety consequences of shift work and insufficient sleep are very similar, they are likely to share common mechanisms. However, additional research is needed to determine whether insufficient sleep is a causal pathway for the adverse health effects associated with shift work. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Dark matter statistics for large galaxy catalogs: power spectra and covariance matrices

Science.gov (United States)

Klypin, Anatoly; Prada, Francisco

2018-06-01

Large-scale surveys of galaxies require accurate theoretical predictions of the dark matter clustering for thousands of mock galaxy catalogs. We demonstrate that this goal can be achieve with the new Parallel Particle-Mesh (PM) N-body code GLAM at a very low computational cost. We run ˜22, 000 simulations with ˜2 billion particles that provide ˜1% accuracy of the dark matter power spectra P(k) for wave-numbers up to k ˜ 1hMpc-1. Using this large data-set we study the power spectrum covariance matrix. In contrast to many previous analytical and numerical results, we find that the covariance matrix normalised to the power spectrum C(k, k΄)/P(k)P(k΄) has a complex structure of non-diagonal components: an upturn at small k, followed by a minimum at k ≈ 0.1 - 0.2 hMpc-1, and a maximum at k ≈ 0.5 - 0.6 hMpc-1. The normalised covariance matrix strongly evolves with redshift: C(k, k΄)∝δα(t)P(k)P(k΄), where δ is the linear growth factor and α ≈ 1 - 1.25, which indicates that the covariance matrix depends on cosmological parameters. We also show that waves longer than 1h-1Gpc have very little impact on the power spectrum and covariance matrix. This significantly reduces the computational costs and complexity of theoretical predictions: relatively small volume ˜(1h-1Gpc)3 simulations capture the necessary properties of dark matter clustering statistics. As our results also indicate, achieving ˜1% errors in the covariance matrix for k < 0.50 hMpc-1 requires a resolution better than ɛ ˜ 0.5h-1Mpc.

Application of a Statistical Linear Time-Varying System Model of High Grazing Angle Sea Clutter for Computing Interference Power

Science.gov (United States)

2017-12-08

STATISTICAL LINEAR TIME-VARYING SYSTEM MODEL OF HIGH GRAZING ANGLE SEA CLUTTER FOR COMPUTING INTERFERENCE POWER 1. INTRODUCTION Statistical linear time...beam. We can approximate one of the sinc factors using the Dirichlet kernel to facilitate computation of the integral in (6) as follows: ∣∣∣∣sinc(WB...plotted in Figure 4. The resultant autocorrelation can then be found by substituting (18) into (28). The Python code used to generate Figures 1-4 is found

A multivariate statistical methodology for detection of degradation and failure trends using nuclear power plant operational data

International Nuclear Information System (INIS)

Samanta, P.K.; Teichmann, T.

1990-01-01

In this paper, a multivariate statistical method is presented and demonstrated as a means for analyzing nuclear power plant transients (or events) and safety system performance for detection of malfunctions and degradations within the course of the event based on operational data. The study provides the methodology and illustrative examples based on data gathered from simulation of nuclear power plant transients (due to lack of easily accessible operational data). Such an approach, once fully developed, can be used to detect failure trends and patterns and so can lead to prevention of conditions with serious safety implications

Statistical tables 2003

International Nuclear Information System (INIS)

2003-01-01

The energy statistical table is a selection of statistical data for energies and countries from 1997 to 2002. It concerns the petroleum, the natural gas, the coal, the electric power, the production, the external market, the consumption per sector, the energy accounting 2002 and graphs on the long-dated forecasting. (A.L.B.)

Harmonic statistics

International Nuclear Information System (INIS)

Eliazar, Iddo

2017-01-01

The exponential, the normal, and the Poisson statistical laws are of major importance due to their universality. Harmonic statistics are as universal as the three aforementioned laws, but yet they fall short in their ‘public relations’ for the following reason: the full scope of harmonic statistics cannot be described in terms of a statistical law. In this paper we describe harmonic statistics, in their full scope, via an object termed harmonic Poisson process: a Poisson process, over the positive half-line, with a harmonic intensity. The paper reviews the harmonic Poisson process, investigates its properties, and presents the connections of this object to an assortment of topics: uniform statistics, scale invariance, random multiplicative perturbations, Pareto and inverse-Pareto statistics, exponential growth and exponential decay, power-law renormalization, convergence and domains of attraction, the Langevin equation, diffusions, Benford’s law, and 1/f noise. - Highlights: • Harmonic statistics are described and reviewed in detail. • Connections to various statistical laws are established. • Connections to perturbation, renormalization and dynamics are established.

Harmonic statistics

Energy Technology Data Exchange (ETDEWEB)

Eliazar, Iddo, E-mail: eliazar@post.tau.ac.il

2017-05-15

The exponential, the normal, and the Poisson statistical laws are of major importance due to their universality. Harmonic statistics are as universal as the three aforementioned laws, but yet they fall short in their ‘public relations’ for the following reason: the full scope of harmonic statistics cannot be described in terms of a statistical law. In this paper we describe harmonic statistics, in their full scope, via an object termed harmonic Poisson process: a Poisson process, over the positive half-line, with a harmonic intensity. The paper reviews the harmonic Poisson process, investigates its properties, and presents the connections of this object to an assortment of topics: uniform statistics, scale invariance, random multiplicative perturbations, Pareto and inverse-Pareto statistics, exponential growth and exponential decay, power-law renormalization, convergence and domains of attraction, the Langevin equation, diffusions, Benford’s law, and 1/f noise. - Highlights: • Harmonic statistics are described and reviewed in detail. • Connections to various statistical laws are established. • Connections to perturbation, renormalization and dynamics are established.

Association Between Vitamin D Insufficiency and Metabolic Syndrome in Patients With Psychotic Disorders.

Science.gov (United States)

Yoo, Taeyoung; Choi, Wonsuk; Hong, Jin-Hee; Lee, Ju-Yeon; Kim, Jae-Min; Shin, Il-Seon; Yang, Soo Jin; Amminger, Paul; Berk, Michael; Yoon, Jin-Sang; Kim, Sung-Wan

2018-04-01

This study examined the association between vitamin D and metabolic syndrome in patients with psychotic disorders. The study enrolled 302 community-dwelling patients with psychotic disorders. Sociodemographic and clinical characteristics, including blood pressure, physical activity, and dietary habit were gathered. Laboratory examinations included vitamin D, lipid profile, fasting plasma glucose, HbA1c, liver function, and renal function. Vitamin D insufficiency was defined as vitamin D insufficiency were identified. Among the 302 participants, 236 patients (78.1%) had a vitamin D insufficiency and 97 (32.1%) had metabolic syndrome. Vitamin D insufficiency was significantly associated with the presence of metabolic syndrome (p=0.006) and hypertension (p=0.017). Significant increases in triglycerides and alanine transaminase were observed in the group with a vitamin D insufficiency (p=0.002 and 0.011, respectively). After adjusting for physical activity and dietary habit scores, vitamin D insufficiency remained significantly associated with metabolic syndrome and hypertension. Vitamin D insufficiency was associated with metabolic syndrome and was particularly associated with high blood pressure, although the nature, direction and implications of this association are unclear.

Nuclear power prospects in Finland

International Nuclear Information System (INIS)

1961-01-01

The basic circumstances which stimulated Finland's interest in nuclear power are summarized in the report as follows: 'In Finland the main power resource has been, and still is, water power. It is clear, however, that the hydro potential is insufficient to cover the increasing consumption over a long period of time. Already about one half of this potential has been exploited. Thus the country will necessarily have to consider the utilization of thermal power to an increasingly large extent. There is no indigenous coal or oil. For this reason it has become necessary to investigate realistically the possibilities offered by nuclear power'

Effectiveness of vision therapy in school children with symptomatic convergence insufficiency

Directory of Open Access Journals (Sweden)

Jung Un Jang

2017-01-01

Conclusion: Among convergence insufficiency symptoms, the following improved in particular: near point of convergence, exophoria, and near positive fusional vergence. These findings suggest that vision therapy is very effective to recover from symptomatic convergence insufficiency.

Leptomeningeal dissemination of an astrocytoma causing hypophyseal insufficiency

International Nuclear Information System (INIS)

Suzan, S.; Cigdem, O.; Furkan, U.; Baki, A.

2012-01-01

Full text: Introduction: Hypophyseal insufficiency is an unusual clinical presentation of metastatic disease. Objectives: In this report, a case of leptomeningeal metastasis of an astrocytoma to the infundibular recess, causing hypophyseal insufficiency is presented with its magnetic resonance imaging (MRI) findings. Materials and methods: A 27-year-old woman presented with nausea, vomiting and generalized weakness. Her laboratory results were consistent with hypopituitarism. She had an operation history for astrocytoma. She was referred to radiology department for brain MRI study. Contrast-enhanced MRI scan showed extensive wall enhancement of ventricles consistent with leptomeningeal metastases. A nodular mass with pronounced contrast enhancement was also detected at the infundibular stalk. Results: Because suprasellar cistern was normal and extensive leptomeningeal metastases was detected, the nodular mass at the infundibular stalk thought to be secondary to leptomeningeal involvement of the infundibular recess. Conclusion: When a patient with a known malignancy presented with hypophyseal insufficiency, it should be thought that leptomeningeal metastases to the infundibular recess may also be a cause. The neuroimaging, especially contrast-enhanced studies, is necessary for the confirmation

Applying contemporary statistical techniques

CERN Document Server

Wilcox, Rand R

2003-01-01

Applying Contemporary Statistical Techniques explains why traditional statistical methods are often inadequate or outdated when applied to modern problems. Wilcox demonstrates how new and more powerful techniques address these problems far more effectively, making these modern robust methods understandable, practical, and easily accessible.* Assumes no previous training in statistics * Explains how and why modern statistical methods provide more accurate results than conventional methods* Covers the latest developments on multiple comparisons * Includes recent advanc

Visualization of traumatic tricuspid insufficiency by three-dimensional echocardiography.

Science.gov (United States)

Nishimura, Kazuhisa; Okayama, Hideki; Inoue, Katsuji; Saito, Makoto; Nagai, Takayuki; Suzuki, Jun; Ogimoto, Akiyoshi; Ohtsuka, Tomoaki; Higaki, Jitsuo

2010-01-01

A 19-year-old male was admitted to the emergency room of our hospital after a motor vehicle accident. During his first physical examination, a holosystolic murmur was heard at the fourth left parasternal border. Transthoracic echocardiography showed severe tricuspid insufficiency, but the cause of tricuspid insufficiency was unclear. Therefore, three-dimensional echocardiography was performed and demonstrated flail anterior, posterior and septal leaflets of the tricuspid valve. The diagnosis was tricuspid insufficiency due to papillary muscle rupture secondary to chest blunt trauma. Surgical repair of the tricuspid valve was performed in this patient. After surgery, the signs and symptoms of right ventricular heart failure were relieved. In this case, three-dimensional echocardiography was very useful for the evaluation of spatial destruction of the tricuspid valve and papillary muscle. 2009 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Nuclear power plant insurance - experience and loss statistics

International Nuclear Information System (INIS)

Feldmann, J.; Dangelmaier, P.

1982-01-01

Nuclear power plants are treated separately when concluding insurance contracts. National insurance pools have been established in industrial countries, co-operating on an international basis, for insuring a nuclear power plant. In combined property insurance, the nuclear risk is combined with the fire risk. In addition, there are the engineering insurances. Of these, the one of significance for nuclear power plants is the machinery insurance, which can be covered on the free insurance market. Nuclear power plants have had fewer instances of damage than other, conventional installations. (orig.) [de

Insufficiency fracture of the pelvis after the radiotherapy for carcinoma of the uterine cervix

International Nuclear Information System (INIS)

Nishimura, Tetsuo; Shimizu, Teppei; Sugiyama, Akira; Ichinohe, Kenji; Teshima, Takeshi; Takahashi, Motoichiro; Takai, Michikatsu; Kaneko, Masao

1990-01-01

Bone injury after radiotherapy for carcinoma of the uterine cervix has been reported since early days of this century. Recently, the concept of insufficiency fracture has been confirmed. Insufficiency fracture is one of the stress fractures and occurs when the elastic resistance of bone is inadequate to withstand normal or physiological stress. In the American and European studies, radiotherapy is known as a cause of insufficiency fracture. There are no reports on insufficiency fracture in the Japanese literatures. Four cases of carcinomas of the uterine cervix presented pelvic insufficiency fractures following radiotherapy. In the pubic bone, a vertical parasymphyseal fracture with mixed lytic and sclerotic changes of surrounding tissue is characteristic. Sacral insufficiency fracture shows a vertical or horizontal line with lytic and sclerotic appearance. Bone scintigraphy is a sensitive modality for the early detection. H-shaped configuration is diagnostic for sacral insufficiency fracture. CT is an accurate technique demonstrating a vertical fracture and excluding the malignant bony lesion. Although radiological findings of insufficiency fracture are similar to bone malignancy, differential diagnosis from malignant lesions is possible. Bony symptoms of all patients disappeared without specific treatments. In the follow-up study of patients with carcinomas of the uterine cervix after radiotherapy, it is important to have the consideration on insufficiency fracture. (author)

Statistics for products of traces of high powers of the frobenius class of hyperelliptic curves

OpenAIRE

Roditty-Gershon, Edva

2011-01-01

We study the averages of products of traces of high powers of the Frobenius class of hyperelliptic curves of genus g over a fixed finite field. We show that for increasing genus g, the limiting expectation of these products equals to the expectation when the curve varies over the unitary symplectic group USp(2g). We also consider the scaling limit of linear statistics for eigenphases of the Frobenius class of hyperelliptic curves, and show that their first few moments are Gaussian.

Recurrent Tricuspid Insufficiency: Is the Surgical Repair Technique a Risk Factor?

OpenAIRE

Kara, Ibrahim; Koksal, Cengiz; Cakalagaoglu, Canturk; Sahin, Muslum; Yanartas, Mehmet; Ay, Yasin; Demir, Serdar

2013-01-01

This study compares the medium-term results of De Vega, modified De Vega, and ring annuloplasty techniques for the correction of tricuspid insufficiency and investigates the risk factors for recurrent grades 3 and 4 tricuspid insufficiency after repair.

Statistical power and utility of meta-analysis methods for cross-phenotype genome-wide association studies.

Science.gov (United States)

Zhu, Zhaozhong; Anttila, Verneri; Smoller, Jordan W; Lee, Phil H

2018-01-01

Advances in recent genome wide association studies (GWAS) suggest that pleiotropic effects on human complex traits are widespread. A number of classic and recent meta-analysis methods have been used to identify genetic loci with pleiotropic effects, but the overall performance of these methods is not well understood. In this work, we use extensive simulations and case studies of GWAS datasets to investigate the power and type-I error rates of ten meta-analysis methods. We specifically focus on three conditions commonly encountered in the studies of multiple traits: (1) extensive heterogeneity of genetic effects; (2) characterization of trait-specific association; and (3) inflated correlation of GWAS due to overlapping samples. Although the statistical power is highly variable under distinct study conditions, we found the superior power of several methods under diverse heterogeneity. In particular, classic fixed-effects model showed surprisingly good performance when a variant is associated with more than a half of study traits. As the number of traits with null effects increases, ASSET performed the best along with competitive specificity and sensitivity. With opposite directional effects, CPASSOC featured the first-rate power. However, caution is advised when using CPASSOC for studying genetically correlated traits with overlapping samples. We conclude with a discussion of unresolved issues and directions for future research.

Contingency strategy for insufficient full core off load capability in spent fuel pool for Chinshan nuclear power station

International Nuclear Information System (INIS)

Huang, Pinghue

2012-01-01

The spent fuel pool (SFP) at Taiwan Power Company's (TUC's) Chinshan plant lost the full core off load (FCO) capability in 2010, even with the second SFP repacking project to expand the capacity as reported in 12PBNC. The TEPC had originally planned to move some spent fuel assemblies from SFP to dry storage facility, however, the dry storage project had seriously fell behind. Thus, it is required to address insufficient FCO capability, and the following contingency measures have been employed: The first step was to explore whether there was a specific regulatory requirement for FCO capability, and none were identified. Also, the industrial experiences were explored. The refueling strategy is changed from FCO to in-core shuffling. A feasibility evaluation performed indicates the Technical Specifications require: alternate method of decay heat removal, and verification of shutdown margin for each in vessel fuel movement. Specific methods have been successfully established. A safety evaluation for operation without FCO capability was performed, and no safety concerns were identified. The risk for operation without FCO capability was assessed. The previous operational experiences were identified. Moreover, such works are not expected in subsequent cycles. The new fuel vault is used to store new fuel assemblies. The criticality analysis has been performed and some new approaches are proposed to enhance the storage flexibility as reported in 17PBNC. An inter-unit transfer cask has been designed to transfer spent fuel from the SFP of one unit to the other. The FCO capability can be effectively extended for three more years with this consideration. The TPC discussed the contingency strategy with the ROCAEC in May 2006, and the ROCAEC's concurrence was attained. With the proposed strategy, Chinshan units have been operating smoothly

Contingency strategy for insufficient full core off load capability in spent fuel pool for Chinshan nuclear power station

Energy Technology Data Exchange (ETDEWEB)

Huang, Pinghue [Taiwan Power Company, Taipei (China)

2012-03-15

The spent fuel pool (SFP) at Taiwan Power Company's (TUC's) Chinshan plant lost the full core off load (FCO) capability in 2010, even with the second SFP repacking project to expand the capacity as reported in 12PBNC. The TEPC had originally planned to move some spent fuel assemblies from SFP to dry storage facility, however, the dry storage project had seriously fell behind. Thus, it is required to address insufficient FCO capability, and the following contingency measures have been employed: The first step was to explore whether there was a specific regulatory requirement for FCO capability, and none were identified. Also, the industrial experiences were explored. The refueling strategy is changed from FCO to in-core shuffling. A feasibility evaluation performed indicates the Technical Specifications require: alternate method of decay heat removal, and verification of shutdown margin for each in vessel fuel movement. Specific methods have been successfully established. A safety evaluation for operation without FCO capability was performed, and no safety concerns were identified. The risk for operation without FCO capability was assessed. The previous operational experiences were identified. Moreover, such works are not expected in subsequent cycles. The new fuel vault is used to store new fuel assemblies. The criticality analysis has been performed and some new approaches are proposed to enhance the storage flexibility as reported in 17PBNC. An inter-unit transfer cask has been designed to transfer spent fuel from the SFP of one unit to the other. The FCO capability can be effectively extended for three more years with this consideration. The TPC discussed the contingency strategy with the ROCAEC in May 2006, and the ROCAEC's concurrence was attained. With the proposed strategy, Chinshan units have been operating smoothly.

Modern applied statistics with S-plus

CERN Document Server

Venables, W N

1994-01-01

S-Plus is a powerful environment for statistical and graphical analysis of data. It provides the tools to implement many statistical ideas which have been made possible by the widespread availability of workstations having good graphics and computational capabilities. This book is a guide to using S-Plus to perform statistical analyses and provides both an introduction to the use of S-Plus and a course in modern statistical methods. The aim of the book is to show how to use S-Plus as a powerful and graphical system. Readers are assumed to have a basic grounding in statistics, and so the book is intended for would-be users of S-Plus, and both students and researchers using statistics. Throughout, the emphasis is on presenting practical problems and full analyses of real data sets.

The N-Pact Factor: Evaluating the Quality of Empirical Journals with Respect to Sample Size and Statistical Power

Science.gov (United States)

Fraley, R. Chris; Vazire, Simine

2014-01-01

The authors evaluate the quality of research reported in major journals in social-personality psychology by ranking those journals with respect to their N-pact Factors (NF)—the statistical power of the empirical studies they publish to detect typical effect sizes. Power is a particularly important attribute for evaluating research quality because, relative to studies that have low power, studies that have high power are more likely to (a) to provide accurate estimates of effects, (b) to produce literatures with low false positive rates, and (c) to lead to replicable findings. The authors show that the average sample size in social-personality research is 104 and that the power to detect the typical effect size in the field is approximately 50%. Moreover, they show that there is considerable variation among journals in sample sizes and power of the studies they publish, with some journals consistently publishing higher power studies than others. The authors hope that these rankings will be of use to authors who are choosing where to submit their best work, provide hiring and promotion committees with a superior way of quantifying journal quality, and encourage competition among journals to improve their NF rankings. PMID:25296159

Diagnosis of tricuspid insufficiency by Doppler flowmetry in the inferior vena cava

International Nuclear Information System (INIS)

Smith, H.J.

1986-01-01

Eighty-five patients subjected to routine heart catheterization were examined with duplex scanning of the inferior vena cava. Adequate Doppler recordings and a right ventricular angiography were obtained in 79 of them. Tricuspid insufficiency was found to be present in 34 patients at angiography and in 24 at duplex examination. No false positive Doppler diagnoses of tricuspid insufficiency occurred. The possibility of false positive angiographic diagnoses is discussed. A high correlation was found between percentage reversed flow in the inferior vena cava during ventricular systole and degree of angiographic tricuspid insufficiency. It is concluded that duplex scanning of the inferior vena cava seems to be a good alternative to angiography in the diagnosis and quantification of tricuspid insufficiency. (orig.)

Research on the relativity between gene polymorphism and children cardiac insufficiency.

Science.gov (United States)

He, X-H; Li, C-L; Ling, N; Wang, Q-W; Wang, Z-Z; An, X-J

2017-08-01

We analyzed the relationship between Mink-S27 gene polymorphism and children with cardiac insufficiency. From April 2013 to April 2015, we enrolled 73 cases of children with cardiac insufficiency for this study, and all 73 were placed in the observation group. 76 normal cases were selected for the control group. Restriction fragment length polymorphism (RFLP) was used to make polymorphism analysis of the Mink-S27. Our results showed no significant differences in Mink-S27 genotype and allele distribution in both observation and control groups (p>0.05). In lesion samples collected from children with cardiac insufficiency, we detected significant difference in AA, CC genotype frequency and allele frequency between the observation group and the control group (prelatively high. GNAS2 gene polymorphism was associated with the prevalence of cardiac insufficiency in children. And also the patients' condition was correlated to the frequency of different genotypes and alleles.

Statistical analysis of fuel failures in large break loss-of-coolant accident (LBLOCA) in EPR type nuclear power plant

International Nuclear Information System (INIS)

Arkoma, Asko; Hänninen, Markku; Rantamäki, Karin; Kurki, Joona; Hämäläinen, Anitta

2015-01-01

Highlights: • The number of failing fuel rods in a LB-LOCA in an EPR is evaluated. • 59 scenarios are simulated with the system code APROS. • 1000 rods per scenario are simulated with the fuel performance code FRAPTRAN-GENFLO. • All the rods in the reactor are simulated in the worst scenario. • Results suggest that the regulations set by the Finnish safety authority are met. - Abstract: In this paper, the number of failing fuel rods in a large break loss-of-coolant accident (LB-LOCA) in EPR-type nuclear power plant is evaluated using statistical methods. For this purpose, a statistical fuel failure analysis procedure has been developed. The developed method utilizes the results of nonparametric statistics, the Wilks’ formula in particular, and is based on the selection and variation of parameters that are important in accident conditions. The accident scenario is simulated with the coupled fuel performance – thermal hydraulics code FRAPTRAN-GENFLO using various parameter values and thermal hydraulic and power history boundary conditions between the simulations. The number of global scenarios is 59 (given by the Wilks’ formula), and 1000 rods are simulated in each scenario. The boundary conditions are obtained from a new statistical version of the system code APROS. As a result, in the worst global scenario, 1.2% of the simulated rods failed, and it can be concluded that the Finnish safety regulations are hereby met (max. 10% of the rods allowed to fail)

Statistical analysis of fuel failures in large break loss-of-coolant accident (LBLOCA) in EPR type nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Arkoma, Asko, E-mail: asko.arkoma@vtt.fi; Hänninen, Markku; Rantamäki, Karin; Kurki, Joona; Hämäläinen, Anitta

2015-04-15

Highlights: • The number of failing fuel rods in a LB-LOCA in an EPR is evaluated. • 59 scenarios are simulated with the system code APROS. • 1000 rods per scenario are simulated with the fuel performance code FRAPTRAN-GENFLO. • All the rods in the reactor are simulated in the worst scenario. • Results suggest that the regulations set by the Finnish safety authority are met. - Abstract: In this paper, the number of failing fuel rods in a large break loss-of-coolant accident (LB-LOCA) in EPR-type nuclear power plant is evaluated using statistical methods. For this purpose, a statistical fuel failure analysis procedure has been developed. The developed method utilizes the results of nonparametric statistics, the Wilks’ formula in particular, and is based on the selection and variation of parameters that are important in accident conditions. The accident scenario is simulated with the coupled fuel performance – thermal hydraulics code FRAPTRAN-GENFLO using various parameter values and thermal hydraulic and power history boundary conditions between the simulations. The number of global scenarios is 59 (given by the Wilks’ formula), and 1000 rods are simulated in each scenario. The boundary conditions are obtained from a new statistical version of the system code APROS. As a result, in the worst global scenario, 1.2% of the simulated rods failed, and it can be concluded that the Finnish safety regulations are hereby met (max. 10% of the rods allowed to fail)

Toward a more social social psychology of power

NARCIS (Netherlands)

Lammers, J.

2008-01-01

In this dissertation I aim to take a step toward a more social social psychology of power. In my opinion the existing social psychology on power is insufficiently social, and too material and physical. I believe this material and physical view has greatly influenced how social psychology has studied

Reactor power control system

International Nuclear Information System (INIS)

Tomisawa, Teruaki.

1981-01-01

Purpose: To restore reactor-power condition in a minimum time after a termination of turbine bypass by reducing the throttling of the reactor power at the time of load-failure as low as possible. Constitution: The transient change of the internal pressure of condenser is continuously monitored. When a turbine is bypassed, a speed-control-command signal for a coolant recirculating pump is generated according as the internal pressure of the condenser. When the signal relating to the internal pressure of the condenser indicates insufficient power, a reactor-control-rod-drive signal is generated. (J.P.N.)

Traumatic Tricuspid Insufficiency Requiring Valve Repair in an Acute Setting.

Science.gov (United States)

Enomoto, Yoshinori; Sudo, Yoshio; Sueta, Tomonori

2015-01-01

Tricuspid insufficiency due to penetrating cardiac trauma is rare. Patients with tricuspid insufficiency due to trauma can tolerate this abnormality for months or even years. We report a case of a 66-year-old female with penetrating cardiac trauma on the right side of her heart that required tricuspid valve repair in an acute setting. She sustained cut and stab wounds on her bilateral forearms and in the neck and epigastric region. She had cardiac tamponade and developed pulseless electrical activity, which required emergency surgery. The right ventricle and superior vena cava were dissected approximately 5 cm and 2 cm, respectively. After these wounds had been repaired, the patient's inability to wean from cardiopulmonary bypass suggested rightsided heart failure; transesophageal echocardiography revealed tricuspid insufficiency. Right atriotomy was performed, and a detailed examination revealed that the tricuspid valve septal leaflet was split in two. There was also an atrial septal injury that created a connection with the left atrium; these injuries were not detected from the right ventricular wound. After repair, weaning from cardiopulmonary bypass with mild tricuspid insufficiency was achieved, and she recovered uneventfully. This case emphasized the importance of thoroughly investigating intracardiac injury and transesophageal echocardiography.

Intraoperative Adrenal Insufficiency in a Patient with Prader-Willi Syndrome

OpenAIRE

Barbara, David W.; Hannon, James D.; Hartman, William R.

2012-01-01

Prader-Willi syndrome (PW) is a rare genetic disorder with multi-organ system involvement. These patients present many perioperative challenges including sleep-related breathing disorders, morbid obesity, thick salivary secretions, mental retardation, and difficult intravenous access. PW has been suggested to be associated with central adrenal insufficiency. We report a novel case of persistent severe hypotension from previously undiagnosed and asymptomatic adrenal insufficiency in a pediatri...

Vitamin D Insufficiency among Free-Living Healthy Young Adults

OpenAIRE

Tangpricha, Vin; Pearce, Elizabeth N.; Chen, Tai C.; Holick, Michael F.

2002-01-01

Long-term vitamin D insufficiency can cause secondary hyperparathyroidism and osteomalacia (1). In addition, there is increasing evidence that vitamin D may protect against common cancers, such as cancer of the colon (2–4), prostate (5), and breast (6). Young adults aged 17 to 35 years drink inadequate amounts of milk (7) and are concerned about exposure to the sun because of the fear of developing skin cancer (8,9), which increases the risk of vitamin D insufficiency (10). We sought to exami...

Statistics of Data Fitting: Flaws and Fixes of Polynomial Analysis of Channeled Spectra

Science.gov (United States)

Karstens, William; Smith, David

2013-03-01

Starting from general statistical principles, we have critically examined Baumeister's procedure* for determining the refractive index of thin films from channeled spectra. Briefly, the method assumes that the index and interference fringe order may be approximated by polynomials quadratic and cubic in photon energy, respectively. The coefficients of the polynomials are related by differentiation, which is equivalent to comparing energy differences between fringes. However, we find that when the fringe order is calculated from the published IR index for silicon* and then analyzed with Baumeister's procedure, the results do not reproduce the original index. This problem has been traced to 1. Use of unphysical powers in the polynomials (e.g., time-reversal invariance requires that the index is an even function of photon energy), and 2. Use of insufficient terms of the correct parity. Exclusion of unphysical terms and addition of quartic and quintic terms to the index and order polynomials yields significantly better fits with fewer parameters. This represents a specific example of using statistics to determine if the assumed fitting model adequately captures the physics contained in experimental data. The use of analysis of variance (ANOVA) and the Durbin-Watson statistic to test criteria for the validity of least-squares fitting will be discussed. *D.F. Edwards and E. Ochoa, Appl. Opt. 19, 4130 (1980). Supported in part by the US Department of Energy, Office of Nuclear Physics under contract DE-AC02-06CH11357.

