Hard and soft tissue correlations in facial profiles: a canonical correlation study

Directory of Open Access Journals (Sweden)

Shamlan MA

2015-01-01

Full Text Available Manal A Shamlan,1 Abdullah M Aldrees2 1Faculty of Dentistry, King Abdulaziz University, Jeddah, 2Division of Orthodontics, Department of Pediatric Dentistry and Orthodontics, College of Dentistry, King Saud University, Riyadh, Saudi Arabia Background: The purpose of this study was to analyze the relationship between facial hard and soft tissues in normal Saudi individuals by studying the canonical correlation between specific hard tissue landmarks and their corresponding soft tissue landmarks. Methods: A retrospective, cross-sectional study was designed, with a sample size of 60 Saudi adults (30 males and 30 females who had a class I skeletal and dental relationship and normal occlusion. Lateral cephalometric radiographs of the study sample were investigated using a series of 29 linear and angular measurements of hard and soft tissue features. The measurements were calculated electronically using Dolphin® software, and the data were analyzed using canonical correlation. Results: Eighty-four percent of the variation in the soft tissue was explained by the variation in hard tissue. Conclusion: The position of the upper and lower incisors and inclination of the lower incisors influence upper lip length and lower lip position. The inclination of the upper incisors is associated with lower lip length. Keywords: facial profile, hard tissue, soft tissue, canonical correlation

Study habit skills as correlate of academic performance of ...

African Journals Online (AJOL)

Study habit is one of the major factors that could influence students' academic attainment. Thus, this study examined study habit skills as correlate of academic performance of undergraduates in Edo state, Nigeria. It employed a correlation research design, using multistage sampling technique. Two hundred and forty eight ...

Cross-correlation redshift calibration without spectroscopic calibration samples in DES Science Verification Data

Science.gov (United States)

Davis, C.; Rozo, E.; Roodman, A.; Alarcon, A.; Cawthon, R.; Gatti, M.; Lin, H.; Miquel, R.; Rykoff, E. S.; Troxel, M. A.; Vielzeuf, P.; Abbott, T. M. C.; Abdalla, F. B.; Allam, S.; Annis, J.; Bechtol, K.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Castander, F. J.; Crocce, M.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; Desai, S.; Diehl, H. T.; Doel, P.; Drlica-Wagner, A.; Fausti Neto, A.; Flaugher, B.; Fosalba, P.; Frieman, J.; García-Bellido, J.; Gaztanaga, E.; Gerdes, D. W.; Giannantonio, T.; Gruen, D.; Gruendl, R. A.; Gutierrez, G.; Honscheid, K.; Jain, B.; James, D. J.; Jeltema, T.; Krause, E.; Kuehn, K.; Kuhlmann, S.; Kuropatkin, N.; Lahav, O.; Li, T. S.; Lima, M.; March, M.; Marshall, J. L.; Martini, P.; Melchior, P.; Ogando, R. L. C.; Plazas, A. A.; Romer, A. K.; Sanchez, E.; Scarpine, V.; Schindler, R.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, M.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; Vikram, V.; Walker, A. R.; Wechsler, R. H.

2018-06-01

Galaxy cross-correlations with high-fidelity redshift samples hold the potential to precisely calibrate systematic photometric redshift uncertainties arising from the unavailability of complete and representative training and validation samples of galaxies. However, application of this technique in the Dark Energy Survey (DES) is hampered by the relatively low number density, small area, and modest redshift overlap between photometric and spectroscopic samples. We propose instead using photometric catalogues with reliable photometric redshifts for photo-z calibration via cross-correlations. We verify the viability of our proposal using redMaPPer clusters from the Sloan Digital Sky Survey (SDSS) to successfully recover the redshift distribution of SDSS spectroscopic galaxies. We demonstrate how to combine photo-z with cross-correlation data to calibrate photometric redshift biases while marginalizing over possible clustering bias evolution in either the calibration or unknown photometric samples. We apply our method to DES Science Verification (DES SV) data in order to constrain the photometric redshift distribution of a galaxy sample selected for weak lensing studies, constraining the mean of the tomographic redshift distributions to a statistical uncertainty of Δz ˜ ±0.01. We forecast that our proposal can, in principle, control photometric redshift uncertainties in DES weak lensing experiments at a level near the intrinsic statistical noise of the experiment over the range of redshifts where redMaPPer clusters are available. Our results provide strong motivation to launch a programme to fully characterize the systematic errors from bias evolution and photo-z shapes in our calibration procedure.

Simulating quantum correlations as a distributed sampling problem

International Nuclear Information System (INIS)

Degorre, Julien; Laplante, Sophie; Roland, Jeremie

2005-01-01

It is known that quantum correlations exhibited by a maximally entangled qubit pair can be simulated with the help of shared randomness, supplemented with additional resources, such as communication, postselection or nonlocal boxes. For instance, in the case of projective measurements, it is possible to solve this problem with protocols using one bit of communication or making one use of a nonlocal box. We show that this problem reduces to a distributed sampling problem. We give a new method to obtain samples from a biased distribution, starting with shared random variables following a uniform distribution, and use it to build distributed sampling protocols. This approach allows us to derive, in a simpler and unified way, many existing protocols for projective measurements, and extend them to positive operator value measurements. Moreover, this approach naturally leads to a local hidden variable model for Werner states

Comparison between correlated sampling and the perturbation technique of MCNP5 for fixed-source problems

International Nuclear Information System (INIS)

He Tao; Su Bingjing

2011-01-01

Highlights: → The performance of the MCNP differential operator perturbation technique is compared with that of the MCNP correlated sampling method for three types of fixed-source problems. → In terms of precision, the MCNP perturbation technique outperforms correlated sampling for one type of problem but performs comparably with or even under-performs correlated sampling for the other two types of problems. → In terms of accuracy, the MCNP perturbation calculations may predict inaccurate results for some of the test problems. However, the accuracy can be improved if the midpoint correction technique is used. - Abstract: Correlated sampling and the differential operator perturbation technique are two methods that enable MCNP (Monte Carlo N-Particle) to simulate small response change between an original system and a perturbed system. In this work the performance of the MCNP differential operator perturbation technique is compared with that of the MCNP correlated sampling method for three types of fixed-source problems. In terms of precision of predicted response changes, the MCNP perturbation technique outperforms correlated sampling for the problem involving variation of nuclide concentrations in the same direction but performs comparably with or even underperforms correlated sampling for the other two types of problems that involve void or variation of nuclide concentrations in opposite directions. In terms of accuracy, the MCNP differential operator perturbation calculations may predict inaccurate results that deviate from the benchmarks well beyond their uncertainty ranges for some of the test problems. However, the accuracy of the MCNP differential operator perturbation can be improved if the midpoint correction technique is used.

Determining Sample Size for Accurate Estimation of the Squared Multiple Correlation Coefficient.

Science.gov (United States)

Algina, James; Olejnik, Stephen

2000-01-01

Discusses determining sample size for estimation of the squared multiple correlation coefficient and presents regression equations that permit determination of the sample size for estimating this parameter for up to 20 predictor variables. (SLD)

Correlated sampling added to the specific purpose Monte Carlo code McPNL for neutron lifetime log responses

International Nuclear Information System (INIS)

Mickael, M.; Verghese, K.; Gardner, R.P.

1989-01-01

The specific purpose neutron lifetime oil well logging simulation code, McPNL, has been rewritten for greater user-friendliness and faster execution. Correlated sampling has been added to the code to enable studies of relative changes in the tool response caused by environmental changes. The absolute responses calculated by the code have been benchmarked against laboratory test pit data. The relative responses from correlated sampling are not directly benchmarked, but they are validated using experimental and theoretical results

Evaluation of correlation between physical properties and ultrasonic pulse velocity of fired clay samples.

Science.gov (United States)

Özkan, İlker; Yayla, Zeliha

2016-03-01

The aim of this study is to establish a correlation between physical properties and ultrasonic pulse velocity of clay samples fired at elevated temperatures. Brick-making clay and pottery clay were studied for this purpose. The physical properties of clay samples were assessed after firing pressed clay samples separately at temperatures of 850, 900, 950, 1000, 1050 and 1100 °C. A commercial ultrasonic testing instrument (Proceq Pundit Lab) was used to evaluate the ultrasonic pulse velocity measurements for each fired clay sample as a function of temperature. It was observed that there became a relationship between physical properties and ultrasonic pulse velocities of the samples. The results showed that in consequence of increasing densification of the samples, the differences between the ultrasonic pulse velocities were higher with increasing temperature. These findings may facilitate the use of ultrasonic pulse velocity for the estimation of physical properties of fired clay samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Evaluation of Approaches to Analyzing Continuous Correlated Eye Data When Sample Size Is Small.

Science.gov (United States)

Huang, Jing; Huang, Jiayan; Chen, Yong; Ying, Gui-Shuang

2018-02-01

To evaluate the performance of commonly used statistical methods for analyzing continuous correlated eye data when sample size is small. We simulated correlated continuous data from two designs: (1) two eyes of a subject in two comparison groups; (2) two eyes of a subject in the same comparison group, under various sample size (5-50), inter-eye correlation (0-0.75) and effect size (0-0.8). Simulated data were analyzed using paired t-test, two sample t-test, Wald test and score test using the generalized estimating equations (GEE) and F-test using linear mixed effects model (LMM). We compared type I error rates and statistical powers, and demonstrated analysis approaches through analyzing two real datasets. In design 1, paired t-test and LMM perform better than GEE, with nominal type 1 error rate and higher statistical power. In design 2, no test performs uniformly well: two sample t-test (average of two eyes or a random eye) achieves better control of type I error but yields lower statistical power. In both designs, the GEE Wald test inflates type I error rate and GEE score test has lower power. When sample size is small, some commonly used statistical methods do not perform well. Paired t-test and LMM perform best when two eyes of a subject are in two different comparison groups, and t-test using the average of two eyes performs best when the two eyes are in the same comparison group. When selecting the appropriate analysis approach the study design should be considered.

Monte Carlo burnup codes acceleration using the correlated sampling method

International Nuclear Information System (INIS)

Dieudonne, C.

2013-01-01

For several years, Monte Carlo burnup/depletion codes have appeared, which couple Monte Carlo codes to simulate the neutron transport to deterministic methods, which handle the medium depletion due to the neutron flux. Solving Boltzmann and Bateman equations in such a way allows to track fine 3-dimensional effects and to get rid of multi-group hypotheses done by deterministic solvers. The counterpart is the prohibitive calculation time due to the Monte Carlo solver called at each time step. In this document we present an original methodology to avoid the repetitive and time-expensive Monte Carlo simulations, and to replace them by perturbation calculations: indeed the different burnup steps may be seen as perturbations of the isotopic concentration of an initial Monte Carlo simulation. In a first time we will present this method, and provide details on the perturbative technique used, namely the correlated sampling. In a second time we develop a theoretical model to study the features of the correlated sampling method to understand its effects on depletion calculations. In a third time the implementation of this method in the TRIPOLI-4 code will be discussed, as well as the precise calculation scheme used to bring important speed-up of the depletion calculation. We will begin to validate and optimize the perturbed depletion scheme with the calculation of a REP-like fuel cell depletion. Then this technique will be used to calculate the depletion of a REP-like assembly, studied at beginning of its cycle. After having validated the method with a reference calculation we will show that it can speed-up by nearly an order of magnitude standard Monte-Carlo depletion codes. (author) [fr

Personality correlates of equity sensitivity for samples of Canadian, Bulgarian, and Mexican business people.

Science.gov (United States)

Mintu-Wimsatt, Alma; Madjourova-Davri, Anna; Lozada, Héctor R

2008-02-01

Equity sensitivity concerns perceptions of what is or is not equitable. Previous studies have shown that equity sensitivity is associated with one's relationship orientation. Relationships are also influenced by personality variables. As both personality and equity sensitivity influence relationships, equity sensitivity and personality may be correlated also; so, this study examined that possibility. The relations of equity sensitivity with 3 personality variables were explored across three culturally different samples. This allowed validation across cultures of the proposed equity-personality relationship which has traditionally been assessed in a U.S. setting. In general, personality-equity sensitivity relationship was not supported across the samples.

Correlations fo Sc, rare earths and other elements in selected rock samples from Arrua-i

Energy Technology Data Exchange (ETDEWEB)

Facetti, J F; Prats, M [Asuncion Nacional Univ. (Paraguay). Inst. de Ciencias

1972-01-01

The Sc and Eu contents in selected rocks samples from the stock of Arrua-i have been determined and correlations established with other elements and with the relative amount of some rare earths. These correlations suggest metasomatic phenomena for the formation of the rock samples.

Correlations fo Sc, rare earths and other elements in selected rock samples from Arrua-i

International Nuclear Information System (INIS)

Facetti, J.F.; Prats, M.

1972-01-01

The Sc and Eu contents in selected rocks samples from the stock of Arrua-i have been determined and correlations established with other elements and with the relative amount of some rare earths. These correlations suggest metasomatic phenomena for the formation of the rock samples

Time-dependent importance sampling in semiclassical initial value representation calculations for time correlation functions.

Science.gov (United States)

Tao, Guohua; Miller, William H

2011-07-14

An efficient time-dependent importance sampling method is developed for the Monte Carlo calculation of time correlation functions via the initial value representation (IVR) of semiclassical (SC) theory. A prefactor-free time-dependent sampling function weights the importance of a trajectory based on the magnitude of its contribution to the time correlation function, and global trial moves are used to facilitate the efficient sampling the phase space of initial conditions. The method can be generally applied to sampling rare events efficiently while avoiding being trapped in a local region of the phase space. Results presented in the paper for two system-bath models demonstrate the efficiency of this new importance sampling method for full SC-IVR calculations.

Correlation between k-space sampling pattern and MTF in compressed sensing MRSI.

Science.gov (United States)

Heikal, A A; Wachowicz, K; Fallone, B G

2016-10-01

To investigate the relationship between the k-space sampling patterns used for compressed sensing MR spectroscopic imaging (CS-MRSI) and the modulation transfer function (MTF) of the metabolite maps. This relationship may allow the desired frequency content of the metabolite maps to be quantitatively tailored when designing an undersampling pattern. Simulations of a phantom were used to calculate the MTF of Nyquist sampled (NS) 32 × 32 MRSI, and four-times undersampled CS-MRSI reconstructions. The dependence of the CS-MTF on the k-space sampling pattern was evaluated for three sets of k-space sampling patterns generated using different probability distribution functions (PDFs). CS-MTFs were also evaluated for three more sets of patterns generated using a modified algorithm where the sampling ratios are constrained to adhere to PDFs. Strong visual correlation as well as high R 2 was found between the MTF of CS-MRSI and the product of the frequency-dependant sampling ratio and the NS 32 × 32 MTF. Also, PDF-constrained sampling patterns led to higher reproducibility of the CS-MTF, and stronger correlations to the above-mentioned product. The relationship established in this work provides the user with a theoretical solution for the MTF of CS MRSI that is both predictable and customizable to the user's needs.

Local probe studies on lattice distortions and electronic correlations in manganites

CERN Document Server

lopes, Armandina; Correia, João Guilherme

This thesis presents an experimental study on lattice distortions and electronic correlations in colossal magnetoresistive magnetic oxides. The Perturbed Angular Correlation local probe technique is used to study selected manganite systems in order to obtain relevant insight into microscopic phenomena responsible for their macroscopic pr operties. Complementary structural, magnetic and electric characterization was performed. The work is focused on the following aspects: \\\\Lattice distortions and polaron clusters in LaMnO$_{3+ \\Delta}$ system. A study of the electric field gradi ent and magnetic hyperfine field was performed in representative samples of the LaMnO$_{3+ \\Delta}$ system, and correlated with macroscopic information obtained in the same samples. Particular attention was given to the LaMnO$_{3.12}$ sample since this compound is a prototype of a ferromagnetic-insulat or manganite, presenting a rhombohedric- orthorhombic structural phase transition near room temperature. We found that random distribu...

Comparison of correlation analysis techniques for irregularly sampled time series

Directory of Open Access Journals (Sweden)

K. Rehfeld

2011-06-01

Full Text Available Geoscientific measurements often provide time series with irregular time sampling, requiring either data reconstruction (interpolation or sophisticated methods to handle irregular sampling. We compare the linear interpolation technique and different approaches for analyzing the correlation functions and persistence of irregularly sampled time series, as Lomb-Scargle Fourier transformation and kernel-based methods. In a thorough benchmark test we investigate the performance of these techniques.

All methods have comparable root mean square errors (RMSEs for low skewness of the inter-observation time distribution. For high skewness, very irregular data, interpolation bias and RMSE increase strongly. We find a 40 % lower RMSE for the lag-1 autocorrelation function (ACF for the Gaussian kernel method vs. the linear interpolation scheme,in the analysis of highly irregular time series. For the cross correlation function (CCF the RMSE is then lower by 60 %. The application of the Lomb-Scargle technique gave results comparable to the kernel methods for the univariate, but poorer results in the bivariate case. Especially the high-frequency components of the signal, where classical methods show a strong bias in ACF and CCF magnitude, are preserved when using the kernel methods.

We illustrate the performances of interpolation vs. Gaussian kernel method by applying both to paleo-data from four locations, reflecting late Holocene Asian monsoon variability as derived from speleothem δ¹⁸O measurements. Cross correlation results are similar for both methods, which we attribute to the long time scales of the common variability. The persistence time (memory is strongly overestimated when using the standard, interpolation-based, approach. Hence, the Gaussian kernel is a reliable and more robust estimator with significant advantages compared to other techniques and suitable for large scale application to paleo-data.

Overweight and Obesity: Prevalence and Correlates in a Large Clinical Sample of Children with Autism Spectrum Disorder

Science.gov (United States)

Zuckerman, Katharine E.; Hill, Alison P.; Guion, Kimberly; Voltolina, Lisa; Fombonne, Eric

2014-01-01

Autism Spectrum Disorders (ASDs) and childhood obesity (OBY) are rising public health concerns. This study aimed to evaluate the prevalence of overweight (OWT) and OBY in a sample of 376 Oregon children with ASD, and to assess correlates of OWT and OBY in this sample. We used descriptive statistics, bivariate, and focused multivariate analyses to…

Health Correlates of Insomnia Symptoms and Comorbid Mental Disorders in a Nationally Representative Sample of US Adolescents

NARCIS (Netherlands)

Blank, M.; Zhang, J.H.; Lamers, F.; Taylor, A.D.; Hickie, I.B.; Merikangas, K.R.

2015-01-01

Study Objectives: To estimate the prevalence and health correlates of insomnia symptoms and their association with comorbid mental disorders in a nationally representative sample of adolescents in the United States. Design: National representative cross-sectional study. Setting: Population-based

Tailored two-photon correlation and fair-sampling: a cautionary tale

Science.gov (United States)

Romero, J.; Giovannini, D.; Tasca, D. S.; Barnett, S. M.; Padgett, M. J.

2013-08-01

We demonstrate an experimental test of the Clauser-Horne- Shimony-Holt (CHSH) Bell inequality which seemingly exhibits correlations beyond the limits imposed by quantum mechanics. Inspired by the idea of Fourier synthesis, we design analysers that measure specific superpositions of orbital angular momentum (OAM) states, such that when one analyser is rotated with respect to the other, the resulting coincidence curves are similar to a square-wave. Calculating the CHSH Bell parameter, S, from these curves result to values beyond the Tsirelson bound of S_{ {QM}}=2\\sqrt {2} . We obtain S = 3.99 ± 0.02, implying almost perfect nonlocal Popescu-Rohrlich correlations. The ‘super-quantum’ values of S is only possible in our experiment because our experiment, subtly, does not comply with fair-sampling. The way our Bell test fails fair-sampling is not immediately obvious and requires knowledge of the states being measured. Our experiment highlights the caution needed in Bell-type experiments based on measurements within high-dimensional state spaces such as that of OAM, especially in the advent of device-independent quantum protocols.

Autocorrelation and cross-correlation between hCGβ and PAPP-A in repeated sampling during first trimester of pregnancy

DEFF Research Database (Denmark)

Nørgaard, Pernille; Wright, Dave; Ball, Susan

2013-01-01

Theoretically, repeated sampling of free β-human chorionic gonadotropin (hCGβ) and pregnancy associated plasma protein-A (PAPP-A) in the first trimester of pregnancy might improve performance of risk assessment of trisomy 21 (T21). To assess the performance of a screening test involving repeated...... measures of biochemical markers, correlations between markers must be estimated. The aims of this study were to calculate the autocorrelation and cross-correlation between hCGβ and PAPP-A in the first trimester of pregnancy and to investigate the possible impact of gestational age at the first sample...

Analysis of reactor capital costs and correlated sampling of economic input variables - 15342

International Nuclear Information System (INIS)

Ganda, F.; Kim, T.K.; Taiwo, T.A.; Wigeland, R.

2015-01-01

In this paper we present work aimed at enhancing the capability to perform nuclear fuel cycle cost estimates and evaluation of financial risk. Reactor capital costs are of particular relevance, since they typically comprise about 60% to 70% of the calculated Levelized Cost of Electricity at Equilibrium (LCAE). The work starts with the collection of historical construction cost and construction duration of nuclear plants in the U.S. and France, as well as forecasted costs of nuclear plants currently under construction in the U.S. This data has the primary goal of supporting the introduction of an appropriate framework, supported in this paper by two case studies with historical data, which allows the development of solid and defensible assumptions on nuclear reactor capital costs. Work is also presented on the enhancement of the capability to model interdependence of cost estimates between facilities and uncertainties. The correlated sampling capabilities in the nuclear economic code NECOST have been expanded to include partial correlations between input variables, according to a given correlation matrix. Accounting for partial correlations correctly allows a narrowing, where appropriate, of the probability density function of the difference in the LCAE between alternative, but correlated, fuel cycles. It also allows the correct calculation of the standard deviation of the LCAE of multistage systems, which appears smaller than the correct value if correlated input costs are treated as uncorrelated. (authors)

Quantitating morphological changes in biological samples during scanning electron microscopy sample preparation with correlative super-resolution microscopy.

Science.gov (United States)

Zhang, Ying; Huang, Tao; Jorgens, Danielle M; Nickerson, Andrew; Lin, Li-Jung; Pelz, Joshua; Gray, Joe W; López, Claudia S; Nan, Xiaolin

2017-01-01

Sample preparation is critical to biological electron microscopy (EM), and there have been continuous efforts on optimizing the procedures to best preserve structures of interest in the sample. However, a quantitative characterization of the morphological changes associated with each step in EM sample preparation is currently lacking. Using correlative EM and superresolution microscopy (SRM), we have examined the effects of different drying methods as well as osmium tetroxide (OsO4) post-fixation on cell morphology during scanning electron microscopy (SEM) sample preparation. Here, SRM images of the sample acquired under hydrated conditions were used as a baseline for evaluating morphological changes as the sample went through SEM sample processing. We found that both chemical drying and critical point drying lead to a mild cellular boundary retraction of ~60 nm. Post-fixation by OsO4 causes at least 40 nm additional boundary retraction. We also found that coating coverslips with adhesion molecules such as fibronectin prior to cell plating helps reduce cell distortion from OsO4 post-fixation. These quantitative measurements offer useful information for identifying causes of cell distortions in SEM sample preparation and improving current procedures.

The Depressive Experiences Questionnaire: validity and psychological correlates in a clinical sample.

Science.gov (United States)

Riley, W T; McCranie, E W

1990-01-01

This study sought to compare the original and revised scoring systems of the Depressive Experiences Questionnaire (DEQ) and to assess the construct validity of the Dependent and Self-Critical subscales of the DEQ in a clinically depressed sample. Subjects were 103 depressed inpatients who completed the DEQ, the Beck Depression Inventory (BDI), the Hopelessness Scale, the Automatic Thoughts Questionnaire (ATQ), the Rathus Assertiveness Schedule (RAS), and the Minnesota Multiphasic Personality Inventory (MMPI). The original and revised scoring systems of the DEQ evidenced good concurrent validity for each factor scale, but the revised system did not sufficiently discriminate dependent and self-critical dimensions. Using the original scoring system, self-criticism was significantly and positively related to severity of depression, whereas dependency was not, particularly for males. Factor analysis of the DEQ scales and the other scales used in this study supported the dependent and self-critical dimensions. For men, the correlation of the DEQ with the MMPI scales indicated that self-criticism was associated with psychotic symptoms, hostility/conflict, and a distress/exaggerated response set, whereas dependency did not correlate significantly with any MMPI scales. Females, however, did not exhibit a differential pattern of correlations between either the Dependency or the Self-Criticism scales and the MMPI. These findings suggest possible gender differences in the clinical characteristics of male and female dependent and self-critical depressive subtypes.

CORRELATION ANALYSIS OF A LARGE SAMPLE OF NARROW-LINE SEYFERT 1 GALAXIES: LINKING CENTRAL ENGINE AND HOST PROPERTIES

International Nuclear Information System (INIS)

Xu Dawei; Komossa, S.; Wang Jing; Yuan Weimin; Zhou Hongyan; Lu Honglin; Li Cheng; Grupe, Dirk

2012-01-01

We present a statistical study of a large, homogeneously analyzed sample of narrow-line Seyfert 1 (NLS1) galaxies, accompanied by a comparison sample of broad-line Seyfert 1 (BLS1) galaxies. Optical emission-line and continuum properties are subjected to correlation analyses, in order to identify the main drivers of the correlation space of active galactic nuclei (AGNs), and of NLS1 galaxies in particular. For the first time, we have established the density of the narrow-line region as a key parameter in Eigenvector 1 space, as important as the Eddington ratio L/L Edd . This is important because it links the properties of the central engine with the properties of the host galaxy, i.e., the interstellar medium (ISM). We also confirm previously found correlations involving the line width of Hβ and the strength of the Fe II and [O III] λ5007 emission lines, and we confirm the important role played by L/L Edd in driving the properties of NLS1 galaxies. A spatial correlation analysis shows that large-scale environments of the BLS1 and NLS1 galaxies of our sample are similar. If mergers are rare in our sample, accretion-driven winds, on the one hand, or bar-driven inflows, on the other hand, may account for the strong dependence of Eigenvector 1 on ISM density.

Neuroanatomical correlates of time perspective: A voxel-based morphometry study.

Science.gov (United States)

Chen, Zhiyi; Guo, Yiqun; Feng, Tingyong

2018-02-26

Previous studies indicated that time perspective can affect many behaviors, such as decisions, risk taking, substance abuse and health behaviors. However, very little is known about the neural substrates of time perspective (TP). To address this question, we characterized different dimensions of TP (including the Past, Present, and Future TP) using standardized Zimbardo Time Perspective Inventory (ZTPI), and quantified the gray matter volume using voxel-based morphometry (VBM) method across two independent samples. Our whole-brain analysis (sample 1, N=150) revealed Past-Negative TP was positively correlated with the GMV of a cluster in LPFC whereas Past-Positive was negatively correlated with the GMV in OFC, and Future TP was negatively correlated with GMV in mPFC. Moreover, two present scales (Present-Hedonistic and Present-Fatalistic TPs) were positively correlated with the GMV of regions in MTG and precuneus, respectively. We further examined the reliability of these correlations between multidimensional TPs and neuroanatomical structures in another independent sample (sample 2, N=58). Results verified our findings that GMV in LPFC could predict Past-Negative TP while GMV in OFC could predict Past-Positive TP, and the GMV in MTG could predict Present-Hedonistic while the GMV in presuneus could predict Present-Fatalistic, as well as the GMV in mPFC could predict Future TP. Thus, our findings suggest that the existence of selective neural basis underlying TPs, and further provide the stable biomarkers for multidimensional TPs. Copyright © 2017 Elsevier B.V. All rights reserved.

Publication Bias in Psychology: A Diagnosis Based on the Correlation between Effect Size and Sample Size

Science.gov (United States)

Kühberger, Anton; Fritz, Astrid; Scherndl, Thomas

2014-01-01

Background The p value obtained from a significance test provides no information about the magnitude or importance of the underlying phenomenon. Therefore, additional reporting of effect size is often recommended. Effect sizes are theoretically independent from sample size. Yet this may not hold true empirically: non-independence could indicate publication bias. Methods We investigate whether effect size is independent from sample size in psychological research. We randomly sampled 1,000 psychological articles from all areas of psychological research. We extracted p values, effect sizes, and sample sizes of all empirical papers, and calculated the correlation between effect size and sample size, and investigated the distribution of p values. Results We found a negative correlation of r = −.45 [95% CI: −.53; −.35] between effect size and sample size. In addition, we found an inordinately high number of p values just passing the boundary of significance. Additional data showed that neither implicit nor explicit power analysis could account for this pattern of findings. Conclusion The negative correlation between effect size and samples size, and the biased distribution of p values indicate pervasive publication bias in the entire field of psychology. PMID:25192357

CT in the staging of bronchogenic carcinoma: Analysis by correlative lymph node mapping and sampling

International Nuclear Information System (INIS)

McLoud, T.C.; Woldenberg, R.; Mathisen, D.J.; Grillo, H.C.; Bourgoulin, P.M.; Shepard, J.O.; Moore, E.H.

1987-01-01

Although previous studies have evaluated the accuracy of CT in staging the mediastinum in bronchogenic carcinoma, none has determined the sensitivity and specificity of CT in the assessment of individual lymph node groups by correlative nodal sampling at surgery. CT scans were performed on 84 patients with bronchogenic carcinoma. Abnormal nodes (≥ 1 cm) were localized according to the ATS classification of regional lymph node mapping. Seventy-nine patients had mediastinoscopy and 64 patients underwent thoracotomy. In each case, biopsies of lymph node groups 2R, 4R, 2L, 4L (paratracheal), 7 (subcarinal), and 5 (aorticopulmonary) were performed on the appropriate side. Hilar nodes (10R and 11R, 10L and 11L) were resected with the surgical specimen. A total of 292 nodes were sampled. Overall sensitivity for all lymph node groups was 40%, and specificity, 81%. Sensitivity was highest for the 4R (paratracheal) group (82%) and lowest for the subcarinal area (20%). Specificity ranged from 71% for 11R nodes (right hilar) to 94% for 10L (left peribronchial). The positive predictive value was 34%, and the negative predictive value, 84%. This study suggests that the more optimistic results previously reported may have resulted from lack of correlation of individual lymph node groups identified on CT with those sampled at surgery

Quantum Correlations in Nonlocal Boson Sampling.

Science.gov (United States)

Shahandeh, Farid; Lund, Austin P; Ralph, Timothy C

2017-09-22

Determination of the quantum nature of correlations between two spatially separated systems plays a crucial role in quantum information science. Of particular interest is the questions of if and how these correlations enable quantum information protocols to be more powerful. Here, we report on a distributed quantum computation protocol in which the input and output quantum states are considered to be classically correlated in quantum informatics. Nevertheless, we show that the correlations between the outcomes of the measurements on the output state cannot be efficiently simulated using classical algorithms. Crucially, at the same time, local measurement outcomes can be efficiently simulated on classical computers. We show that the only known classicality criterion violated by the input and output states in our protocol is the one used in quantum optics, namely, phase-space nonclassicality. As a result, we argue that the global phase-space nonclassicality inherent within the output state of our protocol represents true quantum correlations.