A Meta-Meta-Analysis: Empirical Review of Statistical Power, Type I Error Rates, Effect Sizes, and Model Selection of Meta-Analyses Published in Psychology

Science.gov (United States)

Cafri, Guy; Kromrey, Jeffrey D.; Brannick, Michael T.

2010-01-01

This article uses meta-analyses published in "Psychological Bulletin" from 1995 to 2005 to describe meta-analyses in psychology, including examination of statistical power, Type I errors resulting from multiple comparisons, and model choice. Retrospective power estimates indicated that univariate categorical and continuous moderators, individual…

Bedtime procrastination: A self-regulation perspective on sleep insufficiency in the general population.

Science.gov (United States)

Kroese, Floor M; Evers, Catharine; Adriaanse, Marieke A; de Ridder, Denise T D

2016-05-01

Getting insufficient sleep has serious consequences in terms of mental and physical health. The current study is the first to approach insufficient sleep from a self-regulation perspective by investigating the phenomenon of bedtime procrastination: going to bed later than intended, without having external reasons for doing so. Data from a representative sample of Dutch adults (N = 2431) revealed that a large proportion of the general population experiences getting insufficient sleep and regularly goes to bed later than they would like to. Most importantly, a relationship between self-regulation and experienced insufficient sleep was found, which was mediated by bedtime procrastination. © The Author(s) 2014.

Improving the Crossing-SIBTEST Statistic for Detecting Non-uniform DIF.

Science.gov (United States)

Chalmers, R Philip

2018-06-01

This paper demonstrates that, after applying a simple modification to Li and Stout's (Psychometrika 61(4):647-677, 1996) CSIBTEST statistic, an improved variant of the statistic could be realized. It is shown that this modified version of CSIBTEST has a more direct association with the SIBTEST statistic presented by Shealy and Stout (Psychometrika 58(2):159-194, 1993). In particular, the asymptotic sampling distributions and general interpretation of the effect size estimates are the same for SIBTEST and the new CSIBTEST. Given the more natural connection to SIBTEST, it is shown that Li and Stout's hypothesis testing approach is insufficient for CSIBTEST; thus, an improved hypothesis testing procedure is required. Based on the presented arguments, a new chi-squared-based hypothesis testing approach is proposed for the modified CSIBTEST statistic. Positive results from a modest Monte Carlo simulation study strongly suggest the original CSIBTEST procedure and randomization hypothesis testing approach should be replaced by the modified statistic and hypothesis testing method.

Changes in stimulus and response AC/A ratio with vision therapy in Convergence Insufficiency.

Science.gov (United States)

Singh, Neeraj Kumar; Mani, Revathy; Hussaindeen, Jameel Rizwana

To evaluate the changes in the stimulus and response Accommodative Convergence to Accommodation (AC/A) ratio following vision therapy (VT) in Convergence Insufficiency (CI). Stimulus and response AC/A ratio were measured on twenty five CI participants, pre and post 10 sessions of VT. Stimulus AC/A ratio was measured using the gradient method and response AC/A ratio was calculated using modified Thorington technique with accommodative responses measured using WAM-5500 open-field autorefractor. The gradient stimulus and response AC/A cross-link ratios were compared with thirty age matched controls. Mean age of the CI and control participants were 23.3±5.2 years and 22.7±4.2 years, respectively. The mean stimulus and response AC/A ratio for CI pre therapy was 2.2±0.72 and 6.3±2.0 PD/D that changed to 4.2±0.9 and 8.28±3.31 PD/D respectively post vision therapy and these changes were statistically significant (paired t-test; paccommodation parameters in subjects with convergence insufficiency. This represents the plasticity of the AC/A crosslink ratios that could be achieved with vision therapy in CI. Copyright © 2016 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

Evaluation the short term effects on serum creatinine concentration in patients with normal renal function, mild and moderate renal insufficiency after intravenous injection of gadopentetate dimeglumine

International Nuclear Information System (INIS)

Luo Jian; Liu Jing; Wang Xiaoying; Yang Xuedong; Jiang Xuexiang

2010-01-01

Objective: To explore the effects of gadopentetate dimeglumine injection on renal function. Methods: The study included 623 consecutive patients. Their serum creatinine concentrations before and within 3 days after injection of gadopentetate dimeglumine were analyzed. Their eGFR (estimated glomerular filtration rate) were calculated. Patients were divided into two groups according to their injection dose: group received single dose and group received double dose. Patients in each group were subdivided into three subgroups according to their eGFR: subgroup of normal renal function, subgroup of mild renal insufficiency and subgroup of moderate renal insufficiency. Paried sample t test and group design paired sample Rank Sum test were used for statistical analysis. Results: There was no adverse reaction or occurrence of acute renal insufficiency. The mean level of serum creatinine dropped from (74.0± 17.2) μmol/L to (71.5±19.0) μmol/L (t=5.39, P 0.05) in subgroup of mild renal insufficiency under group received double dose and increased from (118.3±15.3) μmol/L to (135.7±8.5) μmol/L (t=2.02, P<0.05) in subgroup of moderate renal insufficiency under group received double dose, the mean level of serum creatinine dropped in all other subgroups. Conclusions: Single dose gadopentetate dimeglumine is safe for patients with normal renal function and mild, moderate renal insufficiency in short term, but patients with abnormal renal function should be followed up after double dose injection. (authors)

AMH as Predictor of Premature Ovarian Insufficiency

DEFF Research Database (Denmark)

Lunding, Stine Aa; Aksglæde, Lise; Anderson, Richard A

2015-01-01

CONTEXT: The majority of Turner syndrome (TS) patients suffer from accelerated loss of primordial follicles. Low circulating levels of anti-Müllerian hormone (AMH) may predict the lack of spontaneous puberty in prepubertal girls and imminent premature ovarian insufficiency (POI) in TS women...

Electric power annual, 1991

International Nuclear Information System (INIS)

1993-01-01

The Electric Power Annual is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels; Energy Information Administration (EIA); US Department of Energy. The 1991 edition has been enhanced to include statistics on electric utility demand-side management and nonutility supply. ''The US Electric Power Industry at a Glance'' section presents a profile of the electric power industry ownership and performance, and a review of key statistics for the year. Subsequent sections present data on generating capability, including proposed capability additions; net generation; fossil-fuel statistics; electricity sales, revenue, and average revenue per kilowatthour sold; financial statistics; environmental statistics; electric power transactions; demand-side management; and nonutility power producers. In addition, the appendices provide supplemental data on major disturbances and unusual occurrences in US electricity power systems. Each section contains related text and tables and refers the reader to the appropriate publication that contains more detailed data on the subject matter. Monetary values in this publication are expressed in nominal terms

Impact of placental insufficiency on fetal skeletal muscle growth

Science.gov (United States)

Hay, William W.

2016-01-01

Intrauterine growth restriction (IUGR) caused by placental insufficiency is one of the most common and complex problems in perinatology, with no known cure. In pregnancies affected by placental insufficiency, a poorly functioning placenta restricts nutrient supply to the fetus and prevents normal fetal growth. Among other significant deficits in organ development, the IUGR fetus characteristically has less lean body and skeletal muscle mass than their appropriately-grown counterparts. Reduced skeletal muscle growth is not fully compensated after birth, as individuals who were born small for gestational age (SGA) from IUGR have persistent reductions in muscle mass and strength into adulthood. The consequences of restricted muscle growth and accelerated postnatal “catch-up” growth in the form of adiposity may contribute to the increased later life risk for visceral adiposity, peripheral insulin resistance, diabetes, and cardiovascular disease in individuals who were formerly IUGR. This review will discuss how an insufficient placenta results in impaired fetal skeletal muscle growth and how lifelong reductions in muscle mass might contribute to increased metabolic disease risk in this vulnerable population. PMID:26994511

Prospective Power Calculations for the Four Lab Study of A Multigenerational Reproductive/Developmental Toxicity Rodent Bioassay Using A Complex Mixture of Disinfection By-Products in the Low-Response Region

Directory of Open Access Journals (Sweden)

Jane Ellen Simmons

2011-10-01

Full Text Available In complex mixture toxicology, there is growing emphasis on testing environmentally representative doses that improve the relevance of results for health risk assessment, but are typically much lower than those used in traditional toxicology studies. Traditional experimental designs with typical sample sizes may have insufficient statistical power to detect effects caused by environmentally relevant doses. Proper study design, with adequate statistical power, is critical to ensuring that experimental results are useful for environmental health risk assessment. Studies with environmentally realistic complex mixtures have practical constraints on sample concentration factor and sample volume as well as the number of animals that can be accommodated. This article describes methodology for calculation of statistical power for non-independent observations for a multigenerational rodent reproductive/developmental bioassay. The use of the methodology is illustrated using the U.S. EPA’s Four Lab study in which rodents were exposed to chlorinated water concentrates containing complex mixtures of drinking water disinfection by-products. Possible experimental designs included two single-block designs and a two-block design. Considering the possible study designs and constraints, a design of two blocks of 100 females with a 40:60 ratio of control:treated animals and a significance level of 0.05 yielded maximum prospective power (~90% to detect pup weight decreases, while providing the most power to detect increased prenatal loss.

Prospective Power Calculations for the Four Lab Study of A Multigenerational Reproductive/Developmental Toxicity Rodent Bioassay Using A Complex Mixture of Disinfection By-Products in the Low-Response Region

Science.gov (United States)

Dingus, Cheryl A.; Teuschler, Linda K.; Rice, Glenn E.; Simmons, Jane Ellen; Narotsky, Michael G.

2011-01-01

In complex mixture toxicology, there is growing emphasis on testing environmentally representative doses that improve the relevance of results for health risk assessment, but are typically much lower than those used in traditional toxicology studies. Traditional experimental designs with typical sample sizes may have insufficient statistical power to detect effects caused by environmentally relevant doses. Proper study design, with adequate statistical power, is critical to ensuring that experimental results are useful for environmental health risk assessment. Studies with environmentally realistic complex mixtures have practical constraints on sample concentration factor and sample volume as well as the number of animals that can be accommodated. This article describes methodology for calculation of statistical power for non-independent observations for a multigenerational rodent reproductive/developmental bioassay. The use of the methodology is illustrated using the U.S. EPA’s Four Lab study in which rodents were exposed to chlorinated water concentrates containing complex mixtures of drinking water disinfection by-products. Possible experimental designs included two single-block designs and a two-block design. Considering the possible study designs and constraints, a design of two blocks of 100 females with a 40:60 ratio of control:treated animals and a significance level of 0.05 yielded maximum prospective power (~90%) to detect pup weight decreases, while providing the most power to detect increased prenatal loss. PMID:22073030

Wind energy statistics 2012; Vindkraftsstatistik 2012

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-04-15

The publication 'Wind Energy Statistics' is an annual publication. Since 2010, the reported statistics of installed power, number of plants and regional distribution, even semi-annually, and in tabular form on the Agency's website. The publication is produced in a new way this year, which will result in some data differ from previous publications. Due to the certificate system there is basically full statistics on wind energy in this publication which are presented in different styles. Here we present the regional distribution, ie. how the number of turbines and installed capacity is allocated to counties and municipalities. The electricity produced divided by county, where for reasons of confidentiality possible, are also reported. The wind power is becoming increasingly important in the Swedish energy system which provides an increased demand for statistics and other divisions than that presented in the official statistics. Therefore, this publication, which are not official statistics, has been developed.

Statistical core design

International Nuclear Information System (INIS)

Oelkers, E.; Heller, A.S.; Farnsworth, D.A.; Kearfott, K.J.

1978-01-01

The report describes the statistical analysis of DNBR thermal-hydraulic margin of a 3800 MWt, 205-FA core under design overpower conditions. The analysis used LYNX-generated data at predetermined values of the input variables whose uncertainties were to be statistically combined. LYNX data were used to construct an efficient response surface model in the region of interest; the statistical analysis was accomplished through the evaluation of core reliability; utilizing propagation of the uncertainty distributions of the inputs. The response surface model was implemented in both the analytical error propagation and Monte Carlo Techniques. The basic structural units relating to the acceptance criteria are fuel pins. Therefore, the statistical population of pins with minimum DNBR values smaller than specified values is determined. The specified values are designated relative to the most probable and maximum design DNBR values on the power limiting pin used in present design analysis, so that gains over the present design criteria could be assessed for specified probabilistic acceptance criteria. The results are equivalent to gains ranging from 1.2 to 4.8 percent of rated power dependent on the acceptance criterion. The corresponding acceptance criteria range from 95 percent confidence that no pin will be in DNB to 99.9 percent of the pins, which are expected to avoid DNB

Hybrid power markets in Africa: Generation planning, procurement and contracting challenges

International Nuclear Information System (INIS)

Malgas, Isaac; Eberhard, Anton

2011-01-01

African power sectors are generally characterised by insufficient generation capacity. Reforms to address poor performances in the 1990s followed a prescribed evolution towards power markets that would allow wholesale competition amongst generators and so lead towards efficiency improvements. Despite reforms being embarked, competitive power markets have not been established in Africa; rather, the result has been the emergence of hybrid markets where state-owned generators and IPPs operate devoid of competition; and although IPPs have emerged in a number of African power sectors, many countries still do not have sufficient generation to meet their electricity demands. This paper investigates the development of private generation power projects in Africa by analysing data collected from both primary and secondary sources in four case studies of power sectors in Ghana, Cote d'Ivoire, Morocco and Tunisia. It identifies how planning and procurement challenges have lead to difficulties in adding sufficient generation capacity in a timely manner, exacerbating the problem of insufficient generation capacity in Africa. It provides suggestions as to how these frameworks could respond more effectively to the capacity challenges faced by hybrid electricity generation markets, and how broader power sector reforms should be guided to reflect the challenges of hybrid markets better. - Research highlights: → The standard model of power sector reform should no longer be used as a progress measure of power sector development in Africa and many other developing countries. → The hybrid market should in itself be recognised as an established 'model' of power sectors in Africa and many developing countries. → Planning, procurement and contracting arrangements should be shaped specifically for hybrid markets in order to address the problem of insufficient generation capacity in developing countries.

Early intervention and management of adrenal insufficiency in children.

LENUS (Irish Health Repository)

Moloney, Sinéad

2012-09-01

The endocrine disorder adrenal insufficiency includes inadequate production of the steroid hormone cortisol. This results in poor physiological responses to illness, trauma or other stressors and risk of adrenal crisis. Management is based on administration of hydrocortisone. It is important to avoid under- or over-treatment and increase the dosage during times of physiological stress. To reduce morbidity, hospital admissions and mortality, the education and empowerment of parents and carers, and prompt intervention when necessary are essential. A steroid therapy card for adrenal insufficiency containing personal information on a patient\\'s condition was developed for use by families and their specialist centres.

MR appearance of parasymphyseal insufficiency fractures of the os pubis

Energy Technology Data Exchange (ETDEWEB)

Hosono, Mariko; Fujimoto, Ryota; Konishi, Junji [Department of Nuclear Medicine, Faculty of Medicine, Kyoto University, 54 Shogoin-kawahara-cho, Sakyo-ku, Kyoto (Japan); Kobayashi, Hisataka [Nulcear Medicine Department, National Institutes of Health, Building 10, Room 1C-401, Bethesda, MD 20892 (United States); Tsutsui, Kazushige [Department of Radiology, Japanese Red Cross Society Wakayama Medical Center, Wakayama (Japan); Kotoura, Yoshihiko [Department of Orthopaedic Surgery, Nagahama City Hospital, Nagahama, Shiga (Japan); Tsuboyama, Tadao; Nakamura, Takashi [Department of Orthopaedic Surgery, Faculty of Medicine, Kyoto University, Kyoto (Japan); Hayashi, Hikaru [Department of Orthopaedic Surgery, Japanese Red Cross Society Wakayama Medical Center, Wakayama (Japan)

1997-09-01

Objective. To clarify the MRI features of parasymphyseal insufficiency fractures of the os pubis. Design and patients. MRI was performed in four postmenopausal women with parasymphyseal insufficiency fractures. The diagnosis was confirmed with plain films in every patient. T1-weighted and T2-weighted images were obtained in four patients using a 1.5-T unit. Postcontrast T1-weighted imaging was also done in three patients. Results and conclusions. MRI of pubic parasymphyseal insufficiency fracture characteristically demonstrates a hyperintense mass lesion with a hypointense rim on T2-weighted imaging, showing peripheral and septal enhancement after contrast administration. It is important to have this entity in mind in patients with osteoporosis, especially in patients with a history of pelvic irradiation for malignant disease, so as not to misinterpret it as a chondroid tumor or bone metastasis. (orig.). With 2 figs., 2 tabs.

The statistical analysis of anisotropies

International Nuclear Information System (INIS)

Webster, A.

1977-01-01

One of the many uses to which a radio survey may be put is an analysis of the distribution of the radio sources on the celestial sphere to find out whether they are bunched into clusters or lie in preferred regions of space. There are many methods of testing for clustering in point processes and since they are not all equally good this contribution is presented as a brief guide to what seems to be the best of them. The radio sources certainly do not show very strong clusering and may well be entirely unclustered so if a statistical method is to be useful it must be both powerful and flexible. A statistic is powerful in this context if it can efficiently distinguish a weakly clustered distribution of sources from an unclustered one, and it is flexible if it can be applied in a way which avoids mistaking defects in the survey for true peculiarities in the distribution of sources. The paper divides clustering statistics into two classes: number density statistics and log N/log S statistics. (Auth.)

29 CFR 541.2 - Job titles insufficient.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Job titles insufficient. 541.2 Section 541.2 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS DEFINING AND DELIMITING THE EXEMPTIONS FOR EXECUTIVE, ADMINISTRATIVE, PROFESSIONAL, COMPUTER AND OUTSIDE SALES EMPLOYEES...

Design of durability test protocol for vehicular fuel cell systems operated in power-follow mode based on statistical results of on-road data

Science.gov (United States)

Xu, Liangfei; Reimer, Uwe; Li, Jianqiu; Huang, Haiyan; Hu, Zunyan; Jiang, Hongliang; Janßen, Holger; Ouyang, Minggao; Lehnert, Werner

2018-02-01

City buses using polymer electrolyte membrane (PEM) fuel cells are considered to be the most likely fuel cell vehicles to be commercialized in China. The technical specifications of the fuel cell systems (FCSs) these buses are equipped with will differ based on the powertrain configurations and vehicle control strategies, but can generally be classified into the power-follow and soft-run modes. Each mode imposes different levels of electrochemical stress on the fuel cells. Evaluating the aging behavior of fuel cell stacks under the conditions encountered in fuel cell buses requires new durability test protocols based on statistical results obtained during actual driving tests. In this study, we propose a systematic design method for fuel cell durability test protocols that correspond to the power-follow mode based on three parameters for different fuel cell load ranges. The powertrain configurations and control strategy are described herein, followed by a presentation of the statistical data for the duty cycles of FCSs in one city bus in the demonstration project. Assessment protocols are presented based on the statistical results using mathematical optimization methods, and are compared to existing protocols with respect to common factors, such as time at open circuit voltage and root-mean-square power.

Adrenal Insufficiency as a Cause of Acute Liver Failure: A Case Report

Directory of Open Access Journals (Sweden)

Jamshid Vafaeimanesh

2013-01-01

Full Text Available Introduction. Many diseases and conditions can contribute to elevated liver enzymes. Common causes include viral and autoimmune hepatitis, fatty liver, and bile duct diseases, but, in uncommon cases like liver involvement in endocrine disorders, liver failure is also seen. Adrenal insufficiency is the rarest endocrine disorder complicating the liver. In the previously reported cases of adrenal insufficiency, mild liver enzymes elevation was seen but we report a case with severe elevated liver enzymes and liver failure due to adrenal insufficiency. Based on our knowledge, this is the first report in this field. Case Report. A 39-year-old woman was referred to emergency ward due to drowsiness and severe fatigue. Her laboratory tests revealed prothrombin time: 21 sec, alanine aminotransferase (ALT: 2339 IU/L, aspartate aminotransferase (AST: 2002 IU/L, and ALP: 90 IU/L. No common cause of liver involvement was discovered, and eventually, with diagnosis of adrenal insufficiency and corticosteroid therapy, liver enzymes and function became normal. Finally, the patient was discharged with good general condition. Conclusion. With this report, we emphasize adrenal insufficiency (primary or secondary as a reason of liver involvement in unexplainable cases and recommend that any increase in the liver enzymes, even liver failure, in these patients should be observed.

Wind power deployment outcomes: How can we account for the differences?

NARCIS (Netherlands)

Toke, D.; Breukers, S.; Wolsink, M.

2008-01-01

This paper aims to understand different outcomes of implementation of wind power deployment programmes. Geographical variables such as quantity of wind resources are in themselves insufficient to explain patterns of implementation of wind power. To enhance the review of the factors affecting wind

Electric power annual 1992

Energy Technology Data Exchange (ETDEWEB)

1994-01-06

The Electric Power Annual presents a summary of electric utility statistics at national, regional and State levels. The objective of the publication is to provide industry decisionmakers, government policymakers, analysts and the general public with historical data that may be used in understanding US electricity markets. The Electric Power Annual is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels; Energy Information Administration (EIA); US Department of Energy. ``The US Electric Power Industry at a Glance`` section presents a profile of the electric power industry ownership and performance, and a review of key statistics for the year. Subsequent sections present data on generating capability, including proposed capability additions; net generation; fossil-fuel statistics; retail sales; revenue; financial statistics; environmental statistics; electric power transactions; demand-side management; and nonutility power producers. In addition, the appendices provide supplemental data on major disturbances and unusual occurrences in US electricity power systems. Each section contains related text and tables and refers the reader to the appropriate publication that contains more detailed data on the subject matter. Monetary values in this publication are expressed in nominal terms.

Radiological features of superomedial iliac insufficiency fractures: a possible mimicker of metastatic disease

International Nuclear Information System (INIS)

Donovan, Andrea; Schweitzer, Mark E.; Rafii, Mahvash; Lax, Allison

2009-01-01

Pelvic insufficiency fractures are common in elderly patients. Because both osteoporosis and metastatic disease occur in similar patient populations, insufficiency fractures may be mistaken for metastatic foci. Although the ilium is not an uncommon location for metastases, insufficiency fractures rarely involve the ilium. The radiological features of insufficiency fractures adjacent to the sacroiliac joint (superomedial ilium) have not been well described. We describe the computed tomography (CT), magnetic resonance (MR), and positron emission tomography (PET) imaging findings of these rare fractures. Six patients (five female, one male; mean age 66 years, age range 47-83 years) with iliac insufficiency fractures adjacent to the sacroiliac joint were identified following retrospective review of a clinical database. Imaging studies, including CT (n = 4), MR (n = 3), and PET (n = 2) were reviewed by two radiologists. Tissue biopsy result was available in one patient. CT demonstrated subtle fracture lucency (n = 2) or linear sclerosis (n = 3) adjacent to the sacroiliac joint; MR marrow changes adjacent to the sacroiliac joint demonstrated a low T1, high T2 signal intensity line (n = 2), or a low T1 and low T2 signal intensity line (n = 1). Fractures were fluorodeoxyglucose avid (n = 2) with average SUV max 2.2. Iliac fractures were bilateral in three patients; additional pelvic insufficiency fractures were present in one patient. In one patient, CT-guided biopsy showed no evidence of malignancy. Recognition of the radiological characteristics of iliac insufficiency fractures is important in order to distinguish them from malignancy. The presence of additional pelvic fractures in characteristic locations in the setting of osteoporosis may help to confirm the diagnosis. (orig.)

Radiological features of superomedial iliac insufficiency fractures: a possible mimicker of metastatic disease

Energy Technology Data Exchange (ETDEWEB)

Donovan, Andrea; Schweitzer, Mark E. [NYU Hospital for Joint Diseases, New York, NY (United States); Rafii, Mahvash [New York, NY (United States); Lax, Allison [Georgetown University Hospital, Washington, DC (United States)

2009-01-15

Pelvic insufficiency fractures are common in elderly patients. Because both osteoporosis and metastatic disease occur in similar patient populations, insufficiency fractures may be mistaken for metastatic foci. Although the ilium is not an uncommon location for metastases, insufficiency fractures rarely involve the ilium. The radiological features of insufficiency fractures adjacent to the sacroiliac joint (superomedial ilium) have not been well described. We describe the computed tomography (CT), magnetic resonance (MR), and positron emission tomography (PET) imaging findings of these rare fractures. Six patients (five female, one male; mean age 66 years, age range 47-83 years) with iliac insufficiency fractures adjacent to the sacroiliac joint were identified following retrospective review of a clinical database. Imaging studies, including CT (n = 4), MR (n = 3), and PET (n = 2) were reviewed by two radiologists. Tissue biopsy result was available in one patient. CT demonstrated subtle fracture lucency (n = 2) or linear sclerosis (n = 3) adjacent to the sacroiliac joint; MR marrow changes adjacent to the sacroiliac joint demonstrated a low T1, high T2 signal intensity line (n = 2), or a low T1 and low T2 signal intensity line (n = 1). Fractures were fluorodeoxyglucose avid (n = 2) with average SUV{sub max} 2.2. Iliac fractures were bilateral in three patients; additional pelvic insufficiency fractures were present in one patient. In one patient, CT-guided biopsy showed no evidence of malignancy. Recognition of the radiological characteristics of iliac insufficiency fractures is important in order to distinguish them from malignancy. The presence of additional pelvic fractures in characteristic locations in the setting of osteoporosis may help to confirm the diagnosis. (orig.)

Vertebrobasilar insufficiency and possible relationships with arterial changes

International Nuclear Information System (INIS)

Tonagel, J.

1982-01-01

The study described was carried out in order to clarify the question as to whether overt neurological disorders in the vertebrobasilar region are connected with arterial changes that may be ascertained by means of X-ray examinations. For this purpose, the clinical and angiographic data of 54 patients showing vertebrobasilar insufficiency were subjected to detailed analysis. In all cases, an angiographic examination of the branchial artery had been so performed as to permit visualisation of the vertebrobasilar territory. The macroscopic changes revealed by angiography were evaluated on the basis of the severity of the clinical symptoms and the age of the patient. It was found that the frequency of visualised changes in the arterial system that could be matched with neurological symptoms only just attained statistical significance in women of advanced age, while the findings revealed in men were not consistent with the clinical signs. The manifestation of those changes largely depends on the individual degree of collateral blood supply. This, a direct relationship between the angiographic findings and the clinical symptoms is only likely to be observed in cases where the development of collaterals was prevented due to the site of vascular obstruction or where the incident happened just prior to the examination. A typical example here is recent thrombosis of the basilar artery. (TRV) [de

A d-statistic for single-case designs that is equivalent to the usual between-groups d-statistic.

Science.gov (United States)

Shadish, William R; Hedges, Larry V; Pustejovsky, James E; Boyajian, Jonathan G; Sullivan, Kristynn J; Andrade, Alma; Barrientos, Jeannette L

2014-01-01

We describe a standardised mean difference statistic (d) for single-case designs that is equivalent to the usual d in between-groups experiments. We show how it can be used to summarise treatment effects over cases within a study, to do power analyses in planning new studies and grant proposals, and to meta-analyse effects across studies of the same question. We discuss limitations of this d-statistic, and possible remedies to them. Even so, this d-statistic is better founded statistically than other effect size measures for single-case design, and unlike many general linear model approaches such as multilevel modelling or generalised additive models, it produces a standardised effect size that can be integrated over studies with different outcome measures. SPSS macros for both effect size computation and power analysis are available.

Endocrine and exocrine pancreatic insufficiency after acute pancreatitis: long-term follow-up study.

Science.gov (United States)

Tu, Jianfeng; Zhang, Jingzhu; Ke, Lu; Yang, Yue; Yang, Qi; Lu, Guotao; Li, Baiqiang; Tong, Zhihui; Li, Weiqin; Li, Jieshou

2017-10-27

Patients could develop endocrine and exocrine pancreatic insufficiency after acute pancreatitis (AP), but the morbidity, risk factors and outcome remain unclear. The aim of the present study was to evaluate the incidence of endocrine and exocrine pancreatic insufficiency after AP and the risk factors of endocrine pancreatic insufficiency through a long-term follow-up investigation. Follow-up assessment of the endocrine and exocrine function was conducted for the discharged patients with AP episodes. Oral Glucose Tolerance Test (OGTT) and faecal elastase-1(FE-1) test were used as primary parameters. Fasting blood-glucose (FBG), fasting insulin (FINS), glycosylated hemoglobin HBA1c, 2-h postprandial blood glucose (2hPG), Homa beta cell function index (HOMA-β), homeostasis model assessment of insulin resistance (HOMA-IR) and FE-1 were collected. Abdominal contrast-enhanced computed tomography (CECT) was performed to investigate the pancreatic morphology and the other related data during hospitalization was also collected. One hundred thirteen patients were included in this study and 34 of whom (30.1%) developed diabetes mellitus (DM), 33 (29.2%) suffered impaired glucose tolerance (IGT). Moreover, 33 patients (29.2%) developed mild to moderate exocrine pancreatic insufficiency with 100μg/gpancreatic insufficiency with FE-1pancreatic necrosis was significant higher than that in the non-pancreatic necrosis group (X 2  = 13.442,P = 0.001). The multiple logistic regression analysis showed that extent of pancreatic necrosisendocrine pancreatic insufficiency. HOMA-IR (P = 0.002, OR = 6.626), Wall-off necrosis (WON) (P = 0.013, OR = 184.772) were the risk factors. The integrated morbidity of DM and IGT after AP was 59.25%, which was higher than exocrine pancreatic insufficiency. 6.2% and 29.2% of patients developed severe and mild to moderate exocrine pancreatic insufficiency, respectively. The extent of pancreatic necrosis>50%, WON and insulin resistance were

Statistical inquiry on the reliability of emergency diesel stations in German nuclear power plants

International Nuclear Information System (INIS)

1983-01-01

This statistic inquiry is based on 692 occurrances in 40 diesel stations of 10 German nuclear power plants. Various parameters influencing the failure behaviour of diesel stations were investigated on only significant plant-specific influences and the impact of diesel station circuitry on failure behaviour were established. According to the results of this inquiry, running time, start-up number and increasing operational experience do not apparently influence the failure behaviour of diesel stations. The expected failure probability of diesel stations varies with the different nuclear power plants. Taking into account both start-up and operational failures, (with monthly inspections and running times of up to 2 h), this value is in the range of 1.6 x 10 -2 to 1.7 x 10 -3 per application. Considering failure data of all diesel stations, the failure probability (start-up and operational failures) is 8.1 x 10 -3 per application. On account of the two common-mode failures registered, a common-mode failure probability of 10 -3 was established. The inquiry also showed that non-availability of diesel stations is essentially determined by maintenance intervals. (orig.) [de

Prognostic value of relative adrenal insufficiency after out-of-hospital cardiac arrest.