Personality and attitudinal correlates of meat consumption: Results of two representative German samples.

Science.gov (United States)

Pfeiler, Tamara M; Egloff, Boris

2018-02-01

The vast amount of meat consumed in the Western world is critically discussed with regard to negative health consequences, environmental impact, and ethical concerns for animals, emphasizing the need to extend knowledge regarding the correlates of meat consumption in the general population. In the present article, we conducted two studies examining the associations between meat consumption and personality traits, political attitudes, and environmental attitudes in two large German representative samples (N total  = 8,879, aged 18-96 years). Cross-sectional data on frequency of meat consumption, socio-demographics, personality traits, and political and environmental attitudes were collected via self-reports. In both studies, male sex, younger age, and lower educational attainment were significantly positively related to meat consumption. In Study 1, results of the partial correlations and the hierarchical regression analysis controlling for socio-demographics showed that the personality traits of openness and agreeableness, as well as conservative political and social views, explained unique variance in meat consumption. In Study 2, partial correlations and hierarchical regression analyses showed that openness, agreeableness, and conscientiousness were all uniquely negatively related to meat consumption. Moreover, these analyses documented that people scoring high in right-wing attitudes and low in pro-environmental attitudes reported more overall meat consumption. Taken together, these two studies provided evidence that socio-demographics, personality traits, and attitudes are indeed related to how much meat is consumed. Implications and future prospects for the study of individual differences in meat consumption are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Experimental study on deformation field evolution in rock sample with en echelon faults using digital speckle correlation method

Science.gov (United States)

Ma, S.; Ma, J.; Liu, L.; Liu, P.

2007-12-01

Digital speckle correlation method (DSCM) is one kind of photomechanical deformation measurement method. DSCM could obtain continuous deformation field contactlessly by just capturing speckle images from specimen surface. Therefore, it is suitable to observe high spatial resolution deformation field in tectonophysical experiment. However, in the general DSCM experiment, the inspected surface of specimen needs to be painted to bear speckle grains in order to obtain the high quality speckle image. This also affects the realization of other measurement techniques. In this study, an improved DSCM system is developed and utilized to measure deformation field of rock specimen without surface painting. The granodiorite with high contrast nature grains is chosen to manufacture the specimen, and a specially designed DSCM algorithm is developed to analyze this kind of nature speckle images. Verification and calibration experiments show that the system could inspect a continuous (about 15Hz) high resolution displacement field (with resolution of 5μm) and strain field (with resolution of 50μɛ), dispensing with any preparation on rock specimen. Therefore, it could be conveniently utilized to study the failure of rock structure. Samples with compressive en echelon faults and extensional en echelon faults are studied on a two-direction servo-control test machine. The failure process of the samples is discussed based on the DSCM results. Experiment results show that: 1) The contours of displacement field could clearly indicate the activities of faults and new cracks. The displacement gradient adjacent to active faults and cracks is much greater than other areas. 2) Before failure of the samples, the mean strain of the jog area is largest for the compressive en echelon fault, while that is smallest for the extensional en echelon fault. This consists with the understanding that the jog area of compressive fault subjects to compression and that of extensional fault subjects to

A covariance correction that accounts for correlation estimation to improve finite-sample inference with generalized estimating equations: A study on its applicability with structured correlation matrices.

Science.gov (United States)

Westgate, Philip M

2016-01-01

When generalized estimating equations (GEE) incorporate an unstructured working correlation matrix, the variances of regression parameter estimates can inflate due to the estimation of the correlation parameters. In previous work, an approximation for this inflation that results in a corrected version of the sandwich formula for the covariance matrix of regression parameter estimates was derived. Use of this correction for correlation structure selection also reduces the over-selection of the unstructured working correlation matrix. In this manuscript, we conduct a simulation study to demonstrate that an increase in variances of regression parameter estimates can occur when GEE incorporates structured working correlation matrices as well. Correspondingly, we show the ability of the corrected version of the sandwich formula to improve the validity of inference and correlation structure selection. We also study the relative influences of two popular corrections to a different source of bias in the empirical sandwich covariance estimator.

Distribution of the Determinant of the Sample Correlation Matrix: Monte Carlo Type One Error Rates.

Science.gov (United States)

Reddon, John R.; And Others

1985-01-01

Computer sampling from a multivariate normal spherical population was used to evaluate the type one error rates for a test of sphericity based on the distribution of the determinant of the sample correlation matrix. (Author/LMO)

Correlation between chemical composition of dental calculus and bone samples in ancient human burials: perspectives in paleonutritional studies

International Nuclear Information System (INIS)

Capasso, L.; Di Tota, G.; Bondioli, L.

1997-01-01

Full text: The authors describe the results of an assay based on the comparison between chemical composition of dental calculus and bone respectively obtained from teeth and bones of ancient skeletons. The chemical analysis has been performed by synchrotron light. The concentrations of the following oligoelements having paleonutritional correlations were analysed: Fe, Cu, Zn, Pb, Sr and Ca. The authors demonstrate that- in a given individual the concentration of such elements in the bone sample were in the range of those obtained for the same elements in the sample of dental calculus. Such correspondence suggests that the chemical analysis of dental calculus may give paleonutritional indications analogous to those deriving from the analysis of bone samples. The authors underline also that the use of dental calculus has a distinct advantage over the use of bone samples, since it may allow a diachronic investigation. In fact, dental calculus typically presents a concentric pattern of growth, and the chemical composition of each layer may vary in accordance with temporal dietary variations. This is not the case for bone. This fact is the theoretical basis for the possible future development of techniques directed to the reconstruction of variations in the dietary habits of ancient individuals, possibly in relation to environmental seasonal changes

Power-law correlations and finite-size effects in silica particle aggregates studied by small-angle neutron scattering

DEFF Research Database (Denmark)

Freltoft, T.; Kjems, Jørgen; Sinha, S. K.

1986-01-01

Small-angle neutron scattering from normal, compressed, and water-suspended powders of aggregates of fine silica particles has been studied. The samples possessed average densities ranging from 0.008 to 0.45 g/cm3. Assuming power-law correlations between particles and a finite correlation length ξ......, the authors derive the scattering function S(q) from specific models for particle-particle correlation in these systems. S(q) was found to provide a satisfactory fit to the data for all samples studied. The fractal dimension df corresponding to the power-law correlation was 2.61±0.1 for all dry samples, and 2...

A Correlational Study Examining Demonstrated Emotional Intelligence and Perceptions of School Climate

Science.gov (United States)

Anderson, Chris James

2016-01-01

A quantitative study with a correlational design, this research investigated whether certified teachers' ratings of their school leader's demonstrated emotional intelligence behaviors correlated with the teacher's perceptions of school climate. A sample of 42 graduate and post baccalaureate students from a Mid-Atlantic region college accessed a…

Degradation of metallic materials studied by correlative tomography

Science.gov (United States)

Burnett, T. L.; Holroyd, N. J. H.; Lewandowski, J. J.; Ogurreck, M.; Rau, C.; Kelley, R.; Pickering, E. J.; Daly, M.; Sherry, A. H.; Pawar, S.; Slater, T. J. A.; Withers, P. J.

2017-07-01

There are a huge array of characterization techniques available today and increasingly powerful computing resources allowing for the effective analysis and modelling of large datasets. However, each experimental and modelling tool only spans limited time and length scales. Correlative tomography can be thought of as the extension of correlative microscopy into three dimensions connecting different techniques, each providing different types of information, or covering different time or length scales. Here the focus is on the linking of time lapse X-ray computed tomography (CT) and serial section electron tomography using the focussed ion beam (FIB)-scanning electron microscope to study the degradation of metals. Correlative tomography can provide new levels of detail by delivering a multiscale 3D picture of key regions of interest. Specifically, the Xe+ Plasma FIB is used as an enabling tool for large-volume high-resolution serial sectioning of materials, and also as a tool for preparation of microscale test samples and samples for nanoscale X-ray CT imaging. The exemplars presented illustrate general aspects relating to correlative workflows, as well as to the time-lapse characterisation of metal microstructures during various failure mechanisms, including ductile fracture of steel and the corrosion of aluminium and magnesium alloys. Correlative tomography is already providing significant insights into materials behaviour, linking together information from different instruments across different scales. Multiscale and multifaceted work flows will become increasingly routine, providing a feed into multiscale materials models as well as illuminating other areas, particularly where hierarchical structures are of interest.

Study of morphological changes in scattering and optically anisotropic medium through correlation images

Science.gov (United States)

Jain, Neha; Shukla, Prashant; Singh, Jai

2018-05-01

Correlation images are very useful in determining the morphological changes. We have investigated the correlation image analysis on depolarization and retardance matrices of polystyrene and gelatine samples respectively. We observed that that correlation images have a potential to show a significant variation with change in the concentration of samples (polystyrene and gelatine). For polystyrene microspheres the correlation value decreases with increasing scattering coefficient. In gelatine samples the correlation also decreases with sample concentration. This variation in correlation for retardance shows the change in a birefringence property of gelatine solution.

Trait correlates of relational aggression in a nonclinical sample: DSM-IV personality disorders and psychopathy.

Science.gov (United States)

Schmeelk, Kelly M; Sylvers, Patrick; Lilienfeld, Scott O

2008-06-01

The implications of adult relational aggression in adults for personality pathology are poorly understood. We investigated the association between relational aggression and features of DSM-IV personality disorders and psychopathy in a sample of undergraduates (N = 220). In contrast to the childhood literature, we found no significant difference in relational aggression between men and women. Unlike overt aggression, which correlated about equally highly with features of all three personality disorder clusters, relational aggression correlated significantly more highly with features of Cluster B than Clusters A or C. In addition, even after controlling for overt aggression, relational aggression correlated significantly with features of psychopathy, although only with Factor 2 traits. With the exception of sadistic personality disorder features, gender did not moderate the relationship between relational aggression and personality pathology. Further research on the psycho-pathological implications of relational aggression in more severely affected samples is warranted.

A Study on Physical Education Teachers: The Correlation between Self-Efficacy and Job Satisfaction

Science.gov (United States)

Yildirim, Irfan

2015-01-01

The aim of the study was to determine the correlation between self-efficacy and job satisfaction among the physical education teachers. The study was carried out in correlational survey model and the study sample was made up by 306 physical education teachers who worked in different geographical regions of Turkey. The data were assessed using SPSS…

Correlates of homophobia, transphobia, and internalized homophobia in gay or lesbian and heterosexual samples.

Science.gov (United States)

Warriner, Katrina; Nagoshi, Craig T; Nagoshi, Julie L

2013-01-01

This research assessed the correlates of homophobia and transphobia in heterosexual and homosexual individuals, based on a theory of different sources of perceived symbolic threat to social status. Compared to 310 heterosexual college students, a sample of 30 gay male and 30 lesbian college students scored lower on homophobia, transphobia, and religious fundamentalism. Mean gender differences were smaller for gay men and lesbians for homophobia, aggressiveness, benevolent sexism, masculinity, and femininity. Fundamentalism, right-wing authoritarianism, and hostile and benevolent sexism were correlated only with homophobia in lesbians, whereas fundamentalism and authoritarianism were correlated only with transphobia in gay men. Correlates of internalized homophobia were different than those found for homophobia and transphobia, which was discussed in terms of gender differences in threats to status based on sexual orientation versus gender identity.

Sample-averaged biexciton quantum yield measured by solution-phase photon correlation.

Science.gov (United States)

Beyler, Andrew P; Bischof, Thomas S; Cui, Jian; Coropceanu, Igor; Harris, Daniel K; Bawendi, Moungi G

2014-12-10

The brightness of nanoscale optical materials such as semiconductor nanocrystals is currently limited in high excitation flux applications by inefficient multiexciton fluorescence. We have devised a solution-phase photon correlation measurement that can conveniently and reliably measure the average biexciton-to-exciton quantum yield ratio of an entire sample without user selection bias. This technique can be used to investigate the multiexciton recombination dynamics of a broad scope of synthetically underdeveloped materials, including those with low exciton quantum yields and poor fluorescence stability. Here, we have applied this method to measure weak biexciton fluorescence in samples of visible-emitting InP/ZnS and InAs/ZnS core/shell nanocrystals, and to demonstrate that a rapid CdS shell growth procedure can markedly increase the biexciton fluorescence of CdSe nanocrystals.

Viewing child pornography: prevalence and correlates in a representative community sample of young Swedish men.

Science.gov (United States)

Seto, Michael C; Hermann, Chantal A; Kjellgren, Cecilia; Priebe, Gisela; Svedin, Carl Göran; Långström, Niklas

2015-01-01

Most research on child pornography use has been based on selected clinical or criminal justice samples; risk factors for child pornography use in the general population remain largely unexplored. In this study, we examined prevalence, risk factors, and correlates of viewing depictions of adult-child sex in a population-representative sample of 1,978 young Swedish men (17-20 years, Mdn = 18 years, overall response rate, 77 %). In an anonymous, school-based survey, participants self-reported sexual coercion experiences, attitudes and beliefs about sex, perceived peer attitudes, and sexual interests and behaviors; including pornography use, sexual interest in children, and sexually coercive behavior. A total of 84 (4.2 %) young men reported they had ever viewed child pornography. Most theory-based variables were moderately and significantly associated with child pornography viewing and were consistent with models of sexual offending implicating both antisociality and sexual deviance. In multivariate logistic regression analysis, 7 of 15 tested factors independently predicted child pornography viewing and explained 42 % of the variance: ever had sex with a male, likely to have sex with a child aged 12-14, likely to have sex with a child 12 or less, perception of children as seductive, having friends who have watched child pornography, frequent pornography use, and ever viewed violent pornography. From these, a 6-item Child Pornography Correlates Scale was constructed and then cross-validated in a similar but independent Norwegian sample.

Sample Size Calculation for Estimating or Testing a Nonzero Squared Multiple Correlation Coefficient

Science.gov (United States)

Krishnamoorthy, K.; Xia, Yanping

2008-01-01

The problems of hypothesis testing and interval estimation of the squared multiple correlation coefficient of a multivariate normal distribution are considered. It is shown that available one-sided tests are uniformly most powerful, and the one-sided confidence intervals are uniformly most accurate. An exact method of calculating sample size to…

Analysis of uranium and its correlation with some physico-chemical properties of drinking water samples from Amritsar, Punjab.

Science.gov (United States)

Singh, Surinder; Rani, Asha; Mahajan, Rakesh Kumar; Walia, Tejinder Pal Singh

2003-12-01

Fission track technique has been used for uranium estimation in drinking water samples collected from some areas of Amritsar District, Punjab, India. The uranium concentration in water samples is found to vary from 3.19 to 45.59 microg l(-1). Some of the physico-chemical properties such as pH, conductance and hardness and the content of calcium, magnesium, total dissolved solids (TDS), sodium, potassium, chloride, nitrate and heavy metals viz. zinc, cadmium, lead and copper have been determined in water samples. An attempt has been made to correlate uranium concentration with these water quality parameters. A positive correlation of conductance, nitrate, chloride, sodium, potassium, magnesium, TDS, calcium and hardness with uranium concentration has been observed. However, no correlation has been observed between the concentration of uranium and the heavy metals analysed.

On the Analysis of Case-Control Studies in Cluster-correlated Data Settings.

Science.gov (United States)

Haneuse, Sebastien; Rivera-Rodriguez, Claudia

2018-01-01

In resource-limited settings, long-term evaluation of national antiretroviral treatment (ART) programs often relies on aggregated data, the analysis of which may be subject to ecological bias. As researchers and policy makers consider evaluating individual-level outcomes such as treatment adherence or mortality, the well-known case-control design is appealing in that it provides efficiency gains over random sampling. In the context that motivates this article, valid estimation and inference requires acknowledging any clustering, although, to our knowledge, no statistical methods have been published for the analysis of case-control data for which the underlying population exhibits clustering. Furthermore, in the specific context of an ongoing collaboration in Malawi, rather than performing case-control sampling across all clinics, case-control sampling within clinics has been suggested as a more practical strategy. To our knowledge, although similar outcome-dependent sampling schemes have been described in the literature, a case-control design specific to correlated data settings is new. In this article, we describe this design, discuss balanced versus unbalanced sampling techniques, and provide a general approach to analyzing case-control studies in cluster-correlated settings based on inverse probability-weighted generalized estimating equations. Inference is based on a robust sandwich estimator with correlation parameters estimated to ensure appropriate accounting of the outcome-dependent sampling scheme. We conduct comprehensive simulations, based in part on real data on a sample of N = 78,155 program registrants in Malawi between 2005 and 2007, to evaluate small-sample operating characteristics and potential trade-offs associated with standard case-control sampling or when case-control sampling is performed within clusters.

A Quantitative Correlational Study of Teacher Preparation Program on Student Achievement

Science.gov (United States)

Dingman, Jacob Blackstone

2010-01-01

The purpose of this quantitative correlational study was to identify the relationship between the type of teacher preparation program and student performance on the seventh and eighth grade mathematics state assessments in rural school settings. The study included a survey of a convenience sample of 36 teachers from Colorado and Washington school…

Effect of Malmquist bias on correlation studies with IRAS data base

Science.gov (United States)

Verter, Frances

1993-01-01

The relationships between galaxy properties in the sample of Trinchieri et al. (1989) are reexamined with corrections for Malmquist bias. The linear correlations are tested and linear regressions are fit for log-log plots of L(FIR), L(H-alpha), and L(B) as well as ratios of these quantities. The linear correlations for Malmquist bias are corrected using the method of Verter (1988), in which each galaxy observation is weighted by the inverse of its sampling volume. The linear regressions are corrected for Malmquist bias by a new method invented here in which each galaxy observation is weighted by its sampling volume. The results of correlation and regressions among the sample are significantly changed in the anticipated sense that the corrected correlation confidences are lower and the corrected slopes of the linear regressions are lower. The elimination of Malmquist bias eliminates the nonlinear rise in luminosity that has caused some authors to hypothesize additional components of FIR emission.

The correlation between selenium adsorption and the mineral and chemical composition of Taiwan local granite samples

Energy Technology Data Exchange (ETDEWEB)

Wang, TsingHai; Chiang, Chu-Ling; Wang, Chu-Fang [National Tsing Hua Univ., Hsinchu, Taiwan (China). Biomedical Engineering and Environmental Sciences

2015-07-01

Selenium-79 (Se-79) is a radioactive isotope of selenium, which is considered as one of the highly mobile nuclides since Se-79 would be presented in an anion species when dissolving into the intruded groundwater. Being an anionic species, the transport of Se-79 would be regulated by the metal oxides relevant minerals such as goethite and hematite (Jan et al., 2008). This is true that the transport of selenium in the shallow surface environment could be relatively easy to estimate by considering the amount of these metal oxides presenting in the soils and sediments. However, when dealing with deep geological repository, the transport of Se-79 becomes less predictable because of the much less content of metal oxide residing in the host rock such as granite. In order to conduct a reliable performance assessment of repository, it is very important to establish the correlation between selenium adsorption and the properties of potential host rock, in this study, the mineral and chemical compositions of Taiwan local granite. From this point of view, selenium adsorption experiments were conducted with 54 different Taiwan local granite samples collected from the depth ranging from 100 ∝ 400 meters below the surface. These granite samples represent a variety of deep geological environments, including the intact rock, groundwater intruded zones, and some weathered samples. Based upon our preliminary results, several solid conclusions could be made. First, the correlation coefficients between the Kd values and the mineral and chemical compositions are rather low (R-square values are often < 0.2). This points out the complexity of these geological samples and strongly suggests more efforts should be put into to acquire more relevant information. Second, the correlation between the selenium Kd values and the content of iron oxide (R-square 0.110) is much higher than that between the CEC of these granite samples (R-square 0.001). This clearly indicates that the minerals that

Is meat quality from Longissimus lumborum samples correlated with other cuts in horse meat?

Science.gov (United States)

De Palo, Pasquale; Maggiolino, Aristide; Centoducati, Pasquale; Milella, Paola; Calzaretti, Giovanna; Tateo, Alessandra

2016-03-01

The present work aims to investigate if the variation of each parameter in Longissimus lumborum muscle could correspond to the same or to a similar variation of the parameter in the other muscles. The work presents results of Pearson's correlations between Longissimus lumborum samples and other muscle samples, such as Biceps femoris, Rectus femoris, Semimembranosus, Supraspinatus and Semitendinosus in horse meat. A total of 27 male IHDH (Italian Heavy Draught Horse) breed foals were employed. They were slaughtered at 11 months of age and the above-mentioned muscles were sampled. The Longissimus lumborum muscle showed to be representative of other muscles and of the whole carcass for some chemical parameters (moisture, protein and ash) and for some fatty acids profile patterns such as C12:0, C14:0, total monounsaturated fatty acid and polyunsaturated fatty acid, but poor correlations were recorded for intramuscular fat concentration, rheological and colorimetric parameters. Although almost all the qualitative parameters in meat are affected by the anatomical site and by the muscle, the Longissimus lumborum is often not representative in horse meat with regard to modifications of this parameters. © 2015 Japanese Society of Animal Science.

Reliability of environmental sampling culture results using the negative binomial intraclass correlation coefficient.

Science.gov (United States)

Aly, Sharif S; Zhao, Jianyang; Li, Ben; Jiang, Jiming

2014-01-01

The Intraclass Correlation Coefficient (ICC) is commonly used to estimate the similarity between quantitative measures obtained from different sources. Overdispersed data is traditionally transformed so that linear mixed model (LMM) based ICC can be estimated. A common transformation used is the natural logarithm. The reliability of environmental sampling of fecal slurry on freestall pens has been estimated for Mycobacterium avium subsp. paratuberculosis using the natural logarithm transformed culture results. Recently, the negative binomial ICC was defined based on a generalized linear mixed model for negative binomial distributed data. The current study reports on the negative binomial ICC estimate which includes fixed effects using culture results of environmental samples. Simulations using a wide variety of inputs and negative binomial distribution parameters (r; p) showed better performance of the new negative binomial ICC compared to the ICC based on LMM even when negative binomial data was logarithm, and square root transformed. A second comparison that targeted a wider range of ICC values showed that the mean of estimated ICC closely approximated the true ICC.

A method for the estimation of the significance of cross-correlations in unevenly sampled red-noise time series

Science.gov (United States)

Max-Moerbeck, W.; Richards, J. L.; Hovatta, T.; Pavlidou, V.; Pearson, T. J.; Readhead, A. C. S.

2014-11-01

We present a practical implementation of a Monte Carlo method to estimate the significance of cross-correlations in unevenly sampled time series of data, whose statistical properties are modelled with a simple power-law power spectral density. This implementation builds on published methods; we introduce a number of improvements in the normalization of the cross-correlation function estimate and a bootstrap method for estimating the significance of the cross-correlations. A closely related matter is the estimation of a model for the light curves, which is critical for the significance estimates. We present a graphical and quantitative demonstration that uses simulations to show how common it is to get high cross-correlations for unrelated light curves with steep power spectral densities. This demonstration highlights the dangers of interpreting them as signs of a physical connection. We show that by using interpolation and the Hanning sampling window function we are able to reduce the effects of red-noise leakage and to recover steep simple power-law power spectral densities. We also introduce the use of a Neyman construction for the estimation of the errors in the power-law index of the power spectral density. This method provides a consistent way to estimate the significance of cross-correlations in unevenly sampled time series of data.

Neutron Activation Analysis and Moessbauer Correlations of Archaeological Pottery from Amazon Basin for Classification Studies

International Nuclear Information System (INIS)

Bellido, A. V. B.; Latini, R. M.; Nicoli, I.; Scorzelli, R. B.; Solorzano, P. M.

2011-01-01

The aim of the present work was to investigate the correlation between data obtained by means of two analytical methods, instrumental neutron activation analysis (INAA) and Moessbauer Spectroscopy of pottery samples combined with multivariate statistical analysis in order to optimize quantitative analysis in the classification studies. Ceramics recently discovered in archaeological earth circular structures sites in Acre state Brazil. 199 samples were analyzed by INAA, allowing simultaneous determination of twenty elements chemical concentrations, and 44 samples by using Moessbauer Spectroscopy, allowing the determination of fourteen hyperfine parameters. For the correlation study, data were treated by two multivariate statistical methods: cluster analysis for the classification and the principal component analysis for the data correlations. INAA data show that some of REE (rare earth elements) were the discriminating variables for this technique. Mossbauer parameters that exhibit the same behavior are being investigated, remarkable improve can be seem for the combined REE and the Mossbauer variables showing a good results considering the limited number of samples. This data matrix is being used for the understanding in the studies of classification and provenance of ceramics prehistory of the Amazonic basin.

Optimal CCD readout by digital correlated double sampling

Science.gov (United States)

Alessandri, C.; Abusleme, A.; Guzman, D.; Passalacqua, I.; Alvarez-Fontecilla, E.; Guarini, M.

2016-01-01

Digital correlated double sampling (DCDS), a readout technique for charge-coupled devices (CCD), is gaining popularity in astronomical applications. By using an oversampling ADC and a digital filter, a DCDS system can achieve a better performance than traditional analogue readout techniques at the expense of a more complex system analysis. Several attempts to analyse and optimize a DCDS system have been reported, but most of the work presented in the literature has been experimental. Some approximate analytical tools have been presented for independent parameters of the system, but the overall performance and trade-offs have not been yet modelled. Furthermore, there is disagreement among experimental results that cannot be explained by the analytical tools available. In this work, a theoretical analysis of a generic DCDS readout system is presented, including key aspects such as the signal conditioning stage, the ADC resolution, the sampling frequency and the digital filter implementation. By using a time-domain noise model, the effect of the digital filter is properly modelled as a discrete-time process, thus avoiding the imprecision of continuous-time approximations that have been used so far. As a result, an accurate, closed-form expression for the signal-to-noise ratio at the output of the readout system is reached. This expression can be easily optimized in order to meet a set of specifications for a given CCD, thus providing a systematic design methodology for an optimal readout system. Simulated results are presented to validate the theory, obtained with both time- and frequency-domain noise generation models for completeness.

Study of helminthiasis in pregnancy and its correlation with haemoglobin level.

Science.gov (United States)

K, Shrinivas; Radhika; R, Sreelatha; K, Kavitha

2014-10-01

To study types of worm infestation in pregnancy and to correlate helminthiasis with haemoglobin level in antenatal women presenting in 2nd and 3rd trimester. This prospective cross sectional hospital based study conducted at Vanivilas hospital attached to Bangalore medical college, over a period of sixmonths. Study included 500 pregnant women attending antenatal opd in 2nd and 3rd trimester, selected by systematic random sampling method. Parasitic examination and haemoglobin estimation done respectively with Stool and blood samples collected from study group. Presence of parasites was correlated with haemoglobin percentage. Helminthiasis was found in 62 women (12.4%). All infected women had single type helminth infection. Ascariasis was more commonly found than hookworm (10% Vs 2.4%). Anaemia of various degrees was found in 88.7% of women with helminthiasis as compared to 56.4% women without worm infestation (p-value Helminthiasis is a significant burden in pregnancy and it is associated with anaemia. Hence, the policy of universal administration of anthelminthic drug in pregnancy after first trimester, as recommended by WHO should be practically enforced besides health education.

A Correlational Study of iPad Efficacy and 21st Century Teaching among Elementary School Teachers

Science.gov (United States)

Shultz, Christopher F.

2017-01-01

This study was a longitudinal correlational study that applied the quantitative methodology of bi-variate correlation as well as a paired-samples "t"-test to the data. The purpose was to study the nature of the relationship between iPad efficacy, 21st century teaching, teacher efficacy, and teacher characteristics. The study also…

In-Situ Systematic Error Correction for Digital Volume Correlation Using a Reference Sample

KAUST Repository

Wang, B.

2017-11-27

The self-heating effect of a laboratory X-ray computed tomography (CT) scanner causes slight change in its imaging geometry, which induces translation and dilatation (i.e., artificial displacement and strain) in reconstructed volume images recorded at different times. To realize high-accuracy internal full-field deformation measurements using digital volume correlation (DVC), these artificial displacements and strains associated with unstable CT imaging must be eliminated. In this work, an effective and easily implemented reference sample compensation (RSC) method is proposed for in-situ systematic error correction in DVC. The proposed method utilizes a stationary reference sample, which is placed beside the test sample to record the artificial displacement fields caused by the self-heating effect of CT scanners. The detected displacement fields are then fitted by a parametric polynomial model, which is used to remove the unwanted artificial deformations in the test sample. Rescan tests of a stationary sample and real uniaxial compression tests performed on copper foam specimens demonstrate the accuracy, efficacy, and practicality of the presented RSC method.

In-Situ Systematic Error Correction for Digital Volume Correlation Using a Reference Sample

KAUST Repository

Wang, B.; Pan, B.; Lubineau, Gilles

2017-01-01

The self-heating effect of a laboratory X-ray computed tomography (CT) scanner causes slight change in its imaging geometry, which induces translation and dilatation (i.e., artificial displacement and strain) in reconstructed volume images recorded at different times. To realize high-accuracy internal full-field deformation measurements using digital volume correlation (DVC), these artificial displacements and strains associated with unstable CT imaging must be eliminated. In this work, an effective and easily implemented reference sample compensation (RSC) method is proposed for in-situ systematic error correction in DVC. The proposed method utilizes a stationary reference sample, which is placed beside the test sample to record the artificial displacement fields caused by the self-heating effect of CT scanners. The detected displacement fields are then fitted by a parametric polynomial model, which is used to remove the unwanted artificial deformations in the test sample. Rescan tests of a stationary sample and real uniaxial compression tests performed on copper foam specimens demonstrate the accuracy, efficacy, and practicality of the presented RSC method.

A Study of Correlation of Various Growth Indicators with Chronological Age.

Science.gov (United States)

Singh, Sarabjeet; Sandhu, Navreet; Puri, Taruna; Gulati, Ritika; Kashyap, Rita

2015-01-01

The aim of this study was to assess the relationship of chronological age with cervical vertebrae skeletal maturation, frontal sinus width and antegonial notch depth and a correlation, if any, among the three variables. The samples were derived from lateral cephalometric radiographs of 80 subjects (40 males, 40 females; age range: 10 to 19 years). Cervical vertebral development was evaluated by the method of Hassel and Farman, frontal sinus width was measured by the method described by Ertürk and antegonial notch depth as described by Singer et al. The Pearson's correlation coefficients were estimated to assess the relationship of chronological age with cervical vertebrae skeletal maturation, frontal sinus width and antegonial notch depth. The Pearson's correlation coefficient were 0.855 (p correlation was found between chronological age and cervical vertebrae skeletal maturation, and between chronological age and frontal sinus width. Nonsignificant correlation was found between chronological age and antegonial notch depth. How to cite this article: Singh S, Sandhu N, Puri T, Gulati R, Kashyap R. A Study of Correlation of Various Growth Indicators with Chronological Age. Int J Clin Pediatr Dent 2015;8(3): 190-195.