Science.gov (United States)

Pene, Frédéric; Hyvernat, Hervé; Mallet, Vincent; Cariou, Alain; Carli, Pierre; Spaulding, Christian; Dugue, Marie-Annick; Mira, Jean-Paul

2005-05-01

To assess the prevalence of relative adrenal insufficiency in patients successfully resuscitated after cardiac arrest, and its prognostic role in post-resuscitation disease. A prospective observational single-center study in a medical intensive care unit. 64 patients hospitalised in the intensive care unit after successful resuscitation for out-of-hospital cardiac arrest. A corticotropin-stimulation test was performed between 12 and 24 h following admission: serum cortisol level was measured before and 60 min after administration of tetracosactide 250 microg. Patients with an incremental response less than 9 microg/dl were considered to have relative adrenal insufficiency (non-responders). Variables were expressed as medians and interquartile ranges. 33 patients (52%) had relative adrenal insufficiency. Baseline cortisol level was higher in non-responders than in responders (41 [27.2-55.5] vs. 22.8 [15.7-35.1] microg/dl respectively, P=0.001). A long interval before initiation of cardiopulmonary resuscitation was associated with relative adrenal insufficiency (5 [3-10] vs. 3 [3-5] min, P=0.03). Of the 38 patients with post-resuscitation shock, 13 died of irreversible multiorgan failure. The presence of relative adrenal insufficiency was identified as a poor prognostic factor of shock-related mortality (log-rank P=0.02). A trend towards higher mortality in non-responders was identified in a multivariate logistic regression analysis (odds ratio 6.77, CI 95% 0.94-48.99, P=0.058). Relative adrenal insufficiency occurs frequently after successful resuscitation of out-of-hospital cardiac arrest, and appears to be associated with a poor prognosis in cases of post-resuscitation shock. The role of corticosteroid supplementation should be evaluated in this setting.

Cervical cerclage placement decreases local levels of proinflammatory cytokines in patients with cervical insufficiency.

Science.gov (United States)

Monsanto, Stephany P; Daher, Silvia; Ono, Erika; Pendeloski, Karen Priscilla Tezotto; Trainá, Évelyn; Mattar, Rosiane; Tayade, Chandrakant

2017-10-01

Cervical insufficiency is characterized by premature, progressive dilation and shortening of the cervix during pregnancy. If left unattended, this can lead to the prolapse and rupture of the amniotic membrane, which usually results in midtrimester pregnancy loss or preterm birth. Previous studies have shown that proinflammatory cytokines such as interleukin-1β, interleukin-6, interleukin-8, and tumor necrosis factor alpha are up-regulated in normal parturition but are also associated with preterm birth. Studies evaluating such markers in patients with cervical insufficiency have evaluated only their diagnostic potential. Even fewer studies have studied them within the context of cerclage surgery. The objective of the study was to evaluate the impact of local and systemic inflammatory markers on the pathogenesis of cervical insufficiency and the effect of cerclage surgery on the local immune microenvironment of women with cervical insufficiency. We recruited 28 pregnant women (12-20 weeks' gestation) diagnosed with insufficiency and referred for cerclage surgery and 19 gestational age-matched normal pregnant women as controls. Serum and cervicovaginal fluid samples were collected before and after cerclage surgery and during a routine checkup for normal women and analyzed using a targeted 13-plex proinflammatory cytokine assay. Before surgery, patients with cervical insufficiency had higher levels of interleukin-1β, interleukin-6, interleukin-12, monocyte chemoattractant protein-1 and tumor necrosis factor alpha in cervicovaginal fluid compared to controls, but after surgery, these differences disappeared. No differences were found in serum of insufficiency versus control women. In patients with insufficiency, the levels of interleukin-1β, interleukin-6, interleukin-8, monocyte chemoattractant protein-1, and interferon gamma in cervicovaginal fluid declined significantly after cerclage compared with before intervention, but these changes were not detected in serum

[Membranous nephropathy associated to autoimmune thyroiditis, chronic pancreatitis and suprarrenal insufficiency].

Science.gov (United States)

Merino, J L; Fernández Lucas, M; Teruel, J L; Valer, P; Moreira, V; Arambarri, M; Ortuño, J

2004-01-01

A 33 year old female was admitted to the hospital to study aedema and bocio, A nephrotic syndrome was diagnosed and the renal biopsy demonstrated membranous glomerulonephritis, stage II. She was also diagnosed of Hashimoto's autoinmmune thyroiditis: TSH (41.5 uUl/ml), T4 (0.07 ng/dl), antithyroglobuline (1/2560) and antimicrosome (1/6400). Four year latter she was diagnosed of autoinmmune pancreatitis, without evidence of diabetes mellitus or exocrine pancreatic insufficiency. Eight years latter she was diagnosed of primary autoimmune suprarrenal insufficiency: basal cortisol: 2.7 mcg/dl, post ACTH estimulated cortisol: 5.6 mcg/dl, antinuclear antibody (1/160) and antiparietal (1/320). We present a pluriglandular autoimmune syndrome with membranous glomerulonephritis, thyroiditis, pancreatitis and suprarrenal insufficiency. To the best of our knowledge this complex syndrome has not been previously described.

Modern applied statistics with s-plus

CERN Document Server

Venables, W N

1997-01-01

S-PLUS is a powerful environment for the statistical and graphical analysis of data. It provides the tools to implement many statistical ideas which have been made possible by the widespread availability of workstations having good graphics and computational capabilities. This book is a guide to using S-PLUS to perform statistical analyses and provides both an introduction to the use of S-PLUS and a course in modern statistical methods. S-PLUS is available for both Windows and UNIX workstations, and both versions are covered in depth. The aim of the book is to show how to use S-PLUS as a powerful and graphical system. Readers are assumed to have a basic grounding in statistics, and so the book is intended for would-be users of S-PLUS, and both students and researchers using statistics. Throughout, the emphasis is on presenting practical problems and full analyses of real data sets. Many of the methods discussed are state-of-the-art approaches to topics such as linear and non-linear regression models, robust a...

Homeostatic responses to amino acid insufficiency

Directory of Open Access Journals (Sweden)

Tracy G. Anthony

2015-09-01

Full Text Available This article provides a brief overview describing how two key signaling pathways, namely the integrated stress response and the mammalian target of rapamycin complex 1, work together to facilitate cellular adaptation to dietary amino acid insufficiency. A deeper understanding of these mechanisms is leading to identification of novel targets which aid in disease treatments, improve stress recovery and increase health span through slowed aging and enhanced metabolic fitness.

Subchondral insufficiency fracture of the knee: a non-traumatic injury with prolonged recovery time

OpenAIRE

Gourlay, Margaret L; Renner, Jordan B; Spang, Jeffrey T; Rubin, Janet E

2015-01-01

Subchondral insufficiency fractures are non-traumatic fractures that occur immediately below the cartilage of a joint. Although low bone density may be present concurrently, it is not the underlying cause of subchondral insufficiency fractures in the majority of patients. Patients with subchondral insufficiency fracture characteristically have unremarkable plain radiographs, while MRI examination may reveal extensive bone marrow oedema and subchondral bone collapse. This article presents a 51...

Where does nuclear power go from here?

International Nuclear Information System (INIS)

1995-01-01

The problem is discussed of the future development of nuclear power in the United Kingdom as well as the situation in the nuclear sector worldwide. Nuclear power will apparently be developed by countries which are concerned about their insufficient fossil fuel resources, countries which have strategic reasons for such a development, and/or countries where public opinion is ignored. Where rich coal, oil or gas resources are available or where ''environmentalists'' rule, nuclear power plants will be constructed scarcely if at all. (Z.S.)

Cognition of and Demand for Education and Teaching in Medical Statistics in China: A Systematic Review and Meta-Analysis

Science.gov (United States)

Li, Gaoming; Yi, Dali; Wu, Xiaojiao; Liu, Xiaoyu; Zhang, Yanqi; Liu, Ling; Yi, Dong

2015-01-01

Background Although a substantial number of studies focus on the teaching and application of medical statistics in China, few studies comprehensively evaluate the recognition of and demand for medical statistics. In addition, the results of these various studies differ and are insufficiently comprehensive and systematic. Objectives This investigation aimed to evaluate the general cognition of and demand for medical statistics by undergraduates, graduates, and medical staff in China. Methods We performed a comprehensive database search related to the cognition of and demand for medical statistics from January 2007 to July 2014 and conducted a meta-analysis of non-controlled studies with sub-group analysis for undergraduates, graduates, and medical staff. Results There are substantial differences with respect to the cognition of theory in medical statistics among undergraduates (73.5%), graduates (60.7%), and medical staff (39.6%). The demand for theory in medical statistics is high among graduates (94.6%), undergraduates (86.1%), and medical staff (88.3%). Regarding specific statistical methods, the cognition of basic statistical methods is higher than of advanced statistical methods. The demand for certain advanced statistical methods, including (but not limited to) multiple analysis of variance (ANOVA), multiple linear regression, and logistic regression, is higher than that for basic statistical methods. The use rates of the Statistical Package for the Social Sciences (SPSS) software and statistical analysis software (SAS) are only 55% and 15%, respectively. Conclusion The overall statistical competence of undergraduates, graduates, and medical staff is insufficient, and their ability to practically apply their statistical knowledge is limited, which constitutes an unsatisfactory state of affairs for medical statistics education. Because the demand for skills in this area is increasing, the need to reform medical statistics education in China has become urgent

Automated Data Collection for Determining Statistical Distributions of Module Power Undergoing Potential-Induced Degradation: Preprint

Energy Technology Data Exchange (ETDEWEB)

Hacke, P.; Spataru, S.

2014-08-01

We propose a method for increasing the frequency of data collection and reducing the time and cost of accelerated lifetime testing of photovoltaic modules undergoing potential-induced degradation (PID). This consists of in-situ measurements of dark current-voltage curves of the modules at elevated stress temperature, their use to determine the maximum power at 25 degrees C standard test conditions (STC), and distribution statistics for determining degradation rates as a function of stress level. The semi-continuous data obtained by this method clearly show degradation curves of the maximum power, including an incubation phase, rates and extent of degradation, precise time to failure, and partial recovery. Stress tests were performed on crystalline silicon modules at 85% relative humidity and 60 degrees C, 72 degrees C, and 85 degrees C. Activation energy for the mean time to failure (1% relative) of 0.85 eV was determined and a mean time to failure of 8,000 h at 25 degrees C and 85% relative humidity is predicted. No clear trend in maximum degradation as a function of stress temperature was observed.

Zinc status in chronic pancreatitis and its relationship with exocrine and endocrine insufficiency.

Science.gov (United States)

Girish, Banavara Narasimhamurthy; Rajesh, Gopalakrishna; Vaidyanathan, Kannan; Balakrishnan, Vallath

2009-11-05

A major role of the pancreas in zinc homeostasis has been suggested. To assess erythrocyte zinc status in chronic pancreatitis and to correlate it with pancreatic exocrine and endocrine insufficiency. One hundred and one patients with chronic pancreatitis (34 alcoholic chronic pancreatitis, 67 tropical chronic pancreatitis) were prospectively studied. Disease characteristics and imaging features were recorded. Erythrocyte zinc was estimated by flame atomic absorption spectrophotometry. Exocrine insufficiency was assessed using polyclonal antibody ELISA for pancreatic stool elastase1. Endocrine insufficiency was assessed by serum glucose levels and insulin requirement. Erythrocyte zinc was significantly lower in chronic pancreatitis patients than in the controls (26.5+/-9.5 microg/g Hb vs. 38.0+/-6.6 microg/g Hb; Ppancreatitis than in alcoholic chronic pancreatitis (25.0+/-10.4 microg/g Hb vs. 29.6+/-6.5 microg/g Hb, P=0.001). In chronic pancreatitis patients who had exocrine insufficiency, erythrocyte zinc positively correlated with stool elastase1 (r=0.587, Ppancreatitis patients, and that zinc deficiency correlates with exocrine and endocrine insufficiency. Further studies may clarify the possible benefits of zinc supplementation in chronic pancreatitis.

A escolha do teste estatístico - um tutorial em forma de apresentação em PowerPoint A PowerPoint®-based guide to assist in choosing the suitable statistical test

Directory of Open Access Journals (Sweden)

David Normando

2010-02-01

Full Text Available A seleção de métodos apropriados para a análise estatística pode parecer complexa, principalmente para estudantes de pós-graduação e pesquisadores no início da carreira científica. Por outro lado, a apresentação em PowerPoint é uma ferramenta comum para estudantes e pesquisadores. Assim, um tutorial de Bioestatística desenvolvido em uma apresentação em PowerPoint poderia estreitar a distância entre ortodontistas e a Bioestatística. Esse guia proporciona informações úteis e objetivas a respeito de vários métodos estatísticos empregando exemplos relacionados à Odontologia e, mais especificamente, à Ortodontia. Esse tutorial deve ser empregado, principalmente, para o usuário obter algumas respostas a questões comuns relacionadas ao teste mais apropriado para executar comparações entre grupos, examinar correlações e regressões ou analisar o erro do método. Também pode ser obtido auxílio para checar a distribuição dos dados (normal ou anormal e a escolha do gráfico mais adequado para a apresentação dos resultados. Esse guia* pode ainda ser de bastante utilidade para revisores de periódicos examinarem, de forma rápida, a adequabilidade do método estatístico apresentado em um artigo submetido à publicação.Selecting appropriate methods for statistical analysis may be difficult, especially for the students and others in the early phases of the research career. On the other hand, PowerPoint presentation is a very common tool to researchers and dental students, so a statistical guide based on PowerPoint could narrow the gap between orthodontist and the Biostatistics. This guide provides objective and useful information about several statistical methods using examples related to the dental field. A Power-Point presentation is employed to assist the user to find answers to common questions regarding Biostatistics, such as the most appropriate statistical test to compare groups, to make correlations and

Statistical and fractal analysis of autofluorescent myocardium images in posthumous diagnostics of acute coronary insufficiency

Science.gov (United States)

Boichuk, T. M.; Bachinskiy, V. T.; Vanchuliak, O. Ya.; Minzer, O. P.; Garazdiuk, M.; Motrich, A. V.

2014-08-01

This research presents the results of investigation of laser polarization fluorescence of biological layers (histological sections of the myocardium). The polarized structure of autofluorescence imaging layers of biological tissues was detected and investigated. Proposed the model of describing the formation of polarization inhomogeneous of autofluorescence imaging biological optically anisotropic layers. On this basis, analytically and experimentally tested to justify the method of laser polarimetry autofluorescent. Analyzed the effectiveness of this method in the postmortem diagnosis of infarction. The objective criteria (statistical moments) of differentiation of autofluorescent images of histological sections myocardium were defined. The operational characteristics (sensitivity, specificity, accuracy) of these technique were determined.

Statistical power analysis for the behavioral sciences

National Research Council Canada - National Science Library

Cohen, Jacob

1988-01-01

... offers a unifying framework and some new data-analytic possibilities. 2. A new chapter (Chapter 11) considers some general topics in power analysis in more integrted form than is possible in the earlier...

Statistical power analysis for the behavioral sciences

National Research Council Canada - National Science Library

Cohen, Jacob

1988-01-01

.... A chapter has been added for power analysis in set correlation and multivariate methods (Chapter 10). Set correlation is a realization of the multivariate general linear model, and incorporates the standard multivariate methods...

Prevalence and Correlates of Vitamin D Deficiency and Insufficiency in Luxembourg Adults: Evidence from the Observation of Cardiovascular Risk Factors (ORISCAV-LUX Study

Directory of Open Access Journals (Sweden)

Ala'a Alkerwi

2015-08-01

Full Text Available Evidence on vitamin D status and related risk factors in Luxembourg adults is lacking. This study aimed to determine the prevalence of vitamin D deficiency and insufficiency and related risk factors among healthy adults in Luxembourg. Based on clinicians’ observations, it was hypothesized that vitamin D deficiency and insufficiency might be common in our population, constituting a significant public health concern. A nationally representative random sample of 1432 adults was enrolled in the ORISCAV-LUX study, 2007–2008. The participants were divided into four categories according to their serum concentrations of 25-hydroxyvitamin D [25(OHD]. Descriptive, univariate and multivariate statistical analyses used weighted methods to account for the stratified sampling scheme. Only 17.1% of the population had a “desirable” serum 25(OHD level ≥75 nmol/L, whereas 27.1% had “inadequate” [serum 25(OHD level 50–74 nmol/L], 40.4% had “insufficient” [serum 25(OHD level 25–49 nmol/L], and 15.5% had “deficient” [serum 25(OHD level <25 nmol/L]. The prevalence of vitamin D deficiency was greater among current smokers, obese subjects, those having reduced HDL-cholesterol level and fair/poor self-perception of health, compared to their counterparts. The prevalence of vitamin D insufficiency was additionally higher among nondrinkers of alcohol, Portuguese and subjects from non-European countries. The final multivariate logistic regression analyses revealed that smoking status and obesity were independent correlates of vitamin D deficiency and insufficiency, respectively. Inadequate vitamin D status is highly prevalent among adults in Luxembourg and is associated with specific lifestyle factors. Along with the effect of vitamin D deficiency and insufficiency on the risk of several diseases, cancer and mortality, our findings have practical implications for public health dietary recommendations, and of particular importance for healthcare

Prevalence and correlates of insufficient physical activity in school adolescents in Peru.

Science.gov (United States)

Sharma, Bimala; Chavez, Rosemary Cosme; Nam, Eun Woo

2018-01-01

OBJECTIVE To assess the prevalence and correlates of insufficient physical activity in adolescents in Peru. METHODS We used a self-administered questionnaire developed from Global school-based Student Health Survey to collect information from secondary school students in North Lima and Callao in 2015. We carried out Poisson regression with robust variance using generalized linear models to estimate the crude and adjusted prevalence ratios (APR) with 95% confidence intervals (95%CI) of insufficient physical activity for its correlates. RESULTS We have found that 78% of the adolescents did not meet the global recommendation of the World Health Organization on physical activity in the last week before the survey. Female respondents (APR = 1.13, 95%CI 1.04-1.21), respondents who perceived themselves as overweight (APR = 1.10, 95%CI 1.03-1.18), and respondents who consumed insufficient vegetables and fruits [no vegetables (APR = 1.30, 95%CI 1.06-1.59), no fruits (APR = 1.15, 95%CI 1.00-1.31) as compared to those who consumed ≥ 2 servings every day in the last seven days] were more likely to report insufficient physical activity. Adolescents who worked after school (APR = 0.92, 95%CI 0.84-0.99), had physical education classes five times per week (APR = 0.94, 95%CI 0.88-0.99), and had parental supervision (APR = 0.92, 95%CI 0.87-0.98) were less likely to report insufficient physical activity. CONCLUSIONS Sex, work after school, perceived body weight, physical education class, parental support, and healthy dietary behaviors were associated with insufficient physical activity. Attempts to improve physical activity should look for ways to enhance leisure-time physical activity, parental support, physical education classes, healthy dietary behaviors, and normal body weight maintenance in adolescents with integrated efforts from the family and school.

Sex differences in discriminative power of volleyball game-related statistics.

Science.gov (United States)

João, Paulo Vicente; Leite, Nuno; Mesquita, Isabel; Sampaio, Jaime

2010-12-01

To identify sex differences in volleyball game-related statistics, the game-related statistics of several World Championships in 2007 (N=132) were analyzed using the software VIS from the International Volleyball Federation. Discriminant analysis was used to identify the game-related statistics which better discriminated performances by sex. Analysis yielded an emphasis on fault serves (SC = -.40), shot spikes (SC = .40), and reception digs (SC = .31). Specific robust numbers represent that considerable variability was evident in the game-related statistics profile, as men's volleyball games were better associated with terminal actions (errors of service), and women's volleyball games were characterized by continuous actions (in defense and attack). These differences may be related to the anthropometric and physiological differences between women and men and their influence on performance profiles.

Energy statistics: Fourth quarter, 1989

International Nuclear Information System (INIS)

Anon.

1989-01-01

This volume contains 100 tables compiling data into the following broad categories: energy, drilling, natural gas, gas liquids, oil, coal, peat, electricity, uranium, and business indicators. The types of data that are given include production and consumption statistics, reserves, imports and exports, prices, fossil fuel and nuclear power generation statistics, and price indices

Diabetes mellitus and exocrine pancreatic insufficiency (review of literature

Directory of Open Access Journals (Sweden)

L.T. Daminova

2018-02-01

Full Text Available Currently, an increasing importance is given to the study of the problem of exocrine pancreatic insufficiency, which is observed in a significant number of patients with diabetes mellitus (DM type 1 and 2 and can potentially affect the compensation of DM. The mechanism of reducing the external secretion of the pancreas in DM is associated with an imbalance of inhibitory and stimulating pancreatic secretion of hormones, with fibrosis of the gland as a result of diabetic angiopathy. In type 2 DM, the mechanisms that result from the metabolic syndrome are involved in the pathogenesis of exocrine pancreatic insufficiency. Enzyme replacement the­rapy should be considered as one of the promising methods of treating DM patients.

Results of aortic root reimplantation in patients with ascending aortic aneurysm and concomitant aortic insufficiency

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А. М. Чернявский

2016-01-01

Full Text Available Objective. The research was designed to evaluate the results of valve-sparing operations: aortic root reimplantation versus aortic valve reimplantation when repairing an ascending aortic aneurysm with concomitant aortic insufficiency.Methods. Within a blind prospective randomized study conducted over a period from 2011 to 2015, 64 patients underwent aortic valve-sparing surgery. The inclusion criteria were the presence of an aortic aneurysm of the ascending aorta exceeding 4.5 cm and concomitant aortic insufficiency. All patients were divided into two groups: FS-group, aortic root reimplantation (modified Florida Sleeve technique (n = 32 and D-group, aortic valve reimplantation (David procedure (n = 32. The average age of patients was 57±13 (23–73 years in the FS-group and 55±11 (15–72 years in the D-group (p = 0.54. Both groups had 78% of males (p>0.99. A Marfan syndrome was identified in 6% and 9% in the FS-group and D-group respectively (p>0.99. Mean diameter of the sinuses of Valsalva was 51±7 mm and 56±10 mm (p = 0.09, aortic insufficiency 2.6±0.7 and 2.8±0.8 (p = 0.15 in the FS-group and D-group respectively. In the FS-group and D-group LVEDD amounted to 5.5±0.7 mm and 5.9±1.0 mm (p = 0.09 respectively. All patients took echocardiography in the preoperative, postoperative and follow-up periods.Results. In the long-term period, the degree of aortic regurgitation was 1.2±0.1 in the FS-group and 1.3±0.6 in the D-group (p = 0.72. LVEDD was 123±23 mm in the FS-group and 139.6±80 mm in the D-group at follow-up (p = 0.77. There were no statistically significant differences in the analysis of complications. Overall 30-day in-hospital mortality was 7.8%. There were 2 (6.3% deaths in the FS-group and 3 (9.4% in the D-group (p = 0.5.Late mortality was 6.3% in the FS-group and 3.1% in the D-group (p>0.99. Cumulative survival at 4 years was 84.3% and 84.8% in the FS-group and the D-group respectively (p = 0.94. Cumulative freedom from

Post-traumatic tricuspid valve insufficiency. 2 cases of delayed clinical manifestation.

OpenAIRE

Bortolotti, U; Scioti, G; Milano, A; Guglielmi, C; Benedetti, M; Tartarini, G; Balbarini, A

1997-01-01

We present 2 cases of tricuspid insufficiency following blunt chest trauma: 1 was diagnosed 5 months after the trauma and the other, 20 years after the trauma. In both patients, the tricuspid valve was replaced with a porcine bioprosthesis, because valve repair was not considered feasible. These cases emphasize the variability of clinical presentation of post-traumatic tricuspid valve insufficiency and indicate the need for close follow-up of patients after major thoracic trauma.

Statistics of dislocation pinning at localized obstacles

Energy Technology Data Exchange (ETDEWEB)

Dutta, A. [S. N. Bose National Centre for Basic Sciences, Salt Lake, Kolkata 700098 (India); Bhattacharya, M., E-mail: mishreyee@vecc.gov.in; Barat, P. [Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata 700064 (India)

2014-10-14

Pinning of dislocations at nanosized obstacles like precipitates, voids, and bubbles is a crucial mechanism in the context of phenomena like hardening and creep. The interaction between such an obstacle and a dislocation is often studied at fundamental level by means of analytical tools, atomistic simulations, and finite element methods. Nevertheless, the information extracted from such studies cannot be utilized to its maximum extent on account of insufficient information about the underlying statistics of this process comprising a large number of dislocations and obstacles in a system. Here, we propose a new statistical approach, where the statistics of pinning of dislocations by idealized spherical obstacles is explored by taking into account the generalized size-distribution of the obstacles along with the dislocation density within a three-dimensional framework. Starting with a minimal set of material parameters, the framework employs the method of geometrical statistics with a few simple assumptions compatible with the real physical scenario. The application of this approach, in combination with the knowledge of fundamental dislocation-obstacle interactions, has successfully been demonstrated for dislocation pinning at nanovoids in neutron irradiated type 316-stainless steel in regard to the non-conservative motion of dislocations. An interesting phenomenon of transition from rare pinning to multiple pinning regimes with increasing irradiation temperature is revealed.

Central Adrenal Insufficiency and Diabetes Insipidus Misdiagnosed as Severe Depression

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Naoki Hiroi

2010-01-01

Full Text Available A 68 year-old Japanese man, who had been suffering from immobilization and disuse syndrome, was admitted to our hospital for evaluation of polyuria with polyposia, hyponatremia and low blood pressure. His plasma osmolality was greater than that of his urine. His endocrinological examination revealed low levels of plasma adrenocorticotropic hormone (ACTH and cortisol, and a normal response of ACTH to the corticotrophin-releasing hormone (CRH challenge. Plasma ACTH did not increase with insulin loading. A low plasma vasopressin (AVP level and no response of AVP to a 5% saline administration were observed. We diagnosed central adrenal insufficiency with central diabetes insipidus. Six months after starting administration of hydrocortisone and 1-deamino-8D-arginine vasopressin, his psychological symptoms had improved, and 1.5 years after starting treatment, he was able to walk. In conclusion, it is not particularly rare for adrenal insufficiency to be misdiagnosed as depression. However, a correct early diagnosis is necessary, because, if adrenal insufficiency is not definitively diagnosed, the patient's quality of life diminishes markedly.

CLINICAL PROFILE OF NON-ALBUMINURIC RENAL INSUFFICIENCY IN TYPE 2 DIABETES MELLITUS IN A TERTIARY CARE HOSPITAL

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P. Sathya Murthy

2016-07-01

, electrolytes (Na, Cl, K, HCO3, LFT, urine routine examination, urine microalbumin, urine culture, USG abdomen, ECG, fundus assessment, calcium, phosphorus, uric acid. GFR was calculated in all the study population with Cockcroft–Gault formula and the study group was divided into different stages of CKD. STATISTICAL METHODS Categorical variables were expressed as number (% and continuous variables expressed as mean (SD, Range. Descriptive statistics (age, gender, comorbid illness, were explained using bar charts, pie diagrams. Correlation between two variables was checked using the Pearson's correlation coefficient method (HbA1c, GFR, Microalbumin. RESULTS In the present study, a total of 97 patients met the inclusion criteria. Among these 97 patients, 62 are male and 35 are female. The minimum and maximum age of the patient in the study group is 43 & 85. The mean age observed in the present study is 61.85. Among the study group of 97 participants, 68 (70.1 % had trace proteinuria in routine urine examination, while 29 (29.9 % had negative proteinuria in routine urine examination. The mean HbA1C value in the trace proteinuria is 9.80, and the mean value of HbA1c in the negative proteinuria group is 10.67. In the study population, 9 patients (9.27% are under CKD-3 as per KDOQI classification of the stages of CKD, 59 (60.8 % are under CKD-4, 29 (29.89 % are under CKD-5. In the study group of 97 patients, 54 had non-proliferative diabetic retinopathy, 43 had proliferative diabetic retinopathy. The minimum and maximum duration of diabetes in years in our study is 5 & 37. The mean value is 13.98. CONCLUSION Non-albuminuric renal insufficiency seems to be more prevalent among males more than 60 years of age. In this group, most of them were in CKD stage 4. Severity of the retinopathy correlated with the degree of renal insufficiency. Uncontrolled diabetes mellitus status (larger HbA1c value correlated with proliferative diabetic retinopathy than the larger duration of diabetes

Bedtime procrastination: a self-regulation perspective on sleep insufficiency in the general population

NARCIS (Netherlands)

Kroese, Floor|info:eu-repo/dai/nl/313869871; Evers, Catharine|info:eu-repo/dai/nl/280594232; Adriaanse, Marieke|info:eu-repo/dai/nl/304823023; de Ridder, Denise|info:eu-repo/dai/nl/070706174

2016-01-01

Getting insufficient sleep has serious consequences in terms of mental and physical health. The current study is the first to approach insufficient sleep from a self-regulation perspective by investigating the phenomenon of bedtime procrastination: going to bed later than intended, without having

Statistics

International Nuclear Information System (INIS)

2005-01-01

For the years 2004 and 2005 the figures shown in the tables of Energy Review are partly preliminary. The annual statistics published in Energy Review are presented in more detail in a publication called Energy Statistics that comes out yearly. Energy Statistics also includes historical time-series over a longer period of time (see e.g. Energy Statistics, Statistics Finland, Helsinki 2004.) The applied energy units and conversion coefficients are shown in the back cover of the Review. Explanatory notes to the statistical tables can be found after tables and figures. The figures presents: Changes in GDP, energy consumption and electricity consumption, Carbon dioxide emissions from fossile fuels use, Coal consumption, Consumption of natural gas, Peat consumption, Domestic oil deliveries, Import prices of oil, Consumer prices of principal oil products, Fuel prices in heat production, Fuel prices in electricity production, Price of electricity by type of consumer, Average monthly spot prices at the Nord pool power exchange, Total energy consumption by source and CO 2 -emissions, Supplies and total consumption of electricity GWh, Energy imports by country of origin in January-June 2003, Energy exports by recipient country in January-June 2003, Consumer prices of liquid fuels, Consumer prices of hard coal, natural gas and indigenous fuels, Price of natural gas by type of consumer, Price of electricity by type of consumer, Price of district heating by type of consumer, Excise taxes, value added taxes and fiscal charges and fees included in consumer prices of some energy sources and Energy taxes, precautionary stock fees and oil pollution fees

A study of the optimum draft of multiple resonance power buoys for maximizing electric power production

Directory of Open Access Journals (Sweden)

Hyuck-Min Kweon

2014-12-01

Full Text Available To maximize electric power production using wave energy extractions from resonance power buoys, the maximum motion displacement spectra of the buoys can primarily be obtained under a given wave condition. In this study, wave spectra observed in shoaling water were formulated. Target resonance frequencies were established from the arithmetic means of modal frequency bands and the peak frequencies. The motion characteristics of the circular cylindrical power buoys with corresponding drafts were then calculated using numerical models without considering PTO damping force. Results showed that the heave motions of the power buoys in shoaling waters with insufficient drafts produced greater amplification effects than those in deep seas with sufficient drafts.

Danish electricity supply. Statistics 2003

International Nuclear Information System (INIS)

2004-01-01

The Association of Danish Electric Utilities each year issues the statistical yearbook 'Danish electricity supply'. By means of brief text, figures, and tables a description is given of the electric supply sector. The report presents data for the year 2003 for consumption, prices of electric power, power generation and transmission, and trade. (ln)

Danish electricity supply. Statistics 2000

International Nuclear Information System (INIS)

2001-07-01

The Association of Danish Electric Utilities each year issues the statistical yearbook 'Danish electricity supply'. By means of brief text, figures, and tables a description is given of the electric supply sector. The report presents data for the year 2000 for consumption, prices of electric power; power generation and transmission, and trade. (ln)

Danish electricity supply. Statistics 2002

International Nuclear Information System (INIS)

2003-01-01

The Association of Danish Electric Utilities each year issues the statistical yearbook 'Danish electricity supply'. By means of brief text, figures, and tables a description is given of the electric supply sector. The report presents data for the year 2002 for consumption, prices of electric power; power generation and transmission, and trade. (ln)

Statistics for nuclear engineers and scientists. Part 1. Basic statistical inference

Energy Technology Data Exchange (ETDEWEB)

Beggs, W.J.

1981-02-01

This report is intended for the use of engineers and scientists working in the nuclear industry, especially at the Bettis Atomic Power Laboratory. It serves as the basis for several Bettis in-house statistics courses. The objectives of the report are to introduce the reader to the language and concepts of statistics and to provide a basic set of techniques to apply to problems of the collection and analysis of data. Part 1 covers subjects of basic inference. The subjects include: descriptive statistics; probability; simple inference for normally distributed populations, and for non-normal populations as well; comparison of two populations; the analysis of variance; quality control procedures; and linear regression analysis.

The intermediates take it all: asymptotics of higher criticism statistics and a powerful alternative based on equal local levels.

Science.gov (United States)

Gontscharuk, Veronika; Landwehr, Sandra; Finner, Helmut

2015-01-01

The higher criticism (HC) statistic, which can be seen as a normalized version of the famous Kolmogorov-Smirnov statistic, has a long history, dating back to the mid seventies. Originally, HC statistics were used in connection with goodness of fit (GOF) tests but they recently gained some attention in the context of testing the global null hypothesis in high dimensional data. The continuing interest for HC seems to be inspired by a series of nice asymptotic properties related to this statistic. For example, unlike Kolmogorov-Smirnov tests, GOF tests based on the HC statistic are known to be asymptotically sensitive in the moderate tails, hence it is favorably applied for detecting the presence of signals in sparse mixture models. However, some questions around the asymptotic behavior of the HC statistic are still open. We focus on two of them, namely, why a specific intermediate range is crucial for GOF tests based on the HC statistic and why the convergence of the HC distribution to the limiting one is extremely slow. Moreover, the inconsistency in the asymptotic and finite behavior of the HC statistic prompts us to provide a new HC test that has better finite properties than the original HC test while showing the same asymptotics. This test is motivated by the asymptotic behavior of the so-called local levels related to the original HC test. By means of numerical calculations and simulations we show that the new HC test is typically more powerful than the original HC test in normal mixture models. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Adrenal insufficiency in a child with MELAS syndrome.

Science.gov (United States)

Afroze, Bushra; Amjad, Nida; Ibrahim, Shahnaz H; Humayun, Khadija Nuzhat; Yakob, Yusnita

2014-11-01

Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) are established subgroups of mitochondrial encephalomyopathy. m.3243A>G a common point mutation is detected in tRNA in majority of patients with MELAS phenotype whereas m.8344A>G point mutation in tRNA is observed, in MERRF phenotype. Adrenal insufficiency has not been reported in mitochondrial disease, except in Kearns-Sayre Syndrome (KSS), which is a mitochondrial deletion syndrome. We report an unusual presentation in a five year old boy who presented with clinical phenotype of MELAS and was found to have m.8344A>G mutation in tRNA. Addison disease was identified due to hyperpigmentation of lips and gums present from early childhood. This is the first report describing adrenal insufficiency in a child with MELAS phenotype. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Clinical significance of gamma camera renography in chronic renal insufficiency

International Nuclear Information System (INIS)

Dudczak, R.; Frischauf, H.; Kletter, K.

1980-01-01

Gamma camera renography allows, together with renal imaging, an evaluation of individual renal function. For these examinations, I 123 orthoiodohippurate is preferred and most widely used. The results on patients with chronic renal insufficiency, including urologic and posttransplantation patients, are reported. Whereas the method is of clinical significance in evaluating posttransplantation complications and in assessing individual kidney function preoperatively in urology, as well as in monitoring therapeutic effects in the early period of renal disease, it is of limited diagnostic value in chronic renal insufficiency. In this latter regard, clinical and laboratory examinations are of primary importance. (author)

Electric power annual 1995. Volume II

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-12-01

This document summarizes pertinent statistics on various aspects of the U.S. electric power industry for the year and includes a graphic presentation. Data is included on electric utility retail sales and revenues, financial statistics, environmental statistics of electric utilities, demand-side management, electric power transactions, and non-utility power producers.

Basic statistics an introduction with R

CERN Document Server

Raykov, Tenko

2012-01-01

Basic Statistics provides an accessible and comprehensive introduction to statistics using the free, state-of-the-art, powerful software program R. This book is designed to both introduce students to key concepts in statistics and to provide simple instructions for using R.Teaches essential concepts in statistics, assuming little background knowledge on the part of the readerIntroduces students to R with as few sub-commands as possible for ease of useProvides practical examples from the educational, behavioral, and social sciencesBasic Statistics will appeal to students and professionals acros

Electric power annual, 1990

International Nuclear Information System (INIS)

1992-01-01

The Electric Power Annual presents a summary of electric utility statistics at the national, regional and State levels. The objective of the publication is to provide industry decisionmakers, government policy-makers, analysts and the general public with historical data that may be used in understanding US electricity markets. ''The Industry at a Glance'' section presents a profile of the electric power industry ownership and performance; a review of key statistics for the year; and projections for various aspects of the electric power industry through 2010. Subsequent sections present data on generating capability, including proposed capability additions; net generation; fossil-fuel statistics; electricity sales, revenue, and average revenue per kilowatthour sold; financial statistics; environmental statistics; and electric power transactions. In addition, appendices provide supplemental data on major disturbances and unusual occurrences. Each section contains related text and tables and refers the reader to the appropriate publication that contains more detailed data on the subject matter

Pancreatic exocrine insufficiency, diabetes mellitus and serum nutritional markers after acute pancreatitis.

Science.gov (United States)

Vujasinovic, Miroslav; Tepes, Bojan; Makuc, Jana; Rudolf, Sasa; Zaletel, Jelka; Vidmar, Tjasa; Seruga, Maja; Birsa, Bostjan

2014-12-28

To investigate impairment and clinical significance of exocrine and endocrine pancreatic function in patients after acute pancreatitis (AP). Patients with AP were invited to participate in the study. Severity of AP was determined by the Atlanta classification and definitions revised in 2012. Pancreatic exocrine insufficiency (PEI) was diagnosed by the concentration of fecal elastase-1. An additional work-up, including laboratory testing of serum nutritional markers for determination of malnutrition, was offered to all patients with low levels of fecal elastase-1 FE. Hemoglobin A1c or oral glucose tolerance tests were also performed in patients without prior diabetes mellitus, and type 3c diabetes mellitus (T3cDM) was diagnosed according to American Diabetes Association criteria. One hundred patients were included in the study: 75% (75/100) of patients had one attack of AP and 25% (25/100) had two or more attacks. The most common etiology was alcohol. Mild, moderately severe and severe AP were present in 67, 15 and 18% of patients, respectively. The mean time from attack of AP to inclusion in the study was 2.7 years. PEI was diagnosed in 21% (21/100) of patients and T3cDM in 14% (14/100) of patients. In all patients with PEI, at least one serologic nutritional marker was below the lower limit of normal. T3cDM was more frequently present in patients with severe AP (P = 0.031), but was also present in some patients with mild and moderately severe AP. PEI was present in all degrees of severity of AP. There were no statistically significantly differences according to gender, etiology and number of AP attacks. As exocrine and endocrine pancreatic insufficiency can develop after AP, routine follow-up of patients is necessary, for which serum nutritional panel measurements can be useful.

Percutaneous treatment of insufficiency fractures. Principles, technique and review of literature

International Nuclear Information System (INIS)

Beall, Douglas P.; Datir, Abhijit; D'Souza, Sharon L.; D'Souza, Logan S.; Gunda, Divya; Morelli, John; Johnson, Michael Brandon; Nabavizadeh, Nima

2010-01-01

Insufficiency fractures of the pelvis, sacrum, spine, and long bones are painful, debilitating, and are common consequences of osteoporosis. Conventional treatment for these fractures varies from conservative therapy to surgery with plate and screw fixation. The former fails to address the underlying problem of fracture and frequently does not alleviate symptoms, while the latter is invasive and not always possible in older populations with low bone density and numerous co-morbidities. Osseous augmentation with polymethylmethacrylate (PMMA) has been used for over two decades to treat fractures related to osteoporosis, but has not been commonly used to treat fractures outside of the vertebral bodies. Osseous augmentation with PMMA is an image-guided procedure and various techniques have been utilized to treat fracture in different locations. We describe various techniques for image-guided osseous augmentation and treatment of insufficiency fractures with bothPMMA and allograft bone for fractures of the pelvis including sacrum, acetabulum, pubic symphysis, pubic rami ilium; appendicular skeleton including distal radius, proximal femur, and vertebral body. We also describe the potential risks and complications associated with percutaneous treatment of insufficiency fractures and techniques to avoid the pitfalls of the various procedures. We will present the process for patient follow-up and data regarding the pre- and postprocedure pain response in patients undergoing treatment for pelvic insufficiency fractures. (orig.)

Prevalence and Predictors of Functional Vitamin K Insufficiency in Mothers and Newborns in Uganda

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Data Santorino

2015-10-01

Full Text Available Vitamin K deficiency bleeding (VKDB in infancy is a serious but preventable cause of mortality or permanent disability. Lack of epidemiologic data for VKDB in sub-Saharan Africa hinders development and implementation of effective prevention strategies. We used convenience sampling to consecutively enroll mothers delivering in a southwestern Uganda Hospital. We collected socio-demographic and dietary information, and paired samples of maternal venous and neonatal cord blood for the immunoassay of undercarboxylated prothrombin (PIVKA-II, a sensitive marker of functional vitamin K (VK insufficiency. We used univariable and multivariable logistic regression models to identify predictors of VK insufficiency. We detected PIVKA-II of ≥0.2 AU (Arbitrary Units per mL/mL (indicative of VK insufficiency in 33.3% (47/141 of mothers and 66% (93/141 of newborns. Importantly, 22% of babies had PIVKA-II concentrations ≥5.0 AU/mL, likely to be associated with abnormal coagulation indices. We found no significant predictors of newborn VK insufficiency, including infant weight (AOR (adjusted odds ratio 1.85, 95% CI (confidence interval 0.15–22.49, gender (AOR 0.54, 95% CI 0.26–1.11, term birth (AOR 0.72, 95% CI 0.20–2.62, maternal VK-rich diet (AOR 1.13, 95% CI 0.55–2.35 or maternal VK insufficiency (AOR 0.99, 95% CI 0.47–2.10. VK insufficiency is common among mothers and newborn babies in southwestern Uganda, which in one fifth of babies nears overt deficiency. Lack of identifiable predictors of newborn VK insufficiency support strategies for universal VK prophylaxis to newborns to prevent VKDB.

Elementary Statistics Tables

CERN Document Server

Neave, Henry R

2012-01-01

This book, designed for students taking a basic introductory course in statistical analysis, is far more than just a book of tables. Each table is accompanied by a careful but concise explanation and useful worked examples. Requiring little mathematical background, Elementary Statistics Tables is thus not just a reference book but a positive and user-friendly teaching and learning aid. The new edition contains a new and comprehensive "teach-yourself" section on a simple but powerful approach, now well-known in parts of industry but less so in academia, to analysing and interpreting process dat

Insurance of nuclear power stations

International Nuclear Information System (INIS)

Debaets, M.

1992-01-01

Electrical utility companies have invested large sums in the establishment of nuclear facilities. For this reason it is normal for these companies to attempt to protect their investments as much as possible. One of the methods of protection is recourse to insurance. For a variety of reasons traditional insurance markets are unable to function normally for a number of reasons including, the insufficient number of risks, an absence of meaningful accident statistics, the enormous sums involved and a lack of familiarity with nuclear risks on the part of insurers, resulting in a reluctance or even refusal to accept such risks. Insurers have, in response to requests for coverage from nuclear power station operators, established an alternative system of coverage - insurance through a system of insurance pools. Insurers in every country unite in a pool, providing a net capacity for every risk which is a capacity covered by their own funds, and consequently without reinsurance. All pools exchange capacity. The inconvenience of this system, for the operators in particular, is that it involves a monopolistic system in which there are consequently few possibilities for the negotiation of premiums and conditions of coverage. The system does not permit the establishment of reserves which could, over time, reduce the need for insurance on the part of nuclear power station operators. Thus the cost of nuclear insurance remains high. Alternatives to the poor system of insurance are explored in this article. (author)

Food insufficiency is associated with high-risk sexual behavior among women in Botswana and Swaziland.

Directory of Open Access Journals (Sweden)

Sheri D Weiser

2007-10-01

Full Text Available Both food insufficiency and HIV infection are major public health problems in sub-Saharan Africa, yet the impact of food insufficiency on HIV risk behavior has not been systematically investigated. We tested the hypothesis that food insufficiency is associated with HIV transmission behavior.We studied the association between food insufficiency (not having enough food to eat over the previous 12 months and inconsistent condom use, sex exchange, and other measures of risky sex in a cross-sectional population-based study of 1,255 adults in Botswana and 796 adults in Swaziland using a stratified two-stage probability design. Associations were examined using multivariable logistic regression analyses, clustered by country and stratified by gender. Food insufficiency was reported by 32% of women and 22% of men over the previous 12 months. Among 1,050 women in both countries, after controlling for respondent characteristics including income and education, HIV knowledge, and alcohol use, food insufficiency was associated with inconsistent condom use with a nonprimary partner (adjusted odds ratio [AOR] 1.73, 95% confidence interval [CI] 1.27-2.36, sex exchange (AOR 1.84, 95% CI 1.74-1.93, intergenerational sexual relationships (AOR 1.46, 95% CI 1.03-2.08, and lack of control in sexual relationships (AOR 1.68, 95% CI 1.24-2.28. Associations between food insufficiency and risky sex were much attenuated among men.Food insufficiency is an important risk factor for increased sexual risk-taking among women in Botswana and Swaziland. Targeted food assistance and income generation programs in conjunction with efforts to enhance women's legal and social rights may play an important role in decreasing HIV transmission risk for women.

Children Receiving Free or Reduced-Price School Lunch Have Higher Food Insufficiency Rates in Summer.

Science.gov (United States)

Huang, Jin; Barnidge, Ellen; Kim, Youngmi

2015-09-01

In 2012, 20% of households in the United States with children lacked consistent access to adequate food. Food insufficiency has significant implications for children, including poor physical and mental health outcomes, behavior problems, and low educational achievements. The National School Lunch Program (NSLP) is one policy solution to reduce food insufficiency among children from low-income families. The objective of this project was to evaluate the association between NSLP participation and household food insufficiency by examining trajectories of food insufficiency over 10 calendar months. The calendar months included both nonsummer months when school is in session and summer months when school is out of session. The study used the data from the Survey of Income and Program Participation and conducted linear growth curve analyses in the multilevel modeling context. Comparisons were made between the trajectories of food insufficiencies among recipients of free or reduced-price lunch and their counterparts who are eligible but choose not to participate in the program. Heads of households that included children receiving free or reduced-price lunch (n = 6867) were more likely to be female, black, unmarried, and unemployed, and have a lower educational attainment than those whose children were eligible but did not receive free or reduced-price lunch (n = 11,396). For households participating in the NSLP, the food insufficiency rate was consistent from January to May at ∼4%, and then increased in June and July to >5%. Meanwhile, food insufficiency among eligible nonrecipients was constant throughout the year at nearly 2%. The NSLP protects households from food insufficiency. Policies should be instituted to make enrollment easier for households. © 2015 American Society for Nutrition.

Spontaneous osteonecrosis of the knee associated with tibial plateau and femoral condyle insufficiency stress fracture

Energy Technology Data Exchange (ETDEWEB)

Narvaez, J.A.; Narvaez, J.; Lama, E.De; Sanchez, A. [Department of Magnetic Resonance Imaging, IDI Hospital Duran i Reynals, Ciutat Sanitaria i Universitaria de Bellvitge, Gran Via s/n, 08907, L' Hospitalet de Llobregat (Barcelona) (Spain)

2003-08-01

The purpose of this article is to describe the association between spontaneous osteonecrosis and insufficiency stress fractures of the knee. To determine whether insufficiency stress fracture is associated with spontaneous osteonecrosis of the knee, we retrospectively reviewed the medical charts and imaging studies of all patients with spontaneous osteonecrosis of the knee, studied by MR imaging, seen in a tertiary hospital over an 8-year period. Four women (age range 66-84 years) presented spontaneous osteonecrosis of the knee associated with insufficiency stress fracture of the medial tibial plateau. One of these patients also presented a concomitant insufficiency stress fracture of the medial femoral condyle. Radiographs were diagnostic of spontaneous osteonecrosis of the medial femoral condyle in three cases, and insufficiency stress fracture of the medial tibial plateau was detected in one case. Magnetic resonance imaging allows the diagnosis of both conditions in all four cases. Spontaneous osteonecrosis of the knee may be associated with insufficiency stress fracture of the medial femoral condyle and the medial tibial plateau. This association provides additional arguments in favor of the traumatic etiology of spontaneous osteonecrosis of knee. (orig.)

Spontaneous osteonecrosis of the knee associated with tibial plateau and femoral condyle insufficiency stress fracture

International Nuclear Information System (INIS)

Narvaez, J.A.; Narvaez, J.; Lama, E.De; Sanchez, A.

2003-01-01

The purpose of this article is to describe the association between spontaneous osteonecrosis and insufficiency stress fractures of the knee. To determine whether insufficiency stress fracture is associated with spontaneous osteonecrosis of the knee, we retrospectively reviewed the medical charts and imaging studies of all patients with spontaneous osteonecrosis of the knee, studied by MR imaging, seen in a tertiary hospital over an 8-year period. Four women (age range 66-84 years) presented spontaneous osteonecrosis of the knee associated with insufficiency stress fracture of the medial tibial plateau. One of these patients also presented a concomitant insufficiency stress fracture of the medial femoral condyle. Radiographs were diagnostic of spontaneous osteonecrosis of the medial femoral condyle in three cases, and insufficiency stress fracture of the medial tibial plateau was detected in one case. Magnetic resonance imaging allows the diagnosis of both conditions in all four cases. Spontaneous osteonecrosis of the knee may be associated with insufficiency stress fracture of the medial femoral condyle and the medial tibial plateau. This association provides additional arguments in favor of the traumatic etiology of spontaneous osteonecrosis of knee. (orig.)

Pentoxifylline in the treatment of radiation-related pelvic insufficiency fractures of bone

International Nuclear Information System (INIS)

Bese, N.S.; Oezgueroglu, M.; Kamberoglu, K.; Karahasanoglu, T.; Oeber, A.

2003-01-01

The reported incidence of bone complications after radiation therapy is quite low. The most commonly seen bone complication is insufficiency fractures of the pubis and sacrum. Treatment of insufficiency fractures consists of conservative care, and mineral replacement may be useful. The resolution of symptoms takes at least one year with these treatments. Vascular damage has an important role in the etiology of late radiation injury in normal tissues. Progressive ischemic changes further weaken the bone structure, which can cause fractures, and healing is also delayed. Pentoxifylline is a methylxanthine derivative that is shown to increase tissue blood flow. Here, we present a 63-year-old male patient with pelvic insufficiency fractures due to postoperative pelvic irradiation for rectal adenocarcinoma. The patient received pelvic radiotherapy to a total dose of 50.4 Gy with concomitant 5-FU. Six months after the completion of radiotherapy, the patient presented with severe pelvic pain. Pelvic magnetic resonance imaging (MRI) demonstrated abnormal signal intensity with insufficiency fractures at the sacrum and bone marrow edema near the fractures, but not an abnormal intensity that revealed bone metastases. Neither distant nor locoregional recurrence was observed at his work-up. The final diagnosis was insufficiency fractures of the pelvic bones owing to irradiation, and pentoxifylline (400 mg, 3 times daily, peroral, 1,200 mg/day) was used for eight months as treatment. Dramatic clinical improvement was obtained in six months, and objective healing was revealed with MRI. We concluded that pentoxifylline is a cost-effective drug with minimal adverse effects in treating radiation damage of bone. (author)

Female androgen insufficiency: the Princeton consensus statement on definition, classification, and assessment.

Science.gov (United States)

Bachmann, Gloria; Bancroft, John; Braunstein, Glenn; Burger, Henry; Davis, Susan; Dennerstein, Lorraine; Goldstein, Irwin; Guay, Andre; Leiblum, Sandra; Lobo, Rogerio; Notelovitz, Morris; Rosen, Raymond; Sarrel, Philip; Sherwin, Barbara; Simon, James; Simpson, Evan; Shifren, Jan; Spark, Richard; Traish, Abdul

2002-04-01

To evaluate the evidence for and against androgen insufficiency as a cause of sexual and other health-related problems in women and to make recommendations regarding definition, diagnosis, and assessment of androgen deficiency states in women. Evaluation of peer-review literature and consensus conference of international experts. Multinational conference in the United States. Premenopausal and postmenopausal women with androgen deficiency. Evaluation of peer-review literature and development of consensus panel guidelines. The term "female androgen insufficiency" was defined as consisting of a pattern of clinical symptoms in the presence of decreased bioavailable T and normal estrogen status. Currently available assays were found to be lacking in sensitivity and reliability at the lower ranges, and the need for an equilibrium dialysis measure was strongly emphasized. Causes of androgen insufficiency in women were classified as ovarian, adrenal, hypothalamic-pituitary, drug-related, and idiopathic. A simplified management algorithm and clinical guidelines were proposed to assist clinicians in diagnosis and assessment. Androgen replacement is currently available in several forms, although none has been approved for treatment of sexual dysfunction or other common symptoms of female androgen insufficiency. Potential risks associated with treatment were identified, and the need for informed consent and careful monitoring was noted. Finally, the panel identified key goals and priorities for future research. A new definition of androgen insufficiency in women has been proposed along with consensus-based guidelines for clinical assessment and diagnosis. A simplified management algorithm for women with low androgen in the presence of clinical symptoms and normal estrogen status has also been proposed.

Wind power in areas with limited export capability

Energy Technology Data Exchange (ETDEWEB)

Matevosyan, Julija

2004-03-01

During the last two decades, increase in electricity demand and environmental concern resulted in fast growth of power production from renewable sources. Wind power is one of the most efficient alternatives. Due to rapid development of wind turbine technology and increasing size of wind farms, wind power plays a significant part in the power production mix of Germany, Spain, Denmark and some other countries. Wind power has to be build in areas with good wind potential. The best conditions for installation of wind power are, thus, in remote areas free of obstacles, and consequently with low population density. The transmission system in such areas might not be dimensioned to accommodate additional large-scale power plants. Insufficient transmission capacity problem, however, would emerge for any type of new generation, planned in similar conditions, although wind power has some special features that should be considered solving this problem. In this thesis the four possibilities are considered. One possibility is to revise the methods for calculation of available transmission capacity. Another solution for large-scale integration of wind power in such areas is to reinforce the network. This alternative however may be expensive and time consuming. Since wind power production depends on the wind speed, the wind farm utilization time is only 2,000-4,000 hours a year, and power production peaks not necessarily occur during periods with insufficient transmission capacity. Therefore wind energy curtailment may be considered as an alternative for large-scale wind power integration. It is also possible to store excess wind energy during the periods with insufficient transmission capacity. Conventional power plants with possibilities of fast production control (e.g. hydropower plants or gas power plants) may also be employed for this purpose. There is a lot of research regarding first two measures, therefore, this thesis provides a review and summarized conclusions from the

Pelvic insufficiency fractures associated with radiation atrophy: clinical recognition and diagnostic evaluation

International Nuclear Information System (INIS)

Mumber, M.P.; Greven, K.M.; Haygood, T.M.

1997-01-01

Pelvic bone injuries are infrequent complications of radiotherapy. However, insufficiency fractures in irradiated pelvic bones may be underdetected, particularly in postmenopausal women. We describe the clinical presentation, radiologic evaluation, and course of disease in three patients with postradiation pelvic insufficiency fractures. Differential diagnosis included metastatic disease, tumor recurrence, and second malignancy. Recognition of radiographic features may prevent unnecessary, possibly morbid treatments. (orig.). With 6 figs

Characterization of the cable fire in Block 1 of the Greifswald nuclear power plant

International Nuclear Information System (INIS)

Albrecht, L.; Gelfort, E.

1996-01-01

In December 1975 a cable fire was initiated in a stand-by power distribution by a short circuit and an incorrectly fitted diode. Unpredictably and accidentally, some control and power cables were destroyed during the fire. This caused the failure of safety-relevant components. Decay heat removal was achieved initially by natural convection in the primary loop, and finally by an emergency feed pump in the secondary loop, for which a preovisional power cable had been successfully installed after approximately 8.5 hours. This serious accident was caused by human failure and lack of experience, by the insufficiency of the redundancies as provided in the plant design, by the lack of spatial separation of safety systems, and by insufficient quality control. (orig.) [de

Vitamin D insufficiency in the elderly orthopaedic patient: an epidemic phenomenon.

Science.gov (United States)

Maier, Gerrit Steffen; Horas, Konstantin; Seeger, Jörn Bengt; Roth, Klaus Edgar; Kurth, Andreas Alois; Maus, Uwe

2015-04-01

The purpose of this observational study was to evaluate serum levels of 25-OH-D of elderly patients presenting with orthopaedic illness. Furthermore, we enquired about potential confounders and risk factors of hypovitaminosis D in comorbidities and daily medication of the elderly. Vitamin D levels in 1,083 patients aged >70 years and admitted to an orthopaedic surgery department were measured. Univariate and multivariate analyses were used to assess risk factors for insufficient vitamin D levels. Overall, 86 % of patients had insufficient serum levels of 25-OH-D and >60 % were vitamin D deficient. Serum vitamin D levels were lower during winter and months with fewer sunshine hours. Patients presenting with obesity, hypertension and osteoporosis were more likely to have low vitamin D levels. We found a high prevalence of hypovitaminosis D in elderly, nonhospitalized orthopaedic patients. Given the well-known effects of vitamin D on bone metabolism and muscle health, as well as its nonskeletal effects, vitamin D insufficiency may have a negative impact.

Annual statistical information 1996; Informe estatistico anual 1996

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-31

This annual statistical report aims to propagate the information about the generation, transmission and distribution systems evolution and about the electric power market from the Parana State, Brazil, in 1996. The electric power consumption in the distribution area of the Parana Power Company (COPEL) presented a growth about 6,7%. The electric power production in the the COPEL plants increased 42,2% higher than 1995, due to the outflows verified in the Iguacu river and to the long period of the affluence reduction that the Southern region tanks coursed during this year. This report presents statistical data about the following topics: a) electric power energy balance from the Parana State; b) electric power energy balance from the COPEL - own generation, certain interchange, electric power requirement, direct distribution and the electric system 6 graphs, 3 maps, 61 tabs.; e-mail: splcnmr at mail.copel.br

Prevalence and effects of functional vitamin K insufficiency

NARCIS (Netherlands)

Riphagen, Ineke J.; Keyzer, Charlotte A.; Drummen, Nadja E.A.; Borst, de Martin H.; Beulens, Joline W.J.; Gansevoort, Ron T.; Geleijnse, Johanna M.; Muskiet, Frits A.J.; Navis, Gerjan; Visser, Sipke T.; Vermeer, Cees; Kema, Ido P.; Bakker, Stephan J.L.