A novel PFIB sample preparation protocol for correlative 3D X-ray CNT and FIB-TOF-SIMS tomography

Energy Technology Data Exchange (ETDEWEB)

Priebe, Agnieszka, E-mail: agnieszka.priebe@gmail.com [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Audoit, Guillaume; Barnes, Jean-Paul [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France)

2017-02-15

We present a novel sample preparation method that allows correlative 3D X-ray Computed Nano-Tomography (CNT) and Focused Ion Beam Time-Of-Flight Secondary Ion Mass Spectrometry (FIB-TOF-SIMS) tomography to be performed on the same sample. In addition, our invention ensures that samples stay unmodified structurally and chemically between the subsequent experiments. The main principle is based on modifying the topography of the X-ray CNT experimental setup before FIB-TOF-SIMS measurements by incorporating a square washer around the sample. This affects the distribution of extraction field lines and therefore influences the trajectories of secondary ions that are now guided more efficiently towards the detector. As the result, secondary ion detection is significantly improved and higher, i.e. statistically better, signals are obtained. - Highlights: • Novel sample preparation for correlative 3D X-ray CNT and FIB-TOF-SIMS is presented. • Two experiments are conducted on exactly the same sample without any modifications. • Introduction of a square washer around the sample leads to increased ion detection.

Correlates of trading sex for methamphetamine in a sample of HIV-negative heterosexual methamphetamine users.

Science.gov (United States)

Semple, Shirley J; Strathdee, Steffanie A; Zians, Jim; Patterson, Thomas L

2011-01-01

While many studies have examined correlates of trading sex for money, few have examined factors associated with exclusive trading of sex for drugs. We identified sociodemographic, behavioral, and psychological correlates of trading sex for methamphetamine in a sample of HIV-negative heterosexual men and women who were enrolled in a sexual risk reduction intervention in San Diego, California. Of 342 participants, 26% overall (21% of males and 31% of females) reported trading sex for methamphetamine in the past two months. Multiple logistic regression analysis revealed that recently trading sex for methamphetamine was independently associated with being female, homeless, binging on methamphetamine, sexual victimization in the past two months, engaging in anal sex 24 or more times in the past two months, and higher sexual compulsivity scores. Effective interventions for this high-risk population should consider gender-focused counseling for sexual abuse, motivational enhancement therapy, social-cognitive skills training, as well as enhanced access and utilization of social services, including drug treatment.

Time-dependent importance sampling in semiclassical initial value representation calculations for time correlation functions. II. A simplified implementation.

Science.gov (United States)

Tao, Guohua; Miller, William H

2012-09-28

An efficient time-dependent (TD) Monte Carlo (MC) importance sampling method has recently been developed [G. Tao and W. H. Miller, J. Chem. Phys. 135, 024104 (2011)] for the evaluation of time correlation functions using the semiclassical (SC) initial value representation (IVR) methodology. In this TD-SC-IVR method, the MC sampling uses information from both time-evolved phase points as well as their initial values, and only the "important" trajectories are sampled frequently. Even though the TD-SC-IVR was shown in some benchmark examples to be much more efficient than the traditional time-independent sampling method (which uses only initial conditions), the calculation of the SC prefactor-which is computationally expensive, especially for large systems-is still required for accepted trajectories. In the present work, we present an approximate implementation of the TD-SC-IVR method that is completely prefactor-free; it gives the time correlation function as a classical-like magnitude function multiplied by a phase function. Application of this approach to flux-flux correlation functions (which yield reaction rate constants) for the benchmark H + H(2) system shows very good agreement with exact quantum results. Limitations of the approximate approach are also discussed.

HIV-related risk behaviours and the correlates among rickshaw pullers of Kamrangirchar, Dhaka, Bangladesh: a cross-sectional study using probability sampling

Directory of Open Access Journals (Sweden)

Ravari Shahrzad

2009-03-01

Full Text Available Abstract Background National HIV serological and behavioural surveillance of Bangladesh repeatedly demonstrated a very high proportion of rickshaw pullers in Dhaka city, having sex with female sex workers (FSWs and using illicit substances. However, no study has been conducted to identify the correlates of having sex with FSWs among this population. This study aimed to describe behavioural profile of rickshaw pullers in Dhaka city using probability samples and to identify the correlates for having sex with FSWs in order to focus HIV prevention intervention. Methods Six hundred rickshaw pullers were randomly selected from rickshaw garages in the Kamrangirchar area, the single largest slum cluster of Dhaka, Bangladesh, during March–April 2008 using the Proportion Probability to Size method. Participants were interviewed, with a response rate of 99.2% (n = 595, using a structured questionnaire and asked about illicit substance use, sexual behaviour and risk perception for HIV and sexually transmitted diseases. Independent predictors of having sex with FSWs were analysed by multivariate analysis. A qualitative study was subsequently conducted with 30 rickshaw pullers to supplement the findings of the initial survey. Results The proportion of survey respondents who had sex with FSWs and those who used illicit substances in the previous 12 months period were 7.9% and 24.9%, respectively, much lower than the results achieved in the 2003–04 behavioural surveillance (72.8% and 89.9%, respectively. Multivariate analysis revealed the characteristics of younger age, being never married, living alone with family remaining in other districts and using illicit substances in the previous 12 months were significantly associated with having sex with FSWs. Conclusion HIV-related risk behaviour of our study population of the rickshaw pullers was lower than what has been suggested by the results of behavioural surveillance. While this discrepancy should be

Correlation of basic TL, OSL and IRSL properties of ten K-feldspar samples of various origins

Energy Technology Data Exchange (ETDEWEB)

Sfampa, I.K. [Aristotle University of Thessaloniki, Nuclear Physics Laboratory, 54124 Thessaloniki (Greece); Polymeris, G.S. [Institute of Nuclear Sciences, Ankara University, 06100 Besevler, Ankara (Turkey); Pagonis, V. [McDaniel College, Physics Department, Westminster, MD 21157 (United States); Theodosoglou, E. [Department of Mineralogy-Petrology-Economic Geology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Tsirliganis, N.C. [Laboratory of Radiation Applications and Archaeological Dating, Department of Archaeometry and Physicochemical Measurements, ‘Athena’ R.& I.C., Kimmeria University Campus, GR67100 Xanthi (Greece); Kitis, G., E-mail: gkitis@auth.gr [Aristotle University of Thessaloniki, Nuclear Physics Laboratory, 54124 Thessaloniki (Greece)

2015-09-15

Highlights: • OSL and IRSL bleaching behavior of ten K-feldspar samples is presented. • OSL and IRSL decay curves were component resolved using tunneling model. • The growth of integrated OSL and IRSL signals versus time was described by new expression based on tunneling model. • Correlation between TL, OSL and IRSL signals and of all properties with K-feldspar structure was discussed. - Abstract: Feldspars stand among the most widely used minerals in dosimetric methods of dating using thermoluminescence (TL), optically stimulated luminescence (OSL) and infrared stimulated luminescence (IRSL). Having very good dosimetric properties, they can in principle contribute to the dating of every site of archaeological and geological interest. The present work studies basic properties of ten naturally occurring K-feldspar samples belonging to three feldspar species, namely sanidine, orthoclase and microcline. The basic properties studied are (a) the influence of blue light and infrared stimulation on the thermoluminescence glow-curves, (b) the growth of OSL, IRSL, residual TL and TL-loss as a function of OSL and IRSL bleaching time and (c) the correlation between the OSL and IRSL signals and the energy levels responsible for the TL glow-curve. All experimental data were fitted using analytical expressions derived from a recently developed tunneling recombination model. The results show that the analytical expressions provide excellent fits to all experimental results, thus verifying the tunneling recombination mechanism in these materials and providing valuable information about the concentrations of luminescence centers.

[Study on correlation between ITS sequence of Arctium lappa and quality of Fructus Arctii].

Science.gov (United States)

Xu, Liang; Dou, Deqiang; Wang, Bing; Yang, Yanyun; Kang, Tingguo

2011-07-01

To study the correlation between ITS sequence of Arctium lappa and Fructus Arctii quality of different origin. The samples of Fructu arctii materials were collected from 26 different producing areas. Their ITS sequence were determined after polymerase chain reaction (PCR) and quality were evaluated through the determination of arctiin content by HPLC. Genetic diversity, genotype and correlation were analyzed by ClustalX (1.81), Mage 4.0, SPSS 13.0 statistical software. ITS sequence of A. was obtained from 26 samples, and was registered in the GenBank. Corresponding arctiin content of Fructus arctii and 1000-grain weight were determined. A. lappa genotype correlated with Fructus arctii quality by statistical analysis. The research provided a foundation for revealing the molecular mechanism of Fructus arctii geoherbs.

PyCCF: Python Cross Correlation Function for reverberation mapping studies

Science.gov (United States)

Sun, Mouyuan; Grier, C. J.; Peterson, B. M.

2018-05-01

PyCCF emulates a Fortran program written by B. Peterson for use with reverberation mapping. The code cross correlates two light curves that are unevenly sampled using linear interpolation and measures the peak and centroid of the cross-correlation function. In addition, it is possible to run Monto Carlo iterations using flux randomization and random subset selection (RSS) to produce cross-correlation centroid distributions to estimate the uncertainties in the cross correlation results.

Correlation between Cervical Vertebral Maturation Stages and Dental Maturation in a Saudi Sample

Directory of Open Access Journals (Sweden)

Nayef H Felemban

2017-01-01

Full Text Available Background: The aim of the present study was to compare the cervical vertebra maturation stages method and dental maturity using tooth calcification stages. Methods: The current study comprised of 405 subjects selected from orthodontic patients of Saudi origin coming to clinics of the specialized dental centers in western region of Saudi Arabia. Dental age was assessed according to the developmental stages of upper and lower third molars and skeletal maturation according to the cervical vertebrae maturation stage method. Statistical analysis was done using Kruskal-Wallis H, Mann-Whitney U test, Chi-Square test; t-test and Spearman correlation coefficient for inter group comparison. Results: The females were younger than males in all cervical stages. The CS1-CS2 show the period before the peak of growth, during CS3-CS5 it’s the pubertal growth spurt and CS6 is the period after the peak of the growth. The mean age and standard deviation for cervical stages of CS2, CS3 and CS4 were 12.09 ±1.72 years, 13.19 ±1.62 and 14.88 ±1.52 respectively. The Spearman correlation coefficients between cervical vertebrae and dental maturation were between 0.166 and 0.612, 0.243 and 0.832 for both sexes for upper and lower third molars. The significance levels for all coefficients were equal at 0.01 and 0.05. Conclusion: The results of this study showed that the skeletal maturity increased with the increase in dental ages for both genders. An early rate of skeletal maturation stage was observed in females. This study needs further analysis using a larger sample covering the entire dentition.

Prevalence and correlates of vaping cannabis in a sample of young adults.

Science.gov (United States)

Jones, Connor B; Hill, Melanie L; Pardini, Dustin A; Meier, Madeline H

2016-12-01

Vaping nicotine (i.e., the use of e-cigarettes and similar devices to inhale nicotine) is becoming increasingly popular among young people. Though some vaporizers are capable of vaporizing cannabis, sparse research has investigated this method of cannabis administration. The present study examines the prevalence and correlates of vaping cannabis in a sample of 482 college students. Participants reported high lifetime rates of vaping nicotine (37%) and cannabis (29%). Men (r s = 0.09, p = .047) and individuals from higher socioeconomic status families (r s = 0.14, p = .003) vaped cannabis more frequently than women and individuals from lower SES families. In addition, those who vaped cannabis more frequently were more open to new experiences (r s = 0.17, p vaping were frequent cannabis use (r s = 0.70, p vaping (r s = 0.46, p vaping cannabis, endorsed by 65% of those who had vaped cannabis, was convenience and discreetness for use in public places. Several correlates distinguished cannabis users who vaped from cannabis users who did not vape, most notably more frequent cannabis use (odds ratios [OR] = 3.68, p vaping (OR = 1.73, p vaping is prevalent among young adults, particularly among those who use other substances frequently and have more favorable attitudes toward smoking cannabis. Research is needed on the antecedents and potential harms and benefits of cannabis vaping in young adulthood. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Prevalence and correlates of body dysmorphic disorder in a community sample of adolescents.

Science.gov (United States)

Schneider, Sophie C; Turner, Cynthia M; Mond, Jonathan; Hudson, Jennifer L

2017-06-01

Body dysmorphic disorder typically begins in adolescence, yet little is known about the prevalence and correlates of the disorder in this age group. The current study aimed to explore the presenting features of adolescents meeting probable criteria for body dysmorphic disorder in a large community sample, and compare levels of comorbid psychopathology, quality of life and mental health service use between adolescents with probable body dysmorphic disorder and those without. Questionnaires were completed at school by 3149 adolescents: 63% male, aged 12-18 years ( M = 14.58). These assessed Diagnostic and Statistical Manual of Mental Disorders (4th ed.) body dysmorphic disorder criteria, past mental health service use and symptoms of body dysmorphic disorder, anxiety, depression, obsessive-compulsive disorder and eating disorders. In male participants, additional measures assessed quality of life, muscularity concerns, emotional symptoms, peer problems, conduct problems and hyperactivity. The prevalence of probable body dysmorphic disorder was 1.7%; there was no sex difference in prevalence, but older adolescents reported higher prevalence than younger adolescents. Probable body dysmorphic disorder participants reported substantially elevated levels of psychopathology, quality of life impairment and mental health service use compared to non-body dysmorphic disorder participants. The prevalence of body dysmorphic disorder in adolescents is similar to adult samples, and probable body dysmorphic disorder is associated with comorbidity, distress and functional impairment in a community sample. Further research is required to better understand the presentation of body dysmorphic disorder in adolescents, and to improve diagnosis and treatment.

Sampling Transition Pathways in Highly Correlated Complex Systems

Energy Technology Data Exchange (ETDEWEB)

Chandler, David

2004-10-20

This research grant supported my group's efforts to apply and extend the method of transition path sampling that we invented during the late 1990s. This methodology is based upon a statistical mechanics of trajectory space. Traditional statistical mechanics focuses on state space, and with it, one can use Monte Carlo methods to facilitate importance sampling of states. With our formulation of a statistical mechanics of trajectory space, we have succeeded at creating algorithms by which importance sampling can be done for dynamical processes. In particular, we are able to study rare but important events without prior knowledge of transition states or mechanisms. In perhaps the most impressive application of transition path sampling, my group combined forces with Michele Parrinello and his coworkers to unravel the dynamics of auto ionization of water [5]. This dynamics is the fundamental kinetic step of pH. Other applications concern nature of dynamics far from equilibrium [1, 7], nucleation processes [2], cluster isomerization, melting and dissociation [3, 6], and molecular motors [10]. Research groups throughout the world are adopting transition path sampling. In part this has been the result of our efforts to provide pedagogical presentations of the technique [4, 8, 9], as well as providing new procedures for interpreting trajectories of complex systems [11].

Correlates of professional burnout in a sample of employees of cell and tissue banks in Poland.

Science.gov (United States)

Kamiński, Artur; Rozenek, Hanna; Banasiewicz, Jolanta; Wójtowicz, Stanisław; Błoński, Artur; Owczarek, Krzysztof

2018-02-03

Job Demands-Resources model proposes that the development of burnout follows excessive job demands and lack of job resources. Job demands are predictive of feeling of exhaustion, and lack of job resources-disengagement from work. This pilot study investigated professional burnout and its correlates in employees of Polish cell and tissue banks, many of whom were involved in procurement and processing of tissues from deceased donors, as it was hypothesized that job burnout in this population might influence the effectiveness of cell and tissue transplantation network in our country. This study utilized the Polish version of the Oldenburg Burnout Inventory (OLBI), which measures the two dimensions of burnout (exhaustion and disengagement), and the Psychosocial Working Conditions Questionnaire (PWC), a Polish instrument used for monitoring psychosocial stress at work. The study sample consisted of 31 participants. Their average time of working in a cell and tissue bank was 13.20 years. Majority of the PWC scales and subscales scores fell in the Average range, and the OLBI results for the Disengagement and the Exhaustion scales were in the Average range. A number of correlations between the Exhaustion or Disengagement and the PWC scales and subscales were detected, majority of which fell in the Moderate range. In spite of the limited number of participants, the results of this pilot study are consistent with the burnout literature reports. Among the detected correlates of professional burnout, it is job-related support which seems to be the most important factor which may influence the efficacy of transplantation network in Poland.

Some remarks on estimating a covariance structure model from a sample correlation matrix

OpenAIRE

Maydeu Olivares, Alberto; Hernández Estrada, Adolfo

2000-01-01

A popular model in structural equation modeling involves a multivariate normal density with a structured covariance matrix that has been categorized according to a set of thresholds. In this setup one may estimate the covariance structure parameters from the sample tetrachoricl polychoric correlations but only if the covariance structure is scale invariant. Doing so when the covariance structure is not scale invariant results in estimating a more restricted covariance structure than the one i...

Correlation of Cadmium and Magnesium in the Blood and Serum Samples of Smokers and Non-Smokers Chronic Leukemia Patients.

Science.gov (United States)

Khan, Noman; Afridi, Hasan Imran; Kazi, Tasneem Gul; Arain, Muhammad Balal; Bilal, Muhammad; Akhtar, Asma; Khan, Mustafa

2017-03-01

It was studied that cancer-causing processes are related with the disproportions of essential and toxic elements in body tissues and fluid. The purpose of the current study was to evaluate the levels of magnesium (Mg) and cadmium (Cd) in serum and blood samples of smokers and nonsmokers who have chronic myeloid (CML) and lymphocytic (CLL) leukemia, age ranged 31-50 years. For comparative study, age-matched smokers and nonsmoker males were chosen as controls/referents. The levels of elements in patient were analyzed before any treatment by atomic absorption spectrophotometer, after microwave assisted acid digestion. The validation of the method was done by using certified reference materials of serum and blood samples. The resulted data indicated that the adult male smokers and nonsmokers have two- to fourfold higher levels of Cd in the blood and sera samples as compared to the referents (p blood and serum samples of both types of leukemia patients as related to referent values. The resulted data indicates significant negative correlation among Mg and Cd in leukemia patients and smoker referents. Further studies are needed to clarify the role of these elements in pathogenesis of chronic leukemia.

Microanalysis study of archaeological mural samples containing Maya blue pigment

International Nuclear Information System (INIS)

Sanchez del Rio, M.; Martinetto, P.; Somogyi, A.; Reyes-Valerio, C.; Dooryhee, E.; Peltier, N.; Alianelli, L.; Moignard, B.; Pichon, L.; Calligaro, T.; Dran, J.-C.

2004-01-01

Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used

Microanalysis study of archaeological mural samples containing Maya blue pigment

Science.gov (United States)

Sánchez del Río, M.; Martinetto, P.; Somogyi, A.; Reyes-Valerio, C.; Dooryhée, E.; Peltier, N.; Alianelli, L.; Moignard, B.; Pichon, L.; Calligaro, T.; Dran, J.-C.

2004-10-01

Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used.

Microanalysis study of archaeological mural samples containing Maya blue pigment

Energy Technology Data Exchange (ETDEWEB)

Sanchez del Rio, M. [ESRF, BP220, F-38043 Grenoble (France)]. E-mail: srio@esrf.fr; Martinetto, P. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Somogyi, A. [ESRF, BP220, F-38043 Grenoble (France); Reyes-Valerio, C. [INAH, Mexico DF (Mexico); Dooryhee, E. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Peltier, N. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Alianelli, L. [INFM-OGG c/o ESRF, BP220, F-38043 Grenoble Cedex (France); Moignard, B. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Pichon, L. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Calligaro, T. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Dran, J.-C. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France)

2004-10-08

Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used.

Study of Bose-Einstein Correlations in $e^{+}e^{-}\\to W^{+}W^{-}$ events at LEP

CERN Document Server

Abbiendi, G.; Akesson, P.F.; Alexander, G.; Allison, John; Amaral, P.; Anagnostou, G.; Anderson, K.J.; Asai, S.; Axen, D.; Azuelos, G.; Bailey, I.; Barberio, E.; Barillari, T.; Barlow, R.J.; Batley, R.J.; Bechtle, P.; Behnke, T.; Bell, Kenneth Watson; Bell, P.J.; Bella, G.; Bellerive, A.; Benelli, G.; Bethke, S.; Biebel, O.; Boeriu, O.; Bock, P.; Boutemeur, M.; Braibant, S.; Brigliadori, L.; Brown, Robert M.; Buesser, K.; Burckhart, H.J.; Campana, S.; Carnegie, R.K.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, D.G.; Ciocca, C.; Csilling, A.; Cuffiani, M.; Dado, S.; De Roeck, A.; De Wolf, E.A.; Desch, K.; Dienes, B.; Donkers, M.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Etzion, E.; Fabbri, F.; Feld, L.; Ferrari, P.; Fiedler, F.; Fleck, I.; Ford, M.; Frey, A.; Gagnon, P.; Gary, John William; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Giunta, Marina; Goldberg, J.; Gross, E.; Grunhaus, J.; Gruwe, M.; Gunther, P.O.; Gupta, A.; Hajdu, C.; Hamann, M.; Hanson, G.G.; Harel, A.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Herten, G.; Heuer, R.D.; Hill, J.C.; Hoffman, Kara Dion; Horvath, D.; Igo-Kemenes, P.; Ishii, K.; Jeremie, H.; Jovanovic, P.; Junk, T.R.; Kanaya, N.; Kanzaki, J.; Karlen, D.; Kawagoe, K.; Kawamoto, T.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kluth, S.; Klein, K.; Kobayashi, T.; Kobel, M.; Komamiya, S.; Kramer, T.; Kress, T.; Krieger, P.; von Krogh, J.; Kruger, K.; Kuhl, T.; Kupper, M.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Layter, J.G.; Lellouch, D.; Lettso, J.; Levinson, L.; Lillich, J.; Lloyd, S.L.; Loebinger, F.K.; Lu, J.; Ludwig, A.; Ludwig, J.; Mader, W.; Marcellini, S.; Martin, A.J.; Masetti, G.; Mashimo, T.; Mattig, Peter; McKenna, J.; McPherson, R.A.; Meijers, F.; Menges, W.; Merritt, F.S.; Mes, H.; Meyer, Niels T.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Moed, S.; Mohr, W.; Mori, T.; Mutter, A.; Nagai, K.; Nakamura, I.; Nanjo, H.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oh, A.; Oreglia, M.J.; Orito, S.; Pahl, C.; Pasztor, G.; Pater, J.R.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poli, B.; Pooth, O.; Przybycien, M.; Quadt, A.; Rabbertz, K.; Rembser, C.; Renkel, P.; Roney, J.M.; Rozen, Y.; Runge, K.; Sachs, K.; Saeki, T.; Sarkisyan, E.K.G.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schieck, J.; Schoerner-Sadenius, Thomas; Schroder, Matthias; Schumacher, M.; Scott, W.G.; Seuster, R.; Shears, T.G.; Shen, B.C.; Sherwood, P.; Skuja, A.; Smith, A.M.; Sobie, R.; Soldner-Rembold, S.; Spano, F.; Stahl, A.; Strom, David M.; Strohmer, R.; Tarem, S.; Tasevsky, M.; Teuscher, R.; Thomson, M.A.; Torrence, E.; Toya, D.; Tran, P.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turner-Watson, M.F.; Ueda, I.; Ujvari, B.; Vollmer, C.F.; Vannerem, P.; Vertesi, R.; Verzocchi, M.; Voss, H.; Vossebeld, J.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wengler, T.; Wermes, N.; Wilson, G.W.; Wilson, J.A.; Wolf, G.; Wyatt, T.R.; Yamashita, S.; Zer-Zion, D.; Zivkovic, Lidija

2004-01-01

Bose-Einstein correlation between like-sign charged-particle pairs in e+e- -> W+W- events recorded with the OPAL detector at LEP at centre-of-mass energies between 183 GeV and 209 GeV are studied. Recently proposed methods which allow direct searches for correlations in the data via distributions of test variables are used to investigate the presence of correlations between hadrons originating from different W bosons in W+W- -> qqqq events. Within the statistics of the data sample no evidence for inter-WW Bose-Einstein correlations is obtained. The data are also compared with predictions of a recent implementation of Bose-Einstein correlation effects in the Monte Carlo model PYTHIA.

Quantification of Hg excretion and distribution in biological samples of mercury-dental-amalgam users and its correlation with biological variables.

Science.gov (United States)

Gul, Nayab; Khan, Sardar; Khan, Abbas; Nawab, Javed; Shamshad, Isha; Yu, Xinwei

2016-10-01

This is the first study conducted to quantify the excretion and distribution of mercury (Hg) with time (days) in the biological samples collected from Hg dental amalgam users (MDA). The individuals, with Hg-based dental filling were selected, and their biological samples (red blood cells (RBCs), plasma, urine, hair, and nails) were collected on first, third, and 12th day of fillings. The concentrations of Hg observed in the biological samples of MDA were also correlated with the biological variables such as age, weight, restoration, fish consumption, number, and surface area of fillings. The concentrations of Hg in the biological samples of MDA were found 6-8 times higher than the non-amalgam users (control). The concentrations of Hg in the RBCs (4.39 μg/L), plasma (3.02 μg/L), and urine (22.5 μg/L) on first day of filling were found comparatively higher than the concentrations observed on third day (2.15, 1.46, and 12.3 μg/L for RBCs, plasma, urine, respectively) and 12th day (3.05, 2.5, 9.12 μg/L for RBCs, plasma, urine, respectively), while Hg concentrations were found lower in the hair and nails on third day of fillings (1.53 μg/g for hair and 2.35 μg/g for nails) as compared to the 12th day (2.95 μg/g for hair and 3.5 μg/g for nails). The correlations were found significant (p ˂ 0.05) between Hg concentrations in the biological samples of MDA and biological variables (the number of restoration, fish consumption, number, and surface area of fillings), while no significant (p ˃ 0.05) correlations were observed for Hg concentrations in the biological samples with age and weight of MDA. These observations unveil the fact that the use of Hg-based dental filling is the undesirable exposure to Hg which should be replaced by composite (a safer filling material).

A Study of the Radio Continuum Far Infrared Correlation at Small Scales in the Galaxy

Science.gov (United States)

Rodriguez-Martinez, Monica I.; Allen, R. J.; Wiklind, T.; Loinard, L.

2006-12-01

We present a study of the behavior of the Radio Continuum (RC) Far Infrared (FIR) correlation on scales corresponding to the size of small molecular clouds. This was done by comparing the spatial distribution of RC emission and FIR emission from a sample of several regions, distributed within the range 79∘ ≤ l ≤ 174∘ in the Galaxy. We have examined the 408 and 1420 MHz mosaic images of the sample, from the Canadian Galactic Plane Survey (CGPS), which later were compared with images at 60 and 100 μm. Preliminary results suggest that the RC -FIR correlation still holds at small scales, since a good qualitative correlation between RC and FIR emission is found. The physical process involved that may cause such correlation will be discussed as well as the nature of the RC emission. This research makes use of data from the Canadian Galactic Plane Survey.

Characteristics of angular cross correlations studied by light scattering from two-dimensional microsphere films

Science.gov (United States)

Schroer, M. A.; Gutt, C.; Grübel, G.

2014-07-01

Recently the analysis of scattering patterns by angular cross-correlation analysis (CCA) was introduced to reveal the orientational order in disordered samples with special focus to future applications on x-ray free-electron laser facilities. We apply this CCA approach to ultra-small-angle light-scattering data obtained from two-dimensional monolayers of microspheres. The films were studied in addition by optical microscopy. This combined approach allows to calculate the cross-correlations of the scattering patterns, characterized by the orientational correlation function Ψl(q), as well as to obtain the real-space structure of the monolayers. We show that CCA is sensitive to the orientational order of monolayers formed by the microspheres which are not directly visible from the scattering patterns. By mixing microspheres of different radii the sizes of ordered monolayer domains is reduced. For these samples it is shown that Ψl(q) quantitatively describes the degree of hexagonal order of the two-dimensional films. The experimental CCA results are compared with calculations based on the microscopy images. Both techniques show qualitatively similar features. Differences can be attributed to the wave-front distortion of the laser beam in the experiment. This effect is discussed by investigating the effect of different wave fronts on the cross-correlation analysis results. The so-determined characteristics of the cross-correlation analysis will be also relevant for future x-ray-based studies.

Stability of BDNF in Human Samples Stored Up to 6 Months and Correlations of Serum and EDTA-Plasma Concentrations.

Science.gov (United States)

Polyakova, Maryna; Schlögl, Haiko; Sacher, Julia; Schmidt-Kassow, Maren; Kaiser, Jochen; Stumvoll, Michael; Kratzsch, Jürgen; Schroeter, Matthias L

2017-06-03

Brain-derived neurotrophic factor (BDNF), an important neural growth factor, has gained growing interest in neuroscience, but many influencing physiological and analytical aspects still remain unclear. In this study we assessed the impact of storage time at room temperature, repeated freeze/thaw cycles, and storage at -80 °C up to 6 months on serum and ethylenediaminetetraacetic acid (EDTA)-plasma BDNF. Furthermore, we assessed correlations of serum and plasma BDNF concentrations in two independent sets of samples. Coefficients of variations (CVs) for serum BDNF concentrations were significantly lower than CVs of plasma concentrations ( n = 245, p = 0.006). Mean serum and plasma concentrations at all analyzed time points remained within the acceptable change limit of the inter-assay precision as declared by the manufacturer. Serum and plasma BDNF concentrations correlated positively in both sets of samples and at all analyzed time points of the stability assessment ( r = 0.455 to r s = 0.596; p plasma up to 6 months. Due to a higher reliability, we suggest favoring serum over EDTA-plasma for future experiments assessing peripheral BDNF concentrations.

Perceived financial retirement preparedness and its correlates: a national study in Israel.

Science.gov (United States)

Segel-Karpas, Dikla; Werner, Perla

2014-01-01

Studies suggest that a large proportion of adults do not manage to save enough for retirement. Correlates of retirement saving behaviors have yet to be fully understood. The goal of this study was to examine perceived financial preparedness for retirement and its correlates. We studied the effect of perceived financial knowledge and involvement, social and institutional support, and attitudes toward retirement in a national sample of 227 non-retired Israeli adults (mean age = 44; 53% female; 81% Jewish). Results indicated that only about 20% perceived themselves as financially prepared for retirement. The main correlates of financial preparedness were financial knowledge and involvement in financial activities. The results show that a large proportion of the Israeli population feel underprepared for retirement. Those who perceive themselves as having high levels of financial knowledge are less predisposed to feel underprepared. Future research should examine the relationship between perceived financial preparedness and actual savings. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

The correlations between natural elements (K, U, Th) concentrations and thermal neutron absorption cross-section value (Σa) for rock samples of Carpatia area

International Nuclear Information System (INIS)

Swakon, J.; Cywicka-Jakiel, T.; Drozdowicz, E.; Gabanska, B.; Loskiewicz, J.; Woznicka, U.