2017-01-01

Matrix Gla Protein (MGP) is a strong vitamin K-dependent inhibitor of soft tissue calcification. We assessed the prevalence of functional vitamin K insufficiency, as derived from plasma desphospho-uncarboxylated MGP (dp-ucMGP), and investigated whether plasma dp-ucMGP is associated with all-cause

Health consequences of shift work and insufficient sleep

NARCIS (Netherlands)

Kecklund, L.G.; Axelsson, J.

2016-01-01

This review summarises the literature on shift work and its relation to insufficient sleep, chronic diseases, and accidents. It is based on 38 meta-analyses and 24 systematic reviews, with additional narrative reviews and articles used for outlining possible mechanisms by which shift work may cause

A Comparison of the Performance of Advanced Statistical Techniques for the Refinement of Day-ahead and Longer NWP-based Wind Power Forecasts

Science.gov (United States)

Zack, J. W.

2015-12-01

Predictions from Numerical Weather Prediction (NWP) models are the foundation for wind power forecasts for day-ahead and longer forecast horizons. The NWP models directly produce three-dimensional wind forecasts on their respective computational grids. These can be interpolated to the location and time of interest. However, these direct predictions typically contain significant systematic errors ("biases"). This is due to a variety of factors including the limited space-time resolution of the NWP models and shortcomings in the model's representation of physical processes. It has become common practice to attempt to improve the raw NWP forecasts by statistically adjusting them through a procedure that is widely known as Model Output Statistics (MOS). The challenge is to identify complex patterns of systematic errors and then use this knowledge to adjust the NWP predictions. The MOS-based improvements are the basis for much of the value added by commercial wind power forecast providers. There are an enormous number of statistical approaches that can be used to generate the MOS adjustments to the raw NWP forecasts. In order to obtain insight into the potential value of some of the newer and more sophisticated statistical techniques often referred to as "machine learning methods" a MOS-method comparison experiment has been performed for wind power generation facilities in 6 wind resource areas of California. The underlying NWP models that provided the raw forecasts were the two primary operational models of the US National Weather Service: the GFS and NAM models. The focus was on 1- and 2-day ahead forecasts of the hourly wind-based generation. The statistical methods evaluated included: (1) screening multiple linear regression, which served as a baseline method, (2) artificial neural networks, (3) a decision-tree approach called random forests, (4) gradient boosted regression based upon an decision-tree algorithm, (5) support vector regression and (6) analog ensemble

Evaluation of Neutrophil–Lymphocyte Ratio, Platelet–Lymphocyte Ratio and Red Blood Cell Distribution Width–Platelet Ratio for Diagnosis of Premature Ovarian Insufficiency

Directory of Open Access Journals (Sweden)

Gülşah Ilhan

2017-03-01

Full Text Available Objective: To evaluate whether systemic inflammatory markers (neutrophil to lymphocyte ratio (NLR, platelet to lymphocyte ratio (PLR and red blood cell distribution width (RDW to platelet ratio (RPR can be used as reliable markers for the diagnosis of premature ovarian insufficiency (POI and to determine if there is a relationship between these markers and follicle stimulating hormone (FSH, Anti-Müllerian Hormone (AMH levels.Materials and methods: Written and electronic medical records were reviewed using searches for diagnoses with the terms of 'premature ovarian failure', 'premature ovarian insufficiency'. Patients younger than the age of 40 were diagnosed to have premature ovarian insufficiency based on their menstrual history and sonographic examination and they were compared with healthy females. Complete blood counts, day-3 hormone profiles, AMH levels of all subjects were analyzed.Results: NLR was statistically higher in POI group compared with controls (p < 0.05. NLR had a positive correlation between FSH (r = 0.23, p = 0.045 and a negative association with AMH (r = - 0.27, p = 0.018. The area under ROC curve for NLR in POI was 0.66, with a threshold value 1.5 and sensitivity = 75.7 % and specificity = 46.0 %.Conclusion: NLR can be a marker for the diagnosis of POI. There is a close relationship between NLR and ovarian reserve markers such as FSH and AMH.

Vitamin D deficiency and insufficiency among patients with prostate cancer.

Science.gov (United States)

Trump, Donald L; Chadha, Manpreet K; Sunga, Annette Y; Fakih, Marwan G; Ashraf, Umeer; Silliman, Carrie G; Hollis, Bruce W; Nesline, Mary K; Tian, Lili; Tan, Wei; Johnson, Candace S

2009-10-01

To assess the frequency of vitamin D deficiency among men with prostate cancer, as considerable epidemiological, in vitro, in vivo and clinical data support an association between vitamin D deficiency and prostate cancer outcome. The study included 120 ambulatory men with recurrent prostate cancer and 50 with clinically localized prostate cancer who were evaluated and serum samples assayed for 25-OH vitamin D levels. Then 100 controls (both sexes), matched for age and season of serum sample, were chosen from a prospective serum banking protocol. The relationship between age, body mass index, disease stage, Eastern Cooperative Oncology Group performance status, season and previous therapy on vitamin D status were evaluated using univariate and multivariate analyses. The mean 25-OH vitamin D level was 25.9 ng/mL in those with recurrent disease, 27.5 ng/mL in men with clinically localized prostate cancer and 24.5 ng/mL in controls. The frequency of vitamin D deficiency (<20 ng/mL) and insufficiency (20-31 ng/mL) was 40% and 32% in men with recurrent prostate; 28% had vitamin D levels that were normal (32-100 ng/mL). Among men with localized prostate cancer, 18% were deficient, 50% were insufficient and 32% were normal. Among controls, 31% were deficient, 40% were insufficient and 29% were normal. Metastatic disease (P = 0.005) and season of blood sampling (winter/spring; P = 0.01) were associated with vitamin D deficiency in patients with prostate cancer, while age, race, performance status and body mass index were not. Vitamin D deficiency and insufficiency were common among men with prostate cancer and apparently normal controls in the western New York region.

Obstructed pancreaticojejunostomy partly explains exocrine insufficiency after pancreatic head resection.

Science.gov (United States)

Nordback, Isto; Parviainen, Mickael; Piironen, Anneli; Räty, Sari; Sand, Juhani

2007-02-01

The majority of patients with long-term survival after pancreatic head resection suffer from pancreatic exocrine insufficiency. The objective of this study was to investigate whether this is due to glandular malfunction or obstructed pancreaticojejunal anastomosis. Twenty-six patients (10 M, 16 F, mean age 61 years, range 34-81 years) were re-examined a median of 52 months (range 3-76 months) after pancreatic head resection and end-to-end invaginated pancreaticojejunostomy. Pancreatic exocrine function was measured by fecal elastase-1 assay. The size of the pancreatic remnant, glandular secretion and the flow through the anastomosis were analyzed with secretin-stimulated dynamic magnetic resonance pancreatography (D-MRP). All patients had pancreatic exocrine insufficiency, 24 (92%) of them having severe insufficiency. Eighteen patients (69%) reported moderate to severe diarrhea. Lowest fecal elastase-1 concentrations were associated with the initial diagnosis of chronic pancreatitis or ductal adenocarcinoma, suggesting preoperative primary or secondary chronic pancreatitis as important determinants. The size of the remnant gland did not correlate with the fecal elastase-1 concentrations. D-MRP failed in three patients. Severe glandular malfunctions were found in 7 (30%) of the 23 successful D-MRP examinations. The anastomosis was totally obstructed in 5 patients (22%) or partially obstructed in 6 (26%) but remained perfectly open in 5 patients (22%). The five patients with perfect anastomoses had the highest measured median fecal elastase-1 activity. Although late diarrhea and pancreatic exocrine insufficiency may be partly induced already by the disease treated with resection, at least half may be explained by obstructed anastomosis. To obtain better late functional results, improvements may be required in the surgical techniques.

Relative adrenal insufficiency in post-transplant lymphoproliferative disorder.

Directory of Open Access Journals (Sweden)

Cinclair R

2003-01-01

Full Text Available Post-transplant lymphoproliferative disorder is treated with rapid decrement of immunosuppressive therapy. This cannot be achieved with ease in patients on long-term glucocorticoid therapy, as chronically suppressed adrenal glands may not be capable of mounting adequate response to stress. A 52-year-old Caucasian male presented with fever, orthostatic hypotension, lymphadenopathy and hyponatraemia. Serum cortisol levels were within normal levels with a sub optimal response to stimulation by ACTH. Hyponatraemia and orthostasis responded poorly to fluid restriction, saline and salt repletion but corrected after increasing the steroid dose. The normal baseline cortisol levels represented a stimulated adrenal gland, however, the ACTH stimulation had inadequate response. This sub optimal stimulation and a good response to increased steroids suggest the presence of relative or occult adrenal insufficiency. Relative adrenal insufficiency must be considered in patients who have received prolonged glucocorticoid therapy and have symptoms such as hypotension and/or hyponatraemia.

Swiss electricity statistics 2005

International Nuclear Information System (INIS)

2006-01-01

This comprehensive report made by the Swiss Federal Office of Energy (SFOE) presents the statistics for 2005 on electricity production and usage in Switzerland for the year 2005. First of all, an overview of Switzerland's electricity supply in 2005 is presented. Details are noted of the proportions generated by different sources including nuclear, hydro-power, storage schemes and thermal power stations as well as energy transfer with neighbouring countries. A second chapter takes a look at the balance of imports and exports with illustrative flow diagrams along with tables for total figures from 1950 through to 2005. For the summer and winter periods, figures from 1995 to 2005 are presented. The third chapter examines the production of electricity in the various types of power stations and the developments over the years 1950 to 2005, whereby, for example, statistics on regional generation and power station type are looked at. The fourth chapter looks at electricity consumption in various sectors from 1983 to 2005 and compares the figures with international data. The fifth chapter looks at generation, consumption and loading on particular days and chapter six considers energy exchange with Switzerland's neighbours. Chapter seven takes a look at possibilities for extending generation facilities in the period up to 2012

Swiss electricity statistics 2008

International Nuclear Information System (INIS)

2009-06-01

This comprehensive report made by the Swiss Federal Office of Energy (SFOE) presents the statistics for 2008 on electricity production and usage in Switzerland for the year 2008. First of all, an overview of Switzerland's electricity supply in 2008 is presented. Details are noted of the proportions generated by different sources including nuclear, hydro-power, storage schemes and thermal power stations as well as energy transfer with neighbouring countries. A second chapter takes a look at the balance of imports and exports with illustrative flow diagrams along with tables for total figures from 1950 through to 2008. For the summer and winter periods, figures from 1995 to 2008 are presented. The third chapter examines the production of electricity in the various types of power stations and the developments over the years 1950 to 2008, whereby, for example, statistics on regional generation and power station type are looked at. The fourth chapter looks at electricity consumption in various sectors from 1984 to 2008 and compares the figures with international data. The fifth chapter looks at generation, consumption and loading on particular days and chapter six considers energy exchange with Switzerland's neighbours. Chapter seven takes a look at possibilities for extending generation facilities in the period up to 2015

Swiss electricity statistics 2006

International Nuclear Information System (INIS)

2007-01-01

This comprehensive report made by the Swiss Federal Office of Energy (SFOE) presents the statistics on electricity production and usage in Switzerland for the year 2006. First of all, an overview of Switzerland's electricity supply in 2006 is presented. Details are noted of the amounts generated by different sources including nuclear, hydro-power, storage schemes and thermal power stations as well as energy transfer with neighbouring countries. A second chapter takes a look at the balance of imports and exports with illustrative flow diagrams along with tables for total figures from 1950 through to 2006. For the summer and winter periods, figures from 1995 to 2006 are presented. The third chapter examines the production of electricity in the various types of power stations and the developments over the years 1950 to 2006, whereby, for example, statistics on regional generation and power station type are looked at. The fourth chapter looks at electricity consumption in various sectors from 1983 to 2006 and compares the figures with international data. The fifth chapter looks at generation, consumption and loading on particular, selected days and chapter six considers energy exchange with Switzerland's neighbours. Chapter seven takes a look at possibilities for extending generation facilities in the period up to 2013

Recurrence rates after abdominal and vaginal cerclages in women with cervical insufficiency

DEFF Research Database (Denmark)

Sneider, Kirstine; Christiansen, Ole Bjarne; Sundtoft, Iben Blaabjerg

2017-01-01

PURPOSE: To estimate the incidence of cervical insufficiency and compare recurrence rates of second trimester miscarriage/delivery in second and third pregnancies after prophylactic vaginal cerclage, abdominal cerclage, or no cerclage. METHODS: Retrospective chart review of a representative...... register-based sample of 621 women with a spontaneous second trimester miscarriage/delivery in the first pregnancy in Denmark (1997-2012). We used strict criteria for the diagnosis of cervical insufficiency. The outcome of subsequent pregnancies was described by treatment with prophylactic vaginal cerclage......, abdominal cerclage, or no prophylactic cerclage. Women were followed until June 2015. RESULTS: Of 621 women, 149 (24%) fulfilled the strict criteria of cervical insufficiency. Prophylactic treatment with abdominal cerclage (n = 20), vaginal cerclage (n = 59), and no prophylactic cerclage (n = 61) resulted...

IGESS: a statistical approach to integrating individual-level genotype data and summary statistics in genome-wide association studies.

Science.gov (United States)

Dai, Mingwei; Ming, Jingsi; Cai, Mingxuan; Liu, Jin; Yang, Can; Wan, Xiang; Xu, Zongben

2017-09-15

Results from genome-wide association studies (GWAS) suggest that a complex phenotype is often affected by many variants with small effects, known as 'polygenicity'. Tens of thousands of samples are often required to ensure statistical power of identifying these variants with small effects. However, it is often the case that a research group can only get approval for the access to individual-level genotype data with a limited sample size (e.g. a few hundreds or thousands). Meanwhile, summary statistics generated using single-variant-based analysis are becoming publicly available. The sample sizes associated with the summary statistics datasets are usually quite large. How to make the most efficient use of existing abundant data resources largely remains an open question. In this study, we propose a statistical approach, IGESS, to increasing statistical power of identifying risk variants and improving accuracy of risk prediction by i ntegrating individual level ge notype data and s ummary s tatistics. An efficient algorithm based on variational inference is developed to handle the genome-wide analysis. Through comprehensive simulation studies, we demonstrated the advantages of IGESS over the methods which take either individual-level data or summary statistics data as input. We applied IGESS to perform integrative analysis of Crohns Disease from WTCCC and summary statistics from other studies. IGESS was able to significantly increase the statistical power of identifying risk variants and improve the risk prediction accuracy from 63.2% ( ±0.4% ) to 69.4% ( ±0.1% ) using about 240 000 variants. The IGESS software is available at https://github.com/daviddaigithub/IGESS . zbxu@xjtu.edu.cn or xwan@comp.hkbu.edu.hk or eeyang@hkbu.edu.hk. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

VENOUS INSUFFICIENCY AND THROMBOEMBOLIC DISEASE IN BARIATRIC SURGERY PATIENTS

Directory of Open Access Journals (Sweden)

Bonno van BELLEN

2013-09-01

Full Text Available Context Morbid obesity is associated with various co-morbidities, including chronic venous insufficiency. Bariatric surgery is the only effective treatment for morbid obesity, but with potential risks and possible complications, including venous thromboembolism. Objective To determine the prevalence of clinical and ultrasonographic signs of chronic venous insufficiency in morbid obese patients in preparation for bariatric surgery and the incidence of post-operative venous thromboembolic disease. Methods Patients on work-up for bariatric surgery of Centro Terapêutico Especializado em Fígado (CETEFI and Pro-Gastro surgical teams of the Hospital Beneficência Portuguesa de São Paulo were included. The analysed data were pre-operative findings for venous insufficiency (CEAP - clinical, etiological, anatomical, physiopathologic - classification and venous ultrassonographic findings, type of surgery (open or laparoscopic, abdominal circumference, body mass index (BMI and post-operative ultrassonography search for venous insufficiency and deep venous thrombosis. Results Between March 2007 and December 2009, 95 patients candidates for bariatric surgery had clinical and duplex scan evaluation of the lower limbs venous system. Of the 95 patients, 53 were submitted to the surgical procedure. There was a predominance of women (77.9%, the average age was 38.5 years, average preoperative weight 124.6 kg and average BMI of 45.5 kg/m2. Regarding obesity, 16.8% were obese, and 83.1% were morbidly obese. In relation to the venous findings, 86.3% of the patients did fit CEAP classification less than 3 and 13.7% greater than or equal to 3. Among the post-operative complications, there were four cases of wound infection. Three patients developed post-operative distal venous thrombosis (7.5%, but no one had clinically manifested pulmonary embolism. Conclusion No relation between BMI, CEAP classification and venous ultrassonographic findings were found. Although

Insufficient free-time physical activity and occupational factors in Brazilian public school teachers

Directory of Open Access Journals (Sweden)

Douglas Fernando Dias

Full Text Available ABSTRACT OBJECTIVE To evaluate if perceived occupational factors are associated with insufficient free-time physical activity in Brazilian public school teachers. METHODS The relationship between insufficient physical activity (< 150 minutes/week and variables related to work was analyzed in 978 elementary and high school teachers calculating the prevalence ratio (PR and 95% confidence interval (95%CI in Poisson regression models, adjusted for sociodemographic and health variables. RESULTS The prevalence of insufficient physical activity was 71.9%, and this condition was associated independently with the perception of bad or regular balance between personal and professional life (PR = 1.09; 95%CI 1.01–1.18, perception that standing time affects the work (PR = 1.16; 95%CI 1.01–1.34, low or very low perception of current ability for the physical requirements of work (PR = 1.21; 95%CI 1.08–1.35, and temporary employment contract (PR = 1.13; 95%CI 1.03–1.25. The teaching of physical education was associated with lower prevalence of insufficient physical activity (PR = 0.78; 95%CI 0.64–0.95. CONCLUSIONS The perception of adverse working conditions is associated with increased prevalence of insufficient physical activity in teachers and should be considered for the promotion of physical activity in this population.

Power reactors operational diagnosis

International Nuclear Information System (INIS)

Dach, K.; Pecinka, L.

1976-01-01

The definition of reactor operational diagnostics is presented and the fundamental trends of research are determined. The possible sources of power reactor malfunctions, the methods of defect detection, the data evaluation and the analysis of the results are discussed in detail. In view of scarcity of a theoretical basis and of insufficient in-core instrumentation, operational diagnostics cannot be as yet incorporated in a computer-aided reactor control system. (author)

Energy statistics. France

International Nuclear Information System (INIS)

2002-10-01

This document summarizes in a series of tables the energy statistical data for France: consumption since 1973; energy supplies (production, imports, exports, stocks) and uses (refining, power production, internal uses, sectoral consumption) for coal, petroleum, gas, electricity, and renewable energy sources; national production and consumption of primary energy; final consumption per sector and per energy source; general indicators (energy bill, US$ change rate, prices, energy independence, internal gross product); projections. Details (resources, uses, prices, imports, internal consumption) are given separately for petroleum, natural gas, electric power and solid mineral fuels. (J.S.)

Inferring Demographic History Using Two-Locus Statistics.

Science.gov (United States)

Ragsdale, Aaron P; Gutenkunst, Ryan N

2017-06-01

Population demographic history may be learned from contemporary genetic variation data. Methods based on aggregating the statistics of many single loci into an allele frequency spectrum (AFS) have proven powerful, but such methods ignore potentially informative patterns of linkage disequilibrium (LD) between neighboring loci. To leverage such patterns, we developed a composite-likelihood framework for inferring demographic history from aggregated statistics of pairs of loci. Using this framework, we show that two-locus statistics are more sensitive to demographic history than single-locus statistics such as the AFS. In particular, two-locus statistics escape the notorious confounding of depth and duration of a bottleneck, and they provide a means to estimate effective population size based on the recombination rather than mutation rate. We applied our approach to a Zambian population of Drosophila melanogaster Notably, using both single- and two-locus statistics, we inferred a substantially lower ancestral effective population size than previous works and did not infer a bottleneck history. Together, our results demonstrate the broad potential for two-locus statistics to enable powerful population genetic inference. Copyright © 2017 by the Genetics Society of America.

News about the genetics of congenital primary adrenal insufficiency.

Science.gov (United States)

Roucher-Boulez, Florence; Mallet-Motak, Delphine; Tardy-Guidollet, Véronique; Menassa, Rita; Goursaud, Claire; Plotton, Ingrid; Morel, Yves

2018-04-13

Primary adrenal insufficiency (PAI) is characterized by impaired production of steroid hormones due to an adrenal cortex defect. This condition incurs a risk of acute insufficiency which may be life-threatening. Today, 80% of pediatric forms of PAI have a genetic origin but 5% have no clear genetic support. Recently discovered mutations in genes relating to oxidative stress have opened the way to research on genes unrelated to the adrenal gland. Identification of causal mutations in a gene responsible for PAI allows genetic counseling, guidance of follow-up and prevention of complications. This is particularly true for stress oxidative anomalies, as extra-adrenal manifestations may occur due to the sensitivity to oxidative stress of other organs such as the heart, thyroid, liver, kidney and pancreas. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Population-Level Incidence and Predictors of Surgically Induced Diabetes and Exocrine Insufficiency after Partial Pancreatic Resection.

Science.gov (United States)

Elliott, Irmina A; Epelboym, Irene; Winner, Megan; Allendorf, John D; Haigh, Philip I

2017-01-01

Endocrine and exocrine insufficiency after partial pancreatectomy affect quality of life, cardiovascular health, and nutritional status. However, their incidence and predictors are unknown. To identify the incidence and predictors of new-onset diabetes and exocrine insufficiency after partial pancreatectomy. We retrospectively reviewed 1165 cases of partial pancreatectomy, performed from 1998 to 2010, from a large population-based database. Incidence of new onset diabetes and exocrine insufficiency RESULTS: Of 1165 patients undergoing partial pancreatectomy, 41.8% had preexisting diabetes. In the remaining 678 patients, at a median 3.6 months, diabetes developed in 274 (40.4%) and pancreatic insufficiency developed in 235 (34.7%) patients. Independent predictors of new-onset diabetes were higher Charlson Comorbidity Index (CCI; hazard ratio [HR] = 1.62 for CCI of 1, p = 0.02; HR = 1.95 for CCI ≥ 2, p pancreatitis (HR = 1.51, p = 0.03). There was no difference in diabetes after Whipple procedure vs distal pancreatic resections, or malignant vs benign pathologic findings. Independent predictors of exocrine insufficiency were female sex (HR = 1.32, p = 0.002) and higher CCI (HR = 1.85 for CCI of 1, p insufficiency (HR = 0.35, p endocrine and exocrine insufficiency were 40% and 35%, respectively. These data are critical for informing patients' and physicians' expectations.

Premature ovarian insufficiency in young girls: repercussions on uterine volume and bone mineral density.

Science.gov (United States)

Bakhsh, Hanadi; Dei, Metella; Bucciantini, Sandra; Balzi, Daniela; Bruni, Vincenzina

2015-01-01

To evaluate biological differences among young subjects with premature ovarian insufficiency (POI) commencing at different stages of life. Retrospective observational study. Careggi University Hospital Participants: One hundred sixty-two females aged between 15 and 29 years with premature ovarian insufficiency. Data were collected as a retrospective chart review of baseline evaluation at diagnosis of premature ovarian insufficiency (POI). About 162 participants were divided into four groups based on gynecological age. Two primary outcome variables (uterine development and bone mineral density (BMD)) were analyzed in terms of differences among groups and in a multivariate logistic regression analysis. Uterine development was clearly jeopardized when estrogen insufficiency started at a very young age. Total body BMD showed significant differences among the four groups studied, clearly corresponding to the duration of ovarian function. Data were discussed in relation to the choice of hormone replacement therapy regimens.

Statistical analysis with Excel for dummies

CERN Document Server

Schmuller, Joseph

2013-01-01

Take the mystery out of statistical terms and put Excel to work! If you need to create and interpret statistics in business or classroom settings, this easy-to-use guide is just what you need. It shows you how to use Excel's powerful tools for statistical analysis, even if you've never taken a course in statistics. Learn the meaning of terms like mean and median, margin of error, standard deviation, and permutations, and discover how to interpret the statistics of everyday life. You'll learn to use Excel formulas, charts, PivotTables, and other tools to make sense of everything fro

Wind energy statistics

International Nuclear Information System (INIS)

Holttinen, H.; Tammelin, B.; Hyvoenen, R.

1997-01-01

The recording, analyzing and publishing of statistics of wind energy production has been reorganized in cooperation of VTT Energy, Finnish Meteorological (FMI Energy) and Finnish Wind Energy Association (STY) and supported by the Ministry of Trade and Industry (KTM). VTT Energy has developed a database that contains both monthly data and information on the wind turbines, sites and operators involved. The monthly production figures together with component failure statistics are collected from the operators by VTT Energy, who produces the final wind energy statistics to be published in Tuulensilmae and reported to energy statistics in Finland and abroad (Statistics Finland, Eurostat, IEA). To be able to verify the annual and monthly wind energy potential with average wind energy climate a production index in adopted. The index gives the expected wind energy production at various areas in Finland calculated using real wind speed observations, air density and a power curve for a typical 500 kW-wind turbine. FMI Energy has produced the average figures for four weather stations using the data from 1985-1996, and produces the monthly figures. (orig.)

Altered Cyclosporine Absorption in a Patient with Ulcerative Colitis, Sclerosing Cholangitis and Pancreatic Insufficiency

Directory of Open Access Journals (Sweden)

Mark G Swain

1991-01-01

Full Text Available Pancreatic insufficiency leading to altered cyclosporine absorption is reported in a 37-year-old man with ulcerative colitis and sclerosing cholangitis. Asymptomatic chronic pancreatitis occurs frequently in patients with ulcerative colitis, and even more commonly when there is coexistent sclerosing cholangitis. However, pancreatic insufficiency has been documented in only one patient previously with ulcerative colitis and sclerosing cholangitis. Pancreatic function testing can help to identify the complex etiology of malabsorption in these patients and is recommended in patients when liver transplantation is contemplated, as pancreatic insufficiency may alter the absorption of cyclosporine.

Quantitative assessment of bone marrow attenuation values at MDCT: An objective tool for the detection of bone bruise related to occult sacral insufficiency fractures

Energy Technology Data Exchange (ETDEWEB)

Henes, F.O.; Groth, M.; Bley, T.A.; Regier, M.; Ittrich, H.; Adam, G.; Bannas, P. [University Medical Center Hamburg-Eppendorf, Department of Diagnostic and Interventional Radiology, Hamburg (Germany); Nuechtern, J.V. [University Medical Center Hamburg-Eppendorf, Department of Trauma, Hand and Reconstructive Surgery, Hamburg (Germany); Treszl, A. [University Medical Center Hamburg-Eppendorf, Center for Experimental Medicine, Department of Medical Biometry and Epidemiology, Hamburg (Germany)

2012-10-15

To prove the feasibility of using Hounsfield attenuation values at MDCT to detect bone bruises related to sacral insufficiency fractures. Twenty-two patients with acute sacrum trauma and no fracture findings at MDCT were included in our prospective study. Two observers independently reviewed CTs regarding visual signs of bone bruises in 132 defined regions of the sacral alae. Interobserver agreement was tested by {kappa} statistics. Subsequently, HU values were obtained in the same regions, and attenuation differences between the two sides were calculated. Validity and reliability were assessed by intraclass correlation coefficient and Bland-Altman analysis. HU differences were subjected to ROC curve analysis to determine sensitivity, specificity, PPV and NPV. MRI served as standard reference. MRI revealed 19 regions with bone bruises and associated sacral insufficiency fractures. HU measurements demonstrated good validity and reliability (r = 0.989). ROC curve analysis exhibited an ideal cutoff value of 35.7 HU density difference between affected and non-affected regions. Visual evaluation revealed moderate agreement ({kappa} = 0.48); diagnostic accuracy was inferior to objective evaluation. Assessment of differences in bone marrow density by HU measurements is an objective and reliable tool for detection of bone bruises associated with occult sacral insufficiency fractures. (orig.)

People's awareness toward power generation choices. Two and a half years after the Fukushima Daiichi Nuclear Power Plant accident

International Nuclear Information System (INIS)

Kitada, Atsuko

2014-01-01

INSS has conducted continuous opinion polls about nuclear power generation (NPG) sixteen times from 1993 to October 2013. The latest survey is the fourth one since the Fukushima Daiichi Nuclear Power Plant accident and comes two-and-a-half years after the accident. In this study those survey data were analyzed, and the results were as follows. (1) The percent of persons considering the use of NPG as inevitable has dropped a little, but 53% affirm NPG is necessary. (2) It was suggested that the problems such as the leakage of radioactive water at Fukushima Daiichi had a negative impact on the opinion toward use of NPG. (3) Because of the reduction of supply capacity due to long-term suspension of nuclear power plant operations, electric power was insufficient in summer and winter, but people were able to overcome the supply shortage by continuing their power-saving activities. The percentage of people who thought the electric power was insufficient did not increase in particular. The percent who thought a reduction of the NPG should cause the power supply to be unstable, has decreased gradually. (4) Even though five months before the survey was taken there was a nearly 10% electric rate hike to cover increased fuel costs due to having thermal power replace NPG, a lot of people did not think their own electric bill had increased from last year. This suggested that people do not pay much attention to their own electric bills after a rate hike. (5) Negative effects of long-term suspension of NPG have not been recognized and the presence of NPG has declined, and people's support for the policy target of 'zero nuclear power by the 2030s,' has not been reduced, even though the government has changed its goal. (author)

Is there any correlation between vitamin D insufficiency and diabetic retinopathy?

Institute of Scientific and Technical Information of China (English)

Shokoufeh; Bonakdaran; Nasser; Shoeibi

2015-01-01

AIM: To determine a relation between vitamin D level,which is an inhibitor of angiogenesis, and diabetic retinopathy and its risk factorsMETHODS: In a clinic-based cross sectional study two hundred and thirty-five type 2 diabetic patients older than 20 y were selected. Patients were classified according to ophthalmologic examination as following:no diabetic retinopathy(NDR)(n =153), non-proliferative diabetic retinopathy(NPDR)(n =64) and proliferative diabetic retinopathy(PDR)(n =18). Study subjects were tested for fasting blood glucose, glycated hemoglobin A1C(Hb A1C), lipid profile, microalbuminuria, Hs CRP,IGF1, insulin(in patients without history of insulin taking)and 25 hydroxy vitamin D [25(OH) D] levels. Vitamin D insufficiency was defined according to 25(OH) D level less than 30 ng/m L. The relationship between diabetic retinopathy and serum 25(OH) D insufficiency was evaluated.RESULTS: The prevalence of diabetic retinopathy was34.8% in our patients. Long duration of diabetes,hypertension, poor glycemic control, diabetic nephropathy, hyperinsulinemia and insulin resistance were risk factors for diabetic retinopathy but 25(OH) D level was not significant different between NDR, NPDR and PDR groups. Correlation between 25(OH) D level and other known risk factors of diabetic retinopathy was not significant.CONCLUSION: This study did not find any association between diabetic retinopathy and its severity and vitamin D insufficiency. Vitamin D insufficiency is not related to risk factors of diabetic retinopathy.

Paraoxonase activity in patients with chronic renal failure and hepatic insufficiency

International Nuclear Information System (INIS)

Jamal, S.; Ishaq, M.; Hussain, S.M.W.; Alam, J.A.; Hussain, S.

2010-01-01

Paraoxonase (PON), a high density lipoprotein (HDL) associated enzyme, is believed to protect against the oxidation of low density lipoprotein (LDL) and hence affects the risk of vascular disease. PON is sensitive to oxidants and is inactivated by oxidized lipids, and thus it can be postulated that increased oxidative stress may decrease plasma PON activity in patients with chronic renal failure (CRF) and hepatic insufficiency (HI). Moreover, in CRF and HI patients, in contrast to normal individuals, higher levels of plasma biochemical parameters and liver enzymes had an inverse correlation with PON activity. In this study we aimed to investigate PON activity, total bilirubin, creatinine, urea and liver enzymes alanine aminotransferase and alkaline phosphatase that are the index of renal and hepatic insufficiency. We have analyzed plasma from pre-dialysis patients and compared the results with the normal individuals. We observed a positive association of PON activity with that of the disease state i.e. the activity of this enzyme was significantly lower in the patients (p < 0.001). Furthermore, the indicators of renal and hepatic insufficiency were significantly elevated as compared to the normal subjects. Based on our results we conclude that in CRF and HI, in contrast to normal individuals, higher levels of plasma biochemical parameters and liver enzymes had inverse correlation with PON activity. Collectively, these findings may add details to the understanding of the role that PON plays in chronic renal failure and hepatic insufficiency. (author)

Combined metabolomic and correlation networks analyses reveal fumarase insufficiency altered amino acid metabolism.

Science.gov (United States)

Hou, Entai; Li, Xian; Liu, Zerong; Zhang, Fuchang; Tian, Zhongmin

2018-04-01

Fumarase catalyzes the interconversion of fumarate and l-malate in the tricarboxylic acid cycle. Fumarase insufficiencies were associated with increased levels of fumarate, decreased levels of malate and exacerbated salt-induced hypertension. To gain insights into the metabolism profiles induced by fumarase insufficiency and identify key regulatory metabolites, we applied a GC-MS based metabolomics platform coupled with a network approach to analyze fumarase insufficient human umbilical vein endothelial cells (HUVEC) and negative controls. A total of 24 altered metabolites involved in seven metabolic pathways were identified as significantly altered, and enriched for the biological module of amino acids metabolism. In addition, Pearson correlation network analysis revealed that fumaric acid, l-malic acid, l-aspartic acid, glycine and l-glutamic acid were hub metabolites according to Pagerank based on their three centrality indices. Alanine aminotransferase and glutamate dehydrogenase activities increased significantly in fumarase deficiency HUVEC. These results confirmed that fumarase insufficiency altered amino acid metabolism. The combination of metabolomics and network methods would provide another perspective on expounding the molecular mechanism at metabolomics level. Copyright © 2017 John Wiley & Sons, Ltd.

Response of geomorphic and geological processes to insufficient ...

Indian Academy of Sciences (India)

Depositional models have been constructed for each segment: a constant shelf break model with insufficient sediment supply in the east, and a migration shelf break model with plenty sediment supply in the west. This case study contributes to the understanding of the upper slope sedimentary process and stratigraphic style ...

Prevalence of insufficient, borderline, and optimal hours of sleep among high school students - United States, 2007.

Science.gov (United States)

Eaton, Danice K; McKnight-Eily, Lela R; Lowry, Richard; Perry, Geraldine S; Presley-Cantrell, Letitia; Croft, Janet B

2010-04-01

We describe the prevalence of insufficient, borderline, and optimal sleep hours among U.S. high school students on an average school night. Most students (68.9%) reported insufficient sleep, whereas few (7.6%) reported optimal sleep. The prevalence of insufficient sleep was highest among female and black students, and students in grades 11 and 12. Published by Elsevier Inc.

Subchondral insufficiency fracture of the femoral head in a patient with alkaptonuria

Energy Technology Data Exchange (ETDEWEB)

Hamada, Takahiro; Shida, Jun-ichi; Inokuchi, Akihiko; Arizono, Takeshi [Kyushu Central Hospital, Department of Orthopaedic Surgery, Fukuoka-city (Japan); Yamamoto, Takuaki [Kyushu University, Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Fukuoka-city (Japan)

2014-06-15

We report a patient with alkaptonuria accompanied by bilateral rapidly destructive arthrosis of the hip. The destruction of the left hip joint with its severe functional impairment necessitated total hip arthroplasty (THA). The outcome was satisfactory. Both magnetic resonance imaging (MRI) and pathologic findings were compatible with a subchondral insufficiency fracture. A year and half later, during a follow-up visit, the patient complained of right coxalgia. Radiography showed that the right femoral head had already disappeared, requiring THA of the right hip. Although there have been a few reports of rapid destructive hip osteoarthritis associated with ochronotic arthropathy, the pathogenesis of the destructive change is not clear. Subchondral insufficiency fracture was diagnosed on MR imaging and pathologically confirmed in our patient with alkaptonuria, suggesting that subchondral insufficiency fracture is one of the causes of ochronotic hip destruction. (orig.)

Subchondral insufficiency fracture of the femoral head in a patient with alkaptonuria

International Nuclear Information System (INIS)

Hamada, Takahiro; Shida, Jun-ichi; Inokuchi, Akihiko; Arizono, Takeshi; Yamamoto, Takuaki

2014-01-01

We report a patient with alkaptonuria accompanied by bilateral rapidly destructive arthrosis of the hip. The destruction of the left hip joint with its severe functional impairment necessitated total hip arthroplasty (THA). The outcome was satisfactory. Both magnetic resonance imaging (MRI) and pathologic findings were compatible with a subchondral insufficiency fracture. A year and half later, during a follow-up visit, the patient complained of right coxalgia. Radiography showed that the right femoral head had already disappeared, requiring THA of the right hip. Although there have been a few reports of rapid destructive hip osteoarthritis associated with ochronotic arthropathy, the pathogenesis of the destructive change is not clear. Subchondral insufficiency fracture was diagnosed on MR imaging and pathologically confirmed in our patient with alkaptonuria, suggesting that subchondral insufficiency fracture is one of the causes of ochronotic hip destruction. (orig.)

Subchondral insufficiency fracture of the femoral head in a patient with alkaptonuria.

Science.gov (United States)

Hamada, Takahiro; Yamamoto, Takuaki; Shida, Jun-ichi; Inokuchi, Akihiko; Arizono, Takeshi

2014-06-01

We report a patient with alkaptonuria accompanied by bilateral rapidly destructive arthrosis of the hip. The destruction of the left hip joint with its severe functional impairment necessitated total hip arthroplasty (THA). The outcome was satisfactory. Both magnetic resonance imaging (MRI) and pathologic findings were compatible with a subchondral insufficiency fracture. A year and half later, during a follow-up visit, the patient complained of right coxalgia. Radiography showed that the right femoral head had already disappeared, requiring THA of the right hip. Although there have been a few reports of rapid destructive hip osteoarthritis associated with ochronotic arthropathy, the pathogenesis of the destructive change is not clear. Subchondral insufficiency fracture was diagnosed on MR imaging and pathologically confirmed in our patient with alkaptonuria, suggesting that subchondral insufficiency fracture is one of the causes of ochronotic hip destruction.

Statistical properties of reactor antineutrinos

CERN Document Server

Rusov, V D; Tarasov, V O; Shaaban, Y

2002-01-01

Based on the properties of the cascade statistics of reactor antineutrinos, the efficient method of searching for neutrino oscillations is offered. The determination of physical parameters of this statistics, i.e. the average number of fissions and the overage number of antineutrinos per fission, requires no a priori knowledge of the geometry and characteristics of the detector, the reactor power, and composition of nuclear fuel.

Study of developing a database of energy statistics

Energy Technology Data Exchange (ETDEWEB)

Park, T.S. [Korea Energy Economics Institute, Euiwang (Korea, Republic of)

1997-08-01

An integrated energy database should be prepared in advance for managing energy statistics comprehensively. However, since much manpower and budget is required for developing an integrated energy database, it is difficult to establish a database within a short period of time. Therefore, this study sets the purpose in drawing methods to analyze existing statistical data lists and to consolidate insufficient data as first stage work for the energy database, and at the same time, in analyzing general concepts and the data structure of the database. I also studied the data content and items of energy databases in operation in international energy-related organizations such as IEA, APEC, Japan, and the USA as overseas cases as well as domestic conditions in energy databases, and the hardware operating systems of Japanese databases. I analyzed the making-out system of Korean energy databases, discussed the KEDB system which is representative of total energy databases, and present design concepts for new energy databases. In addition, I present the establishment directions and their contents of future Korean energy databases, data contents that should be collected by supply and demand statistics, and the establishment of data collection organization, etc. by analyzing the Korean energy statistical data and comparing them with the system of OECD/IEA. 26 refs., 15 figs., 11 tabs.

Inflammatory manifestations of experimental lymphatic insufficiency.

Directory of Open Access Journals (Sweden)

Raymond Tabibiazar

2006-07-01

Full Text Available BACKGROUND: Sustained lymph stagnation engenders a pathological response that is complex and not well characterized. Tissue inflammation in lymphedema may reflect either an active or passive consequence of impaired immune traffic. METHODS AND FINDINGS: We studied an experimental model of acute post-surgical lymphedema in the tails of female hairless, immunocompetent SKH-1 mice. We performed in vivo imaging of impaired immune traffic in experimental, murine acquired lymphatic insufficiency. We demonstrated impaired mobilization of immunocompetent cells from the lymphedematous region. These findings correlated with histopathological alterations and large-scale transcriptional profiling results. We found intense inflammatory changes in the dermis and the subdermis. The molecular pattern in the RNA extracted from the whole tissue was dominated by the upregulation of genes related to acute inflammation, immune response, complement activation, wound healing, fibrosis, and oxidative stress response. CONCLUSIONS: We have characterized a mouse model of acute, acquired lymphedema using in vivo functional imaging and histopathological correlation. The model closely simulates the volume response, histopathology, and lymphoscintigraphic characteristics of human acquired lymphedema, and the response is accompanied by an increase in the number and size of microlymphatic structures in the lymphedematous cutaneous tissues. Molecular characterization through clustering of genes with known functions provides insights into processes and signaling pathways that compose the acute tissue response to lymph stagnation. Further study of genes identified through this effort will continue to elucidate the molecular mechanisms and lead to potential therapeutic strategies for lymphatic vascular insufficiency.

Higher visceral fat area increases the risk of vitamin D insufficiency and deficiency in Chinese adults.

Science.gov (United States)

Zhang, Meilin; Li, Ping; Zhu, Yufeng; Chang, Hong; Wang, Xuan; Liu, Weiqiao; Zhang, Yuwen; Huang, Guowei

2015-01-01

Visceral fat area (VFA), a novel sex-specific index for visceral fat obesity (VFO) might play a major role in the development of vitamin D deficiency. However, the association between VFA and vitamin D insufficiency and deficiency in Chinese population is less clear. The aim of this study was to explore the population-level association between VFA and vitamin D insufficiency and deficiency among Chinese men and women. This cross-sectional study involved 1105 adults aged 20-70 years living in Tianjin who were randomly selected and medically examined. All subjects underwent the bioelectrical impedance analysis (BIA) method to estimate the VFA. Serum 25-hydroxyvitamin D3 (25(OH) D3) level was assayed by the high-performance liquid chromatography (HPLC) method and defined insufficiency and deficiency following recommended cutoffs. The association between VFA and vitamin D insufficiency and deficiency was estimated using binary regression analysis. The total prevalence of vitamin D insufficiency (25(OH) D3: 20-29 μg/L) and deficiency (25(OH) D3  0.05). Moreover, increased VFA was observed to be associated with higher vitamin D insufficiency or deficiency risk with a positive dose-response trend (P for trend convenience surrogate marker for visceral adipose measurement and could be used in identifying the risk of vitamin D insufficiency and deficiency in routine health examination.

Rectal hydrocortisone during vomiting in children with adrenal insufficiency.

Science.gov (United States)

Ní Chróinín, M; Fallon, M; Kenny, D; Moriarty, S; Hoey, H; Costigan, C

2003-01-01

To evaluate rectal hydrocortisone as an emergency glucocorticoid replacement therapy in adrenal insufficient children. A parental questionnaire evaluated preferred treatment, problems or benefits of i.m. and rectal hydrocortisone, frequency and indications for administration and who administered treatment. Admissions of children with adrenal insufficiency were monitored. There were 39/52 families who responded to the questionnaire. 93% (26/28) preferred rectal hydrocortisone. Parents or children who previously received emergency treatment from a doctor now self-administered rectal hydrocortisone. The cost of suppositories and i.m. hydrocortisone is similar; however, storage of suppositories was inconvenient. One girl presented with pneumonia and collapse despite rectal hydrocortisone and a hydrocortisone level at admission of >2000 nmol/l with normal electrolytes. Rectal hydrocortisone is an acceptable and safe emergency therapy. We still advise i.m. hydrocortisone if rectal administration is not possible or with suppository extrusion.

Superselective transcatheter renal arterial embolization for acute renal bleeding in patients with renal insufficiency: its clinical efficacy and safety

International Nuclear Information System (INIS)

Hu Tingyang; Zhou Bing; Yu Wenqiang; Luo Zuyan; Mao Yingmin; Chen Fanghong; Li Bo; Yuan Jianhua

2010-01-01

Objective: To discuss the clinical efficacy and complications of super selective renal arterial embolization in treating acute renal arterial bleeding in patients with renal insufficiency, and to evaluate the influence of the treatment on the renal function. Methods: During the period of January 2000 December 2009, super selective renal arterial embolization was performed in our institution for acute renal bleeding in 13 patients with renal insufficiency. The complete clinical and imaging materials of all patients were properly collected. The clinical effectiveness, the renal function, the extent of embolization and the complications were observed and the relationship between each other was analyzed. Results: The embolization procedure was successfully completed in all patients with a technical success rate of 100%. The mean embolized territory was 22% of a single kidney. Three days after the procedure, the hemoglobin level, hematocrit, blood pressure and heart rate were considerably improved in all patients. Compared to the corresponding preoperative data, all the differences were statistically significant (P 0.05), while the blood urea nitrogen was markedly decreased (P=0.011). Post embolization syndrome occurred in 5 patients and progressive aggravation of the renal function was observed in one patient, who had to receive hemodialysis finally. The embolized territory in patients occurring complications was larger than that in patients without occurring complications (U=1.500, P=0.006). Conclusion: Super selective renal arterial embolization is an effective and safe treatment for acute renal arterial bleeding in patients with renal insufficiency, the therapy will not significantly worsen the renal function. Appropriate and reasonable extent of embolization, as small as possible, is the key point for reducing the complications. (authors)

Lethal Progressive Thoracic Insufficiency in a Neonate Due to Jarcho Levin Syndrome

Science.gov (United States)

Bhutia, Euden; Maria, Arti; Verma, Arushi; Sethi, Sidharth Kumar

2014-01-01

A rare case of Jarcho Levin syndrome (JLS) presenting as a lethal progressive respiratory insufficiency in early neonatal period is reported. The neonate had classical features of this syndrome including vertebral segmentation defects, typical costo-vertebral fusion defects and scoliosis resulting in small thoracic volume and limited chest expansion; all consistent with a clinical diagnosis of JLS with thoracic insufficiency. In addition, our case had a rare association of dextrocardia and acyanotic congenital heart disease. PMID:24741543

Joint probability of statistical success of multiple phase III trials.

Science.gov (United States)

Zhang, Jianliang; Zhang, Jenny J

2013-01-01

In drug development, after completion of phase II proof-of-concept trials, the sponsor needs to make a go/no-go decision to start expensive phase III trials. The probability of statistical success (PoSS) of the phase III trials based on data from earlier studies is an important factor in that decision-making process. Instead of statistical power, the predictive power of a phase III trial, which takes into account the uncertainty in the estimation of treatment effect from earlier studies, has been proposed to evaluate the PoSS of a single trial. However, regulatory authorities generally require statistical significance in two (or more) trials for marketing licensure. We show that the predictive statistics of two future trials are statistically correlated through use of the common observed data from earlier studies. Thus, the joint predictive power should not be evaluated as a simplistic product of the predictive powers of the individual trials. We develop the relevant formulae for the appropriate evaluation of the joint predictive power and provide numerical examples. Our methodology is further extended to the more complex phase III development scenario comprising more than two (K > 2) trials, that is, the evaluation of the PoSS of at least k₀ (k₀≤ K) trials from a program of K total trials. Copyright © 2013 John Wiley & Sons, Ltd.

Gastroenterological surgery for patients with chronic respiratory insufficiency.

Science.gov (United States)

Shimada, M; Kano, T; Matsuzaki, Y; Miyazaki, N; Ninomiya, K

1998-01-01

The aim of this study was to clarify the surgical indications for patients with chronic respiratory insufficiency. Fourteen patients with chronic respiratory insufficiency who underwent abdominal surgical procedures, were retrospectively studied. The surgical indications were carefully determined based primarily on the performance status (PS) of each patient and cardiopulmonary function tests. A PS of equal to or less than 3, which meant the patient's status required bed rest > 50% of the time, and the need for assistance in performing normal activities were all factors considered for surgical indications. During the period studied, two patients were excluded from the surgical indications due to the fact that one was at a terminal stage of pulmonary disease and was completely bedridden (PS = 4), while the other demonstrated active pneumonia with a considerable amount of purulent sputa. Regarding the pulmonary function tests for patients who underwent surgery, the lowest limits of those examinations were as follows: 810 ml of vital capacity (VC), 23.8% of predicted VC, 610 ml of forced expiratory volume in one second (FEV1.0), 38.6% of predicted FEV1.0, 50.5 mmHg of PaO2 while inhaling 4 liters of oxygen and 73.8 mmHg of PaCO2. No surgery related mortality or hospital death within 30 days after operation was observed. Only two patients had cardiopulmonary complications (consisting of pulmonary edema with atrial fibrillation in one patient, and acute myocardial infarction in another patient). However, neither pneumonia, prolonged ventilatory support for more than 2 days, nor the need for a tracheostomy after surgery was observed. Gastroenterological surgery is thus considered to be indicated even for patients with chronic respiratory insufficiency, as long as the PS can be maintained (PS of equal to or less than 3) and no active pneumonia with a considerable amount of purulent sputa is present.

Traumatic tricuspid valve insufficiency. Experience in thirteen patients.

Science.gov (United States)

van Son, J A; Danielson, G K; Schaff, H V; Miller, F A

1994-11-01

From 1964 through June 1993, thirteen patients with traumatic tricuspid insufficiency were treated surgically; all were male, and the ages ranged from 17 to 64 years (median 39 years). The condition was associated with blunt chest trauma in all patients: motor vehicle accidents in twelve and an explosion of a tank of compressed air in one. The median duration between trauma and operation was 17 years (range 1 month to 37 years). Preoperatively, six patients were in sinus rhythm and seven were in atrial fibrillation. At operation, the right ventricular function appeared moderately to severely depressed in twelve patients. In twelve patients, the anterior leaflet was flail because of chordal rupture (n = 9), rupture of anterior papillary muscle (n = 3), or tear in the anterior leaflet (n = 1). In one patient, the septal leaflet was missing and in another it was retracted and adherent to the ventricular septum. In five patients the tricuspid valve was repaired and in eight it was replaced. In seven patients in the latter group, the chordae, papillary muscles, and/or tricuspid valve leaflet(s) were found to be in a contracted and atrophic state, precluding repair. No early or late deaths occurred. At follow-up extending to 26 years (median 12 years), 12 patients are in New York Heart Association class I and one patient is in class II. Nine patients were in sinus rhythm and four were in atrial fibrillation. Although our experience indicates that good functional results can still be achieved many years after the onset of traumatic tricuspid valve insufficiency, earlier diagnosis and surgical treatment should increase the feasibility of tricuspid valve insufficiency, earlier diagnosis and surgical treatment should increase the feasibility of tricuspid valve repair, prevent progressive deterioration of right ventricular function, and increase the possibility of maintaining late sinus rhythm in a greater number of patients.

Hydrocortisone dose in adrenal insufficiency : Balancing harms and benefits

NARCIS (Netherlands)

Werumeus Buning, Jorien

2017-01-01

Patients with secondary adrenal insufficiency do not produce cortisol and are therefore treated with hydrocortisone tablets. The optimal substitution dose for hydrocortisone is unknown. We therefore performed this study, in which two different doses of hydrocortisone and its effect on cognition

Association between vitamin D insufficiency and elevated serum uric acid among middle-aged and elderly Chinese Han women.

Directory of Open Access Journals (Sweden)

Hao Peng

Full Text Available BACKGROUND: Association between vitamin D insufficiency and hyperuricemia has not been reported so far. We aimed to study the association of vitamin D insufficiency with elevated serum uric acid among middle-aged and elderly Chinese Han women. METHODS: We collected data from participants residing in Jinchang district of Suzhou from January to May, 2010. Serum uric acid, 25-hydroxy vitamin D and other traditional biomarkers including fasting plasma glucose and blood lipids were determined in 1726 women aged above 30 years. Association between vitamin D insufficiency and elevated uric acid was analyzed in premenopausal and postmenopausal women, respectively. RESULTS: Among postmenopausal women, 25-hydroxy vitamin D level of participants with elevated uric acid was lower than that of those with normal uric acid (median [interquartile range]: 35[28-57] vs 40[32-58], µg/L; P = 0.006. Elevated uric acid was more prevalent in participants with vitamin D insufficiency compared to those without vitamin D insufficiency (16.50% vs 8.08%; P<0.001. Association between vitamin D insufficiency and elevated uric acid was not significant among premenopausal women. However, participants with vitamin D insufficiency were more likely to have elevated uric acid compared with those without vitamin D insufficiency among postmenopausal women (OR, 95% CI: 2.38, 1.47-3.87. Moreover, after excluding individuals with diabetes and/or hypertension, the association of vitamin D insufficiency with elevated uric acid was still significant (OR, 95% CI: 2.48, 1.17-5.44. CONCLUSIONS: Vitamin D insufficiency was significantly associated with elevated uric acid among postmenopausal Chinese Han women. This study suggested that a clinical trial should be conducted to confirm the association of vitamin D insufficiency with hyperuricemia.

Subchondral insufficiency fracture of the knee: a non-traumatic injury with prolonged recovery time.

Science.gov (United States)

Gourlay, Margaret L; Renner, Jordan B; Spang, Jeffrey T; Rubin, Janet E

2015-06-08

Subchondral insufficiency fractures are non-traumatic fractures that occur immediately below the cartilage of a joint. Although low bone density may be present concurrently, it is not the underlying cause of subchondral insufficiency fractures in the majority of patients. Patients with subchondral insufficiency fracture characteristically have unremarkable plain radiographs, while MRI examination may reveal extensive bone marrow oedema and subchondral bone collapse. This article presents a 51-year-old postmenopausal woman, a physician, who had subchondral insufficiency fractures of the knee associated with prolonged standing during clinical work. She was treated with partial weight bearing on crutches until 14 months after the injury, viscosupplementation at 4 months to treat osteoarthritis and teriparatide treatment to improve bone healing at 7 months. By 26 months after the injury, she tolerated independent walking with a fabric knee support but still experienced mild posterolateral knee pain and numbness on prolonged standing. 2015 BMJ Publishing Group Ltd.

Robust inference from multiple test statistics via permutations: a better alternative to the single test statistic approach for randomized trials.

Science.gov (United States)

Ganju, Jitendra; Yu, Xinxin; Ma, Guoguang Julie

2013-01-01

Formal inference in randomized clinical trials is based on controlling the type I error rate associated with a single pre-specified statistic. The deficiency of using just one method of analysis is that it depends on assumptions that may not be met. For robust inference, we propose pre-specifying multiple test statistics and relying on the minimum p-value for testing the null hypothesis of no treatment effect. The null hypothesis associated with the various test statistics is that the treatment groups are indistinguishable. The critical value for hypothesis testing comes from permutation distributions. Rejection of the null hypothesis when the smallest p-value is less than the critical value controls the type I error rate at its designated value. Even if one of the candidate test statistics has low power, the adverse effect on the power of the minimum p-value statistic is not much. Its use is illustrated with examples. We conclude that it is better to rely on the minimum p-value rather than a single statistic particularly when that single statistic is the logrank test, because of the cost and complexity of many survival trials. Copyright © 2013 John Wiley & Sons, Ltd.

Predictive factors of adrenal insufficiency in patients admitted to acute medical wards: a case control study

Directory of Open Access Journals (Sweden)

Oboni Jean-Baptiste

2013-01-01

Full Text Available Abstract Background Adrenal insufficiency is a rare and potentially lethal disease if untreated. Several clinical signs and biological markers are associated with glucocorticoid failure but the importance of these factors for diagnosing adrenal insufficiency is not known. In this study, we aimed to assess the prevalence of and the factors associated with adrenal insufficiency among patients admitted to an acute internal medicine ward. Methods Retrospective, case-control study including all patients with high-dose (250 μg ACTH-stimulation tests for suspected adrenal insufficiency performed between 2008 and 2010 in an acute internal medicine ward (n = 281. Cortisol values Results 32 patients (11.4% presented adrenal insufficiency; the others served as controls. Among all clinical and biological parameters studied, history of glucocorticoid withdrawal was the only independent factor significantly associated with patients with adrenal insufficiency (Odds Ratio: 6.71, 95% CI: 3.08 –14.62. Using a logistic regression, a model with four significant and independent variable was obtained, regrouping history of glucocorticoid withdrawal (OR 7.38, 95% CI [3.18 ; 17.11], p-value p-value 0.044, eosinophilia (OR 17.6, 95% CI [1.02; 302.3], p-value 0.048 and hyperkalemia (OR 2.41, 95% CI [0.87; 6.69], p-value 0.092. The AROC (95% CI was 0.75 (0.70; 0.80 for this model, with 6.3 (0.8 – 20.8 for sensitivity and 99.2 (97.1 – 99.9 for specificity. Conclusions 11.4% of patients with suspected adrenal insufficient admitted to acute medical ward actually do present with adrenal insufficiency, defined by an abnormal response to high-dose (250 μg ACTH-stimulation test. A history of glucocorticoid withdrawal was the strongest factor predicting the potential adrenal failure. The combination of a history of glucocorticoid withdrawal, nausea, eosinophilia and hyperkaliemia might be of interest to suspect adrenal insufficiency.

A goodness of fit statistic for the geometric distribution

NARCIS (Netherlands)

J.A. Ferreira

2003-01-01

textabstractWe propose a goodness of fit statistic for the geometric distribution and compare it in terms of power, via simulation, with the chi-square statistic. The statistic is based on the Lau-Rao theorem and can be seen as a discrete analogue of the total time on test statistic. The results

Primordial statistical anisotropy generated at the end of inflation

International Nuclear Information System (INIS)

Yokoyama, Shuichiro; Soda, Jiro

2008-01-01

We present a new mechanism for generating primordial statistical anisotropy of curvature perturbations. We introduce a vector field which has a non-minimal kinetic term and couples with a waterfall field in a hybrid inflation model. In such a system, the vector field gives fluctuations of the end of inflation and hence induces a subcomponent of curvature perturbations. Since the vector has a preferred direction, the statistical anisotropy could appear in the fluctuations. We present the explicit formula for the statistical anisotropy in the primordial power spectrum and the bispectrum of curvature perturbations. Interestingly, there is the possibility that the statistical anisotropy does not appear in the power spectrum but does appear in the bispectrum. We also find that the statistical anisotropy provides the shape dependence to the bispectrum

Primordial statistical anisotropy generated at the end of inflation

Energy Technology Data Exchange (ETDEWEB)

Yokoyama, Shuichiro [Department of Physics and Astrophysics, Nagoya University, Aichi 464-8602 (Japan); Soda, Jiro, E-mail: shu@a.phys.nagoya-u.ac.jp, E-mail: jiro@tap.scphys.kyoto-u.ac.jp [Department of Physics, Kyoto University, Kyoto 606-8501 (Japan)

2008-08-15

We present a new mechanism for generating primordial statistical anisotropy of curvature perturbations. We introduce a vector field which has a non-minimal kinetic term and couples with a waterfall field in a hybrid inflation model. In such a system, the vector field gives fluctuations of the end of inflation and hence induces a subcomponent of curvature perturbations. Since the vector has a preferred direction, the statistical anisotropy could appear in the fluctuations. We present the explicit formula for the statistical anisotropy in the primordial power spectrum and the bispectrum of curvature perturbations. Interestingly, there is the possibility that the statistical anisotropy does not appear in the power spectrum but does appear in the bispectrum. We also find that the statistical anisotropy provides the shape dependence to the bispectrum.