1991-01-01

The paper presents a study of correlations between concentrations of potassium, uranium and thorium and thermal neutron absorption cross section in rock samples. This knowledge of correlation should help in recognizing the expansion ways and accumulation places of the elements responsible of high thermal neutron absorption cross section in some geological environments. The correlations show the existence of connections between the thermal neutron absorption cross section value and natural radioactivity elements concentration in rocks. The results confirm the existence of correlations between natural radioactive elements concentrations (particularly thorium) and thermal neutron absorption cross - section value in some rocks. (author). 12 refs, 23 figs, 6 tabs

Quantification of the neurotoxic beta-carboline harmane in barbecued/grilled meat samples and correlation with level of doneness.

Science.gov (United States)

Louis, Elan D; Zheng, Wei; Jiang, Wendy; Bogen, Kenneth T; Keating, Garrett A

2007-06-01

Harmane, one of the heterocyclic amines (HCAs), is a potent neurotoxin linked to human diseases. Dietary exposure, especially in cooked meats, is the major source of exogenous exposure for humans. However, knowledge of harmane concentrations in cooked meat samples is limited. Our goals were to (1) quantify the concentration of harmane in different types of cooked meat samples, (2) compare its concentration to that of other more well-understood HCAs, and (3) examine the relationship between harmane concentration and level of doneness. Thirty barbecued/grilled meat samples (8 beef steak, 12 hamburger, 10 chicken) were analyzed for harmane and four other HCAs (2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine [PhIP], amino-3,8-dimethylimidazo[4,5-f]quinoxaline [MeIQx], 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline [DiMeIQx], and 2-amino-1,6-dimethylfuro[3,2-e]imidazo[4,5-b]pyridine [IFP]). Mean (+/- SD) harmane concentration was 5.63 (+/- 6.63) ng/g; harmane concentration was highest in chicken (8.48 +/- 9.86 ng/g) and lowest in beef steak (3.80 +/- 3.6 ng/g). Harmane concentration was higher than that of the other HCAs and significantly correlated with PhIP concentration. Harmane concentration was associated with meat doneness in samples of cooked beef steak and hamburger, although the correlation between meat doneness and concentration was greater for PhIP than for harmane. Evidence indicates that harmane was detectable in nanograms per gram quantities in cooked meat (especially chicken) and, moreover, was more abundant than other HCAs. There was some correlation between meat doneness and harmane concentration, although this correlation was less robust than that observed for PhIP. Data such as these may be used to improve estimation of human dietary exposure to this neurotoxin.

Quantification of the Neurotoxic β-Carboline Harmane in Barbecued/Grilled Meat Samples and Correlation with Level of Doneness

Science.gov (United States)

Louis, Elan D.; Zheng, Wei; Jiang, Wendy; Bogen, Kenneth T.; Keating, Garrett A.

2016-01-01

Harmane, one of the heterocyclic amines (HCAs), is a potent neurotoxin linked to human diseases. Dietary exposure, especially in cooked meats, is the major source of exogenous exposure for humans. However, knowledge of harmane concentrations in cooked meat samples is limited. Our goals were to (1) quantify the concentration of harmane in different types of cooked meat samples, (2) compare its concentration to that of other more well-understood HCAs, and (3) examine the relationship between harmane concentration and level of doneness. Thirty barbecued/grilled meat samples (8 beef steak, 12 hamburger, 10 chicken) were analyzed for harmane and four other HCAs (2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine [PhIP], amino-3,8-dimethylimidazo[4,5-f]quinoxaline [MeIQx], 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline [DiMeIQx], and 2-amino-1,6-dimethylfuro[3,2-e]imidazo[4,5-b]pyridine [IFP]). Mean (± SD) harmane concentration was 5.63 (± 6.63) ng/g; harmane concentration was highest in chicken (8.48 ± 9.86 ng/g) and lowest in beef steak (3.80 ± 3.6 ng/g). Harmane concentration was higher than that of the other HCAs and significantly correlated with PhIP concentration. Harmane concentration was associated with meat doneness in samples of cooked beef steak and hamburger, although the correlation between meat doneness and concentration was greater for PhIP than for harmane. Evidence indicates that harmane was detectable in nanograms per gram quantities in cooked meat (especially chicken) and, moreover, was more abundant than other HCAs. There was some correlation between meat doneness and harmane concentration, although this correlation was less robust than that observed for PhIP. Data such as these may be used to improve estimation of human dietary exposure to this neurotoxin. PMID:17497412

Closed-Form Representations of the Density Function and Integer Moments of the Sample Correlation Coefficient

Directory of Open Access Journals (Sweden)

Serge B. Provost

2015-07-01

Full Text Available This paper provides a simplified representation of the exact density function of R, the sample correlation coefficient. The odd and even moments of R are also obtained in closed forms. Being expressed in terms of generalized hypergeometric functions, the resulting representations are readily computable. Some numerical examples corroborate the validity of the results derived herein.

Study of Bose-Einstein correlations in e+e-→W+W- events at LEP

International Nuclear Information System (INIS)

Abbiendi, G.; Aimsley, C.; Aakesson, C.

2004-01-01

Bose-Einstein correlations between like-sign charged-particle pairs in e + e - →W + W - events recorded with the OPAL detector at LEP at centre-of-mass energies between 183 GeV and 209 GeV are studied. Recently proposed methods which allow direct searches for correlations in the data via distributions of test variables are used to investigate the presence of correlations between hadrons originating from different W bosons in W + W - →q anti qq anti q events. Within the statistics of the data sample no evidence for inter-WW Bose-Einstein correlations is obtained. The data are also compared with predictions of a recent implementation of Bose-Einstein correlation effects in the Monte Carlo model PYTHIA. (orig.)

SDSS-II SUPERNOVA SURVEY: AN ANALYSIS OF THE LARGEST SAMPLE OF TYPE IA SUPERNOVAE AND CORRELATIONS WITH HOST-GALAXY SPECTRAL PROPERTIES

International Nuclear Information System (INIS)

Wolf, Rachel C.; Gupta, Ravi R.; Sako, Masao; Fischer, John A.; March, Marisa C.; Fischer, Johanna-Laina; D’Andrea, Chris B.; Smith, Mathew; Kessler, Rick; Scolnic, Daniel M.; Jha, Saurabh W.; Campbell, Heather; Nichol, Robert C.; Olmstead, Matthew D.; Richmond, Michael; Schneider, Donald P.

2016-01-01

Using the largest single-survey sample of Type Ia supernovae (SNe Ia) to date, we study the relationship between properties of SNe Ia and those of their host galaxies, focusing primarily on correlations with Hubble residuals (HRs). Our sample consists of 345 photometrically classified or spectroscopically confirmed SNe Ia discovered as part of the SDSS-II Supernova Survey (SDSS-SNS). This analysis utilizes host-galaxy spectroscopy obtained during the SDSS-I/II spectroscopic survey and from an ancillary program on the SDSS-III Baryon Oscillation Spectroscopic Survey that obtained spectra for nearly all host galaxies of SDSS-II SN candidates. In addition, we use photometric host-galaxy properties from the SDSS-SNS data release such as host stellar mass and star formation rate. We confirm the well-known relation between HR and host-galaxy mass and find a 3.6 σ significance of a nonzero linear slope. We also recover correlations between HR and host-galaxy gas-phase metallicity and specific star formation rate as they are reported in the literature. With our large data set, we examine correlations between HR and multiple host-galaxy properties simultaneously and find no evidence of a significant correlation. We also independently analyze our spectroscopically confirmed and photometrically classified SNe Ia and comment on the significance of similar combined data sets for future surveys.

Robust canonical correlations: A comparative study

OpenAIRE

Branco, JA; Croux, Christophe; Filzmoser, P; Oliveira, MR

2005-01-01

Several approaches for robust canonical correlation analysis will be presented and discussed. A first method is based on the definition of canonical correlation analysis as looking for linear combinations of two sets of variables having maximal (robust) correlation. A second method is based on alternating robust regressions. These methods axe discussed in detail and compared with the more traditional approach to robust canonical correlation via covariance matrix estimates. A simulation study ...

Column-Parallel Single Slope ADC with Digital Correlated Multiple Sampling for Low Noise CMOS Image Sensors

NARCIS (Netherlands)

Chen, Y.; Theuwissen, A.J.P.; Chae, Y.

2011-01-01

This paper presents a low noise CMOS image sensor (CIS) using 10/12 bit configurable column-parallel single slope ADCs (SS-ADCs) and digital correlated multiple sampling (CMS). The sensor used is a conventional 4T active pixel with a pinned-photodiode as photon detector. The test sensor was

Study of correlation between viral and bacterial contamination of waste water

International Nuclear Information System (INIS)

Khoffi, Nessrine

2013-01-01

Our study was developped following two main axes: the detection of fecal indicators (Escherichia coli) and the investigation of enteroviruses indicators of viral contamination in 3 Tunisian WWTP residues. The detection of enetroviruses was performed by real time PCR. Enteroviruses were detected in all samples whiles, 26 pour cent strongly positive, 53 pour cent moderately positive and 21 pour cent weakly positive. In addition, all samples were contaminated by E.coli with a decrease of concentration in effluent compared to influent. The results showed that E. coli is sensitive to biological treatment in charguia. A correlation between viral and bacterial contamination may be considered.

Photometric study of divine proportion and its correlation with facial attractiveness

Directory of Open Access Journals (Sweden)

Ana Paula Lazzari Marques Peron

2012-04-01

Full Text Available OBJECTIVE: The aim of this study was to evaluate if there is correlation between perception of facial esthetic and divine proportion, verifying if most attractive faces are closer to and less attractive faces are more distant to this proportion. METHODS: Standard facial photographs (frontal and lateral in natural head position were taken of a sample of 85 Brazilian Caucasian women, with mean age of 23 years and 9 months. The photographs were evaluated by 5 orthodontists, 5 artists and 5 laymen and were classified, according to their subjective analysis of facial esthetic, in pleasant, acceptable and not pleasant. Frontal photographs were evaluated by divine proportion analysis using the computerized method. RESULTS AND CONCLUSIONS: According to subjective analysis the sample consisted 18.8% of pleasant, 70.6% of acceptable and 10.6% of not pleasant faces. After statistical analysis, a lack of agreement was verified in esthetic facial preferences among the three groups of observers. It was also possible to verify that in this research there was no correlation between perception of facial beauty and divine proportion.

High energy x-ray scattering studies of strongly correlated oxides

International Nuclear Information System (INIS)

Hatton, Peter D; Wilkins, S B; Spencer, P D; Zimmermann, M v; D'Almeida, T

2003-01-01

Many transition metal oxides display strongly correlated charge, spin, or orbital ordering resulting in varied phenomena such as colossal magnetoresistance, high temperature superconductivity, metal-insulator transitions etc. X-ray scattering is one of the principle techniques for probing the structural response to such effects. In this paper, we discuss and review the use of synchrotron radiation high energy x-rays (50-200 keV) for the study of transition metal oxides such as nickelates (La 2-x Sr x NiO 4 ) and manganites (La 2-2x Sr 1+2x Mn 2 O 7 ). High energy x-rays have sufficient penetration to allow us to study large flux-grown single crystals. The huge increase in sample scattering volume means that extremely weak peaks can be observed. This allows us to study very weak charge ordering. Measurements of the intensity, width and position of the charge ordering satellites as a function of temperature provide us with quantitative measures of the charge amplitude, inverse correlation length and wavevector of the charge ordering

Transport studies in p-type double quantum well samples

International Nuclear Information System (INIS)

Hyndman, R.J.

2000-01-01

The motivation for the study of double quantum well samples is that the extra spatial degree of freedom can modify the ground state energies of the system, leading to new and interesting many body effects. Electron bi-layers have been widely studied but the work presented here is the first systematic study of transport properties of a p-type, double quantum well system. The samples, grown on the 311 plane, consisted of two 100A GaAs wells separated by a 30A AlAs barrier. The thin barrier in our structures, gives rise to very strong inter-layer Coulombic interactions but in contrast to electron double quantum well samples, tunnelling between the two wells is very weak. This is due to the large effective mass of holes compared with electrons. It is possible to accurately control the total density of a sample and the relative occupancy of each well using front and back gates. A systematic study of the magnetoresistance properties of the p-type bi-layers, was carried out at low temperatures and in high magnetic fields, for samples covering a range of densities. Considerable care was required to obtain reliable results as the samples were extremely susceptible to electrical shock and were prone to drift in density slowly over time. With balanced wells, the very low tunnelling in the p-type bi-layer leads to a complete absence of all odd integers in both resistance and thermopower except for the v=1 state, ( v 1/2 in each layer) where v is the total Landau level filling factor. Unlike other FQHE features the v=1 state strengthens with increased density as inter-layer interactions increase in strength over intra-layer interactions. The state is also destroyed at a critical temperature, which is much lower than the measured activation temperature. This is taken as evidence for a finite temperature phase transition predicted for the bi-layer v=1. From the experimental observations, we construct a phase diagram for the state, which agree closely with theoretical predictions

The moderating effects of sample type as evidence of the effects of faking on personality scale correlations and factor structure

Directory of Open Access Journals (Sweden)

KEVIN M. BRADLEY

2006-09-01

Full Text Available Motivational differences as a function of sample type (applicants versus incumbents have frequently been suspected of causing meaningful differences in the psychometric properties of personality inventories due to the effects of faking. In this quantitative review, correlations among the Big Five personality constructs were estimated and sample type was examined as a potential moderator of the personality construct inter-correlations. The resulting subgroup meta-analytic correlation matrices were factor-analyzed, and the second order factor solutions for job incumbents and job applicants were compared. Results of the meta-analyses indicate frequent, but small moderating effects. The second order factor analyses indicated that the observed moderation had little effect on the congruence of factor loadings. Together, the results are consistent with the position that faking is of little practical consequence in selection settings.

Prevalence and correlates of beta human papillomavirus detection in fingernail samples from mid-adult women

Directory of Open Access Journals (Sweden)

Rachel L. Winer

2018-06-01

Full Text Available Cutaneous human papillomaviruses (HPVs have not been evaluated in fingernails from healthy individuals. To determine prevalence and correlates of β-HPVs in fingernails from healthy mid-adult women, we tested archived samples collected from 2011 to 2012 using a multiplex PCR combined with Luminex technology for 46 β-HPV genotypes. One hundred thirteen (61.1% of 185 fingernail samples were positive for β-HPV, and the median number of types detected in positive samples was 2 (interquartile range: 1–4. The most common genotypes detected were HPV-23 (β−2 (13.5%, HPV-38 (β−2 (13.0%, HPV-5 (β−1 (9.2%, HPV-107 (β−2 (8.7%, and HPV-120 (β−2 (8.7%. In multivariate analysis, β-HPV detection was associated with age (prevalence ratio [PR] for women 40–51 years versus 30–39 years = 1.30, 95% CI: 1.05–1.62 and race (PR for non-white versus white race = 0.65, 95% CI: 0.45–0.94. The prevalence of β-HPV in fingernail samples from healthy mid-adult women was similar to the prevalence of β-HPV reported at other cutaneous sites in prior studies. We did not identify any significant health or sexual behavior predictors of β-HPV detection in fingernails. Our results support the hypothesis that fingers may serve as a source of transmission or autoinoculation of cutaneous HPVs to other anatomic sites. Keywords: Fingernails, Women, Beta-HPV, Prevalence, Mid-adult, Risk factor

A study on Improvisation in a Musical performance using Multifractal Detrended Cross Correlation Analysis

Science.gov (United States)

Sanyal, Shankha; Banerjee, Archi; Patranabis, Anirban; Banerjee, Kaushik; Sengupta, Ranjan; Ghosh, Dipak

2016-11-01

MFDFA (the most rigorous technique to assess multifractality) was performed on four Hindustani music samples played on same 'raga' sung by the same performer. Each music sample was divided into six parts and 'multifractal spectral width' was determined for each part corresponding to the four samples. The results obtained reveal that different parts of all the four sound signals possess spectral width of widely varying values. This gives a cue of the so called 'musical improvisation' in all music samples, keeping in mind they belong to the bandish part of the same raga. Formal compositions in Hindustani raga are juxtaposed with the improvised portions, where an artist manoeuvers his/her own creativity to bring out a mood that is specific for that particular performance, which is known as 'improvisation'. Further, this observation hints at the association of different emotions even in the same bandish of the same raga performed by the same artist, this interesting observation cannot be revealed unless rigorous non-linear technique explores the nature of musical structure. In the second part, we applied MFDXA technique to explore more in-depth about 'improvisation' and association with emotion. This technique is applied to find the degree of cross-correlation (γx) between the different parts of the samples. Pronounced correlation has been observed in the middle parts of the all the four samples evident from higher values of γx ​whereas the other parts show weak correlation. This gets further support from the values of spectral width from different parts of the sample - width of those parts is significantly different from other parts. This observation is extremely new both in respect of musical structure of so called improvisation and associated emotion. The importance of this study in application area of cognitive music therapy is immense.

Automated modal parameter estimation using correlation analysis and bootstrap sampling

Science.gov (United States)

Yaghoubi, Vahid; Vakilzadeh, Majid K.; Abrahamsson, Thomas J. S.

2018-02-01

The estimation of modal parameters from a set of noisy measured data is a highly judgmental task, with user expertise playing a significant role in distinguishing between estimated physical and noise modes of a test-piece. Various methods have been developed to automate this procedure. The common approach is to identify models with different orders and cluster similar modes together. However, most proposed methods based on this approach suffer from high-dimensional optimization problems in either the estimation or clustering step. To overcome this problem, this study presents an algorithm for autonomous modal parameter estimation in which the only required optimization is performed in a three-dimensional space. To this end, a subspace-based identification method is employed for the estimation and a non-iterative correlation-based method is used for the clustering. This clustering is at the heart of the paper. The keys to success are correlation metrics that are able to treat the problems of spatial eigenvector aliasing and nonunique eigenvectors of coalescent modes simultaneously. The algorithm commences by the identification of an excessively high-order model from frequency response function test data. The high number of modes of this model provides bases for two subspaces: one for likely physical modes of the tested system and one for its complement dubbed the subspace of noise modes. By employing the bootstrap resampling technique, several subsets are generated from the same basic dataset and for each of them a model is identified to form a set of models. Then, by correlation analysis with the two aforementioned subspaces, highly correlated modes of these models which appear repeatedly are clustered together and the noise modes are collected in a so-called Trashbox cluster. Stray noise modes attracted to the mode clusters are trimmed away in a second step by correlation analysis. The final step of the algorithm is a fuzzy c-means clustering procedure applied to

A Study of Correlation of Various Growth Indicators with Chronological Age

OpenAIRE

Singh, Sarabjeet; Sandhu, Navreet; Puri, Taruna; Gulati, Ritika; Kashyap, Rita

2015-01-01

ABSTRACT Introduction: The aim of this study was to assess the relationship of chronological age with cervical vertebrae skeletal maturation, frontal sinus width and antegonial notch depth and a correlation, if any, among the three variables. Materials and methods: The samples were derived from lateral cephalometric radiographs of 80 subjects (40 males, 40 females; age range: 10 to 19 years). Cervical vertebral development was evaluated by the method of Hassel and Farman, frontal sinus width ...

Correlation studies between serum concentrations of zinc and lipoproteins

Energy Technology Data Exchange (ETDEWEB)

Saiki, Mitiko; Alves, Edson R.; Vasconcellos, M.B.A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)], e-mail: mitiko@ipen.br, e-mail: eralves@ipen.br, e-mail: mbvascon@ipen.br; Sumita, Nairo M. [Universidade de Sao Paulo (USP), SP (Brazil). Hospital das Clinicas.Central Lab. Division and Laboratories of Medical Investigation (LIM-03)], e-mail: dlc.bioquimica@hcnet.usp.br; Jaluul, Omar; Jacob-Filho, Wilson [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Medicina], e-mail: jaluul@uol.com.br, wiljac@usp.br

2009-07-01

In this study, serum zinc and lipoprotein concentrations were determined in order to assess the health status of an elderly population residing in Sao Paulo city, SP, Brazil. This population consisted of elderly considered healthy and participating of a 'Successful Ageing' program of the Sao Paulo University Medical School. Fasting blood samples were collected from 87 elderly individuals (63 females and 24 males) aged 60-91 and mean age of 72 +- 7 years. Zn concentrations were determined by neutron activation analysis at the IPEN/CNEN/ SP and, the lipoprotein (HDL, LDL and total cholesterol) concentrations were determined using routine analysis methods of the Central Laboratory Division, Hospital das Clinicas, FMUSP. Results obtained for Zn indicated that all the individuals presented this element within the recommended value. For total cholesterol and HDL-cholesterol concentrations, 96 % of elderly presented levels within the desired range but for LDL cholesterol concentrations only about 70.0 % of individuals were in the desired range. Serum concentration of Zn were positively correlated to LDL-cholesterol levels (correlation coefficient r = 0.21, p < 0.06). Furthermore, the ratios of [HDL-cholesterol] / [LDL-cholesterol] were negatively correlated with Zn concentrations (r = - 0.234, p < 0.04). The positive correlation found between the serum concentrations of Zn and LDL-cholesterol indicates the possible effect of this element in serum lipoprotein profiles. Thus ,these findings suggest that more investigations should be conducted on Zn supplementation in elderly subjects with cardiovascular diseases. (author)

Correlation studies between serum concentrations of zinc and lipoproteins

International Nuclear Information System (INIS)

Saiki, Mitiko; Alves, Edson R.; Vasconcellos, M.B.A.; Sumita, Nairo M.; Jaluul, Omar; Jacob-Filho, Wilson

2009-01-01

In this study, serum zinc and lipoprotein concentrations were determined in order to assess the health status of an elderly population residing in Sao Paulo city, SP, Brazil. This population consisted of elderly considered healthy and participating of a 'Successful Ageing' program of the Sao Paulo University Medical School. Fasting blood samples were collected from 87 elderly individuals (63 females and 24 males) aged 60-91 and mean age of 72 +- 7 years. Zn concentrations were determined by neutron activation analysis at the IPEN/CNEN/ SP and, the lipoprotein (HDL, LDL and total cholesterol) concentrations were determined using routine analysis methods of the Central Laboratory Division, Hospital das Clinicas, FMUSP. Results obtained for Zn indicated that all the individuals presented this element within the recommended value. For total cholesterol and HDL-cholesterol concentrations, 96 % of elderly presented levels within the desired range but for LDL cholesterol concentrations only about 70.0 % of individuals were in the desired range. Serum concentration of Zn were positively correlated to LDL-cholesterol levels (correlation coefficient r = 0.21, p < 0.06). Furthermore, the ratios of [HDL-cholesterol] / [LDL-cholesterol] were negatively correlated with Zn concentrations (r = - 0.234, p < 0.04). The positive correlation found between the serum concentrations of Zn and LDL-cholesterol indicates the possible effect of this element in serum lipoprotein profiles. Thus ,these findings suggest that more investigations should be conducted on Zn supplementation in elderly subjects with cardiovascular diseases. (author)

Correlations between the BDI and CES-D in a Sample of Adolescent Mothers.

Science.gov (United States)

Wilcox, Holly; Field, Tiffany; Prodromidis, Margarita; Scafidi, Frank

1998-01-01

The adequacy of the Beck Depression Inventory (BDI) and Center for Epidemiological Studies-Depression (CES-D) as screening instruments for adolescent depression is examined. Both are correlated with the Diagnostic Interview Schedule for Children, a clinical measure. BDI correlates more highly with Major Depression subscale, CES-D to Dysthymia…

Hidden cross-correlation patterns in stock markets based on permutation cross-sample entropy and PCA

Science.gov (United States)

Lin, Aijing; Shang, Pengjian; Zhong, Bo

2014-12-01

In this article, we investigate the hidden cross-correlation structures in Chinese stock markets and US stock markets by performing PCSE combined with PCA approach. It is suggested that PCSE can provide a more faithful and more interpretable description of the dynamic mechanism between time series than cross-correlation matrix. We show that this new technique can be adapted to observe stock markets especially during financial crisis. In order to identify and compare the interactions and structures of stock markets during financial crisis, as well as in normal periods, all the samples are divided into four sub-periods. The results imply that the cross-correlations between Chinese group are stronger than the US group in the most sub-periods. In particular, it is likely that the US stock markets are more integrated with each other during global financial crisis than during Asian financial crisis. However, our results illustrate that Chinese stock markets are not immune from the global financial crisis, although less integrated with other markets if they are compared with US stock markets.

Leptine: an hormone secreted by adipose tissue. First study in Uruguayan population sample

International Nuclear Information System (INIS)

Pisabarro, Raul; Irrazabal, Ernesto; Recalde, Alicia; Barrios, Enrique; Arocena, Beatriz; Garcia Loriente, Jose Maria; Lorenzo Bonifazio, Juan

1999-01-01

The recent discovery of leptine, an hormone secreted by adipose tissue which modulates the energetic expenditure has signified a gigantic advance in studying obesity facts. In spite of a recent description of absence of leptine in humans, the obesity human model answers to leptine resistance. In this paper, we revise the actual concepts and show leptine values of a sample of 101 middle aged uruguayans, male and female, of normal weight and over weighted (table 1), correlated with corporal mass index (CMI) as an indirect measure of total body fat and waist diameter as an indirect measure of visceral fat, and hips (periferical fat). Bioimpedance studies were carried out to get the corporal composition. Results: good correlation between corporal fat and leptine, but fat distribution was not found representative. All in all, this data set confirms the correlation between leptine and total body fat mass

Whole genome transcript profiling from fingerstick blood samples: a comparison and feasibility study

Directory of Open Access Journals (Sweden)

Williams Adam R

2009-12-01

Full Text Available Abstract Background Whole genome gene expression profiling has revolutionized research in the past decade especially with the advent of microarrays. Recently, there have been significant improvements in whole blood RNA isolation techniques which, through stabilization of RNA at the time of sample collection, avoid bias and artifacts introduced during sample handling. Despite these improvements, current human whole blood RNA stabilization/isolation kits are limited by the requirement of a venous blood sample of at least 2.5 mL. While fingerstick blood collection has been used for many different assays, there has yet to be a kit developed to isolate high quality RNA for use in gene expression studies from such small human samples. The clinical and field testing advantages of obtaining reliable and reproducible gene expression data from a fingerstick are many; it is less invasive, time saving, more mobile, and eliminates the need of a trained phlebotomist. Furthermore, this method could also be employed in small animal studies, i.e. mice, where larger sample collections often require sacrificing the animal. In this study, we offer a rapid and simple method to extract sufficient amounts of high quality total RNA from approximately 70 μl of whole blood collected via a fingerstick using a modified protocol of the commercially available Qiagen PAXgene RNA Blood Kit. Results From two sets of fingerstick collections, about 70 uL whole blood collected via finger lancet and capillary tube, we recovered an average of 252.6 ng total RNA with an average RIN of 9.3. The post-amplification yields for 50 ng of total RNA averaged at 7.0 ug cDNA. The cDNA hybridized to Affymetrix HG-U133 Plus 2.0 GeneChips had an average % Present call of 52.5%. Both fingerstick collections were highly correlated with r2 values ranging from 0.94 to 0.97. Similarly both fingerstick collections were highly correlated to the venous collection with r2 values ranging from 0.88 to 0

High precision studies of directional correlations

International Nuclear Information System (INIS)

El-khosht, M.

1980-01-01

Two applications of the method of directional correlations are described. The first part deals with gamma-gamma directional correlations measurements. A total of 27 cascades have been studied in 97 Tc, 206 Pb and 206 Bi. Information is obtained on the angular momenta of levels, multipolarities of electromagnetic transitions and further, reduced transition probabilities. The later part of this thesis describes a determination of anisotropic directional correlation between gamma-rays and LX-rays in 160 Dy. To the authors' knowledge this is the first observation of an anisotropic correlation between gamma rays and X-rays following internal conversion. (Auth.)

Correlation study of air pollution and cardio-respiratory diseases through NAA of an atmospheric pollutant biomonitor

International Nuclear Information System (INIS)

Saiki, M.; Alves, E.R.; Genezini, F.A.; Santos, J.O.; Marcelli, M.P.; Saldiva, P.H.N.

2014-01-01

In this study neutron activation analysis was applied to analyze lichen samples used as atmospheric pollutant biomonitors in order to verify if there is correlation between air pollution and its effects on the cardio respiratory system. Canoparmelia texana lichenized fungii species was chosen for passive biomonitoring of atmospheric pollutants. The population group selected for this study was adults over 45 years. Lichen samples collected in Sao Paulo city were cleaned, freeze-dried and ground for the analyses. Aliquots of samples were irradiated at the IEA-R1 nuclear research reactor for short and long periods along with synthetic element standards. The induced gamma activities of the samples and standards were measured using a gamma ray spectrometer with an HPGe detector and the concentrations of As, Ba, Br, Ca, Cd, Cl, Co, Cr, Cs, Fe, Hf, K, Mg, Mn, Na, Rb, Sb, Sc, Se,Th, V, Zn and lanthanides were determined. For quality control of the results, certified reference materials were analyzed together. Mortality data for the population due to cardio-respiratory diseases were obtained from the database of the Secretariat of Health of the Sao Paulo Municipality for the years 2005-2009. Results obtained point to vehicular and industrial emissions as the origins of pollutants in Sao Paulo city. The statistical treatment of Pearson's correlation applied to the results of lichen element concentrations and mortality rates indicated significant positive correlation for the elements Co, Mn and Zn for adults. (author)

Prostate specific antigen in a community-based sample of men without prostate cancer: Correlations with prostate volume, age, body mass index, and symptoms of prostatism

NARCIS (Netherlands)

J.L.H.R. Bosch (Ruud); W.C.J. Hop (Wim); C.H. Bangma (Chris); W.J. Kirkels (Wim); F.H. Schröder (Fritz)

1995-01-01

textabstractThe correlation between both prostate specific antigen levels (PSA) and prostate specific antigen density (PSAD) and age, prostate volume parameters, body mass index, and the International Prostate Symptom Score (IPSS) were studied in a community‐based population. A sample of 502 men

Self-Concept in Student Learning and Motivation Truant : Descriptive-Correlational Studies

Directory of Open Access Journals (Sweden)

Erlina Harahap

2017-08-01

Full Text Available This research is aimed describ the learning motivation and self-concept of students who truant. This study used a descriptive quantitative method. The research conducted by the students of SMAN 5 Padangsidimpuan in the period of 2015/2016 with the total of the population was 420 students. Amount of research sample was 36 students and had been chosen by using purposive sampling technique. An instrument employed in this study was a Likert-scaled questionnaire. Data were analyzed by using percentage technique and the relationship between the two variables was analyzed by using nonparametric statistic, that is Spearman’s Coefficient of Rank Correlation. Results of this research are just like the following: 1 participants’ level of achievement on self-concept of students who truant is about 69,8%, 2 participants’ level of achievement on learning motivation of students who truant is about 69,2%, and 3 correlation coefficient of self-concept and learning motivation of students who truant is about 0,581. Therefore, it can be concluded that students who truancy have very low self-concept and learning motivation, and there is a significant relationship between self-concept and learning motivation. The implication in guidance counseling services is to create a service program which can increase self-concept and be learning motivation of students who truant

COMPARATIVE STUDY OF ENDOMETRIAL SAMPLING USING PIPELLE WITH HYSTEROSCOPIC-GUIDED BIOPSY

Directory of Open Access Journals (Sweden)

Nalina S

2017-07-01

Full Text Available BACKGROUND Hysteroscopic-guided biopsy is the gold standard for endometrial sampling, but it carries risk of general anaesthesia, infection and perforation, whereas Pipelle does not require anaesthesia or cervical dilatation and it allows outpatient and painless endometrial sampling. The aim of the study is to determine the reliability and accuracy of Pipelle aspiration in acquiring an adequate and representative endometrial sample and to compare its histopathology with hysteroscopic-directed biopsy. MATERIALS AND METHODS A prospective observational comparative study evaluating the role of Pipelle aspiration as an outpatient procedure in endometrial sampling of perimenopausal women with AUB. 150 perimenopausal women with clinical diagnosis of abnormal uterine bleeding were selected from the Gynaecology OPD of IOG, Chennai, between October 2014 and September 2015. They were subjected to endometrial sampling by Pipelle followed by hysteroscopic-directed biopsy. The efficacy of Pipelle was determined by correlating the histopathological results obtained from it and the hysteroscopic-directed biopsy. RESULTS The histopathology of the endometrium obtained using Pipelle’s curette showed a sensitivity of 93%, specificity of 90% in the detection of abnormal findings with PPV of 88% and NPV of 94%. However, accuracy of Pipelle is found to be less in the diagnosis of polyps and submucous fibroids with accuracy of nearing 100% when using hysteroscopy. CONCLUSION Pipelle endometrial sampling is convenient, easy, painless and safe in obtaining an adequate sample for histopathology with high sensitivity and specificity for endometrial pathologies and endometrial carcinoma.