Maximizing Statistical Power When Verifying Probabilistic Forecasts of Hydrometeorological Events

Science.gov (United States)

DeChant, C. M.; Moradkhani, H.

2014-12-01

Hydrometeorological events (i.e. floods, droughts, precipitation) are increasingly being forecasted probabilistically, owing to the uncertainties in the underlying causes of the phenomenon. In these forecasts, the probability of the event, over some lead time, is estimated based on some model simulations or predictive indicators. By issuing probabilistic forecasts, agencies may communicate the uncertainty in the event occurring. Assuming that the assigned probability of the event is correct, which is referred to as a reliable forecast, the end user may perform some risk management based on the potential damages resulting from the event. Alternatively, an unreliable forecast may give false impressions of the actual risk, leading to improper decision making when protecting resources from extreme events. Due to this requisite for reliable forecasts to perform effective risk management, this study takes a renewed look at reliability assessment in event forecasts. Illustrative experiments will be presented, showing deficiencies in the commonly available approaches (Brier Score, Reliability Diagram). Overall, it is shown that the conventional reliability assessment techniques do not maximize the ability to distinguish between a reliable and unreliable forecast. In this regard, a theoretical formulation of the probabilistic event forecast verification framework will be presented. From this analysis, hypothesis testing with the Poisson-Binomial distribution is the most exact model available for the verification framework, and therefore maximizes one's ability to distinguish between a reliable and unreliable forecast. Application of this verification system was also examined within a real forecasting case study, highlighting the additional statistical power provided with the use of the Poisson-Binomial distribution.

Should we Investigate Gastroenterology Patients for Pancreatic Exocrine Insufficiency? A Dual Centre UK Study.

Science.gov (United States)

Campbell, Jennifer A; Sanders, David S; Francis, Katherine A; Kurien, Matthew; Lee, Sai; Taha, Hatim; Ramadas, Arvind; Joy, Diamond; Hopper, Andrew D

2016-09-01

Pancreatic exocrine insufficiency may be under recognised in gastroenterological practice. We aimed to identify the prevalence of pancreatic insufficiency in secondary care gastroenterology clinics and determine if co-morbidity or presenting symptoms could predict diagnosis. A secondary aim was to assess response to treatment. A dual centre retrospective analysis was conducted in secondary care gastroenterology clinics. Patients tested for pancreatic exocrine insufficiency with faecal elastase-1 (FEL-1) between 2009 and 2013 were identified in two centres. Demographics, indication and co-morbidities were recorded in addition to dose and response to pancreatic enzyme replacement therapy. Binary logistic regression was used to assess if symptoms or co-morbidities could predict pancreatic insufficiency. 1821 patients were tested, 13.1% had low FEL-1 (<200µg/g). This prevalence was sub-analysed with 5.4% having FEL-1 100-200µg/g (mild insufficiency) and 7.6% having faecal elastase readings <100µg/g. Low FEL-1 was most significantly associated with weight loss or steatorrhoea. Co-morbidity analysis showed that low levels were significantly associated with excess alcohol intake, diabetes mellitus or human immunodeficiency virus; 80.0% treated with enzyme supplements reported symptomatic benefit with no difference in response between high and low dose supplementation (p=0.761). Targeting the use of FEL-1 in individuals with specific symptoms and associated conditions can lead to improved recognition of pancreatic exocrine insufficiency in a significant proportion of secondary care patients. Intervening with lifestyle advice such as smoking cessation and minimising alcohol intake could improve outcomes. In addition, up to 80% of patients with low faecal elastase respond to supplementation.

R for statistics

CERN Document Server

Cornillon, Pierre-Andre; Husson, Francois; Jegou, Nicolas; Josse, Julie; Kloareg, Maela; Matzner-Lober, Eric; Rouviere, Laurent

2012-01-01

An Overview of RMain ConceptsInstalling RWork SessionHelpR ObjectsFunctionsPackagesExercisesPreparing DataReading Data from FileExporting ResultsManipulating VariablesManipulating IndividualsConcatenating Data TablesCross-TabulationExercisesR GraphicsConventional Graphical FunctionsGraphical Functions with latticeExercisesMaking Programs with RControl FlowsPredefined FunctionsCreating a FunctionExercisesStatistical MethodsIntroduction to the Statistical MethodsA Quick Start with RInstalling ROpening and Closing RThe Command PromptAttribution, Objects, and FunctionSelectionOther Rcmdr PackageImporting (or Inputting) DataGraphsStatistical AnalysisHypothesis TestConfidence Intervals for a MeanChi-Square Test of IndependenceComparison of Two MeansTesting Conformity of a ProportionComparing Several ProportionsThe Power of a TestRegressionSimple Linear RegressionMultiple Linear RegressionPartial Least Squares (PLS) RegressionAnalysis of Variance and CovarianceOne-Way Analysis of VarianceMulti-Way Analysis of Varian...

Wind power prediction models

Science.gov (United States)

Levy, R.; Mcginness, H.

1976-01-01

Investigations were performed to predict the power available from the wind at the Goldstone, California, antenna site complex. The background for power prediction was derived from a statistical evaluation of available wind speed data records at this location and at nearby locations similarly situated within the Mojave desert. In addition to a model for power prediction over relatively long periods of time, an interim simulation model that produces sample wind speeds is described. The interim model furnishes uncorrelated sample speeds at hourly intervals that reproduce the statistical wind distribution at Goldstone. A stochastic simulation model to provide speed samples representative of both the statistical speed distributions and correlations is also discussed.

Preliminary results after upper cervical chiropractic care in patients with chronic cerebro-spinal venous insufficiency and multiple sclerosis.

Science.gov (United States)

Mandolesi, Sandro; Marceca, Giuseppe; Moser, Jon; Niglio, Tarcisio; d'Alessandro, Aldo; Ciccone, Matteo Marco; Zito, Annapaola; Mandolesi, Dimitri; d'Alessandro, Alessandro; Fedele, Francesco

2015-01-01

The aim of the study is to evaluate the clinical and X-ray results of the Upper Cervical Chiropractic care through the specific adjustments (corrections) of C1-C2 on patients with chronic venous cerebral-spinal insufficiency (CCSVI) and multiple sclerosis (MS). We studied a sample of 77 patients before and after the Upper Cervical Chiropractic care, and we analyzed: A) The change of the X-ray parameters; B) The clinical results using a new set of questions. The protocol of the C1- C2 upper Cervical Chiropractic treatment, specific for these patients, lasts four months. From a haemodynamic point of view we divided the patients in 3 types: Type 1 - purely vascular with intravenous alterations; Type 2 - "mechanical" with of external venous compressions; Type 3 - mixed. We found an improvement in all kinds of subluxations after the treatment with respect to the pre-treatment X-ray evaluation, with a significant statistical difference. The differences between the clinical symptoms before and after the specific treatment of C1-C2 are statistically significant with pcerebro-spinal fluid.

A NANOS3 mutation linked to protein degradation causes premature ovarian insufficiency

OpenAIRE

Wu, X; Wang, B; Dong, Z; Zhou, S; Liu, Z; Shi, G; Cao, Y; Xu, Y

2013-01-01

Primary ovarian insufficiency (POI), or premature ovarian failure, is defined as the cessation of ovarian function before the age of 40. An insufficient ovarian follicle pool derived from primordial germ cells (PGCs) is an important cause of POI. Although the Nanos gene family is known to be required for PGC development and maintenance in diverse model organisms, the relevance of this information to human biology is not yet clear. In this study, we screened the coding regions of the NANOS1, N...

Insufficient evidence to assess the effectiveness of antibiotics for irreversible pulpitis.

Science.gov (United States)

George, Roy

2014-03-01

The Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Embase and the US National Institutes of Health Trials Register. Randomised controlled trials (RCTs) which compared pain relief with systemic antibiotics and analgesics, against placebo and analgesics in the acute preoperative phase of irreversible pulpitis. Study selection, risk of bias assessment and data extraction were carried out independently by two reviewers. Pooling of data was not possible and a descriptive summary is presented. One trial assessed at low risk of bias, involving 40 participants, was included in this update of the review. The quality of the body of evidence was rated low for the different outcomes. There was a close parallel distribution of the pain ratings in both the intervention and placebo groups over the seven-day study period.There was insufficient evidence to claim or refute a benefit for penicillin for pain intensity. There was no significant difference in the mean total number of ibuprofen tablets taken over the study period: 9.2 (standard deviation (SD) 6.02) in the penicillin group versus 9.6 (SD 6.34) in the placebo group; mean difference -0.40 (95% confidence interval (CI) -4.23 to 3.43; P value = 0.84). This applied equally for the mean total number of Tylenol tablets: 6.9 (SD 6.87) used in the penicillin group versus 4.45 (SD 4.82) in the placebo group; mean difference 2.45 (95% CI -1.23 to 6.13; P value = 0.19). Our secondary outcome on reporting of adverse events was not addressed in this study. This systematic, review which was based on one low-powered small sample trial assessed as a low risk of bias, illustrates that there is insufficient evidence to determine whether antibiotics reduce pain or not compared to not having antibiotics. The results of this review confirm the necessity for further larger sample and methodologically sound trials that can provide additional evidence as to whether antibiotics

THE MODERN APPROACH OF CHILDREN’S TREATMENT WITH VELOPHARYNGEAL INSUFFICIENCY IN THE POSTOPERATIVE PERIOD

Directory of Open Access Journals (Sweden)

O. V. Nelyubina

2014-01-01

Full Text Available Velopharyngeal insufficiency is one of the main causes of speech disorders in children with congenital cleft palate, leading to social exclusion and disability of patients. This article describes an integrated approach to the treatment of velopharyngeal insufficiency, aimed in improving the anatomical and physiological function of velopharyngeal ring. Velopharyngeal ring is considered as the nervemuscle complex in the treatment of patients with this pathology. It is shown that a one-time complex treatment of velopharyngeal insufficiency, estimated with the program «Compare» in the below-described clinical example, increased velopharyngeal closure ring by 25%, thus eliminating nasality and significantly improve the quality of speech.

Fundamentals of modern statistical methods substantially improving power and accuracy

CERN Document Server

Wilcox, Rand R

2001-01-01

Conventional statistical methods have a very serious flaw They routinely miss differences among groups or associations among variables that are detected by more modern techniques - even under very small departures from normality Hundreds of journal articles have described the reasons standard techniques can be unsatisfactory, but simple, intuitive explanations are generally unavailable Improved methods have been derived, but they are far from obvious or intuitive based on the training most researchers receive Situations arise where even highly nonsignificant results become significant when analyzed with more modern methods Without assuming any prior training in statistics, Part I of this book describes basic statistical principles from a point of view that makes their shortcomings intuitive and easy to understand The emphasis is on verbal and graphical descriptions of concepts Part II describes modern methods that address the problems covered in Part I Using data from actual studies, many examples are include...

Long-term results of external valvuloplasty in adult patients with isolated great saphenous vein insufficiency

Directory of Open Access Journals (Sweden)

Sarac A

2014-04-01

Full Text Available Atilla Sarac,1 Artan Jahollari,1 Sureyya Talay,1 Sevket Ozkaya,2 Ertugrul Ozal1 1Department of Cardiovascular Medicine, Samsun Medical Park Hospital, Samsun, Turkey; 2Department of Pulmonary Medicine, Faculty of Medicine, Bahcesehir University, Istanbul, Turkey Objective: The aim of this study is to present our 7-year results of external valvuloplasty for isolated great saphenous vein (GSV insufficiency. Methods: External valvuloplasty was applied in 83 patients with isolated GSV insufficiency. Follow-up consisted of venous color duplex scanning performed on the first postoperative day, the first postoperative month, and then annually. Valvular insufficiency, venous reflux, and venous thrombosis formation in the saphenofemoral junction were the main outcomes. Results: A complete clinical and radiological healing was observed in 50 patients (60%. In 13 cases (15.6%, a secondary surgical treatment was performed consisting of vena saphena magna high ligation/stripping and varicose vein excisions, mainly due to severe and progressive vena saphena magna valvular insufficiency and clinical persistence of symptoms. Eight patients (9.6% developed superficial vein thrombosis, and only one patient (1.2% developed deep vein thrombosis. Contact was lost from 32 patients (38.5% for different reasons. Conclusion: External valvuloplasty is an effective surgical technique for selected cases of isolated GSV insufficiency without extensive varicose dilatations. This alternative method can be safely administered as an alternative to high ligation and conventional GSV stripping. Keyword: vein, saphenous, insufficiency, external valv, valvuloplasty, varicosis

Fatigue and insufficiency fractures

International Nuclear Information System (INIS)

Lodwick, G.S.; Rosenthal, D.I.; Kattapuram, S.V.; Hudson, T.M.

1987-01-01

The incidence of stress fracture is increasing. In our younger society this is due largely to a preocupation with physical conditioning, but in our elderly population it is due to improved recognition and better methods of detection and diagnosis. Stress fracture of the elderly is an insufficiency fracture which occurs in the spine, the pelvis, the sacrum and other bones afflicted with disorders which cause osteopenia. Stress fracture is frequently misdiagnosed as a malignant lesion of bone resulting in biopsy. Scintiscanning provides the greatest frequency of detection, while computed tomography often provides the definitive diagnosis. With increased interest and experience a better insight into the disease has been achieved, and what was once thought of as a simple manifestation of mechanical stress is now known to be an orderly, complex pattern of physiological changes in bone which conform to a model by Frost. The diffuse nature of these changes can be recognized by scintigraphy, radiography and magnetic resonance imaging. 27 refs.; 8 figs

Statistical analysis of nuclear power plant pump failure rate variability: some preliminary results

International Nuclear Information System (INIS)

Martz, H.F.; Whiteman, D.E.

1984-02-01

In-Plant Reliability Data System (IPRDS) pump failure data on over 60 selected pumps in four nuclear power plants are statistically analyzed using the Failure Rate Analysis Code (FRAC). A major purpose of the analysis is to determine which environmental, system, and operating factors adequately explain the variability in the failure data. Catastrophic, degraded, and incipient failure severity categories are considered for both demand-related and time-dependent failures. For catastrophic demand-related pump failures, the variability is explained by the following factors listed in their order of importance: system application, pump driver, operating mode, reactor type, pump type, and unidentified plant-specific influences. Quantitative failure rate adjustments are provided for the effects of these factors. In the case of catastrophic time-dependent pump failures, the failure rate variability is explained by three factors: reactor type, pump driver, and unidentified plant-specific influences. Finally, point and confidence interval failure rate estimates are provided for each selected pump by considering the influential factors. Both types of estimates represent an improvement over the estimates computed exclusively from the data on each pump

Electric loading of power transmission lines - statistical methodology and real time management; Carregamento eletrico de linhas de transmissao - metodologia estatistica e gerenciamento em tempo real

Energy Technology Data Exchange (ETDEWEB)

Diniz, Jose H.; Leao, Sergio L.C.; Paim, Oswaldo; Martins, Jose A.; Costa, Jonas A. da [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil)

1991-12-31

This paper shows a computerized system, that adopt a statistical methodology and simultaneous measurements of wind velocity and environment temperature, as an experiences at the power transmission lines with environmental monitoring systems. 9 figs., 16 refs.

Assessment of environmental impacts of nuclear power plants

International Nuclear Information System (INIS)

Horacek, P.

1990-01-01

The effects of normal operation and of accidents are analyzed. It is pointed out that the public is insufficiently informed, which bears anxiety and prejudice. The effective dose equivalents for the population and for the individual, measured during operation of the Bohunice nuclear power plants are listed and compared with those from natural background and from medical applications. The possible radioactive contamination of a large area of agricultural soil is the highest specific risk of nuclear power plant operation. Problems are growing related to spent fuel disposal and eventually to the decommissioning of the power plant itself. (M.D.). 1 tab., 8 refs

Clinicoroentgenological diagnosis of chronic venous ovarian insufficiency

International Nuclear Information System (INIS)

Grakova, L.S.; Galkin, E.V.; Naumova, E.B.

1989-01-01

The paper is devoted to clinicoroentgenological correlations of venous renogonadal hemodynamics in 168 women of reproductive age (151 women with infertility, habitual abortion, disordered menstrual function and 17 patients without disorders of the reproductive tract). Clinicolaboratory investigation was followed by visceral and parietal flebography for the detection of a pathological venous reflux into the ovarian pampiniform plexus. Clinicoroentgenological semiotics of chronic venous ovarian insufficiency was analyzed. Infertility was shown to be the main clinical manifestation of ovarian varicocele

Respiratory insufficiency with preserved diaphragmatic function in amyotrophic lateral sclerosis.

Science.gov (United States)

Yamauchi, Rika; Imai, Tomihiro; Tsuda, Emiko; Hozuki, Takayoshi; Yamamoto, Daisuke; Shimohama, Shun

2014-01-01

We performed a longitudinal study to elucidate the correlation between respiratory insufficiency and respiratory biomarkers, including diaphragmatic compound muscle action potential (DCMAP), at the initiation of noninvasive ventilation (NIV) in patients with amyotrophic lateral sclerosis (ALS). The patients were assessed at least every six months. Additional assessments were performed at the start of respiratory therapy when the patients met the criteria for the initiation of NIV. Each assessment consisted of a full neurological examination, a phrenic nerve conduction study, respiratory function tests, and nocturnal pulsed oximetry. We enrolled 43 patients with either definite or probable ALS as defined by the revised El Escorial criteria. The patients were divided into two groups according to the timing of the initiation of respiratory therapy. Seventeen patients (group A) met the criteria for NIV initiation when their DCMAP remained normal. Twenty-six patients (group B) met the criteria when their DCMAP decreased below normal limits. Although respiratory function parameters were significantly worse in group B compared with group A at NIV initiation, more than 80% of the patients in both groups developed nocturnal desaturation during sleep. DCMAP is not always a reliable indicator for determining the optimal timing for NIV initiation during the progression of respiratory insufficiency in ALS. Physicians should be aware of the risk of respiratory insufficiency during sleep in patients with ALS.

Statistical inference for financial engineering

CERN Document Server

Taniguchi, Masanobu; Ogata, Hiroaki; Taniai, Hiroyuki

2014-01-01

This monograph provides the fundamentals of statistical inference for financial engineering and covers some selected methods suitable for analyzing financial time series data. In order to describe the actual financial data, various stochastic processes, e.g. non-Gaussian linear processes, non-linear processes, long-memory processes, locally stationary processes etc. are introduced and their optimal estimation is considered as well. This book also includes several statistical approaches, e.g., discriminant analysis, the empirical likelihood method, control variate method, quantile regression, realized volatility etc., which have been recently developed and are considered to be powerful tools for analyzing the financial data, establishing a new bridge between time series and financial engineering. This book is well suited as a professional reference book on finance, statistics and statistical financial engineering. Readers are expected to have an undergraduate-level knowledge of statistics.

Evaluation of clustering statistics with N-body simulations

International Nuclear Information System (INIS)

Quinn, T.R.

1986-01-01

Two series of N-body simulations are used to determine the effectiveness of various clustering statistics in revealing initial conditions from evolved models. All the simulations contained 16384 particles and were integrated with the PPPM code. One series is a family of models with power at only one wavelength. The family contains five models with the wavelength of the power separated by factors of √2. The second series is a family of all equal power combinations of two wavelengths taken from the first series. The clustering statistics examined are the two point correlation function, the multiplicity function, the nearest neighbor distribution, the void probability distribution, the distribution of counts in cells, and the peculiar velocity distribution. It is found that the covariance function, the nearest neighbor distribution, and the void probability distribution are relatively insensitive to the initial conditions. The distribution of counts in cells show a little more sensitivity, but the multiplicity function is the best of the statistics considered for revealing the initial conditions

Statistical inference based on divergence measures

CERN Document Server

Pardo, Leandro

2005-01-01

The idea of using functionals of Information Theory, such as entropies or divergences, in statistical inference is not new. However, in spite of the fact that divergence statistics have become a very good alternative to the classical likelihood ratio test and the Pearson-type statistic in discrete models, many statisticians remain unaware of this powerful approach.Statistical Inference Based on Divergence Measures explores classical problems of statistical inference, such as estimation and hypothesis testing, on the basis of measures of entropy and divergence. The first two chapters form an overview, from a statistical perspective, of the most important measures of entropy and divergence and study their properties. The author then examines the statistical analysis of discrete multivariate data with emphasis is on problems in contingency tables and loglinear models using phi-divergence test statistics as well as minimum phi-divergence estimators. The final chapter looks at testing in general populations, prese...

Assessing adrenal insufficiency of corticosteroid secretion using free versus total cortisol levels in critical illness

NARCIS (Netherlands)

Molenaar, N.; Groeneveld, A.B.J.; Dijstelbloem, H.M.; de Jong, M.F.C.; Girbes, A.R.J.; Heijboer, A.C.; Beishuizen, A.

2011-01-01

Purpose: To study the value of free versus total cortisol levels in assessing relative adrenal insufficiency during critical illness-related corticosteroid insufficiency. Methods: A prospective study in a mixed intensive care unit from 2004 to 2007. We consecutively included 49 septic and 63

Electric power annual 1997. Volume 2

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-10-01

The Electric Power Annual 1997, Volume 2 contains annual summary statistics at national, regional, and state levels for the electric power industry, including information on both electric utilities and nonutility power producers. Included are data for electric utility retail sales of electricity, associated revenue, and average revenue per kilowatthour of electricity sold; financial statistics; environmental statistics; power transactions; and demand-side management. Also included are data for US nonutility power producers on installed capacity; gross generation; emissions; and supply and disposition of energy. The objective of the publication is to provide industry decisionmakers, government policymakers, analysts, and the general public with historical data that may be used in understanding US electricity markets. 15 figs., 62 tabs.

A goodness of fit statistic for the geometric distribution

OpenAIRE

Ferreira, J.A.

2003-01-01

textabstractWe propose a goodness of fit statistic for the geometric distribution and compare it in terms of power, via simulation, with the chi-square statistic. The statistic is based on the Lau-Rao theorem and can be seen as a discrete analogue of the total time on test statistic. The results suggest that the test based on the new statistic is generally superior to the chi-square test.

Optimization of power rationing order based on fuzzy evaluation model

Science.gov (United States)

Zhang, Siyuan; Liu, Li; Xie, Peiyuan; Tang, Jihong; Wang, Canlin

2018-04-01

With the development of production and economic growth, China's electricity load has experienced a significant increase. Over the years, in order to alleviate the contradiction of power shortage, a series of policies and measures to speed up electric power construction have been made in china, which promotes the rapid development of the power industry and the power construction has made great achievements. For China, after large-scale power facilities, power grid long-term power shortage situation has been improved to some extent, but in a certain period of time, the power development still exists uneven development. On the whole, it is still in the state of insufficient power, and the situation of power restriction is still severe in some areas, so it is necessary to study on the power rationing.

[Experimental validation of the efficacy of laser-magnetic therapy for chronic placental insufficiency].

Science.gov (United States)

Ordzhonikidze, N V; Filimonov, V G; Klimenko, P A; Kondrikov, N I; Akin'shina, V S; Berlin, Iu V

1994-01-01

A new pathogenetically based non-medicamentous method for correction of uteroplacental bloodflow disturbances has been developed on the model of chronic placental insufficiency in rats. A single 5 min laser-magnetic exposure on day 21 of normal pregnancy resulted in a vasodilating effect with reduction of the peripheral resistance in the uterine horn vessels and with improvement of their blood supply. A new LAMA laser magneto-therapeutic device was employed. Daily 5 min sessions of laser magnetic therapy administered to rats with chronic placental insufficiency from pregnancy days 15-16 to 21 normalized uterine horn contractility and resulted in positive morphofunctional changes in the components of the uterine horns and placenta, being associated with a noticeable improvement of fetal functions. Hence, laser magnetic therapy may be regarded as an effective non-drug method for therapy of chronic placental insufficiency.

Reversible adrenal insufficiency and heterophile antibodies in a case of autoimmune polyendocrinopathy syndrome.

Science.gov (United States)

Kharb, Sandeep; Gundgurthi, Abhay; Dutta, Manoj K; Garg, M K

2013-12-01

A 27-year-old male was admitted with diabetic ketoacidosis and altered sensorium with slurring of speech and ataxia. He was managed with intravenous insulin and fluids and later shifted to basal bolus insulin regimen and during further evaluation was diagnosed to be suffering from primary hypothyroidism and adrenal insufficiency. He was started on thyroxin replacement and steroids only during stress. After three months of follow up he was clinically euthyroid. His glycemic control was adequate on oral anti-hyperglycemic drugs and adrenal insufficiency recovered. However, his thyrotropin levels were persistently elevated on adequate replacement doses of thyroxin. His repeat TSH was estimated after precipitating serum with polyethylene glycol which revealed normal TSH. Here we report reversible adrenal insufficiency with hypothyroidism with falsely raised TSH because of presence of heterophile antibodies in a case of poly glandular endocrinopathy syndrome.

Power-Efficient Beacon Recognition Method Based on Periodic Wake-Up for Industrial Wireless Devices.

Science.gov (United States)

Song, Soonyong; Lee, Donghun; Jang, Ingook; Choi, Jinchul; Son, Youngsung

2018-04-17

Energy harvester-integrated wireless devices are attractive for generating semi-permanent power from wasted energy in industrial environments. The energy-harvesting wireless devices may have difficulty in their communication with access points due to insufficient power supply for beacon recognition during network initialization. In this manuscript, we propose a novel method of beacon recognition based on wake-up control to reduce instantaneous power consumption in the initialization procedure. The proposed method applies a moving window for the periodic wake-up of the wireless devices. For unsynchronized wireless devices, beacons are always located in the same positions within each beacon interval even though the starting offsets are unknown. Using these characteristics, the moving window checks the existence of the beacon associated withspecified resources in a beacon interval, checks again for neighboring resources at the next beacon interval, and so on. This method can reduce instantaneous power and generates a surplus of charging time. Thus, the proposed method alleviates the problems of power insufficiency in the network initialization. The feasibility of the proposed method is evaluated using computer simulations of power shortage in various energy-harvesting conditions.

Photosensitivity and Acute Liver Insufficiency in Late-Onset Erythropoietic Protoporphyria with a Chromosome 18q Abnormality

Directory of Open Access Journals (Sweden)

Yuka Oshikawa

2012-07-01

Full Text Available Late-onset erythropoietic protoporphyria (EPP is rare, and it is usually associated with an acquired somatic mutation of the ferrochelatase gene secondary to hematological malignancy such as myelodysplastic syndrome or myeloproliferative disorder. In 0.5–1% of patients with EPP, deposition of protoporphyrin in the liver leads to progressive liver insufficiency. Herein, we report the case of a 67-year-old female who developed EPP with typical photosensitivity and hemolytic anemia. Six months later, she was admitted with acute liver damage with a rapidly progressing course, and developed liver insufficiency. She recovered from the liver insufficiency after undergoing plasmapheresis and red blood cell exchange transfusion. A bone marrow examination revealed normal features; however, a cytogenetic analysis identified an abnormal clone of cells with a translocation between chromosomes 13q12 and 18q21.1. This is the first report of a patient who recovered from liver insufficiency. The results of this report suggest that plasmapheresis and red blood cell exchange transfusion are effective for treating liver insufficiency in patients with late-onset EPP.

BrightStat.com: free statistics online.

Science.gov (United States)

Stricker, Daniel

2008-10-01

Powerful software for statistical analysis is expensive. Here I present BrightStat, a statistical software running on the Internet which is free of charge. BrightStat's goals, its main capabilities and functionalities are outlined. Three different sample runs, a Friedman test, a chi-square test, and a step-wise multiple regression are presented. The results obtained by BrightStat are compared with results computed by SPSS, one of the global leader in providing statistical software, and VassarStats, a collection of scripts for data analysis running on the Internet. Elementary statistics is an inherent part of academic education and BrightStat is an alternative to commercial products.

Chronic Heroin Dependence Leading to Adrenal Insufficiency

Directory of Open Access Journals (Sweden)

Gautam Das

2014-01-01

Full Text Available Opioids have been the mainstay for pain relief and palliation over a long period of time. They are commonly abused by drug addicts and such dependence usually imparts severe physiologic effects on multiple organ systems. The negative impact of opioids on the endocrine system is poorly understood and often underestimated. We describe a patient who developed severe suppression of the hypothalamic-pituitary adrenal (HPA axis leading to secondary adrenal insufficiency due to long standing abuse of opioids.

Assessing adrenal insufficiency of corticosteroid secretion using free versus total cortisol levels in critical illness

NARCIS (Netherlands)

Molenaar, Nienke; Johan Groeneveld, A. B.; Dijstelbloem, Hilde M.; de Jong, Margriet F. C.; Girbes, Armand R. J.; Heijboer, Annemieke C.; Beishuizen, Albertus

2011-01-01

To study the value of free versus total cortisol levels in assessing relative adrenal insufficiency during critical illness-related corticosteroid insufficiency. A prospective study in a mixed intensive care unit from 2004 to 2007. We consecutively included 49 septic and 63 non-septic patients with

Why Sleep Matters-The Economic Costs of Insufficient Sleep: A Cross-Country Comparative Analysis.

Science.gov (United States)

Hafner, Marco; Stepanek, Martin; Taylor, Jirka; Troxel, Wendy M; van Stolk, Christian

2017-01-01

The Centers for Disease Control and Prevention (CDC) in the United States has declared insufficient sleep a "public health problem." Indeed, according to a recent CDC study, more than a third of American adults are not getting enough sleep on a regular basis. However, insufficient sleep is not exclusively a US problem, and equally concerns other industrialised countries such as the United Kingdom, Japan, Germany, or Canada. According to some evidence, the proportion of people sleeping less than the recommended hours of sleep is rising and associated with lifestyle factors related to a modern 24/7 society, such as psychosocial stress, alcohol consumption, smoking, lack of physical activity and excessive electronic media use, among others. This is alarming as insufficient sleep has been found to be associated with a range of negative health and social outcomes, including success at school and in the labour market. Over the last few decades, for example, there has been growing evidence suggesting a strong association between short sleep duration and elevated mortality risks. Given the potential adverse effects of insufficient sleep on health, well-being and productivity, the consequences of sleep-deprivation have far-reaching economic consequences. Hence, in order to raise awareness of the scale of insufficient sleep as a public-health issue, comparative quantitative figures need to be provided for policy- and decision-makers, as well as recommendations and potential solutions that can help tackling the problem.