Jordanian dialysis patients' perceived exercise benefits and barriers: a correlation study.

Science.gov (United States)

Darawad, Muhammad W; Khalil, Amani A

2013-01-01

To investigate Jordanian end-stage renal disease (ESRD)patients' perceived exercise benefits and barriers, and their correlation with patients' demographic variables and dialysis measures. A descriptive correlational study was conducted using cross-sectional survey, using a convenience sample of 190 ESRD dialyzed patients who were recruited from eight hospitals in Jordan. Participants significantly perceived exercise benefits (M= 2.88/4, SD± .67) higher than barriers (M= 2.66, SD± .62). The most frequent perceived exercise benefits were preventing muscular atrophy and improving mood, whereas tiredness and lower-extremity fatigue were the most frequent exercise barriers. Finally, acceptable values of Cronbach's Alpha were revealed for perceived exercise subscale, barriers subscale, and total scale (α= .88, .81, and .70, respectively). Participants focused more on exercise benefits than barriers, and on direct exercise benefits and barriers than the indirect. The results of this study have important implications for the efforts that aim at improving ESRD patients' exercise behaviors. © 2013 Association of Rehabilitation Nurses.

A Mid-IR Multivariate Analysis Study on the Gross Calorific Value in Longleaf Pine: Impact on Correlations with Lignin and Extractive Contents

Science.gov (United States)

Chi-Leung So; Thomas L. Eberhardt

2013-01-01

Twenty 70-year-old longleaf pine trees from a spacing, thinning, and pruning study were harvested, from which samples were analyzed for gross calorific value (GCV). A strong correlation was found between GCV and extractive contents for the unextracted wood samples. Although lignin content should impact GCV, no correlation was found between the variation in GCV with...

Prevalence and correlates of unhealthy weight control behaviors: findings from the national longitudinal study of adolescent health

OpenAIRE

Stephen, Eric M; Rose, Jennifer S; Kenney, Lindsay; Rosselli-Navarra, Francine; Weissman, Ruth Striegel

2014-01-01

Background A recent study examined the prevalence, clinical correlates, age trends, and stability of unhealthy weight control behaviors (UWCB; purging and diet pill use) in a nationally representative sample of Norwegian boys and girls. The purpose of this study was to provide similar, comparative analyses for a nationally representative sample of American youth. Methods Data were extracted from the restricted use data files of survey Waves I, II, and III of the National Longitudinal Study of...

The prevalence and correlates of depression, anxiety, and stress in a sample of college students.

Science.gov (United States)

Beiter, R; Nash, R; McCrady, M; Rhoades, D; Linscomb, M; Clarahan, M; Sammut, S

2015-03-01

Over the past four years, the Franciscan University Counseling Center has reported a 231% increase in yearly visits, as well as a 173% increase in total yearly clients. This trend has been observed at many universities as mental health issues pose significant problems for many college students. The objective of this study was to investigate potential correlates of depression, anxiety, and stress in a sample of college students. The final analyzed sample consisted of 374 undergraduate students between the ages of 18 and 24 attending Franciscan University, Steubenville, Ohio. Subjects completed a survey consisting of demographic questions, a section instructing participants to rate the level of concern associated with challenges pertinent to daily life (e.g. academics, family, sleep), and the 21 question version of the Depression Anxiety Stress Scale (DASS21). The results indicated that the top three concerns were academic performance, pressure to succeed, and post-graduation plans. Demographically, the most stressed, anxious, and depressed students were transfers, upperclassmen, and those living off-campus. With the propensity for mental health issues to hinder the success of college students, it is vital that colleges continually evaluate the mental health of their students and tailor treatment programs to specifically target their needs. Copyright © 2014 Elsevier B.V. All rights reserved.

The study of combining Latin Hypercube Sampling method and LU decomposition method (LULHS method) for constructing spatial random field

Science.gov (United States)

WANG, P. T.

2015-12-01

Groundwater modeling requires to assign hydrogeological properties to every numerical grid. Due to the lack of detailed information and the inherent spatial heterogeneity, geological properties can be treated as random variables. Hydrogeological property is assumed to be a multivariate distribution with spatial correlations. By sampling random numbers from a given statistical distribution and assigning a value to each grid, a random field for modeling can be completed. Therefore, statistics sampling plays an important role in the efficiency of modeling procedure. Latin Hypercube Sampling (LHS) is a stratified random sampling procedure that provides an efficient way to sample variables from their multivariate distributions. This study combines the the stratified random procedure from LHS and the simulation by using LU decomposition to form LULHS. Both conditional and unconditional simulations of LULHS were develpoed. The simulation efficiency and spatial correlation of LULHS are compared to the other three different simulation methods. The results show that for the conditional simulation and unconditional simulation, LULHS method is more efficient in terms of computational effort. Less realizations are required to achieve the required statistical accuracy and spatial correlation.

Sample size in qualitative interview studies

DEFF Research Database (Denmark)

Malterud, Kirsti; Siersma, Volkert Dirk; Guassora, Ann Dorrit Kristiane

2016-01-01

Sample sizes must be ascertained in qualitative studies like in quantitative studies but not by the same means. The prevailing concept for sample size in qualitative studies is “saturation.” Saturation is closely tied to a specific methodology, and the term is inconsistently applied. We propose...... the concept “information power” to guide adequate sample size for qualitative studies. Information power indicates that the more information the sample holds, relevant for the actual study, the lower amount of participants is needed. We suggest that the size of a sample with sufficient information power...... and during data collection of a qualitative study is discussed....

A study of the correlation between self-confidence and professional achievement of designers

Directory of Open Access Journals (Sweden)

Chen Rain

2017-01-01

Full Text Available This study mainly investigated which mental state of designers, self-confidence or sense of inferiority, has positive effects on professional design achievement. This study attempted to find if there is correlation between designers’ self-confidence or sense of inferiority and their professional achievement. With regard to the tendency of designers’ psychological state, the Rosenberg Self-Esteem Scale was used to measure designers’ selfconfidence, and statistical computations were made based on gathered data. This study used correlation analysis to find if confidence level of 46 seniors of Design Department is relevant to their professional achievement. The results of the study showed that confidence level of designers has a slight correlation to professional achievement. Factors leading to the study’s findings may be the small amount of sample analyzed or may be the reason that the Rosenberg Self-Esteem Scale only detected the current level of self-confidence and could not give a proper feedback on designers’ self-confidence during the entire semester. In the future, the results of this study can be considered as a pre-test experiment for a more complete study, and it is expected that results of the study can be for design educators’ reference.

The correlation between thought-action fusion and religiosity in a normal sample.

Science.gov (United States)

Rassin, E; Koster, E

2003-03-01

Thought-action fusion (TAF) refers to a set of two cognitive biases that are thought to contribute to the inflation of feelings of responsibility for one's own thoughts, and thus to the development of obsession. Therefore, insight into the origins of TAF is a clinically relevant research topic. The present study examined the association between religiosity and TAF. Undergraduate students (N=100) completed questionnaires concerning religion, TAF and obsessive-compulsive complaints. Results indicate that religiosity is, indeed, correlated with certain aspects of TAF. Furthermore, correlational patterns differed between Catholic and Protestant subsamples.

Environmental DNA from Seawater Samples Correlate with Trawl Catches of Subarctic, Deepwater Fishes.

Directory of Open Access Journals (Sweden)

Philip Francis Thomsen

Full Text Available Remote polar and deepwater fish faunas are under pressure from ongoing climate change and increasing fishing effort. However, these fish communities are difficult to monitor for logistic and financial reasons. Currently, monitoring of marine fishes largely relies on invasive techniques such as bottom trawling, and on official reporting of global catches, which can be unreliable. Thus, there is need for alternative and non-invasive techniques for qualitative and quantitative oceanic fish surveys. Here we report environmental DNA (eDNA metabarcoding of seawater samples from continental slope depths in Southwest Greenland. We collected seawater samples at depths of 188-918 m and compared seawater eDNA to catch data from trawling. We used Illumina sequencing of PCR products to demonstrate that eDNA reads show equivalence to fishing catch data obtained from trawling. Twenty-six families were found with both trawling and eDNA, while three families were found only with eDNA and two families were found only with trawling. Key commercial fish species for Greenland were the most abundant species in both eDNA reads and biomass catch, and interpolation of eDNA abundances between sampling sites showed good correspondence with catch sizes. Environmental DNA sequence reads from the fish assemblages correlated with biomass and abundance data obtained from trawling. Interestingly, the Greenland shark (Somniosus microcephalus showed high abundance of eDNA reads despite only a single specimen being caught, demonstrating the relevance of the eDNA approach for large species that can probably avoid bottom trawls in most cases. Quantitative detection of marine fish using eDNA remains to be tested further to ascertain whether this technique is able to yield credible results for routine application in fisheries. Nevertheless, our study demonstrates that eDNA reads can be used as a qualitative and quantitative proxy for marine fish assemblages in deepwater oceanic

Strength and deformability of hollow concrete blocks: correlation of block and cylindrical sample test results

OpenAIRE

Barbosa, C. S.; Hanai, J.B.

2009-01-01

This paper deals with correlations among mechanical properties of hollow blocks and those of concrete used to make them. Concrete hollow blocks and test samples were moulded with plastic consistency concrete, to assure the same material in all cases, in three diferente levels of strength (nominally 10 N/mm², 20 N/mm² and 30 N/mm²). The mechanical properties and structural behaviour in axial compression and tension tests were determined by standard tests in blocks and cylinders. Stress and str...

Health Correlates of Insomnia Symptoms and Comorbid Mental Disorders in a Nationally Representative Sample of US Adolescents

Science.gov (United States)

Blank, Madeleine; Zhang, Jihui; Lamers, Femke; Taylor, Adrienne D.; Hickie, Ian B.; Merikangas, Kathleen R.

2015-01-01

Study Objectives: To estimate the prevalence and health correlates of insomnia symptoms and their association with comorbid mental disorders in a nationally representative sample of adolescents in the United States. Design: National representative cross-sectional study. Setting: Population-based sample from the US adolescents. Measurements and Results: A total of 6,483 individuals aged between 13–18 y in the National Comorbidity Survey-Adolescent Supplement (NCS-A) with both individual and parental reports of mental health were included in this study. Participants were classified with insomnia symptoms if they reported difficulty initiating sleep, difficulty maintaining sleep, and/or early morning awakening, nearly every day for at least 2 w in the past year. Nearly one-third of adolescents reported insomnia symptoms for at least 2 w during the previous year. Hispanic and black youth were significantly more likely to report insomnia symptoms (42.0% and 41.3%, respectively) than non-Hispanic white youth (30.4%). Adolescents with insomnia symptoms were at a higher risk for all classes of mental disorders {odds ratio [OR] (95% confidence interval [CI]: 3.4 (2.9–4.0)} including mood, anxiety, behavioral, substance use, and eating disorders, suicidality [OR (95% CI): 2.63 (1.34–5.16)], poor perceived mental health [OR (95% CI): 2.01 (1.02–3.96)], chronic medical conditions [OR (95% CI): 1.94 (1.55–2.43)], smoking [OR (95% CI: 2.60 (1.00–6.72)], and obesity [OR (95% CI: 1.46 (1.10–1.93)] than those without insomnia symptoms. Adolescents with insomnia symptoms and comorbid mental disorders manifested even greater rates of these indicators of negative health behaviors and disorders than those with mental disorders alone (P Insomnia symptoms are reported by one-third of adolescents in the general population. Insomnia symptoms, even in the absence of concomitant depression or other mental disorders, are associated with serious health conditions, risk factors

Uncertainty Determination Methodology, Sampling Maps Generation and Trend Studies with Biomass Thermogravimetric Analysis

Science.gov (United States)

Pazó, Jose A.; Granada, Enrique; Saavedra, Ángeles; Eguía, Pablo; Collazo, Joaquín

2010-01-01

This paper investigates a method for the determination of the maximum sampling error and confidence intervals of thermal properties obtained from thermogravimetric analysis (TG analysis) for several lignocellulosic materials (ground olive stone, almond shell, pine pellets and oak pellets), completing previous work of the same authors. A comparison has been made between results of TG analysis and prompt analysis. Levels of uncertainty and errors were obtained, demonstrating that properties evaluated by TG analysis were representative of the overall fuel composition, and no correlation between prompt and TG analysis exists. Additionally, a study of trends and time correlations is indicated. These results are particularly interesting for biomass energy applications. PMID:21152292

Sampling strategies to measure the prevalence of common recurrent infections in longitudinal studies

Directory of Open Access Journals (Sweden)

Luby Stephen P

2010-08-01

Full Text Available Abstract Background Measuring recurrent infections such as diarrhoea or respiratory infections in epidemiological studies is a methodological challenge. Problems in measuring the incidence of recurrent infections include the episode definition, recall error, and the logistics of close follow up. Longitudinal prevalence (LP, the proportion-of-time-ill estimated by repeated prevalence measurements, is an alternative measure to incidence of recurrent infections. In contrast to incidence which usually requires continuous sampling, LP can be measured at intervals. This study explored how many more participants are needed for infrequent sampling to achieve the same study power as frequent sampling. Methods We developed a set of four empirical simulation models representing low and high risk settings with short or long episode durations. The model was used to evaluate different sampling strategies with different assumptions on recall period and recall error. Results The model identified three major factors that influence sampling strategies: (1 the clustering of episodes in individuals; (2 the duration of episodes; (3 the positive correlation between an individual's disease incidence and episode duration. Intermittent sampling (e.g. 12 times per year often requires only a slightly larger sample size compared to continuous sampling, especially in cluster-randomized trials. The collection of period prevalence data can lead to highly biased effect estimates if the exposure variable is associated with episode duration. To maximize study power, recall periods of 3 to 7 days may be preferable over shorter periods, even if this leads to inaccuracy in the prevalence estimates. Conclusion Choosing the optimal approach to measure recurrent infections in epidemiological studies depends on the setting, the study objectives, study design and budget constraints. Sampling at intervals can contribute to making epidemiological studies and trials more efficient, valid

Uranium, radium and radon exhalation study in some soil samples using track etch technique

International Nuclear Information System (INIS)

Harmanjit, Singh; Joga, Singh; Surinder, Singh; Bajwa, B.S.

2006-01-01

Full text of publication follows: Uranium, radium concentration and radon exhalation rates have been determined in the soil samples collected from some areas of Punjab using the L.R.-115 nuclear track detectors. Radium concentration in these samples has been found to be varying from 0.80 to 5.34 Bq Kg-1. The radon exhalation rate in these samples has been found to be varying from 0.99 to 6.60 mBq Kg -1 h -1 (32.82 to 218.49 mBqm -2 h -1 ). A good correlation has been observed between radon exhalation rate and radium concentration observed in the soil samples. The uranium concentration in all these samples is being carried out and the other correlations will also be established. (authors)

Estimation of the simple correlation coefficient.

Science.gov (United States)

Shieh, Gwowen

2010-11-01

This article investigates some unfamiliar properties of the Pearson product-moment correlation coefficient for the estimation of simple correlation coefficient. Although Pearson's r is biased, except for limited situations, and the minimum variance unbiased estimator has been proposed in the literature, researchers routinely employ the sample correlation coefficient in their practical applications, because of its simplicity and popularity. In order to support such practice, this study examines the mean squared errors of r and several prominent formulas. The results reveal specific situations in which the sample correlation coefficient performs better than the unbiased and nearly unbiased estimators, facilitating recommendation of r as an effect size index for the strength of linear association between two variables. In addition, related issues of estimating the squared simple correlation coefficient are also considered.

Global study of quadrupole correlation effects

International Nuclear Information System (INIS)

Bender, M.; Bertsch, G.F.; Heenen, P.-H.

2006-01-01

We discuss the systematics of ground-state quadrupole correlations of binding energies and mean-square charge radii for all even-even nuclei, from 16 O up to the superheavies, for which data are available. To that aim we calculate their correlated J=0 ground state by means of the angular-momentum and particle-number projected generator coordinate method, using the axial mass quadrupole moment as the generator coordinate and self-consistent mean-field states restricted only by axial, parity, and time-reversal symmetries. The calculation is performed within the framework of a nonrelativistic self-consistent mean-field model by use of the same Skyrme interaction SLy4 and to a density-dependent pairing force to generate the mean-field configurations and to mix them. These are the main conclusions of our study: (i) The quadrupole correlation energy varies between a few 100 keV and about 5.5 MeV. It is affected by shell closures, but varies only slightly with mass and asymmetry. (ii) Projection on angular momentum J=0 provides the major part of the energy gain of up to about 4 MeV; all nuclei in the study, including doubly magic ones, gain energy by deformation. (iii) The mixing of projected states with different intrinsic axial deformations adds a few 100 keV up to 1.5 MeV to the correlation energy. (iv) Typically nuclei below mass A≤60 have a larger correlation energy than static deformation energy whereas the heavier deformed nuclei have larger static deformation energy than correlation energy. (v) Inclusion of the quadrupole correlation energy improves the description of mass systematics, particularly around shell closures, and of differential quantities, namely two-nucleon separation energies and two-nucleon gaps. The correlation energy provides an explanation of 'mutually enhanced magicity'. (vi) The correlation energy tends to decrease the shell effect on binding energies around magic numbers, but the magnitude of the suppression is not large enough to explain

Correlation of the levels of glycosaminoglycans between urine and dried urine in filter paper samples and their stability over time under different storage temperatures.

Science.gov (United States)

Breier, Ana Carolina; Cé, Jaqueline; Coelho, Janice Carneiro

2014-06-10

Mucopolysaccharidoses (MPSs) are a group of lysosomal storage diseases caused by the deficiency/absence of enzymes which catalyze the degradation of glycosaminoglycans (GAGs). The use of biological samples dried on filter paper has been increasing because it makes it easy to ship them to reference laboratories. Urinary GAGs are the main biomarkers of MPS and, thus, we studied the correlations of determinations to GAGs and creatinine, as well as compared the GAGs' profile on electrophoresis, between urine and dried urine in filter paper (DUFP) samples. We also assessed the GAG stability over time under different storage temperatures. We quantified the GAG concentration in both sample types and compared the results by Pearson correlation. The results were very similar, with r=0.97 for creatinine and with r=0.94 and r=0.98 for GAGs for controls and patients, respectively, with similar electrophoretic profiles. The GAG stability in DUFP was up to 30days at -20, 4, and 25°C and up to 21days at 37°C. Our proposal assessed urinary GAGs in DUFP and concluded that these samples can be used in the investigation of MPS, replacing urine samples in neonatal screening and monitoring of therapies, due to ease of transportation and storage. Copyright © 2014 Elsevier B.V. All rights reserved.

[Correlation between demyelinating lesions and executive function decline in a sample of Mexican patients with multiple sclerosis].

Science.gov (United States)

Aldrete Cortez, V R; Duriez-Sotelo, E; Carrillo-Mora, P; Pérez-Zuno, J A

2013-09-01

Multiple Sclerosis (MS) is characterised by several neurological symptoms including cognitive impairment, which has recently been the subject of considerable study. At present, evidence pointing to a correlation between lesion characteristics and specific cognitive impairment is not conclusive. To investigate the presence of a correlation between the characteristics of demyelinating lesions and performance of basic executive functions in a sample of MS patients. We included 21 adult patients with scores of 0 to 5 on the Kurtzke scale and no exacerbations of the disease in at least 3 months prior to the evaluation date. They completed the Stroop test and the Wisconsin Card Sorting Test (WCST). The location of the lesions was determined using magnetic resonance imaging (MRI) performed by a blinded expert in neuroimaging. Demyelinating lesions were more frequently located in the frontal and occipital lobes. The Stroop test showed that as cognitive demand increased on each of the sections in the test, reaction time and number of errors increased. On the WCST, 33.33% of patients registered as having moderate cognitive impairment. No correlation could be found between demyelinating lesion characteristics (location, size, and number) and patients' scores on the tests. Explanations of the causes of cognitive impairment in MS should examine a variety of biological, psychological, and social factors instead of focusing solely on demyelinating lesions. Copyright © 2012 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

Cluster designs to assess the prevalence of acute malnutrition by lot quality assurance sampling: a validation study by computer simulation.

Science.gov (United States)

Olives, Casey; Pagano, Marcello; Deitchler, Megan; Hedt, Bethany L; Egge, Kari; Valadez, Joseph J

2009-04-01

Traditional lot quality assurance sampling (LQAS) methods require simple random sampling to guarantee valid results. However, cluster sampling has been proposed to reduce the number of random starting points. This study uses simulations to examine the classification error of two such designs, a 67x3 (67 clusters of three observations) and a 33x6 (33 clusters of six observations) sampling scheme to assess the prevalence of global acute malnutrition (GAM). Further, we explore the use of a 67x3 sequential sampling scheme for LQAS classification of GAM prevalence. Results indicate that, for independent clusters with moderate intracluster correlation for the GAM outcome, the three sampling designs maintain approximate validity for LQAS analysis. Sequential sampling can substantially reduce the average sample size that is required for data collection. The presence of intercluster correlation can impact dramatically the classification error that is associated with LQAS analysis.

A Study of Correlations Between Identified Charged Hadrons in Hadronic Z0 Decays

International Nuclear Information System (INIS)

Burrows, Phil

2000-01-01

The authors present a preliminary study of correlations in rapidity between pairs of identified charged pions, kaons and protons using the entire SLD data sample of 550,000 hadronic Z 0 decays. Short range charge correlations are observed between all combinations of these hadron species, indicating local conservation of quantum numbers and charge ordering in the jet fragmentation process. The rapidity range of this effect is found to be independent of particle momentum. A strong long-range K + -K - correlation is observed at high-momentum and weaker long-range pi + -pi - , pi + -K - p-K - and p anti-p correlations are observed in light flavor events, providing new information on leading particle production in u, d and s jets. The long-range correlations observed in c anti-c and b anti-b events are markedly different and consistent with expectations based on known decay properties of the leading heavy hadrons. In addition, the SLC electron beam polarization is used to tag the quark hemisphere in each event, allowing the first study of rapidities signed such that positive rapidity is along the quark rather than antiquark direction. Distributions of ordered differences in signed rapidity between pairs of particles provide a direct probe of quantum number ordering along the quark-antiquark axis and other new insights into the fragmentation process

A comparison of maximum likelihood and other estimators of eigenvalues from several correlated Monte Carlo samples

International Nuclear Information System (INIS)

Beer, M.

1980-01-01

The maximum likelihood method for the multivariate normal distribution is applied to the case of several individual eigenvalues. Correlated Monte Carlo estimates of the eigenvalue are assumed to follow this prescription and aspects of the assumption are examined. Monte Carlo cell calculations using the SAM-CE and VIM codes for the TRX-1 and TRX-2 benchmark reactors, and SAM-CE full core results are analyzed with this method. Variance reductions of a few percent to a factor of 2 are obtained from maximum likelihood estimation as compared with the simple average and the minimum variance individual eigenvalue. The numerical results verify that the use of sample variances and correlation coefficients in place of the corresponding population statistics still leads to nearly minimum variance estimation for a sufficient number of histories and aggregates

Intermittency and correlations in hadronic $Z^0$ decays

CERN Document Server

Abbiendi, G.; Alexander, G.; Allison, John; Altekamp, N.; Anderson, K.J.; Anderson, S.; Arcelli, S.; Asai, S.; Ashby, S.F.; Axen, D.; Azuelos, G.; Ball, A.H.; Barberio, E.; Barlow, Roger J.; Batley, J.R.; Baumann, S.; Bechtluft, J.; Behnke, T.; Bell, Kenneth Watson; Bella, G.; Bellerive, A.; Bentvelsen, S.; Bethke, S.; Betts, S.; Biebel, O.; Biguzzi, A.; Blobel, V.; Bloodworth, I.J.; Bock, P.; Bohme, J.; Bonacorsi, D.; Boutemeur, M.; Braibant, S.; Bright-Thomas, P.; Brigliadori, L.; Brown, Robert M.; Burckhart, H.J.; Capiluppi, P.; Carnegie, R.K.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, David G.; Chrisman, D.; Ciocca, C.; Clarke, P.E.L.; Clay, E.; Cohen, I.; Conboy, J.E.; Cooke, O.C.; Couyoumtzelis, C.; Coxe, R.L.; Cuffiani, M.; Dado, S.; Dallavalle, G.Marco; Davis, R.; De Jong, S.; de Roeck, A.; Dervan, P.; Desch, K.; Dienes, B.; Dixit, M.S.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Estabrooks, P.G.; Etzion, E.; Fabbri, F.; Fanfani, A.; Fanti, M.; Faust, A.A.; Fiedler, F.; Fierro, M.; Fleck, I.; Folman, R.; Frey, A.; Furtjes, A.; Futyan, D.I.; Gagnon, P.; Gary, J.W.; Gascon, J.; Gascon-Shotkin, S.M.; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Gibson, V.; Gibson, W.R.; Gingrich, D.M.; Glenzinski, D.; Goldberg, J.; Gorn, W.; Grandi, C.; Graham, K.; Gross, E.; Grunhaus, J.; Gruwe, M.; Hanson, G.G.; Hansroul, M.; Hapke, M.; Harder, K.; Harel, A.; Hargrove, C.K.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Herndon, M.; Herten, G.; Heuer, R.D.; Hildreth, M.D.; Hill, J.C.; Hobson, P.R.; Hoch, M.; Hocker, James Andrew; Hoffman, Kara Dion; Homer, R.J.; Honma, A.K.; Horvath, D.; Hossain, K.R.; Howard, R.; Huntemeyer, P.; Igo-Kemenes, P.; Imrie, D.C.; Ishii, K.; Jacob, F.R.; Jawahery, A.; Jeremie, H.; Jimack, M.; Jones, C.R.; Jovanovic, P.; Junk, T.R.; Kanzaki, J.; Karlen, D.; Kartvelishvili, V.; Kawagoe, K.; Kawamoto, T.; Kayal, P.I.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kim, D.H.; Klier, A.; Kobayashi, T.; Kobel, M.; Kokott, T.P.; Kolrep, M.; Komamiya, S.; Kowalewski, Robert V.; Kress, T.; Krieger, P.; von Krogh, J.; Kuhl, T.; Kyberd, P.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Lauber, J.; Lautenschlager, S.R.; Lawson, I.; Layter, J.G.; Lazic, D.; Lee, A.M.; Lellouch, D.; Letts, J.; Levinson, L.; Liebisch, R.; List, B.; Littlewood, C.; Lloyd, A.W.; Lloyd, S.L.; Loebinger, F.K.; Long, G.D.; Losty, M.J.; Lu, J.; Ludwig, J.; Lui, D.; Macchiolo, A.; Macpherson, A.; Mader, W.; Mannelli, M.; Marcellini, S.; Markopoulos, C.; Martin, A.J.; Martin, J.P.; Martinez, G.; Mashimo, T.; Mattig, Peter; McDonald, W.John; McKenna, J.; Mckigney, E.A.; McMahon, T.J.; McPherson, R.A.; Meijers, F.; Menke, S.; Merritt, F.S.; Mes, H.; Meyer, J.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Mir, R.; Mohr, W.; Montanari, A.; Mori, T.; Nagai, K.; Nakamura, I.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oakham, F.G.; Odorici, F.; Ogren, H.O.; Oreglia, M.J.; Orito, S.; Palinkas, J.; Pasztor, G.; Pater, J.R.; Patrick, G.N.; Patt, J.; Perez-Ochoa, R.; Petzold, S.; Pfeifenschneider, P.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poffenberger, P.; Poli, B.; Polok, J.; Przybycien, M.; Rembser, C.; Rick, H.; Robertson, S.; Robins, S.A.; Rodning, N.; Roney, J.M.; Rosati, S.; Roscoe, K.; Rossi, A.M.; Rozen, Y.; Runge, K.; Runolfsson, O.; Rust, D.R.; Sachs, K.; Saeki, T.; Sahr, O.; Sang, W.M.; Sarkisian, E.K.G.; Sbarra, C.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schieck, J.; Schmitt, S.; Schoning, A.; Schroder, Matthias; Schumacher, M.; Schwick, C.; Scott, W.G.; Seuster, R.; Shears, T.G.; Shen, B.C.; Shepherd-Themistocleous, C.H.; Sherwood, P.; Siroli, G.P.; Sittler, A.; Skuja, A.; Smith, A.M.; Snow, G.A.; Sobie, R.; Soldner-Rembold, S.; Spagnolo, S.; Sproston, M.; Stahl, A.; Stephens, K.; Steuerer, J.; Stoll, K.; Strom, David M.; Strohmer, R.; Surrow, B.; Talbot, S.D.; Taras, P.; Tarem, S.; Teuscher, R.; Thiergen, M.; Thomas, J.; Thomson, M.A.; Torrence, E.; Towers, S.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turcot, A.S.; Turner-Watson, M.F.; Ueda, I.; Van Kooten, Rick J.; Vannerem, P.; Verzocchi, M.; Voss, H.; Wackerle, F.; Wagner, A.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wermes, N.; White, J.S.; Wilson, G.W.; Wilson, J.A.; Wyatt, T.R.; Yamashita, S.; Yekutieli, G.; Zacek, V.; Zer-Zion, D.

1999-01-01

A multidimensional study of local multiplicity fluctuations and multiparticle correlations of hadrons produced in Z decays is performed. The study is based on the data sample of more than 4 million events recorded with the OPAL detector at LEP. The fluctuations and correlations are analysed in terms of the normalized scaled factorial moments and cumulants up to the fifth order. The moments are observed to have intermittency-like behaviour, which is found to be more pronounced with increasing dimension. The large data sample allows for the first time a study of the factorial cumulants in e+e- annihilation. The analysis of the cumulants shows the existence of genuine multiparticle correlations with a strong intermittency rise up to higher orders. These correlations are found to be stronger in higher dimensions. The decomposition of the factorial moments into lower-order correlations that the dynamical fluctuations have important contributions from genuine many-particle correlations. The Monte Carlo models JETSE...

Estimating statistical uncertainty of Monte Carlo efficiency-gain in the context of a correlated sampling Monte Carlo code for brachytherapy treatment planning with non-normal dose distribution.

Science.gov (United States)

Mukhopadhyay, Nitai D; Sampson, Andrew J; Deniz, Daniel; Alm Carlsson, Gudrun; Williamson, Jeffrey; Malusek, Alexandr

2012-01-01

Correlated sampling Monte Carlo methods can shorten computing times in brachytherapy treatment planning. Monte Carlo efficiency is typically estimated via efficiency gain, defined as the reduction in computing time by correlated sampling relative to conventional Monte Carlo methods when equal statistical uncertainties have been achieved. The determination of the efficiency gain uncertainty arising from random effects, however, is not a straightforward task specially when the error distribution is non-normal. The purpose of this study is to evaluate the applicability of the F distribution and standardized uncertainty propagation methods (widely used in metrology to estimate uncertainty of physical measurements) for predicting confidence intervals about efficiency gain estimates derived from single Monte Carlo runs using fixed-collision correlated sampling in a simplified brachytherapy geometry. A bootstrap based algorithm was used to simulate the probability distribution of the efficiency gain estimates and the shortest 95% confidence interval was estimated from this distribution. It was found that the corresponding relative uncertainty was as large as 37% for this particular problem. The uncertainty propagation framework predicted confidence intervals reasonably well; however its main disadvantage was that uncertainties of input quantities had to be calculated in a separate run via a Monte Carlo method. The F distribution noticeably underestimated the confidence interval. These discrepancies were influenced by several photons with large statistical weights which made extremely large contributions to the scored absorbed dose difference. The mechanism of acquiring high statistical weights in the fixed-collision correlated sampling method was explained and a mitigation strategy was proposed. Copyright © 2011 Elsevier Ltd. All rights reserved.

Continuity, psychosocial correlates, and outcome of problematic substance use from adolescence to young adulthood in a community sample.

Science.gov (United States)

Steinhausen, Hans-Christoph; Eschmann, Susanne; Metzke, Christa Winkler

2007-10-11

The study of the continuity, psychosocial correlates, and prediction of problematic substance use (PSU) across time from adolescence to young adulthood. Substance use was studied in a cohort of N = 593 subjects who had been assessed at three times between adolescence and young adulthood within the Zurich Psychology and Psychopathology Study (ZAPPS). Based on the frequency of tobacco, alcohol, and cannabis consumption, groups with PSU were defined at each of the three measurement points in time and compared to the rest of the sample. Comparisons included questionnaire data regarding emotional and behavioural problems, life events, coping style, self-related cognitions, perceived parenting style, perceived school environment, and size and efficiency of the social network. The size of the groups with PSU increased continuously across time. The cross-sectional correlates of PSU were characterized by a similar pattern that included higher scores for externalizing behaviour, and both number and negative impact of life events across all three times. At time 1 and 2 subjects with PSU also experienced less favourable parenting styles and school environments. Longitudinally, PSU in young adulthood was predicted most strongly and persistently by previous risk status, externalizing problems and male gender. Problematic substance use is a major problem in youth. Its contributing pattern of associated and predictive psychosocial variables can be identified in the community.

Continuity, psychosocial correlates, and outcome of problematic substance use from adolescence to young adulthood in a community sample

Directory of Open Access Journals (Sweden)

Metzke Christa

2007-10-01

Full Text Available Abstract Background The study of the continuity, psychosocial correlates, and prediction of problematic substance use (PSU across time from adolescence to young adulthood. Methods Substance use was studied in a cohort of N = 593 subjects who had been assessed at three times between adolescence and young adulthood within the Zurich Psychology and Psychopathology Study (ZAPPS. Based on the frequency of tobacco, alcohol, and cannabis consumption, groups with PSU were defined at each of the three measurement points in time and compared to the rest of the sample. Comparisons included questionnaire data regarding emotional and behavioural problems, life events, coping style, self-related cognitions, perceived parenting style, perceived school environment, and size and efficiency of the social network. Results The size of the groups with PSU increased continuously across time. The cross-sectional correlates of PSU were characterized by a similar pattern that included higher scores for externalizing behaviour, and both number and negative impact of life events across all three times. At time 1 and 2 subjects with PSU also experienced less favourable parenting styles and school environments. Longitudinally, PSU in young adulthood was predicted most strongly and persistently by previous risk status, externalizing problems and male gender. Conclusion Problematic substance use is a major problem in youth. Its contributing pattern of associated and predictive psychosocial variables can be identified in the community.

Correlation between radon exhalation and radium content in granite samples used as construction material in Saudi Arabia

Energy Technology Data Exchange (ETDEWEB)

Al-Jarallah, M.I. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)]. E-mail: mibrahim@kfupm.edu.sa; Fazal-ur-Rehman [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Musazay, M.S. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Aksoy, A. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)

2005-11-15

Measurements of radon exhalation for a total of 205 selected samples of construction materials used in Saudi Arabia were carried out using an active radon gas analyzer with an emanation container. It was found that granite samples were the main source of radon exhalation. The radon exhalation rates per unit area from these granite samples varied from below the minimum detection limit up to 13.1Bqm{sup -2}h{sup -1} with an average of 1.5 +/-1.9(1{sigma})Bqm{sup -2}h{sup -1}. The radium contents of 27 granite samples were measured using an HPGe-based {gamma} spectroscopy setup. The {sup 226}Ra content of the granites varied from below the minimum detection limit up to 297Bqkg{sup -1}, with an average of 83+/-73(1{sigma})Bqkg{sup -1}. The linear correlation coefficient between exhaled radon and radium content was found to be 0.90.

First study of correlation between oleic acid content and SAD gene polymorphism in olive oil samples through statistical and bayesian modeling analyses.

Science.gov (United States)

Ben Ayed, Rayda; Ennouri, Karim; Ercişli, Sezai; Ben Hlima, Hajer; Hanana, Mohsen; Smaoui, Slim; Rebai, Ahmed; Moreau, Fabienne

2018-04-10

Virgin olive oil is appreciated for its particular aroma and taste and is recognized worldwide for its nutritional value and health benefits. The olive oil contains a vast range of healthy compounds such as monounsaturated free fatty acids, especially, oleic acid. The SAD.1 polymorphism localized in the Stearoyl-acyl carrier protein desaturase gene (SAD) was genotyped and showed that it is associated with the oleic acid composition of olive oil samples. However, the effect of polymorphisms in fatty acid-related genes on olive oil monounsaturated and saturated fatty acids distribution in the Tunisian olive oil varieties is not understood. Seventeen Tunisian olive-tree varieties were selected for fatty acid content analysis by gas chromatography. The association of SAD.1 genotypes with the fatty acids composition was studied by statistical and Bayesian modeling analyses. Fatty acid content analysis showed interestingly that some Tunisian virgin olive oil varieties could be classified as a functional food and nutraceuticals due to their particular richness in oleic acid. In fact, the TT-SAD.1 genotype was found to be associated with a higher proportion of mono-unsaturated fatty acids (MUFA), mainly oleic acid (C18:1) (r = - 0.79, p SAD.1 association with the oleic acid composition of olive oil was identified among the studied varieties. This correlation fluctuated between studied varieties, which might elucidate variability in lipidic composition among them and therefore reflecting genetic diversity through differences in gene expression and biochemical pathways. SAD locus would represent an excellent marker for identifying interesting amongst virgin olive oil lipidic composition.

Clinical and biochemical correlates of successful semen collection for cryopreservation from 12-18-year-old patients: a single-center study of 86 adolescents

DEFF Research Database (Denmark)

Hagenäs, Isabella; Jørgensen, Niels; Rechnitzer, Catherine

2010-01-01

Cryopreservation of semen should be offered to adults before gonadotoxic treatment. However, the experience with semen collection in adolescents is still limited. The objective of this study was to evaluate potential correlates of successful semen sampling in adolescents.......Cryopreservation of semen should be offered to adults before gonadotoxic treatment. However, the experience with semen collection in adolescents is still limited. The objective of this study was to evaluate potential correlates of successful semen sampling in adolescents....

Does duration of untreated psychosis bias study samples of first-episode psychosis?

DEFF Research Database (Denmark)

Friis, S; Melle, I; Larsen, T K

2004-01-01

OBJECTIVE: While findings are contradictory, many studies report that long Duration of Untreated Psychosis (DUP) correlates with poorer outcome in first episode psychosis. In an outcome study of first-episode psychosis, we compared the patients who refused to participate in a follow-along with th......OBJECTIVE: While findings are contradictory, many studies report that long Duration of Untreated Psychosis (DUP) correlates with poorer outcome in first episode psychosis. In an outcome study of first-episode psychosis, we compared the patients who refused to participate in a follow......-along with those who consented to estimate the importance of this factor in sample recruitment bias. Our questions were: (i) What is the percentage of refusers? (ii) Are there systematic differences between refusers and consenters on DUP and/or other admission variables? (iii) What is the risk of refusal...... for different values of DUP? METHOD: In an unselected group of consecutively admitted patients we compared follow-along refusers and consenters on the following admission variables: sex, age, diagnostic group, substance abuse, being in-patient, coming from an early detection site and DUP. We conducted...

The severity of ADHD and eating disorder symptoms: a correlational study

Directory of Open Access Journals (Sweden)

Stulz Niklaus

2013-02-01

Full Text Available Abstract Background Attention deficit/hyperactivity disorders (ADHD and eating disorders (ED share several clinical features. Research on the association between ADHD and ED is still quite sparse and findings are ambiguous. Methods Correlations between the severity of ADHD key features (Barratt Impulsiveness Scale, and Attention Deficit/Hyperactivity Disorder-Self-Rating questionnaire and the severity of specific ED symptoms (Structured Interview for Anorexia and Bulimia Nervosa were examined in 32 female patients diagnosed with ED. Results Most correlations between the severity of ADHD features and the severity of ED symptoms were low (r Conclusions The findings in this small sample suggest a weak link between the severity of ADHD key features and the severity of single ED symptoms in female patients with ED. The role of ADHD features for the development, maintenance, and treatment of EDs seems to be intricate and requires further study.

The MIXR sample or: how I learned to stop worrying and love multiwavelength catalogue cross-correlations

Science.gov (United States)

Mingo, Beatriz; Watson, Mike; Stewart, Gordon; Rosen, Simon; Blain, Andrew; Hardcastle, Martin; Mateos, Silvia; Carrera, Francisco; Ruiz, Angel; Pineau, Francois-Xavier

2016-08-01

We cross-match 3XMM, WISE and FIRST/NVSS to create the largest-to-date mid-IR, X-ray, and radio (MIXR) sample of galaxies and AGN. We use MIXR to triage sources and efficiently and accurately pre-classify them as star-forming galaxies or AGN, and to highlight bias and shortcomings in current AGN sample selection methods, paving the way for the next generation of instruments. Our results highlight key questions in AGN science, such as the need for a re-definition of the radio-loud/radio-quiet classification, and our observed lack of correlation between the kinetic (jet) and radiative (luminosity) output in AGN, which has dramatic potential consequences on our current understanding of AGN accretion, variability and feedback.

The role of sample preparation in interpretation of trace element concentration variability in moss bioindication studies

Science.gov (United States)

Migaszewski, Z.M.; Lamothe, P.J.; Crock, J.G.; Galuszka, A.; Dolegowska, S.

2011-01-01

Trace element concentrations in plant bioindicators are often determined to assess the quality of the environment. Instrumental methods used for trace element determination require digestion of samples. There are different methods of sample preparation for trace element analysis, and the selection of the best method should be fitted for the purpose of a study. Our hypothesis is that the method of sample preparation is important for interpretation of the results. Here we compare the results of 36 element determinations performed by ICP-MS on ashed and on acid-digested (HNO3, H2O2) samples of two moss species (Hylocomium splendens and Pleurozium schreberi) collected in Alaska and in south-central Poland. We found that dry ashing of the moss samples prior to analysis resulted in considerably lower detection limits of all the elements examined. We also show that this sample preparation technique facilitated the determination of interregional and interspecies differences in the chemistry of trace elements. Compared to the Polish mosses, the Alaskan mosses displayed more positive correlations of the major rock-forming elements with ash content, reflecting those elements' geogenic origin. Of the two moss species, P. schreberi from both Alaska and Poland was also highlighted by a larger number of positive element pair correlations. The cluster analysis suggests that the more uniform element distribution pattern of the Polish mosses primarily reflects regional air pollution sources. Our study has shown that the method of sample preparation is an important factor in statistical interpretation of the results of trace element determinations. ?? 2010 Springer-Verlag.

An open-chain imaginary-time path-integral sampling approach to the calculation of approximate symmetrized quantum time correlation functions

Science.gov (United States)

Cendagorta, Joseph R.; Bačić, Zlatko; Tuckerman, Mark E.

2018-03-01

We introduce a scheme for approximating quantum time correlation functions numerically within the Feynman path integral formulation. Starting with the symmetrized version of the correlation function expressed as a discretized path integral, we introduce a change of integration variables often used in the derivation of trajectory-based semiclassical methods. In particular, we transform to sum and difference variables between forward and backward complex-time propagation paths. Once the transformation is performed, the potential energy is expanded in powers of the difference variables, which allows us to perform the integrals over these variables analytically. The manner in which this procedure is carried out results in an open-chain path integral (in the remaining sum variables) with a modified potential that is evaluated using imaginary-time path-integral sampling rather than requiring the generation of a large ensemble of trajectories. Consequently, any number of path integral sampling schemes can be employed to compute the remaining path integral, including Monte Carlo, path-integral molecular dynamics, or enhanced path-integral molecular dynamics. We believe that this approach constitutes a different perspective in semiclassical-type approximations to quantum time correlation functions. Importantly, we argue that our approximation can be systematically improved within a cumulant expansion formalism. We test this approximation on a set of one-dimensional problems that are commonly used to benchmark approximate quantum dynamical schemes. We show that the method is at least as accurate as the popular ring-polymer molecular dynamics technique and linearized semiclassical initial value representation for correlation functions of linear operators in most of these examples and improves the accuracy of correlation functions of nonlinear operators.

An open-chain imaginary-time path-integral sampling approach to the calculation of approximate symmetrized quantum time correlation functions.

Science.gov (United States)

Cendagorta, Joseph R; Bačić, Zlatko; Tuckerman, Mark E

2018-03-14

We introduce a scheme for approximating quantum time correlation functions numerically within the Feynman path integral formulation. Starting with the symmetrized version of the correlation function expressed as a discretized path integral, we introduce a change of integration variables often used in the derivation of trajectory-based semiclassical methods. In particular, we transform to sum and difference variables between forward and backward complex-time propagation paths. Once the transformation is performed, the potential energy is expanded in powers of the difference variables, which allows us to perform the integrals over these variables analytically. The manner in which this procedure is carried out results in an open-chain path integral (in the remaining sum variables) with a modified potential that is evaluated using imaginary-time path-integral sampling rather than requiring the generation of a large ensemble of trajectories. Consequently, any number of path integral sampling schemes can be employed to compute the remaining path integral, including Monte Carlo, path-integral molecular dynamics, or enhanced path-integral molecular dynamics. We believe that this approach constitutes a different perspective in semiclassical-type approximations to quantum time correlation functions. Importantly, we argue that our approximation can be systematically improved within a cumulant expansion formalism. We test this approximation on a set of one-dimensional problems that are commonly used to benchmark approximate quantum dynamical schemes. We show that the method is at least as accurate as the popular ring-polymer molecular dynamics technique and linearized semiclassical initial value representation for correlation functions of linear operators in most of these examples and improves the accuracy of correlation functions of nonlinear operators.

CORRELATION STUDY AMONG WATER QUALITY PARAMETERS OF GROUNDWATER OF VALSAD DISTRICT OF SOUTH GUJARAT(INDIA

Directory of Open Access Journals (Sweden)

R. T. Vashi

2015-09-01

Full Text Available Groundwater samples were collected from five talukas of Valsad district for one year (from August 2008 to July 2009 and were analyzed for their physicochemical characteristics.  The present investigation is focused on  determination of parameters like pH, Colour, Electrical Conductivity (EC, Total Hardness (TH, Calcium (Ca, Magnesium (Mg, Total Alkalinity (TA, Total Dissolved Solids (TDS, Silica, Chloride, Sulphate, Fluoride, Sodium, Chemical Oxygen Demand (COD and metals like Copper (Cu and Manganese (Mn.  Correlation coefficients were determined to identify the highly correlated parameters and interrelated water quality parameters. Correlation matrix of Valsad district suggests that EC of groundwater is found to be significantly correlated with eight out of seventeen water quality parameters studied.  It may be suggested that the quality of Valsad district can be checked very effectively by controlling EC of water.

Study of Zn/Cu ratio and oligoelements in serum samples for cancer diagnosis

International Nuclear Information System (INIS)

Lue-Meru, M. P.; Jimenez, E.; Hernandez, E.; Rojas, A.; Greaves, E.

2000-01-01

The aim of this work was to study methods for cancer diagnosis based on trace element determination in serum blood samples. TXRF technique was selected for the analysis, due to its simultaneous and multi-elemental character, the very small amount of sample required and the high sensitivity. For the study, blood samples were collected from normal individuals (Blood donors and students), classified by age and sex in order to obtain reference normal values for the elements Zn, Cu, Fe, Mn, Se, and additionally, Ca and K. Samples from cancer patients before treatment and under treatment were collected at the oncological Service (BADAN-Lara), and were also classified by age and sex. The TXRF procedure used was developed in a previous work and involves the direct analysis and the use of Compton peak as Internal Standard. All the samples were analyzed by the routine clinical test (blood chemistry). Elemental concentrations and clinical data were processed with the statistical package Minitab-Windows, in order to establish the respective correlation. Concerning to elemental concentrations, significant differences were found in Zn/Cu ratio between normal individuals group and the cancer patients group. (author)

Vibronic Boson Sampling: Generalized Gaussian Boson Sampling for Molecular Vibronic Spectra at Finite Temperature.

Science.gov (United States)

Huh, Joonsuk; Yung, Man-Hong

2017-08-07

Molecular vibroic spectroscopy, where the transitions involve non-trivial Bosonic correlation due to the Duschinsky Rotation, is strongly believed to be in a similar complexity class as Boson Sampling. At finite temperature, the problem is represented as a Boson Sampling experiment with correlated Gaussian input states. This molecular problem with temperature effect is intimately related to the various versions of Boson Sampling sharing the similar computational complexity. Here we provide a full description to this relation in the context of Gaussian Boson Sampling. We find a hierarchical structure, which illustrates the relationship among various Boson Sampling schemes. Specifically, we show that every instance of Gaussian Boson Sampling with an initial correlation can be simulated by an instance of Gaussian Boson Sampling without initial correlation, with only a polynomial overhead. Since every Gaussian state is associated with a thermal state, our result implies that every sampling problem in molecular vibronic transitions, at any temperature, can be simulated by Gaussian Boson Sampling associated with a product of vacuum modes. We refer such a generalized Gaussian Boson Sampling motivated by the molecular sampling problem as Vibronic Boson Sampling.

Correlation of Heavy Element in Sea Water and Sediment Samples from Peninsula of Muria

International Nuclear Information System (INIS)

Rosidi; Sukirno

2007-01-01

The analysis of heavy metals in marine environmental samples peninsula of Muria in the year 2004 has been carried out by using neutron activation analysis (NAA) method. The objective of this analysis is to know the distribution of heavy metals in the sea water and sediment, which accommodate the recent environmental data in supporting the license of site for the nuclear power plants (NPP). The result of the analysis show that there were only 5 observed elements found in sea water and sediment were Cd, Co, Cr, Sb and Sc. All of heavy metals from sea water (0.002 mg/l) are obviously lower than the threshold value established by environmental minister Act; Kep LH No 51/2004. From the observed data to use software of SPSS version 10, application of the Pearson correlation (r) shows that between Co with Sc was indicator show a highly positive significant correlation (r=0.928), between Cr with Sc was sufficiently positive high (r=0.756), between Cr with Cd was precisely (r=0.611) while Co with Sb shows the significantly low (r=0.429). (author)

Are most samples of animals systematically biased? Consistent individual trait differences bias samples despite random sampling.

Science.gov (United States)

Biro, Peter A

2013-02-01

Sampling animals from the wild for study is something nearly every biologist has done, but despite our best efforts to obtain random samples of animals, 'hidden' trait biases may still exist. For example, consistent behavioral traits can affect trappability/catchability, independent of obvious factors such as size and gender, and these traits are often correlated with other repeatable physiological and/or life history traits. If so, systematic sampling bias may exist for any of these traits. The extent to which this is a problem, of course, depends on the magnitude of bias, which is presently unknown because the underlying trait distributions in populations are usually unknown, or unknowable. Indeed, our present knowledge about sampling bias comes from samples (not complete population censuses), which can possess bias to begin with. I had the unique opportunity to create naturalized populations of fish by seeding each of four small fishless lakes with equal densities of slow-, intermediate-, and fast-growing fish. Using sampling methods that are not size-selective, I observed that fast-growing fish were up to two-times more likely to be sampled than slower-growing fish. This indicates substantial and systematic bias with respect to an important life history trait (growth rate). If correlations between behavioral, physiological and life-history traits are as widespread as the literature suggests, then many animal samples may be systematically biased with respect to these traits (e.g., when collecting animals for laboratory use), and affect our inferences about population structure and abundance. I conclude with a discussion on ways to minimize sampling bias for particular physiological/behavioral/life-history types within animal populations.

Religiousness and preoperative anxiety: a correlational study.

Science.gov (United States)

Kalkhoran, Masoomeh Aghamohammadi; Karimollahi, Mansoureh

2007-06-29

Major life changes are among factors that cause anxiety, and one of these changes is surgery. Emotional reactions to surgery have specific effects on the intensity and velocity as well as the process of physical disease. In addition, they can cause delay in patients recovery. This study is aimed at determining the relationship between religious beliefs and preoperative anxiety. This survey is a correlational study to assess the relationship between religious beliefs and preoperative anxiety of patients undergoing abdominal, orthopaedic, and gynaecologic surgery in educational hospitals. We used the convenience sampling method. The data collection instruments included a questionnaire containing the Spielberger State-Trait Anxiety Inventory (STAI), and another questionnaire formulated by the researcher with queries on religious beliefs and demographic characteristics as well as disease-related information. Analysis of the data was carried out with SPSS software using descriptive and inferential statistics. Results were arranged in three tables. The findings showed that almost all the subjects had high level of religiosity and moderate level of anxiety. In addition, there was an inverse relationship between religiosity and intensity of anxiety, though this was not statistically significant. The results of this study can be used as evidence for presenting religious counselling and spiritual interventions for individuals undergoing stress. Finally, based on the results of this study, the researcher suggested some recommendations for applying results and conducting further research.

Sample Set (SE): SE47 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available SE47 Metabolomic correlation-network modules in Arabidopsis based on a graph-cluste...as a system. Typical metabolomics data show a few but significant correlations among metabolite levels when ...itions. Although several studies have assessed topologies in metabolomic correlation networks, it remains un... (mto1), and transparent testa4 (tt4) to compare systematically the metabolomic correlation...s in samples of roots and aerial parts. We then applied graph clustering to the constructed correlation

Sample size determination for equivalence assessment with multiple endpoints.

Science.gov (United States)

Sun, Anna; Dong, Xiaoyu; Tsong, Yi

2014-01-01

Equivalence assessment between a reference and test treatment is often conducted by two one-sided tests (TOST). The corresponding power function and sample size determination can be derived from a joint distribution of the sample mean and sample variance. When an equivalence trial is designed with multiple endpoints, it often involves several sets of two one-sided tests. A naive approach for sample size determination in this case would select the largest sample size required for each endpoint. However, such a method ignores the correlation among endpoints. With the objective to reject all endpoints and when the endpoints are uncorrelated, the power function is the production of all power functions for individual endpoints. With correlated endpoints, the sample size and power should be adjusted for such a correlation. In this article, we propose the exact power function for the equivalence test with multiple endpoints adjusted for correlation under both crossover and parallel designs. We further discuss the differences in sample size for the naive method without and with correlation adjusted methods and illustrate with an in vivo bioequivalence crossover study with area under the curve (AUC) and maximum concentration (Cmax) as the two endpoints.

Influence of the operating parameters and of the sample introduction system on time correlation of line intensities using an axially viewed CCD-based ICP-AES system

Energy Technology Data Exchange (ETDEWEB)

Grotti, Marco, E-mail: grotti@chimica.unige.i [Dipartimento di Chimica e Chimica Industriale, Via Dodecaneso 31, 16146 Genova (Italy); Todoli, Jose Luis [Departamento de Quimica Analitica, Nutricion y Bromatologia, Universidad de Alicante, 03080, Alicante (Spain); Mermet, Jean Michel [Spectroscopy Forever, 01390 Tramoyes (France)

2010-02-15

The influence of the acquisition and operating parameters on time correlation between emission line intensities was investigated using axially viewed inductively coupled plasma-multichannel-based emission spectrometry and various sample introduction systems. It was found that to obtain flicker-noise limited signals, necessary to compensate for time-correlated signal fluctuations by internal standardization, the flicker-noise magnitude of the sample introduction system, the integration time and the emission line intensity had to be considered. The highest correlation between lines was observed for ultrasonic nebulization with desolvatation, the noisiest system among those considered, for which the contribution of the uncorrelated shot-noise was negligible. In contrast, for sample introduction systems characterized by lower flicker-noise levels, shot-noise led to high, non-correlated RSD values, making the internal standard method to be much less efficient. To minimize shot-noise, time correlation was improved by increasing the emission line intensities and the integration time. Improvement in repeatability did not depend only on time correlation, but also on the ratio between the relative standard deviations of the analytical and reference lines. The best signal compensation was obtained when RSD values of the reference and analytical lines were similar, which is usually obtained when the system is flicker-noise limited, while departure from similarity can lead to a degradation of repeatability when using the internal standard method. Moreover, the use of so-called robust plasma conditions, i.e. a high power (1500 W) along with a low carrier gas flow rate (0.8 L/min) improved also the compensation. Finally, high correlation and consequent improvement in repeatability by internal standardization was observed also in the presence of complex matrices (sediment and soil samples), although a matrix-induced degradation of the correlation between lines was generally

A study on the correlation between the dewetting temperature of Ag film and SERS intensity.

Science.gov (United States)

Quan, Jiamin; Zhang, Jie; Qi, Xueqiang; Li, Junying; Wang, Ning; Zhu, Yong

2017-11-07

The thermally dewetted metal nano-islands have been actively investigated as cost-effective SERS-active substrates with a large area, good reproducibility and repeatability via simple fabrication process. However, the correlation between the dewetting temperature of metal film and SERS intensity hasn't been systematically studied. In this work, taking Ag nano-islands (AgNIs) as an example, we reported a strategy to investigate the correlation between the dewetting temperature of metal film and SERS intensity. We described the morphology evolution of AgNIs on the SiO 2 planar substrate in different temperatures and got the quantitative information in surface-limited diffusion process (SLDP) as a function of annealing temperature via classical mean-field nucleation theory. Those functions were further used in the simulation of electromagnetic field to obtain the correlation between the dewetting temperature of Ag film and theoretical analysis. In addition, Raman mapping was done on samples annealed at different temperatures, with R6G as an analyte, to accomplish the analysis of the correlation between the dewetting temperature of Ag film and SERS intensity, which is consistent with the theoretical analysis. For SLDP, we used the morphological characterization of five samples prepared by different annealing temperatures to successfully illustrate the change in SERS intensity with the temperature fluctuation, obtaining a small deviation between the experimental results and theoretic prediction.

A generalized Levene's scale test for variance heterogeneity in the presence of sample correlation and group uncertainty.

Science.gov (United States)

Soave, David; Sun, Lei

2017-09-01

We generalize Levene's test for variance (scale) heterogeneity between k groups for more complex data, when there are sample correlation and group membership uncertainty. Following a two-stage regression framework, we show that least absolute deviation regression must be used in the stage 1 analysis to ensure a correct asymptotic χk-12/(k-1) distribution of the generalized scale (gS) test statistic. We then show that the proposed gS test is independent of the generalized location test, under the joint null hypothesis of no mean and no variance heterogeneity. Consequently, we generalize the recently proposed joint location-scale (gJLS) test, valuable in settings where there is an interaction effect but one interacting variable is not available. We evaluate the proposed method via an extensive simulation study and two genetic association application studies. © 2017 The Authors Biometrics published by Wiley Periodicals, Inc. on behalf of International Biometric Society.

Planimetric correlation between the submandibular glands and the pancreas: a postmortem ductographic study.

Science.gov (United States)

Stimec, Bojan V; Rakocevic, Zoran; Ignjatovic, Dejan; Fasel, Jean H D

2018-01-01

The salivary glands and pancreas have comparable anatomic and antigenic properties and can share common pathogenetic mechanisms involving toxic or autoimmune processes. The aim of this study is to assess the correlation in size between the normal submandibular glands and the pancreas. The study was based on human autopsy specimens of the pancreas, neck and oral base from 22 adults, both sexes (mean age, 57.9 years). The pancreatic and submandibular ducts were injected with a contrast medium, and the area of the salivary and pancreatic glandular ductograms was measured with the aid of software for quantification of visual information. Samples of tissue from the salivary glands and the pancreas were studied by means of light microscopy. A high correlation was found between the planimetric size of the pancreas and the submandibular glands (correlation coefficient 0.497 and 0.699 for the right and the left gland, respectively). This ratio was close to 5:1. There were no significant differences in size for the left vs. right submandibular gland (p = 0.39). The ductograms were significantly larger in size in males than in females (p pancreas, a result that is expected to have possible clinical implications in the long-term follow-up of patients with chronic pancreatitis.