Nocturnal foot blood flow in patients with arterial insufficiency

DEFF Research Database (Denmark)

Jelnes, Rolf; Tønnesen, K H

1984-01-01

Twenty-four hour continuous recording of xenon (133Xe) wash-out from the forefoot was performed on patients with normal circulations (n = 10) and on patients with different degrees of arterial insufficiency (n = 36). During day hours the calculated subcutaneous blood flow in the forefoot was on a...

Thresholds for statistical and clinical significance in systematic reviews with meta-analytic methods

DEFF Research Database (Denmark)

Jakobsen, Janus Christian; Wetterslev, Jorn; Winkel, Per

2014-01-01

BACKGROUND: Thresholds for statistical significance when assessing meta-analysis results are being insufficiently demonstrated by traditional 95% confidence intervals and P-values. Assessment of intervention effects in systematic reviews with meta-analysis deserves greater rigour. METHODS......: Methodologies for assessing statistical and clinical significance of intervention effects in systematic reviews were considered. Balancing simplicity and comprehensiveness, an operational procedure was developed, based mainly on The Cochrane Collaboration methodology and the Grading of Recommendations...... Assessment, Development, and Evaluation (GRADE) guidelines. RESULTS: We propose an eight-step procedure for better validation of meta-analytic results in systematic reviews (1) Obtain the 95% confidence intervals and the P-values from both fixed-effect and random-effects meta-analyses and report the most...

Developing a statistically powerful measure for quartet tree inference using phylogenetic identities and Markov invariants.

Science.gov (United States)

Sumner, Jeremy G; Taylor, Amelia; Holland, Barbara R; Jarvis, Peter D

2017-12-01

Recently there has been renewed interest in phylogenetic inference methods based on phylogenetic invariants, alongside the related Markov invariants. Broadly speaking, both these approaches give rise to polynomial functions of sequence site patterns that, in expectation value, either vanish for particular evolutionary trees (in the case of phylogenetic invariants) or have well understood transformation properties (in the case of Markov invariants). While both approaches have been valued for their intrinsic mathematical interest, it is not clear how they relate to each other, and to what extent they can be used as practical tools for inference of phylogenetic trees. In this paper, by focusing on the special case of binary sequence data and quartets of taxa, we are able to view these two different polynomial-based approaches within a common framework. To motivate the discussion, we present three desirable statistical properties that we argue any invariant-based phylogenetic method should satisfy: (1) sensible behaviour under reordering of input sequences; (2) stability as the taxa evolve independently according to a Markov process; and (3) explicit dependence on the assumption of a continuous-time process. Motivated by these statistical properties, we develop and explore several new phylogenetic inference methods. In particular, we develop a statistically bias-corrected version of the Markov invariants approach which satisfies all three properties. We also extend previous work by showing that the phylogenetic invariants can be implemented in such a way as to satisfy property (3). A simulation study shows that, in comparison to other methods, our new proposed approach based on bias-corrected Markov invariants is extremely powerful for phylogenetic inference. The binary case is of particular theoretical interest as-in this case only-the Markov invariants can be expressed as linear combinations of the phylogenetic invariants. A wider implication of this is that, for

[An investigation of the statistical power of the effect size in randomized controlled trials for the treatment of patients with type 2 diabetes mellitus using Chinese medicine].

Science.gov (United States)

Ma, Li-Xin; Liu, Jian-Ping

2012-01-01

To investigate whether the power of the effect size was based on adequate sample size in randomized controlled trials (RCTs) for the treatment of patients with type 2 diabetes mellitus (T2DM) using Chinese medicine. China Knowledge Resource Integrated Database (CNKI), VIP Database for Chinese Technical Periodicals (VIP), Chinese Biomedical Database (CBM), and Wangfang Data were systematically recruited using terms like "Xiaoke" or diabetes, Chinese herbal medicine, patent medicine, traditional Chinese medicine, randomized, controlled, blinded, and placebo-controlled. Limitation was set on the intervention course > or = 3 months in order to identify the information of outcome assessement and the sample size. Data collection forms were made according to the checking lists found in the CONSORT statement. Independent double data extractions were performed on all included trials. The statistical power of the effects size for each RCT study was assessed using sample size calculation equations. (1) A total of 207 RCTs were included, including 111 superiority trials and 96 non-inferiority trials. (2) Among the 111 superiority trials, fasting plasma glucose (FPG) and glycosylated hemoglobin HbA1c (HbA1c) outcome measure were reported in 9% and 12% of the RCTs respectively with the sample size > 150 in each trial. For the outcome of HbA1c, only 10% of the RCTs had more than 80% power. For FPG, 23% of the RCTs had more than 80% power. (3) In the 96 non-inferiority trials, the outcomes FPG and HbA1c were reported as 31% and 36% respectively. These RCTs had a samples size > 150. For HbA1c only 36% of the RCTs had more than 80% power. For FPG, only 27% of the studies had more than 80% power. The sample size for statistical analysis was distressingly low and most RCTs did not achieve 80% power. In order to obtain a sufficient statistic power, it is recommended that clinical trials should establish clear research objective and hypothesis first, and choose scientific and evidence

SIESE - trimestrial bulletin - Synthesis 1994. Electric power summary statistics for Brazil

International Nuclear Information System (INIS)

1994-01-01

The performance of the power system of all the Brazilian electrical utilities is presented. The data is given for each region in the country and includes, among other things, the electric power consumption and generation; the number of consumers and the electric power rates. 10 figs., 42 tabs

Combining Multiple Hypothesis Testing with Machine Learning Increases the Statistical Power of Genome-wide Association Studies

Science.gov (United States)

Mieth, Bettina; Kloft, Marius; Rodríguez, Juan Antonio; Sonnenburg, Sören; Vobruba, Robin; Morcillo-Suárez, Carlos; Farré, Xavier; Marigorta, Urko M.; Fehr, Ernst; Dickhaus, Thorsten; Blanchard, Gilles; Schunk, Daniel; Navarro, Arcadi; Müller, Klaus-Robert

2016-01-01

The standard approach to the analysis of genome-wide association studies (GWAS) is based on testing each position in the genome individually for statistical significance of its association with the phenotype under investigation. To improve the analysis of GWAS, we propose a combination of machine learning and statistical testing that takes correlation structures within the set of SNPs under investigation in a mathematically well-controlled manner into account. The novel two-step algorithm, COMBI, first trains a support vector machine to determine a subset of candidate SNPs and then performs hypothesis tests for these SNPs together with an adequate threshold correction. Applying COMBI to data from a WTCCC study (2007) and measuring performance as replication by independent GWAS published within the 2008–2015 period, we show that our method outperforms ordinary raw p-value thresholding as well as other state-of-the-art methods. COMBI presents higher power and precision than the examined alternatives while yielding fewer false (i.e. non-replicated) and more true (i.e. replicated) discoveries when its results are validated on later GWAS studies. More than 80% of the discoveries made by COMBI upon WTCCC data have been validated by independent studies. Implementations of the COMBI method are available as a part of the GWASpi toolbox 2.0. PMID:27892471

Permutation statistical methods an integrated approach

CERN Document Server

Berry, Kenneth J; Johnston, Janis E

2016-01-01

This research monograph provides a synthesis of a number of statistical tests and measures, which, at first consideration, appear disjoint and unrelated. Numerous comparisons of permutation and classical statistical methods are presented, and the two methods are compared via probability values and, where appropriate, measures of effect size. Permutation statistical methods, compared to classical statistical methods, do not rely on theoretical distributions, avoid the usual assumptions of normality and homogeneity of variance, and depend only on the data at hand. This text takes a unique approach to explaining statistics by integrating a large variety of statistical methods, and establishing the rigor of a topic that to many may seem to be a nascent field in statistics. This topic is new in that it took modern computing power to make permutation methods available to people working in the mainstream of research. This research monograph addresses a statistically-informed audience, and can also easily serve as a ...

Quantum fluctuation theorems and power measurements

International Nuclear Information System (INIS)

Prasanna Venkatesh, B; Watanabe, Gentaro; Talkner, Peter

2015-01-01

Work in the paradigm of the quantum fluctuation theorems of Crooks and Jarzynski is determined by projective measurements of energy at the beginning and end of the force protocol. In analogy to classical systems, we consider an alternative definition of work given by the integral of the supplied power determined by integrating up the results of repeated measurements of the instantaneous power during the force protocol. We observe that such a definition of work, in spite of taking account of the process dependence, has different possible values and statistics from the work determined by the conventional two energy measurement approach (TEMA). In the limit of many projective measurements of power, the system’s dynamics is frozen in the power measurement basis due to the quantum Zeno effect leading to statistics only trivially dependent on the force protocol. In general the Jarzynski relation is not satisfied except for the case when the instantaneous power operator commutes with the total Hamiltonian at all times. We also consider properties of the joint statistics of power-based definition of work and TEMA work in protocols where both values are determined. This allows us to quantify their correlations. Relaxing the projective measurement condition, weak continuous measurements of power are considered within the stochastic master equation formalism. Even in this scenario the power-based work statistics is in general not able to reproduce qualitative features of the TEMA work statistics. (paper)

Renal and suprarenal insufficiency secondary to familial Mediterranean fever associated with amyloidosis: a case report

Directory of Open Access Journals (Sweden)

Sari Nagehan

2011-08-01

Full Text Available Abstract Introduction Familial Mediterranean fever is an autosomal recessive disease that predominantly affects people of the Mediterranean coast. One of the most frequent complications of the disease is amyloidosis. This clinical entity is known as secondary (also called AA amyloidosis. Case presentation In this report, we describe the case of a 33-year-old Turkish man with familial Mediterranean fever and chronic renal insufficiency. He was admitted to our clinic with symptoms of suprarenal insufficiency. The patient died three months later as a result of cardiac arrest. Conclusion Our aim is to make a contribution to the literature by reporting a case of combined insufficiency due to the accumulation of renal and adrenal amyloid in a patient with familial Mediterranean fever, which has very rarely been described in the literature. We hope that adrenal insufficiency, which becomes fatal if not diagnosed and treated rapidly, will come to mind as easily as chronic renal failure in clinical practice.

Functional pancreatic insufficiency after surgical treatment in the light of the latest international recommendations

Directory of Open Access Journals (Sweden)

D. S. Bordin

2017-01-01

Full Text Available Exocrine  and  endocrine   insufficiencies  are  frequent complications of surgical treatment for pancreatic diseases. The presence  and  extent  of the insufficiency depend on the underlying  disorder, type of surgical procedure, extent of pancreatic resection, and anatomical reconstruction. Increased surgical  activity  determines  the  importance  of the  evidence-based guidelines  for management of patients  after  pancreatic  surgery. The article presents  an  overview of international Evidence-based Guidelines for the Management of Exocrine Pancreatic  Insufficiency after  Pancreatic  Surgery (2016 and United European Gastroenterology evidence-based guidelines  for the  diagnosis  and therapy of chronic pancreatitis (HaPanEU, 2017.

Retrospective study of effect of therapy on computer vision syndrome patients having convergence insufficiency

Directory of Open Access Journals (Sweden)

Nidhi Tiwari

2017-01-01

Full Text Available Aim: To study effect of therapy among computer users having convergence insufficiency. Materials and Methods: Hundred people between age group of 20-35 and who worked in IT companies were enrolled in the study. They were subjected to orthoptic evaluation to establish diagnosis of convergence insufficiency. They were then called for in-office therapy for 12 days daily. They underwent brock string exercises and at the end of therapy re-evaluation was done. Results: All the patients who underwent the therapy showed improvement in Near point of convergence at the end of therapy. They were also symptomatically better. Conclusions: Convergence insufficiency is a common occupation hazard among IT professionals. But it can be treated with appropriate therapy.

Statistics 101 for Radiologists.

Science.gov (United States)

Anvari, Arash; Halpern, Elkan F; Samir, Anthony E

2015-10-01

Diagnostic tests have wide clinical applications, including screening, diagnosis, measuring treatment effect, and determining prognosis. Interpreting diagnostic test results requires an understanding of key statistical concepts used to evaluate test efficacy. This review explains descriptive statistics and discusses probability, including mutually exclusive and independent events and conditional probability. In the inferential statistics section, a statistical perspective on study design is provided, together with an explanation of how to select appropriate statistical tests. Key concepts in recruiting study samples are discussed, including representativeness and random sampling. Variable types are defined, including predictor, outcome, and covariate variables, and the relationship of these variables to one another. In the hypothesis testing section, we explain how to determine if observed differences between groups are likely to be due to chance. We explain type I and II errors, statistical significance, and study power, followed by an explanation of effect sizes and how confidence intervals can be used to generalize observed effect sizes to the larger population. Statistical tests are explained in four categories: t tests and analysis of variance, proportion analysis tests, nonparametric tests, and regression techniques. We discuss sensitivity, specificity, accuracy, receiver operating characteristic analysis, and likelihood ratios. Measures of reliability and agreement, including κ statistics, intraclass correlation coefficients, and Bland-Altman graphs and analysis, are introduced. © RSNA, 2015.

Fire fighting precautions at Bohunice Atomic Power Plants

International Nuclear Information System (INIS)

Anon.

1984-01-01

Some shortcomings are discussed of the project design of fire protection at the V-1 and V-2 nuclear power plants. The basic shortcoming of the system is insufficient division of the units for fire protection. Fire fighting measures are described for cable areas, switch houses and outside transformers, primary and secondary circuits and auxiliary units. Measures are presented for increasing fire safety in Jaslovske Bohunice proceedi.ng from experience gained with a fire which had occurred at a nuclear power plant in Armenia. (E.S.)

Enrichment of statistical power for genome-wide association studies

Science.gov (United States)

The inheritance of most human diseases and agriculturally important traits is controlled by many genes with small effects. Identifying these genes, while simultaneously controlling false positives, is challenging. Among available statistical methods, the mixed linear model (MLM) has been the most fl...

Nasopharyngeal pushback in treatment of velopharyngeal insufficiency.

Science.gov (United States)

Smith, H W; Lee, K J

1976-02-01

We describe a new technique for extensive retropositioning of the soft palate for the treatment of velopharyngeal insufficiency. This technique is identified as a nasopharyngeal pushback, and has been used repeatedly in conjunction with both a Cronin nasal flap and a superiorly based pharyngeal flap when maximum retropositioning was needed. This procedure has been used for over ten years, each time obtaining an additional pushback distance equal to or greater than the distance achieved by freeling the soft palate from the posterior border of the hard palate.

[An update on the treatment of venous insufficiency in pregnancy].

Science.gov (United States)

Rodríguez-Nora, B; Álvarez-Silvares, E

Chronic venous insufficiency is a long-term pathological condition resulting from anatomical or functional alterations of the venous system. This leads to the appearance of symptoms and physical signs that affect a large part of the population and particularly pregnant women, due to the physiology of pregnancy. The few published studies on the use of pharmacological treatments of venous insufficiency in this group of the population, often makes the management of this condition difficult in routine clinical practice. A review is presented in this article, with all the latest updates in the treatment of this condition during pregnancy. There are numerous general, and some pharmacological, recommendations, that we can safely offer the pregnant patient. Copyright © 2017 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

Chemotherapy-Induced Regression of an Adrenocorticotropin-Secreting Pituitary Carcinoma Accompanied by Secondary Adrenal Insufficiency

Directory of Open Access Journals (Sweden)

Robert Frank Cornell

2013-01-01

Full Text Available Purpose. Adrenocorticotropin- (ACTH- secreting pituitary carcinomas are rare and require multimodality treatment. The aim of this study was to report the response to various therapies and discuss the potential development of secondary adrenal insufficiency with cytotoxic chemotherapy. Methods. This report describes a man with a large silent corticotroph adenoma progressing to endogenous hypercortisolism and metastatic ACTH-secreting pituitary carcinoma over a period of 14 years. Results. Seven years after initial presentation, progressive tumor enlargement associated with the development of hypercortisolism mandated multiple pituitary tumor debulking procedures and radiotherapy. Testing of the Ki-67 proliferation index was markedly high and he developed a hepatic metastasis. Combination therapy with cisplatin and etoposide resulted in a substantial reduction in tumor size, near-complete regression of his liver metastasis, and dramatic decrease in ACTH secretion. This unexpectedly resulted in symptomatic secondary adrenal insufficiency. Conclusions. This is the first reported case of secondary adrenal insufficiency after use of cytotoxic chemotherapy for metastatic ACTH-secreting pituitary carcinoma. High proliferative indices may be predictive of dramatic responses to chemotherapy. Given the potential for such responses, the development of secondary adrenal insufficiency may occur and patients should be monitored accordingly.

Introduction of a Successful Pregnancy in a Patient with Advanced Chronic Renal Insufficiency

Directory of Open Access Journals (Sweden)

H. Saghafi

2008-04-01

Full Text Available Background and ObjectiveIn the women with chronic renal insufficiency ovulation is suppressed therefore they rarely become pregnant. If pregnancy occurs, they might encounter many conflictions. It may lead to death (fetus or mother. The aim of this study was reporting a successful pregnancy in a patient with advanced chronic renal insufficiency.Case reportThe patient was a 32 years old woman with long period of infertility (8 years. The first main clinical symptom was abdominal pain especially in hypogastric area as well as hyperuremia, elevated levels of creatinine (2.9 mg/dl, mild proteinuria and hematuria. The urine specific gravity was 1010. Sonography data showed asymmetrical small kidneys. Other complaints were pruritus and flank pain during urination. The primary diagnosis was chronic renal failure due to probable chronic pyelonephritis. After an interval she returned with positive pregnancy test. She decided to continue the pregnancy in despite of obstetrician belief for aborting. During pregnancy, proteinuria reached to two plus, hemoglobin fell to 9.7, creatinine levels reached to 3.7 mg/dl and blood pressure was fluctuating between 110/80 and 130/85 mmHg. She admitted in the hospital in third trimester of pregnancy because of preterm labor. However the pain was suppressed after starting magnesium sulfate infusion. Keywords: Renal Insufficiency, Chronic Renal Insufficiency, Pregnancy

Risk assessment during operating self-propelled lifting jib cranes in conditions of insufficient information

Directory of Open Access Journals (Sweden)

Lagerev A.V.

2017-06-01

Full Text Available Presents the results of statistical analyses identified by the expert diagnostics of defects of the self-propelled lifting jib cranes, spent a normative term of exploitation. The greatest number of defects associated with the destruction and dete-rioration of structural elements, the occurrence of fatigue cracks and a violation of the conditions of operation of the equipment. The greatest number of defects occurs in the hydraulic system of cranes, the rope-block system, and rarely in steel structures. To conduct risk analysis of self-propelled jib cranes in case of insufficient information, proposed the method of expert estimations. It allows to assess the impact of potential defects on self-propelled jib cranes on the value of the economic damage of the crane and moving cargo and the value of the traumatic exposure on men. The proposed list of possible defects self-propelled lifting jib cranes and a checklist of questions about the degree of influence of these defects. Proposed calculated dependences to the approximate calculation of the magnitude of technical risk in the opera-tion of self-propelled jib cranes. The results of statistical analysis of expert estimations for each possible defect and per-formed their ranking in terms of impact on the magnitude of the economic damage of the crane and moving loads, the value of the traumatic exposure. Was calculated the value of technical risk for the surveyed taps.

Electric power annual 1989. [Contains glossary

Energy Technology Data Exchange (ETDEWEB)

1991-01-17

This publication presents a summary of electric utility statistics at the national, regional and state levels. The Industry At A Glance'' section presents a profile of the electric power industry ownership and performance; a review of key statistics for the year; and projections for various aspects of the electric power industry through 2010. Subsequent sections present data on generating capability, including proposed capability additions; net generation; fossil-fuel statistics; electricity sales, revenue and average revenue per kilowatthour sold; financial statistics; environmental statistics; and electric power transactions. In addition, the appendices provide supplemental data on major disturbances and unusual occurrences. Each section contains related text and tables and refers the reader to the appropriate publication that contains more detailed data on the subject matter. 24 figs., 57 tabs.

The Proteomic Analysis of Pancreatic Exocrine Insufficiency Protein Marker in Type 2 Diabetes Mellitus Patients

Science.gov (United States)

Srihardyastutie, Arie; Soeatmadji, DW; Fatchiyah; Aulanni'am

2018-01-01

Type 2 Diabetes Mellitus (T2D) is the vast majority case of diabetes. Patient with T2D is at higher risk for developing acute or chronic pancreatitis. Prolonged hyperglycemia results in damages to tissue, which also causes dysfunctions of some organ systems, including enzyme or hormone secretions. Commonly, dysfunction or insufficiency of pancreatic exocrine is evaluated by increasing activity of serum pancreatic enzyme, such as amylase and lipase. Although incidence of pancreatitis was found in Indonesian T2D, the pathogenic mechanism still unclear. The aim of this study was to characterize the marker protein that indicated the correlation of pancreatic exocrine insufficiency with progression of T2D. Proteomic analysis using LC-MS/MS was used in identification and characterization of protein marker which indicates insufficiency pancreatic exocrine. First step, protein profile was analyzed by SDS-PAGE methods using serum sample of T2D compared with normal or healthy control, as negative control, and pancreatitis patients, as positive control. Protein with 18 kDa was found as a candidate protein marker which indicated the pancreatic exocrine insufficiency in T2D. The further identification of that protein using LC-MS/MS showed 4 peptide fragments. In silico analysis of the peptide fragment indicated the correlation of pancreatic exocrine insufficiency with progression of T2D was METTL10 - methyltransferase like protein-10.

Energy statistics of pre-revolutionary Russia

Directory of Open Access Journals (Sweden)

N. S. Simonov

2017-01-01

Full Text Available The article is devoted to the problem of creation and development of the energy statistics of the Russian Empire of the initial stage of electrification and the formation of the energy economy, which is related to: 1 the economic upsurge of the 1890s; 2 the new economic recovery of 1907–1913 and 3 the militarization of industry in 1914–1916. The real technical and economic indicators and complex statistical data of the pre-revolutionary electric power industry were either hushed up or deliberately distorted during the Soviet era. Even in the encyclopaedic literature it was considered that pre-revolutionaryRussia“was on one of the last places in the world” for the production of electricity. The author analyzes statistical surveys (censuses of the manufacturing industry for 1900 and 1908 (the “varzar censuses”, which gave the first material on the state of its energy sector, namely: the composition, quantity and power of primary engines and electric motors. For the first time in historiography, the data of the “energy censuses” of the Ministry of Finance for 1905 and 1913 on the number and capacity of central public power stations and private power stations (block stations of industrial enterprises, organizations and institutions are cited. The data of the census were conducted with the participation of the apparatus of factory and factory inspections in 1906 and in1916 inall provinces of the Russian Empire, with the exception of six provinces of the frontline zone. A lot of work was done to record electricity production / consumption, which was conducted by the Russian electrotechnical community. According to incomplete data published in 1917 by the Secretariat of the Standing Committee of the VII All-Russia Electrotechnical Congress, from 1905 to 1913 (that is, for 8 years the total number of power stations in the Russian Empire increased by 1.7 times, and the amount of electricity produced by them Has grown in 3,8 times. The

Gibbs' theorem for open systems with incomplete statistics

International Nuclear Information System (INIS)

Bagci, G.B.

2009-01-01

Gibbs' theorem, which is originally intended for canonical ensembles with complete statistics has been generalized to open systems with incomplete statistics. As a result of this generalization, it is shown that the stationary equilibrium distribution of inverse power law form associated with the incomplete statistics has maximum entropy even for open systems with energy or matter influx. The renormalized entropy definition given in this paper can also serve as a measure of self-organization in open systems described by incomplete statistics.

Percutaneous treatment of thrombosed native arteriovenous dialysis fistula insufficiency: efficacy of mechanical thrombectomy with using the stone basket

International Nuclear Information System (INIS)

Kim, Young Hwan; Ko, Sung Min; Kim, Mi Jung; Kwon, Jung Hyeok; Sohn, Cheol Ho; Choi, Jin Soo; Park, Kyung Sik; Kim, Yong Joo

2006-01-01

We wanted to evaluate the procedural success after percutaneous treatment of thrombosed native arteriovenous dialysis fistula insufficiency and the efficacy of performing mechanical thrombectomy with using the stone basket. From March 2004 to June 2005, 36 thrombosed native hemodialysis access shunts in the upper limbs (brachiocephalic fistulas: 16 and radiocephalic fistulas: 20) were percutaneously treated in 30 patients. Declotting procedures were performed with using urokinase (100,00-200,000 unit) and manual catheter-directed thrombo-aspiration in all the patients. Angioplasty (6 mm in diameter and 4 cm in length) was performed at the identified area of the stenosis and /or with maceration of the thrombus. In 14 cases with massive thrombosis that was refractory to the above mentioned declotting procedures, mechanical thrombectomy with using a Wittich nitinol stone basket (Cook, Bloomington, IN) was performed. Data regarding the procedural success rate and the patency rate were analyzed by means of Fischer's exact test, and the Kaplan-Meier method with the Log-rank test was used for statistical inter-group comparisons between the brachiocephalic and radiocephalic fistulas. Successful declotting and restoration of thrill were achieved in 30 of 36 procedures (83%). Reestablishment of normal dialysis for at least one session was achieved in 29 of 36 procedures (81%). The procedural success rate for the brachiocephalic fistulas was 94% compared with 70% for the radiocephalic fistulas, but the difference was not statistically significant (ρ = 0.104). In the cases with performing mechanical thrombectomy and using the stone basket, procedural success was achieved in 93% (13/14). The expected patency rates at 3, 6 and 12 months were 78%, 61% and 51%, respectively. The patency rates after declotting procedures were not significantly different between the brachiocephalic and radiocephlaic fistulas (ρ = 0.871). Percutaneous treatment of thrombosed native arteriovenous

Percutaneous treatment of thrombosed native arteriovenous dialysis fistula insufficiency: efficacy of mechanical thrombectomy with using the stone basket

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Kim, Young Hwan; Ko, Sung Min; Kim, Mi Jung; Kwon, Jung Hyeok; Sohn, Cheol Ho; Choi, Jin Soo; Park, Kyung Sik [Dongsan Medical Center, Keimyung University College of Medicine, Daegu (Korea, Republic of); Kim, Yong Joo [Andong General Hospital, Andon (Korea, Republic of)

2006-06-15

We wanted to evaluate the procedural success after percutaneous treatment of thrombosed native arteriovenous dialysis fistula insufficiency and the efficacy of performing mechanical thrombectomy with using the stone basket. From March 2004 to June 2005, 36 thrombosed native hemodialysis access shunts in the upper limbs (brachiocephalic fistulas: 16 and radiocephalic fistulas: 20) were percutaneously treated in 30 patients. Declotting procedures were performed with using urokinase (100,00-200,000 unit) and manual catheter-directed thrombo-aspiration in all the patients. Angioplasty (6 mm in diameter and 4 cm in length) was performed at the identified area of the stenosis and /or with maceration of the thrombus. In 14 cases with massive thrombosis that was refractory to the above mentioned declotting procedures, mechanical thrombectomy with using a Wittich nitinol stone basket (Cook, Bloomington, IN) was performed. Data regarding the procedural success rate and the patency rate were analyzed by means of Fischer's exact test, and the Kaplan-Meier method with the Log-rank test was used for statistical inter-group comparisons between the brachiocephalic and radiocephalic fistulas. Successful declotting and restoration of thrill were achieved in 30 of 36 procedures (83%). Reestablishment of normal dialysis for at least one session was achieved in 29 of 36 procedures (81%). The procedural success rate for the brachiocephalic fistulas was 94% compared with 70% for the radiocephalic fistulas, but the difference was not statistically significant ({rho} = 0.104). In the cases with performing mechanical thrombectomy and using the stone basket, procedural success was achieved in 93% (13/14). The expected patency rates at 3, 6 and 12 months were 78%, 61% and 51%, respectively. The patency rates after declotting procedures were not significantly different between the brachiocephalic and radiocephlaic fistulas ({rho} = 0.871). Percutaneous treatment of thrombosed native

A Fractional Lower Order Statistics-Based MIMO Detection Method in Impulse Noise for Power Line Channel

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CHEN, Z.

2014-11-01

Full Text Available Impulse noise in power line communication (PLC channel seriously degrades the performance of Multiple-Input Multiple-Output (MIMO system. To remedy this problem, a MIMO detection method based on fractional lower order statistics (FLOS for PLC channel with impulse noise is proposed in this paper. The alpha stable distribution is used to model impulse noise, and FLOS is applied to construct the criteria of MIMO detection. Then the optimal detection solution is obtained by recursive least squares algorithm. Finally, the transmitted signals in PLC MIMO system are restored with the obtained detection matrix. The proposed method does not require channel estimation and has low computational complexity. The simulation results show that the proposed method has a better PLC MIMO detection performance than the existing ones under impulsive noise environment.

Nonparametric statistics a step-by-step approach

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Corder, Gregory W

2014-01-01

"…a very useful resource for courses in nonparametric statistics in which the emphasis is on applications rather than on theory.  It also deserves a place in libraries of all institutions where introductory statistics courses are taught."" -CHOICE This Second Edition presents a practical and understandable approach that enhances and expands the statistical toolset for readers. This book includes: New coverage of the sign test and the Kolmogorov-Smirnov two-sample test in an effort to offer a logical and natural progression to statistical powerSPSS® (Version 21) software and updated screen ca

Adrenal hypoplasia congenita: a rare cause of primary adrenal insufficiency and hypogonadotropic hypogonadism