Correlations Between Life-Detection Techniques and Implications for Sampling Site Selection in Planetary Analog Missions

Science.gov (United States)

Gentry, Diana M.; Amador, Elena S.; Cable, Morgan L.; Chaudry, Nosheen; Cullen, Thomas; Jacobsen, Malene B.; Murukesan, Gayathri; Schwieterman, Edward W.; Stevens, Adam H.; Stockton, Amanda; Tan, George; Yin, Chang; Cullen, David C.; Geppert, Wolf

2017-10-01

We conducted an analog sampling expedition under simulated mission constraints to areas dominated by basaltic tephra of the Eldfell and Fimmvörðuháls lava fields (Iceland). Sites were selected to be "homogeneous" at a coarse remote sensing resolution (10-100 m) in apparent color, morphology, moisture, and grain size, with best-effort realism in numbers of locations and replicates. Three different biomarker assays (counting of nucleic-acid-stained cells via fluorescent microscopy, a luciferin/luciferase assay for adenosine triphosphate, and quantitative polymerase chain reaction (qPCR) to detect DNA associated with bacteria, archaea, and fungi) were characterized at four nested spatial scales (1 m, 10 m, 100 m, and >1 km) by using five common metrics for sample site representativeness (sample mean variance, group F tests, pairwise t tests, and the distribution-free rank sum H and u tests). Correlations between all assays were characterized with Spearman's rank test. The bioluminescence assay showed the most variance across the sites, followed by qPCR for bacterial and archaeal DNA; these results could not be considered representative at the finest resolution tested (1 m). Cell concentration and fungal DNA also had significant local variation, but they were homogeneous over scales of >1 km. These results show that the selection of life detection assays and the number, distribution, and location of sampling sites in a low biomass environment with limited a priori characterization can yield both contrasting and complementary results, and that their interdependence must be given due consideration to maximize science return in future biomarker sampling expeditions.

Electron spin echo studies of the internal motion of radicals in crystals: Phase memory vs correlation time

International Nuclear Information System (INIS)

Kispert, L.D.; Bowman, M.K.; Norris, J.R.; Brown, M.S.

1982-01-01

An electron spin echo (ESE) study of the internal motion of the CH 2 protons in irradiated zinc acetate dihydrate crystals shows that quantitative measurements of the motional correlation time can be obtained quite directly from pulsed measurements. In the slow motional limit, the motional correlation time is equal to the phase memory time determined by ESE. In the fast motional limit, the motional correlation time is proportional to the no motion spectral second moment divided by the ESE phase memory time. ESE offers a convenient method of studying motion, electron transfer, conductivity, etc. in a variety of systems too complicated for study by ordinary EPR. New systems for study by ESE include biological samples, organic polymers, liquid solutions of radicals with unresolved hyperfine, etc. When motion modulates large anisotropic hyperfine couplings, ESE measurements of the phase memory time are sensitive to modulation of pseudosecular hyperfine interactions

A Study of Parton Fragmentation in Hadronic $Z^{0}$ Decays Using $\\Lambda \\overline\\Lambda$ Correlations

CERN Document Server

Abbiendi, G.; Alexander, G.; Allison, John; Altekamp, N.; Anderson, K.J.; Anderson, S.; Arcelli, S.; Asai, S.; Ashby, S.F.; Axen, D.; Azuelos, G.; Ball, A.H.; Barberio, E.; Barlow, Roger J.; Bartoldus, R.; Batley, J.R.; Baumann, S.; Bechtluft, J.; Behnke, T.; Bell, Kenneth Watson; Bella, G.; Bellerive, A.; Bentvelsen, S.; Bethke, S.; Betts, S.; Biebel, O.; Biguzzi, A.; Bird, S.D.; Blobel, V.; Bloodworth, I.J.; Bobinski, M.; Bock, P.; Bohme, J.; Bonacorsi, D.; Boutemeur, M.; Braibant, S.; Bright-Thomas, P.; Brigliadori, L.; Brown, Robert M.; Burckhart, H.J.; Burgard, C.; Burgin, R.; Capiluppi, P.; Carnegie, R.K.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, David G.; Chrisman, D.; Ciocca, C.; Clarke, P.E.L.; Clay, E.; Cohen, I.; Conboy, J.E.; Cooke, O.C.; Couyoumtzelis, C.; Coxe, R.L.; Cuffiani, M.; Dado, S.; Dallavalle, G.Marco; Davis, R.; De Jong, S.; del Pozo, L.A.; De Roeck, A.; Desch, K.; Dienes, B.; Dixit, M.S.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Eatough, D.; Estabrooks, P.G.; Etzion, E.; Evans, H.G.; Fabbri, F.; Fanti, M.; Faust, A.A.; Fiedler, F.; Fierro, M.; Fleck, I.; Folman, R.; Furtjes, A.; Futyan, D.I.; Gagnon, P.; Gary, J.W.; Gascon, J.; Gascon-Shotkin, S.M.; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Gibson, V.; Gibson, W.R.; Gingrich, D.M.; Glenzinski, D.; Goldberg, J.; Gorn, W.; Grandi, C.; Gross, E.; Grunhaus, J.; Gruwe, M.; Hanson, G.G.; Hansroul, M.; Hapke, M.; Harder, K.; Hargrove, C.K.; Hartmann, C.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Herndon, M.; Herten, G.; Heuer, R.D.; Hildreth, M.D.; Hill, J.C.; Hillier, S.J.; Hobson, P.R.; Hocker, James Andrew; Homer, R.J.; Honma, A.K.; Horvath, D.; Hossain, K.R.; Howard, R.; Huntemeyer, P.; Igo-Kemenes, P.; Imrie, D.C.; Ishii, K.; Jacob, F.R.; Jawahery, A.; Jeremie, H.; Jimack, M.; Jones, C.R.; Jovanovic, P.; Junk, T.R.; Karlen, D.; Kartvelishvili, V.; Kawagoe, K.; Kawamoto, T.; Kayal, P.I.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Klier, A.; Kluth, S.; Kobayashi, T.; Kobel, M.; Koetke, D.S.; Kokott, T.P.; Kolrep, M.; Komamiya, S.; Kowalewski, Robert V.; Kress, T.; Krieger, P.; von Krogh, J.; Kuhl, T.; Kyberd, P.; Lafferty, G.D.; Lanske, D.; Lauber, J.; Lautenschlager, S.R.; Lawson, I.; Layter, J.G.; Lazic, D.; Lee, A.M.; Lellouch, D.; Letts, J.; Levinson, L.; Liebisch, R.; List, B.; Littlewood, C.; Lloyd, A.W.; Lloyd, S.L.; Loebinger, F.K.; Long, G.D.; Losty, M.J.; Ludwig, J.; Lui, D.; Macchiolo, A.; Macpherson, A.; Mader, W.; Mannelli, M.; Marcellini, S.; Markopoulos, C.; Martin, A.J.; Martin, J.P.; Martinez, G.; Mashimo, T.; Mattig, Peter; McDonald, W.John; McKenna, J.; Mckigney, E.A.; McMahon, T.J.; McPherson, R.A.; Meijers, F.; Menke, S.; Merritt, F.S.; Mes, H.; Meyer, J.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Mir, R.; Mohr, W.; Montanari, A.; Mori, T.; Nagai, K.; Nakamura, I.; Neal, H.A.; Nellen, B.; Nisius, R.; O'Neale, S.W.; Oakham, F.G.; Odorici, F.; Ogren, H.O.; Oreglia, M.J.; Orito, S.; Palinkas, J.; Pasztor, G.; Pater, J.R.; Patrick, G.N.; Patt, J.; Perez-Ochoa, R.; Petzold, S.; Pfeifenschneider, P.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poffenberger, P.; Polok, J.; Przybycien, M.; Rembser, C.; Rick, H.; Robertson, S.; Robins, S.A.; Rodning, N.; Roney, J.M.; Roscoe, K.; Rossi, A.M.; Rozen, Y.; Runge, K.; Runolfsson, O.; Rust, D.R.; Sachs, K.; Saeki, T.; Sahr, O.; Sang, W.M.; Sarkisian, E.K.G.; Sbarra, C.; Schaile, A.D.; Schaile, O.; Scharf, F.; Scharff-Hansen, P.; Schieck, J.; Schmitt, B.; Schmitt, S.; Schmitz, R.E.; Schoning, A.; Schroder, Matthias; Schumacher, M.; Schwick, C.; Scott, W.G.; Seuster, R.; Shears, T.G.; Shen, B.C.; Shepherd-Themistocleous, C.H.; Sherwood, P.; Siroli, G.P.; Sittler, A.; Skuja, A.; Smith, A.M.; Snow, G.A.; Sobie, R.; Soldner-Rembold, S.; Sproston, M.; Stahl, A.; Stephens, K.; Steuerer, J.; Stoll, K.; Strom, David M.; Strohmer, R.; Surrow, B.; Talbot, S.D.; Tanaka, S.; Taras, P.; Tarem, S.; Teuscher, R.; Thiergen, M.; Thomson, M.A.; von Torne, E.; Torrence, E.; Towers, S.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turcot, A.S.; Turner-Watson, M.F.; Van Kooten, Rick J.; Vannerem, P.; Verzocchi, M.; Voss, H.; Wackerle, F.; Wagner, A.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wermes, N.; White, J.S.; Wilson, G.W.; Wilson, J.A.; Wyatt, T.R.; Yamashita, S.; Yekutieli, G.; Zacek, V.; Zer-Zion, D.

2000-01-01

The correlated production of Lambda and Lambdabar baryons has been studied using 4.3 million multihadronic Zo decays recorded with the OPAL detector at LEP. Di-lambda pairs were investigated in the full data sample and for the first time also in 2-jet and 3-jet events selected with the k_t algorithm. The distributions of rapidity differences from correlated Lambda-Lambdabar pairs exhibit short-range, local correlations and prove to be a sensitive tool to test models, particularly for 2-jet events. The JETSET model describes the data best but some extra parameter tuning is needed to improve agreement with the experimental results in the rates and the rapidity spectra simultaneously. The recently developed modification of JETSET, the MOdified Popcorn Scenarium (MOPS), and also HERWIG do not give satisfactory results. This study of di-lambda production in 2- and 3-jet events supports the short-range compensation of quantum numbers.

An improved method for bivariate meta-analysis when within-study correlations are unknown.

Science.gov (United States)

Hong, Chuan; D Riley, Richard; Chen, Yong

2018-03-01

Multivariate meta-analysis, which jointly analyzes multiple and possibly correlated outcomes in a single analysis, is becoming increasingly popular in recent years. An attractive feature of the multivariate meta-analysis is its ability to account for the dependence between multiple estimates from the same study. However, standard inference procedures for multivariate meta-analysis require the knowledge of within-study correlations, which are usually unavailable. This limits standard inference approaches in practice. Riley et al proposed a working model and an overall synthesis correlation parameter to account for the marginal correlation between outcomes, where the only data needed are those required for a separate univariate random-effects meta-analysis. As within-study correlations are not required, the Riley method is applicable to a wide variety of evidence synthesis situations. However, the standard variance estimator of the Riley method is not entirely correct under many important settings. As a consequence, the coverage of a function of pooled estimates may not reach the nominal level even when the number of studies in the multivariate meta-analysis is large. In this paper, we improve the Riley method by proposing a robust variance estimator, which is asymptotically correct even when the model is misspecified (ie, when the likelihood function is incorrect). Simulation studies of a bivariate meta-analysis, in a variety of settings, show a function of pooled estimates has improved performance when using the proposed robust variance estimator. In terms of individual pooled estimates themselves, the standard variance estimator and robust variance estimator give similar results to the original method, with appropriate coverage. The proposed robust variance estimator performs well when the number of studies is relatively large. Therefore, we recommend the use of the robust method for meta-analyses with a relatively large number of studies (eg, m≥50). When the

Vaginismus and its correlates in an Iranian clinical sample.

Science.gov (United States)

Farnam, F; Janghorbani, M; Merghati-Khoei, E; Raisi, F

2014-01-01

Although vaginismus is a relatively common female sexual dysfunction in Iran, there are scant studies reporting on its clinical and social features. The aim of the present study was to compare the social and clinical characteristics of women with vaginismus with those of healthy women. The study comprises 22 patients with vaginismus and 22 healthy controls who presented to the health clinics of Tehran University of Medical Sciences, Iran. We used three assessment tools: interview, a (34-item) questionnaire for demographic and clinical characteristics of vaginismus and a 13-item questionnaire of Female Sexual Distress Scale-Revised (FSDS-R) for sexual distress. The majority (73%) of women with vaginismus had primary vaginismus (unconsummated marriage). These women demonstrated significant higher phobia than healthy women, including fear of genital pain and penetration, fear of bleeding during intercourse, height phobia, aversion to looking or touching the genitalia, fear of vaginal disproportion and also disgust of semen. Compared with the healthy women, these women displayed a significantly higher sexual distress score, defecation or urination problems, general anxiety, higher education levels and lower self-esteem. Our findings suggest that there is a strong correlation between vaginismus, phobia and anxiety.

Correlates of Unwanted Births in Bangladesh: A Study through Path Analysis.

Science.gov (United States)

Roy, Tapan Kumar; Singh, Brijesh P

2016-01-01

Unwanted birth is an important public health concern due to its negative association with adverse outcomes of mothers and children as well as socioeconomic development of a country. Although a number of studies have been investigated the determinants of unwanted births through logistic regression analysis, an extensive assessment using path model is lacking. In the current study, we applied path analysis to know the important covariates for unwanted births in Bangladesh. The study used data extracted from Bangladesh Demographic and Health Survey (BDHS) 2011. It considered sub-sample consisted of 7,972 women who had given most recent births five years preceding the date of interview or who were currently pregnant at survey time. Correlation analysis was used to find out the significant association with unwanted births. This study provided the factors affecting unwanted births in Bangladesh. The path model was used to determine the direct, indirect and total effects of socio-demographic factors on unwanted births. The result exhibited that more than one-tenth of the recent births were unwanted in Bangladesh. The differentials of unwanted births were women's age, education, age at marriage, religion, socioeconomic status, exposure of mass-media and use of family planning. In correlation analysis, it showed that unwanted births were positively correlated with women age and place of residence and these relationships were significant. On the contrary, unwanted births were inversely significantly correlated with education and social status. The total effects of endogenous variables such as women age, place of residence and use of family planning methods had favorable effect on unwanted births. Policymakers and program planners need to design programs and services carefully to reduce unwanted births in Bangladesh, especially, service should focus on helping those groups of women who were identified in the analysis as being at increased risks of unwanted births- older women

Correlates of Unwanted Births in Bangladesh: A Study through Path Analysis.

Directory of Open Access Journals (Sweden)

Tapan Kumar Roy

Full Text Available Unwanted birth is an important public health concern due to its negative association with adverse outcomes of mothers and children as well as socioeconomic development of a country. Although a number of studies have been investigated the determinants of unwanted births through logistic regression analysis, an extensive assessment using path model is lacking. In the current study, we applied path analysis to know the important covariates for unwanted births in Bangladesh.The study used data extracted from Bangladesh Demographic and Health Survey (BDHS 2011. It considered sub-sample consisted of 7,972 women who had given most recent births five years preceding the date of interview or who were currently pregnant at survey time. Correlation analysis was used to find out the significant association with unwanted births. This study provided the factors affecting unwanted births in Bangladesh. The path model was used to determine the direct, indirect and total effects of socio-demographic factors on unwanted births.The result exhibited that more than one-tenth of the recent births were unwanted in Bangladesh. The differentials of unwanted births were women's age, education, age at marriage, religion, socioeconomic status, exposure of mass-media and use of family planning. In correlation analysis, it showed that unwanted births were positively correlated with women age and place of residence and these relationships were significant. On the contrary, unwanted births were inversely significantly correlated with education and social status. The total effects of endogenous variables such as women age, place of residence and use of family planning methods had favorable effect on unwanted births.Policymakers and program planners need to design programs and services carefully to reduce unwanted births in Bangladesh, especially, service should focus on helping those groups of women who were identified in the analysis as being at increased risks of unwanted

Dissociation, personality, suggestibility, alexithymia, and problems with emotional regulation: A correlational study

Directory of Open Access Journals (Sweden)

Ángeles Serrano

2016-12-01

Full Text Available The present paper explores the relationship between psychological and somatic dissociation and different personality and emotional variables, including suggestibility, alexithymia, and emotional regulation and dysregulation. The results with a sample of 355 partipants of a normal population reveal that there is a positive relationship between both types of dissociation, suggestibility and emotional dysregulation. Likewise, there were different patterns of personality associated both to psychological and somatic dissociation. Correlations found in this study put forward the importance to take into account both types of dissociactive symptoms, psychological and somatic ones.

Cluster Sampling Bias in Government-Sponsored Evaluations: A Correlational Study of Employment and Welfare Pilots in England.

Science.gov (United States)

Vaganay, Arnaud

2016-01-01

For pilot or experimental employment programme results to apply beyond their test bed, researchers must select 'clusters' (i.e. the job centres delivering the new intervention) that are reasonably representative of the whole territory. More specifically, this requirement must account for conditions that could artificially inflate the effect of a programme, such as the fluidity of the local labour market or the performance of the local job centre. Failure to achieve representativeness results in Cluster Sampling Bias (CSB). This paper makes three contributions to the literature. Theoretically, it approaches the notion of CSB as a human behaviour. It offers a comprehensive theory, whereby researchers with limited resources and conflicting priorities tend to oversample 'effect-enhancing' clusters when piloting a new intervention. Methodologically, it advocates for a 'narrow and deep' scope, as opposed to the 'wide and shallow' scope, which has prevailed so far. The PILOT-2 dataset was developed to test this idea. Empirically, it provides evidence on the prevalence of CSB. In conditions similar to the PILOT-2 case study, investigators (1) do not sample clusters with a view to maximise generalisability; (2) do not oversample 'effect-enhancing' clusters; (3) consistently oversample some clusters, including those with higher-than-average client caseloads; and (4) report their sampling decisions in an inconsistent and generally poor manner. In conclusion, although CSB is prevalent, it is still unclear whether it is intentional and meant to mislead stakeholders about the expected effect of the intervention or due to higher-level constraints or other considerations.

Determination of alpha-dose rates and chronostratigraphical study of travertine samples

International Nuclear Information System (INIS)

Oufni, L.; University Moulay Ismail, Errachidia; Misdaq, M.A.; Boudad, L.; Kabiri, L.

2001-01-01

Uranium and thorium contents in different layers of stratigraphical sedimentary deposits have been evaluated by using LR-115 type II and CR-39 solid state nuclear track detectors (SSNTD). A method has been developed for determining the alpha-dose rates of the sedimentary travertine samples. Using the U/Th dating method, we succeeded in age dating carbonated level sampled in the sedimentary deposits. Correlation between the stratigraphy, alpha-dose rates and age has been investigated. (author)

Gambling Type, Substance Abuse, Health and Psychosocial Correlates of Male and Female Problem Gamblers in a Nationally Representative French Sample.

Science.gov (United States)

Bonnaire, C; Kovess-Masfety, V; Guignard, R; Richard, J B; du Roscoät, E; Beck, F

2017-06-01

Many studies carried out on treatment-seeking problem gamblers (PG) have reported high levels of comorbid substance use disorders, and mental and physical health problems. Nevertheless, general population studies are still sparse, most of them have been carried out in the United States or Canada, and gender differences have not always been considered. Thus, the aim of this study was to describe the type of games, and psychological and physical correlates in male and female PG in a nationally representative French sample. The total sample studied involved 25,647 subjects aged 15-85 years, including 333 PG and 25,314 non-problem gamblers (NPG). Data were extracted from a large survey of a representative sample of the French general population. They were evaluated for sociodemographic variables, gambling behavior, type of gambling activity, substance use, psychological distress, body mass index, chronic disease, and lack of sleep. Overall, there were significant differences between PG and NPG in gender, age, education, employment and marital status, substance use disorders (alcohol, tobacco, cannabis, cocaine and heroin), psychological distress, obesity, lack of sleep and type of gambling activity. Although male and female PG had different profiles, the gambling type, especially strategic games, appeared as an important variable in the relationship between gender and problem gambling. This research underlines the importance of considering gender differences and gambling type in the study of gambling disorders. Identifying specific factors in the relationship between gender, gambling type and gambling problems may help improve clinical interventions and health promotion strategies.

Linear models for airborne-laser-scanning-based operational forest inventory with small field sample size and highly correlated LiDAR data

Science.gov (United States)

Junttila, Virpi; Kauranne, Tuomo; Finley, Andrew O.; Bradford, John B.

2015-01-01

Modern operational forest inventory often uses remotely sensed data that cover the whole inventory area to produce spatially explicit estimates of forest properties through statistical models. The data obtained by airborne light detection and ranging (LiDAR) correlate well with many forest inventory variables, such as the tree height, the timber volume, and the biomass. To construct an accurate model over thousands of hectares, LiDAR data must be supplemented with several hundred field sample measurements of forest inventory variables. This can be costly and time consuming. Different LiDAR-data-based and spatial-data-based sampling designs can reduce the number of field sample plots needed. However, problems arising from the features of the LiDAR data, such as a large number of predictors compared with the sample size (overfitting) or a strong correlation among predictors (multicollinearity), may decrease the accuracy and precision of the estimates and predictions. To overcome these problems, a Bayesian linear model with the singular value decomposition of predictors, combined with regularization, is proposed. The model performance in predicting different forest inventory variables is verified in ten inventory areas from two continents, where the number of field sample plots is reduced using different sampling designs. The results show that, with an appropriate field plot selection strategy and the proposed linear model, the total relative error of the predicted forest inventory variables is only 5%–15% larger using 50 field sample plots than the error of a linear model estimated with several hundred field sample plots when we sum up the error due to both the model noise variance and the model’s lack of fit.

Correlation between the synthetic origin of methamphetamine samples and their 15N and 13C stable isotope ratios

International Nuclear Information System (INIS)

Billault, Isabelle; Courant, Frederique; Pasquereau, Leo; Derrien, Solene; Robins, Richard J.; Naulet, Norbert

2007-01-01

The active ingredient of ecstasy, N-methyl-3,4-methyldioxyphenylisopropylamine (MDMA) can be manufactured by a number of easy routes from simple precursors. We have synthesised 45 samples of MDMA following the five most common routes using N-precursors from 12 different origins and three different precursors for the aromatic moiety. The 13 C and 15 N contents of both the precursors and the MDMA samples derived therefrom were measured by isotope ratio mass spectrometry coupled to an elemental analyser (EA-IRMS). We show that within-pathway correlation between the 15 N content of the precursor and that of the derived MDMA can be strong but that no general pattern of correlation can be defined. Rather, it is evident that the δ 15 N values of MDMA are strongly influenced by a combination of the δ 15 N values of the source of nitrogen used, the route by which the MDMA is synthesised, and the experimental conditions employed. Multivariate analysis (PCA) based on the δ 15 N values of the synthetic MDMA and of the δ 15 N and δ 13 C values of the N-precursors leads to good discrimination between the majority of the reaction conditions tested

Manifold Regularized Correlation Object Tracking

OpenAIRE

Hu, Hongwei; Ma, Bo; Shen, Jianbing; Shao, Ling

2017-01-01

In this paper, we propose a manifold regularized correlation tracking method with augmented samples. To make better use of the unlabeled data and the manifold structure of the sample space, a manifold regularization-based correlation filter is introduced, which aims to assign similar labels to neighbor samples. Meanwhile, the regression model is learned by exploiting the block-circulant structure of matrices resulting from the augmented translated samples over multiple base samples cropped fr...

An Exploratory Study of Spectroscopic Glutamatergic Correlates of Cortical Excitability in Depressed Adolescents

Directory of Open Access Journals (Sweden)

Charles P. Lewis

2016-11-01

Full Text Available Introduction: Transcranial magnetic stimulation (TMS research has suggested dysfunction in cortical glutamatergic systems in depression, while proton magnetic resonance spectroscopy (1H-MRS studies have demonstrated deficits in concentrations of glutamatergic metabolites in depressed individuals in several cortical regions, including the anterior cingulate cortex (ACC. However, few studies have combined TMS and MRS methods to examine relationships between glutamatergic neurochemistry and excitatory and inhibitory neural functions, and none have utilized TMS-MRS methodology in clinical populations or in youth. This exploratory study aimed to examine relationships between TMS measures of cortical excitability and inhibition and concentrations of glutamatergic metabolites as measured by 1H-MRS in depressed adolescents. Methods: Twenty-four children and adolescents (aged 11-18 years with depressive symptoms underwent TMS testing, which included measures of the resting motor threshold (RMT, cortical silent period (CSP, short-interval intracortical inhibition (SICI, and intracortical facilitation (ICF. Fourteen participants from the same sample also completed 1H-MRS in a 3 T MRI scanner after TMS testing. Glutamate + glutamine (Glx concentrations were measured in medial ACC and left primary motor cortex voxels with a TE-optimized PRESS sequence. Metabolite concentrations were corrected for cerebrospinal fluid after tissue segmentation. Pearson product-moment and Spearman rank-order correlations were calculated to assess relationships between TMS measures and Glx. Results: In the left primary motor cortex voxel, Glx had a significant positive correlation with the RMT. In the medial ACC voxel, Glx had significant positive correlations with ICF at the 10-ms and 20-ms ISIs.Conclusions: These preliminary data implicate glutamate in cortical excitatory processes measured by TMS. Limitations included small sample size, lack of healthy control comparators

Stability and reproducibility of a single-sample urinary C-peptide/creatinine ratio and its correlation with 24-h urinary C-peptide.

Science.gov (United States)

McDonald, Tim J; Knight, Bridget A; Shields, Beverley M; Bowman, Pamela; Salzmann, Maurice B; Hattersley, Andrew T

2009-11-01

C-peptide measurement in blood or 24-h urine samples provides useful information regarding endogenous insulin secretion, but problems related to the rapid degradation of C-peptide in blood and difficulty of 24-h urine collection have limited widespread routine clinical use of this test. We assessed the feasibility of measuring urinary C-peptide (UCP) with correction for creatinine concentration in single urine samples. We analyzed UCP using a routine electrochemiluminescence immunoassay in samples from 21 healthy volunteers. We investigated the stability of UCP with different preservatives and storage conditions and compared the reproducibility of urinary C-peptide/creatinine ratio (UCPCR) in first- and second-void fasting urines, then assessed correlations with 24-h collections. UCPCR was unchanged at room temperature for 24 h and at 4 degrees C for 72 h even in the absence of preservative. UCPCR collected in boric acid was stable at room temperature for 72 h. UCPCR remained stable after 7 freeze-thaw cycles but decreased with freezer storage time and dropped to 82%-84% of baseline by 90 days at -20 degrees C. Second-void fasting UCPCRs were lower than first-void (median 0.78 vs 1.31, P = 0.0003) and showed less variation (CV 33% vs 52%), as second-void UCPCRs were not influenced by evening food-related insulin secretion. Second-void fasting UCPCR was highly correlated with 24-h UCP (r = 0.8, P = 0.00006). Second-void fasting UCPCR is a reproducible measure that correlates well with 24-h UCP in normal samples. The 3-day stability of UCPCR at room temperature greatly increases its potential clinical utility.

Significance levels for studies with correlated test statistics.

Science.gov (United States)

Shi, Jianxin; Levinson, Douglas F; Whittemore, Alice S

2008-07-01

When testing large numbers of null hypotheses, one needs to assess the evidence against the global null hypothesis that none of the hypotheses is false. Such evidence typically is based on the test statistic of the largest magnitude, whose statistical significance is evaluated by permuting the sample units to simulate its null distribution. Efron (2007) has noted that correlation among the test statistics can induce substantial interstudy variation in the shapes of their histograms, which may cause misleading tail counts. Here, we show that permutation-based estimates of the overall significance level also can be misleading when the test statistics are correlated. We propose that such estimates be conditioned on a simple measure of the spread of the observed histogram, and we provide a method for obtaining conditional significance levels. We justify this conditioning using the conditionality principle described by Cox and Hinkley (1974). Application of the method to gene expression data illustrates the circumstances when conditional significance levels are needed.

Religiousness and preoperative anxiety: a correlational study

Directory of Open Access Journals (Sweden)

Karimollahi Mansoureh

2007-06-01

Full Text Available Abstract Background Major life changes are among factors that cause anxiety, and one of these changes is surgery. Emotional reactions to surgery have specific effects on the intensity and velocity as well as the process of physical disease. In addition, they can cause delay in patients recovery. This study is aimed at determining the relationship between religious beliefs and preoperative anxiety. Methods This survey is a correlational study to assess the relationship between religious beliefs and preoperative anxiety of patients undergoing abdominal, orthopaedic, and gynaecologic surgery in educational hospitals. We used the convenience sampling method. The data collection instruments included a questionnaire containing the Spielberger State-Trait Anxiety Inventory (STAI, and another questionnaire formulated by the researcher with queries on religious beliefs and demographic characteristics as well as disease-related information. Analysis of the data was carried out with SPSS software using descriptive and inferential statistics. Results were arranged in three tables. Results The findings showed that almost all the subjects had high level of religiosity and moderate level of anxiety. In addition, there was an inverse relationship between religiosity and intensity of anxiety, though this was not statistically significant. Conclusion The results of this study can be used as evidence for presenting religious counselling and spiritual interventions for individuals undergoing stress. Finally, based on the results of this study, the researcher suggested some recommendations for applying results and conducting further research.

Sample size of the reference sample in a case-augmented study.

Science.gov (United States)

Ghosh, Palash; Dewanji, Anup

2017-05-01

The case-augmented study, in which a case sample is augmented with a reference (random) sample from the source population with only covariates information known, is becoming popular in different areas of applied science such as pharmacovigilance, ecology, and econometrics. In general, the case sample is available from some source (for example, hospital database, case registry, etc.); however, the reference sample is required to be drawn from the corresponding source population. The required minimum size of the reference sample is an important issue in this regard. In this work, we address the minimum sample size calculation and discuss related issues. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

A Method to Correlate mRNA Expression Datasets Obtained from Fresh Frozen and Formalin-Fixed, Paraffin-Embedded Tissue Samples: A Matter of Thresholds.

Directory of Open Access Journals (Sweden)

Dana A M Mustafa

Full Text Available Gene expression profiling of tumors is a successful tool for the discovery of new cancer biomarkers and potential targets for the development of new therapeutic strategies. Reliable profiling is preferably performed on fresh frozen (FF tissues in which the quality of nucleic acids is better preserved than in formalin-fixed paraffin-embedded (FFPE material. However, since snap-freezing of biopsy materials is often not part of daily routine in pathology laboratories, one may have to rely on archival FFPE material. Procedures to retrieve the RNAs from FFPE materials have been developed and therefore, datasets obtained from FFPE and FF materials need to be made compatible to ensure reliable comparisons are possible.To develop an efficient method to compare gene expression profiles obtained from FFPE and FF samples using the same platform.Twenty-six FFPE-FF sample pairs of the same tumors representing various cancer types, and two FFPE-FF sample pairs of breast cancer cell lines, were included. Total RNA was extracted and gene expression profiling was carried out using Illumina's Whole-Genome cDNA-mediated Annealing, Selection, extension and Ligation (WG-DASL V3 arrays, enabling the simultaneous detection of 24,526 mRNA transcripts. A sample exclusion criterion was created based on the expression of 11 stably expressed reference genes. Pearson correlation at the probe level was calculated for paired FFPE-FF, and three cut-off values were chosen. Spearman correlation coefficients between the matched FFPE and FF samples were calculated for three probe lists with varying levels of significance and compared to the correlation based on all measured probes. Unsupervised hierarchical cluster analysis was performed to verify performance of the included probe lists to compare matched FPPE-FF samples.Twenty-seven FFPE-FF pairs passed the sample exclusion criterion. From the profiles of 27 FFPE and FF matched samples, the best correlating probes were identified

Transabdominal Chorionic Villous Sampling in Nigeria: Correlation ...

African Journals Online (AJOL)

BACKGROUND: transabdominal chorionic villous sampling is generally preferred to the transvaginal approach. The procedure may, however, be associated with complcations due to a number of factors. OBJECTIVES: to review the relationship between the number of cases and other variables in transabdominal chorionic ...

Suicidal ideation while incarcerated : prevalence and correlates in a large sample of male prisoners in Flanders, Belgium

OpenAIRE

Favril, Louis; Vander Laenen, Freya; Vandeviver, Christophe; Audenaert, Kurt

2017-01-01

Prisoners constitute a high-risk group for suicide. As an early stage in the pathway leading to suicide, suicidal ideation represents an important target for prevention, yet research on this topic is scarce in general prison populations. Using a cross-sectional survey design, correlates of suicidal ideation while incarcerated were examined in a sample of 1203 male prisoners, randomly selected from 15 Flemish prisons. Overall, a lifetime history of suicidal ideation and attempts was endorsed b...

Hope and spirituality among patients with chronic kidney disease undergoing hemodialysis: a correlational study

OpenAIRE

Ottaviani, Ana Carolina; Souza, Érica Nestor; Drago, Natália de Camargo; Mendiondo, Marisa Silvana Zazzetta de; Pavarini, Sofia Cristina Iost; Orlandi, Fabiana de Souza

2014-01-01

OBJECTIVE: to analyze the relationship between the hope and spirituality of patients with chronic kidney disease undergoing hemodialysis.METHOD: this is a cross-sectional, correlational study. The sample was composed of 127 patients of a Renal Replacement Unit. Data were collected through individual interviews guided by the following instruments: participant characterization, Herth Hope Index (HHI), and Pinto Pais-Ribeiro Spirituality Scale (PP-RSS).RESULTS: the average HHI score was 38.06 (±...

Image correlation spectroscopy: mapping correlations in space, time, and reciprocal space.

Science.gov (United States)

Wiseman, Paul W

2013-01-01

This chapter presents an overview of two recent implementations of image correlation spectroscopy (ICS). The background theory is presented for spatiotemporal image correlation spectroscopy and image cross-correlation spectroscopy (STICS and STICCS, respectively) as well as k-(reciprocal) space image correlation spectroscopy (kICS). An introduction to the background theory is followed by sections outlining procedural aspects for properly implementing STICS, STICCS, and kICS. These include microscopy image collection, sampling in space and time, sample and fluorescent probe requirements, signal to noise, and background considerations that are all required to properly implement the ICS methods. Finally, procedural steps for immobile population removal and actual implementation of the ICS analysis programs to fluorescence microscopy image time stacks are described. Copyright © 2013 Elsevier Inc. All rights reserved.

Fast patient-specific Monte Carlo brachytherapy dose calculations via the correlated sampling variance reduction technique

Energy Technology Data Exchange (ETDEWEB)

Sampson, Andrew; Le Yi; Williamson, Jeffrey F. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States)

2012-02-15

Purpose: To demonstrate potential of correlated sampling Monte Carlo (CMC) simulation to improve the calculation efficiency for permanent seed brachytherapy (PSB) implants without loss of accuracy. Methods: CMC was implemented within an in-house MC code family (PTRAN) and used to compute 3D dose distributions for two patient cases: a clinical PSB postimplant prostate CT imaging study and a simulated post lumpectomy breast PSB implant planned on a screening dedicated breast cone-beam CT patient exam. CMC tallies the dose difference, {Delta}D, between highly correlated histories in homogeneous and heterogeneous geometries. The heterogeneous geometry histories were derived from photon collisions sampled in a geometrically identical but purely homogeneous medium geometry, by altering their particle weights to correct for bias. The prostate case consisted of 78 Model-6711 {sup 125}I seeds. The breast case consisted of 87 Model-200 {sup 103}Pd seeds embedded around a simulated lumpectomy cavity. Systematic and random errors in CMC were unfolded using low-uncertainty uncorrelated MC (UMC) as the benchmark. CMC efficiency gains, relative to UMC, were computed for all voxels, and the mean was classified in regions that received minimum doses greater than 20%, 50%, and 90% of D{sub 90}, as well as for various anatomical regions. Results: Systematic errors in CMC relative to UMC were less than 0.6% for 99% of the voxels and 0.04% for 100% of the voxels for the prostate and breast cases, respectively. For a 1 x 1 x 1 mm{sup 3} dose grid, efficiency gains were realized in all structures with 38.1- and 59.8-fold average gains within the prostate and breast clinical target volumes (CTVs), respectively. Greater than 99% of the voxels within the prostate and breast CTVs experienced an efficiency gain. Additionally, it was shown that efficiency losses were confined to low dose regions while the largest gains were located where little difference exists between the homogeneous and

Latex Rubber Gloves as a Sampling Dosimeter Using a Novel Surrogate Sampling Device.

Science.gov (United States)

Sankaran, Gayatri; Lopez, Terry; Ries, Steve; Ross, John; Vega, Helen; Eastmond, David A; Krieger, Robert I

2015-01-01

Pesticide exposure during harvesting of crops occurs primarily to the workers' hands. When harvesters wear latex rubber gloves for personal safety and hygiene harvesting reasons, gloves accumulate pesticide residues. Hence, characterization of the gloves' properties may be useful for pesticide exposure assessments. Controlled field studies were conducted using latex rubber gloves to define the factors that influence the transfer of pesticides to the glove and that would affect their use as a residue monitoring device. A novel sampling device called the Brinkman Contact Transfer Unit (BCTU) was constructed to study the glove characteristics and residue transfer and accumulation under controlled conditions on turf. The effectiveness of latex rubber gloves as sampling dosimeters was evaluated by measuring the transferable pesticide residues as a function of time. The validation of latex rubber gloves as a residue sampling dosimeter was performed by comparing pesticide transfer and dissipation from the gloves, with the turf transferable residues sampled using the validated California (CA) Roller, a standard measure of residue transfer. The observed correlation (Pearson's correlation coefficient R(2)) between the two methods was .84 for malathion and .96 for fenpropathrin, indicating that the BCTU is a useful, reliable surrogate tool for studying available residue transfer to latex rubber gloves under experimental conditions. Perhaps more importantly, these data demonstrate that latex gloves worn by workers may be useful quantifiable matrices for measuring pesticide exposure.

Using Environmental Variables for Studying of the Quality of Sampling in Soil Mapping

OpenAIRE

A. Jafari; Norair Toomanian; R. Taghizadeh Mehrjerdi

2016-01-01

Introduction: Methods of soil survey are generally empirical and based on the mental development of the surveyor, correlating soil with underlying geology, landforms, vegetation and air-photo interpretation. Since there are no statistical criteria for traditional soil sampling; this may lead to bias in the areas being sampled. In digital soil mapping, soil samples may be used to elaborate quantitative relationships or models between soil attributes and soil covariates. Because the relationshi...

A Study on the Correlation between Pain and Pain Anxiety during Wound Care in Burn Patients

Directory of Open Access Journals (Sweden)

Seyed Reza Mazlom

2017-05-01

Full Text Available Background and Objectives: Wound care in burn patients is associated with severe anxiety that is characterized by feeling of fear and prediction of burn dressing pain. The purpose of this study was to determine the correlation between pain and pain anxiety in burn patients. Methods: In this descriptive-analytical study, 60 eligible patients hospitalized in men’s and women’s burn wards of Mashhad Imam Reza Hospital, were selected using available sampling. Pain anxiety and pain severity were measured using self-report pain anxiety questionnaire and visual analog scale, respectively, before and after burn dressing during three weeks (once a week. Data were analyzed by descriptive statistics and Pearson correlation test. Results: In this study, there was a significant linear correlation between pain and pain anxiety in the first week (r=0.512, p<0.001, but there was no significant linear correlation between these variables in the second (r=0.079, p=0.547 and third (r=0.167, p=0.203 weeks. Conclusion: According to the results of this study, assessment and treatment of pain anxiety are essential elements of pain care and management in burn patients.            

Correlation of trace metals in hair and nails

International Nuclear Information System (INIS)

Benischek-Huber, I.; Benischek, F.

1985-01-01

Correlation of Cd, Cu, Hg, Pb and Zn was studied in 350 hair and nail samples of 12 persons. Determination was performed by atomic absorption spectrometry. Cd, Pb and Hg concentrations are fluctuating significantly in the specimens. Correlation was found for these elements in hair and finger nails and for Pb in hair and toe nails. Zn and Cu are more stable, the ratios of contents in corresponding samples are within a small range. (author)

The Bose-Einstein correlations in CDFII experiment

Energy Technology Data Exchange (ETDEWEB)

Lovás, Lubomír [Comenius Univ., Bratislava (Slovakia)

2008-01-01

We present the results of a study of p$\\bar{p}$ collisions at √s = 1.96 TeV collected by the CDF-II experiment at Tevatron collider. The Bose-Einstein correlations of the π^±π^± two boson system have been studied in the minimum-bias high-multiplicity events. The research was carried out on the sample at the size of 173761 events. The two pion correlations have been retrieved. The final results were corrected to the coulomb interactions. Two different reference samples were compared and discussed. A significant two-pion correlation enhancement near origin is observed. This enhancement effect has been used to evaluate the radius of the two-pion emitter source. We have used the TOF detector to distinguish between π and K mesons. The C₂(Q) function parameters have also been retrieved for the sample containing only tagged π mesons. A comparison between four different parametrizations based on two diff t theoretical approaches of the C₂(Q) function is given.

Strength and deformability of hollow concrete blocks: correlation of block and cylindrical sample test results

Directory of Open Access Journals (Sweden)

C. S. Barbosa

Full Text Available This paper deals with correlations among mechanical properties of hollow blocks and those of concrete used to make them. Concrete hollow blocks and test samples were moulded with plastic consistency concrete, to assure the same material in all cases, in three diferente levels of strength (nominally 10 N/mm², 20 N/mm² and 30 N/mm². The mechanical properties and structural behaviour in axial compression and tension tests were determined by standard tests in blocks and cylinders. Stress and strain analyses were made based on concrete’s modulus of elasticity obtained in the sample tests as well as on measured strain in the blocks’ face-shells and webs. A peculiar stress-strain analysis, based on the superposition of effects, provided an estimation of the block load capacity based on its deformations. In addition, a tentative method to preview the block deformability from the concrete mechanical properties is described and tested. This analysis is a part of a broader research that aims to support a detailed structural analysis of blocks, prisms and masonry constructions.

Correlates of Total Sedentary Time and Screen Time in 9-11 Year-Old Children around the World: The International Study of Childhood Obesity, Lifestyle and the Environment.

Science.gov (United States)

LeBlanc, Allana G; Katzmarzyk, Peter T; Barreira, Tiago V; Broyles, Stephanie T; Chaput, Jean-Philippe; Church, Timothy S; Fogelholm, Mikael; Harrington, Deirdre M; Hu, Gang; Kuriyan, Rebecca; Kurpad, Anura; Lambert, Estelle V; Maher, Carol; Maia, José; Matsudo, Victor; Olds, Timothy; Onywera, Vincent; Sarmiento, Olga L; Standage, Martyn; Tudor-Locke, Catrine; Zhao, Pei; Tremblay, Mark S

2015-01-01

Previously, studies examining correlates of sedentary behavior have been limited by small sample size, restricted geographic area, and little socio-cultural variability. Further, few studies have examined correlates of total sedentary time (SED) and screen time (ST) in the same population. This study aimed to investigate correlates of SED and ST in children around the world. The sample included 5,844 children (45.6% boys, mean age = 10.4 years) from study sites in Australia, Brazil, Canada, China, Colombia, Finland, India, Kenya, Portugal, South Africa, the United Kingdom, and the United States. Child- and parent-reported behavioral, household, and neighborhood characteristics and directly measured anthropometric and accelerometer data were obtained. Twenty-one potential correlates of SED and ST were examined using multilevel models, adjusting for sex, age, and highest parental education, with school and study site as random effects. Variables that were moderately associated with SED and/or ST in univariate analyses (pcomputer in the bedroom. In this global sample many common correlates of SED and ST were identified, some of which are easily modifiable (e.g., removing TV from the bedroom), and others that may require more intense behavioral interventions (e.g., increasing physical activity). Future work should incorporate these findings into the development of culturally meaningful public health messages.

Manifold Regularized Correlation Object Tracking.

Science.gov (United States)

Hu, Hongwei; Ma, Bo; Shen, Jianbing; Shao, Ling

2018-05-01

In this paper, we propose a manifold regularized correlation tracking method with augmented samples. To make better use of the unlabeled data and the manifold structure of the sample space, a manifold regularization-based correlation filter is introduced, which aims to assign similar labels to neighbor samples. Meanwhile, the regression model is learned by exploiting the block-circulant structure of matrices resulting from the augmented translated samples over multiple base samples cropped from both target and nontarget regions. Thus, the final classifier in our method is trained with positive, negative, and unlabeled base samples, which is a semisupervised learning framework. A block optimization strategy is further introduced to learn a manifold regularization-based correlation filter for efficient online tracking. Experiments on two public tracking data sets demonstrate the superior performance of our tracker compared with the state-of-the-art tracking approaches.

Patterns and correlates of physical activity among middle-aged employees: a population-based, cross-sectional study.

Science.gov (United States)

Jurakic, Danijel; Golubić, Antonija; Pedisic, Zeljko; Pori, Maja

2014-06-01

The purpose of this study was to determine the level, pattern and correlates (socio-demographic, lifestyle and work-related) of physical activity among middle-aged employees in Croatia. In this cross-sectional study the data were collected using a household interview on a random sample of 766 middle-aged employees (52% female) living in Croatia. The International Physical Activity Questionnaire (IPAQ-long) was used to assess physical activity. An additional questionnaire was used to collect data on socio-demographic, lifestyle and work-related correlates. The median (95% CI) total physical activity for the whole sample was 78.7 (69.1-88.3) MET-hours/week. Most physical activity was accumulated in the domain of work (26.4 (20.3-32.5) MET-hours/week) or in domestic activities (19.2(17.8-20.7) MET-hours/week), whilst a significantly lower physical activity was found in the transport (3.3 (2.9-3.7) MET-hours/week) and leisure-time domains (6.5 (5.7-7.3) MET-hours/week). The multiple regression analysis showed an inverse relationship between educational level and the size of settlements with the domestic-related and total physical activity (β range: -0.11 to -0.22; p physical activity (β = 0.12; p physical activity (β = -0.10; p employees in Croatia accumulate most of their daily physical activity in the work and domestic domains. Analysis of the relationship between physical activity and potential socio-demographic, lifestyle, and work-related correlates indicated that physical activity promotional activities should be primarily focused on males, employees living in smaller settlements and those with higher educational levels. The correlates of physical activity among middle-aged employees seem to be domain-specific. Therefore, future studies in this area should consider assessing physical activity in each domain separately.

Correlates of daily leisure-time physical activity in a community sample : Narrow personality traits and practical barriers

NARCIS (Netherlands)

Gallagher, P.; Yancy, W.S.; Denissen, J.J.A.; Kühnel, A.; Voils, C.I.

2013-01-01

Objective: Previous studies examining correlates of leisure time physical activity (LTPA) have identified personality factors that are correlated with LTPA and practical factors that impede LTPA. The purpose of the present study was to test how several narrow traits predict daily reports of LTPA and

Total lead (Pb) concentration in oil shale ash samples based on correlation to isotope Pb-210 gamma-spectrometric measurements

Energy Technology Data Exchange (ETDEWEB)

Vaasma, T.; Kiisk, M.; Tkaczyk, A.H. [University of Tartu (Estonia); Bitjukova, L. [Tallinn University of Technology (Estonia)

2014-07-01

(PF) and circulating fluidized bed (CFB) firing technology. These samples were analyzed to determine macro and trace elements by the ICP-MS method. The same samples were also measured with a high-purity germanium detector (planar BSI GPD-50400) to determine the activity concentrations of natural radionuclides. The lead concentrations and Pb-210 activity concentrations were determined, and the correlation between the corresponding values was analyzed. Initial results demonstrate a strong positive linear relationship between these values, with the coefficient of determination (R{sup 2}) over 94. The correlation coefficient (Pearson's, 'r') had a value over 0.95. Both Pb and Pb-210 values had an increasing trend from the bottom ash towards electrostatic precipitator (ESP) ashes. The strong linear correlation between Pb concentrations and Pb-210 activity concentrations gives a credible indication that lead can be measured in ash samples using its radioactive isotope Pb-210. Especially in situations where there are higher concentrations of Pb, for example in the case of wastes from the metallurgic and energy industries, this method could be used to detect the lead concentration quickly and with no chemical processing of the sample. Document available in abstract form only. (authors)

Deciphering the Correlation between Breast Tumor Samples and Cell Lines by Integrating Copy Number Changes and Gene Expression Profiles

Directory of Open Access Journals (Sweden)

Yi Sun

2015-01-01

Full Text Available Breast cancer is one of the most common cancers with high incident rate and high mortality rate worldwide. Although different breast cancer cell lines were widely used in laboratory investigations, accumulated evidences have indicated that genomic differences exist between cancer cell lines and tissue samples in the past decades. The abundant molecular profiles of cancer cell lines and tumor samples deposited in the Cancer Cell Line Encyclopedia and The Cancer Genome Atlas now allow a systematical comparison of the breast cancer cell lines with breast tumors. We depicted the genomic characteristics of breast primary tumors based on the copy number variation and gene expression profiles and the breast cancer cell lines were compared to different subgroups of breast tumors. We identified that some of the breast cancer cell lines show high correlation with the tumor group that agrees with previous knowledge, while a big part of them do not, including the most used MCF7, MDA-MB-231, and T-47D. We presented a computational framework to identify cell lines that mostly resemble a certain tumor group for the breast tumor study. Our investigation presents a useful guide to bridge the gap between cell lines and tumors and helps to select the most suitable cell line models for personalized cancer studies.

Investigating correlates of synthetic marijuana and Salvia use in light and intermittent smokers and college students in a predominantly Hispanic sample.

Science.gov (United States)

Gutierrez, Kevin M; Cooper, Theodore V

2014-12-01

Few studies have examined correlates related to the use of synthetic cannabinoids (e.g., Spice, K2) and Salvia divinorum. Two studies were conducted to investigate whether demographic, smoking-related, and substance-related variables were associated with the use of synthetic cannabinoids and Salvia. In Study 1, 185 participants (50% female; 83% Hispanic; Mage = 32 years; SD = 13.68) were recruited from a local health clinic and a university on the U.S./Mexico border for a smoking-cessation study targeting light and intermittent smokers. In Study 2, 675 participants (62.4% female; 89.1% Hispanic; Mage = 21.0, SD = 8.56) were recruited from a university on the U.S./Mexico border for an online study. In Study 1, 10% of the sample indicated they had ever used either synthetic cannabinoids or Salvia in their lifetime. Being male and dual/multiple use of tobacco products were significantly associated with having ever used synthetic cannabinoids or Salvia. In Study 2, 9%, 5%, and 3% of the sample indicated lifetime, past-year, and past 30-day use of synthetic cannabinoids, respectively. Five percent, 2%, and 1% of the sample indicated lifetime, past-year, and past 30-day use of Salvia, respectively. Logistic regression analyses revealed that past 30-day marijuana use and past 30-day ecstasy use were significantly associated with use of synthetic cannabinoids and Salvia in one's lifetime. These findings suggest that the assessment of synthetic marijuana and Salvia use is warranted in studies of other addictive behaviors, particularly among current marijuana and ecstasy users. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Neutron scattering studies of spin correlations in metallic YBa2Cu3O6+x

International Nuclear Information System (INIS)

Tranquada, J.M.

1991-01-01

Electron-electron correlations appear to play an important role in determining many properties of the copper oxide superconductors. One significant consequence of the electronic coulomb interactions are spin correlations. In the insulating phases of the layered cuprates, where the antibonding band due to Cu 3d x 2 - y 2 -O 2p σ hybridization in the CuO 2 planes is half filled, long-range antiferromagnetic order is observed. As the layers are doped with holes, the Neel order is rapidly destroyed, but dynamical antiferromagnetic correlations survive. In this paper, I will review some inelastic neutron scattering studies of the spin fluctuations in metallic YBa 2 Cu 3 O 6+x . The paper is organized as follows. In the first section I briefly discuss some background information concerning the phase diagram and spin waves in the insulating phase. Experimental results on metallic YBa 2 Cu 3 O 6+x samples are presented in the second section. The interpretation of these results and their relationship to nuclear magnetic resonance (NMR) studies and to theory are discussed in the final section

The correlation of arsenic levels in drinking water with the biological samples of skin disorders

Energy Technology Data Exchange (ETDEWEB)

Kazi, Tasneem Gul [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: tgkazi@yahoo.com; Arain, Muhammad Balal [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: bilal_ku2004@yahoo.com; Baig, Jameel Ahmed [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: jab_mughal@yahoo.com; Jamali, Muhammad Khan [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: mkhanjamali@yahoo.com; Afridi, Hassan Imran [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: hassanimranafridi@yahoo.com; Jalbani, Nusrat [Pakistan Council for Scientific and Industrial Research, University Road Karachi-75280 (Pakistan)], E-mail: nusratjalbani_21@yahoo.com; Sarfraz, Raja Adil [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: rajaadilsarfraz@gmail.com; Shah, Abdul Qadir [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: aqshah07@yahoo.com; Niaz, Abdul [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: niazchemist2k6@yahoo.com

2009-01-15

Arsenic (As) poisoning has become a worldwide public health concern. The skin is quite sensitive to As and skin lesions are the most common and earliest nonmalignant effects associated to chronic As exposure. In 2005-2007, a survey was carried out on surface and groundwater arsenic contamination and relationships between As exposure via the drinking water and related adverse health effects (melanosis and keratosis) on villagers resides on the banks of Manchar lake, southern part of Sindh, Pakistan. We screened the population from arsenic-affected villages, 61 to 73% population were identified patients suffering from chronic arsenic toxicity. The effects of As toxicity via drinking water were estimated by biological samples (scalp hair and blood) of adults (males and females), have or have not skin problem (n = 187). The referent samples of both genders were also collected from the areas having low level of As (< 10 {mu}g/L) in drinking water (n = 121). Arsenic concentration in drinking water and biological samples were analyzed using electrothermal atomic absorption spectrometry. The range of arsenic concentrations in lake surface water was 35.2-158 {mu}g/L, which is 3-15 folds higher than World Health Organization [WHO, 2004. Guidelines for drinking-water quality third ed., WHO Geneva Switzerland.]. It was observed that As concentration in the scalp hair and blood samples were above the range of permissible values 0.034-0.319 {mu}g As/g for hair and < 0.5-4.2 {mu}g/L for blood. The linear regressions showed good correlations between arsenic concentrations in water versus hair and blood samples of exposed skin diseased subjects (R{sup 2} = 0.852 and 0.718) as compared to non-diseased subjects (R{sup 2} = 0.573 and 0.351), respectively.

Two sampling techniques for game meat

OpenAIRE

van der Merwe, Maretha; Jooste, Piet J.; Hoffman, Louw C.; Calitz, Frikkie J.

2013-01-01

A study was conducted to compare the excision sampling technique used by the export market and the sampling technique preferred by European countries, namely the biotrace cattle and swine test. The measuring unit for the excision sampling was grams (g) and square centimetres (cm2) for the swabbing technique. The two techniques were compared after a pilot test was conducted on spiked approved beef carcasses (n = 12) that statistically proved the two measuring units correlated. The two sampling...

Study of Acoustic Emission and Mechanical Characteristics of Coal Samples under Different Loading Rates

Directory of Open Access Journals (Sweden)

Huamin Li

2015-01-01

Full Text Available To study the effect of loading rate on mechanical properties and acoustic emission characteristics of coal samples, collected from Sanjiaohe Colliery, the uniaxial compression tests are carried out under various levels of loading rates, including 0.001 mm/s, 0.002 mm/s, and 0.005 mm/s, respectively, using AE-win E1.86 acoustic emission instrument and RMT-150C rock mechanics test system. The results indicate that the loading rate has a strong impact on peak stress and peak strain of coal samples, but the effect of loading rate on elasticity modulus of coal samples is relatively small. When the loading rate increases from 0.001 mm/s to 0.002 mm/s, the peak stress increases from 22.67 MPa to 24.99 MPa, the incremental percentage is 10.23%, and under the same condition the peak strain increases from 0.006191 to 0.007411 and the incremental percentage is 19.71%. Similarly, when the loading rate increases from 0.002 mm/s to 0.005 mm/s, the peak stress increases from 24.99 MPa to 28.01 MPa, the incremental percentage is 12.08%, the peak strain increases from 0.007411 to 0.008203, and the incremental percentage is 10.69%. The relationship between acoustic emission and loading rate presents a positive correlation, and the negative correlation relation has been determined between acoustic emission cumulative counts and loading rate during the rupture process of coal samples.

Comparing identified and statistically significant lipids and polar metabolites in 15-year old serum and dried blood spot samples for longitudinal studies: Comparing lipids and metabolites in serum and DBS samples

Energy Technology Data Exchange (ETDEWEB)

Kyle, Jennifer E. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Casey, Cameron P. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Stratton, Kelly G. [National Security Directorate, Pacific Northwest National Laboratory, Richland WA USA; Zink, Erika M. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Kim, Young-Mo [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Zheng, Xueyun [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Monroe, Matthew E. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Weitz, Karl K. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Bloodsworth, Kent J. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Orton, Daniel J. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Ibrahim, Yehia M. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Moore, Ronald J. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Lee, Christine G. [Department of Medicine, Bone and Mineral Unit, Oregon Health and Science University, Portland OR USA; Research Service, Portland Veterans Affairs Medical Center, Portland OR USA; Pedersen, Catherine [Department of Medicine, Bone and Mineral Unit, Oregon Health and Science University, Portland OR USA; Orwoll, Eric [Department of Medicine, Bone and Mineral Unit, Oregon Health and Science University, Portland OR USA; Smith, Richard D. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Burnum-Johnson, Kristin E. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Baker, Erin S. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA

2017-02-05

The use of dried blood spots (DBS) has many advantages over traditional plasma and serum samples such as smaller blood volume required, storage at room temperature, and ability for sampling in remote locations. However, understanding the robustness of different analytes in DBS samples is essential, especially in older samples collected for longitudinal studies. Here we analyzed DBS samples collected in 2000-2001 and stored at room temperature and compared them to matched serum samples stored at -80°C to determine if they could be effectively used as specific time points in a longitudinal study following metabolic disease. Four hundred small molecules were identified in both the serum and DBS samples using gas chromatograph-mass spectrometry (GC-MS), liquid chromatography-MS (LC-MS) and LC-ion mobility spectrometry-MS (LC-IMS-MS). The identified polar metabolites overlapped well between the sample types, though only one statistically significant polar metabolite in a case-control study was conserved, indicating degradation occurs in the DBS samples affecting quantitation. Differences in the lipid identifications indicated that some oxidation occurs in the DBS samples. However, thirty-six statistically significant lipids correlated in both sample types indicating that lipid quantitation was more stable across the sample types.

The heritability and genetic correlates of mobile phone use: a twin study of consumer behavior.

Science.gov (United States)

Miller, Geoffrey; Zhu, Gu; Wright, Margaret J; Hansell, Narelle K; Martin, Nicholas G

2012-02-01

There has been almost no overlap between behavior genetics and consumer behavior research, despite each field's importance in understanding society. In particular, both have neglected to study genetic influences on consumer adoption and usage of new technologies -- even technologies as important as the mobile phone, now used by 5.8 out of 7.0 billion people on earth. To start filling this gap, we analyzed self-reported mobile phone use, intelligence, and personality traits in two samples of Australian teenaged twins (mean ages 14.2 and 15.6 years), totaling 1,036 individuals. ACE modeling using Mx software showed substantial heritabilities for how often teens make voice calls (.60 and .34 in samples 1 and 2, respectively) and for how often they send text messages (.53 and. 50). Shared family environment - including neighborhood, social class, parental education, and parental income (i.e., the generosity of calling plans that parents can afford for their teens) -- had much weaker effects. Multivariate modeling based on cross-twin, cross-trait correlations showed negative genetic correlations between talking/texting frequency and intelligence (around -.17), and positive genetic correlations between talking/texting frequency and extraversion (about .20 to .40). Our results have implications for assessing the risks of mobile phone use such as radiofrequency field (RF) exposure and driving accidents, for studying adoption and use of other emerging technologies, for understanding the genetic architecture of the cognitive and personality traits that predict consumer behavior, and for challenging the common assumption that consumer behavior is shaped entirely by culture, media, and family environment.

A correlational and predictive study of creativity and personality of college students.

Science.gov (United States)

Sanz de Acedo Baquedano, María Teresa; Sanz de Acedo Lizarraga, María Luisa

2012-11-01

The goals of this study were to examine the relationship between creativity and personality, to identify what personality variables better predict creativity, and to determine whether significant differences exist among them in relation to gender. The research was conducted with a sample of 87 students at the Universidad Pública de Navarra, Spain. We administered the Creative Intelligence Test (CREA), which provides a cognitive measure for creativity and the Situational Personality Questionnaire (SPQ), which is composed of 15 personality features. Positive and significant correlations between creativity and independence, cognitive control, and tolerance personality scales were found. Negative and significant correlations between creativity and anxious, dominant, and aggressive personalities were also found. Moreover, four personality variables that positively predicted creativity (efficacy, independence, cognitive control, and integrity-honesty) and another four that negatively predicted creativity (emotional stability, anxiety, dominance, and leadership) were identified. The results did not show significant differences in creativity and personality in relation to gender, except in self-concept and in social adjustment. In conclusion, the results from this study can potentially be used to expand the types of features that support creative personalities.

Study of local correlations of magnetic and multiferroic compounds

CERN Multimedia

Alves, E J

We propose to study magnetic and multiferroic strongly correlated electron materials using radioactive nuclear probe techniques, at ISOLDE . Following the strategy of a previous project, IS390, our aim is to provide local and element selective information on some of the mechanisms that rule structural, charge and orbital correlations, electronic and magnetic interactions and the coupling of the associated degrees of freedom. The main technique used is Perturbed Angular Correlations (PAC), which allows combined magnetic and electric hyperfine studies. This study is complemented by the use of conventional characterisation techniques, and the investigation of relevant macroscopic properties.

Distortion of two-pion interferometry by multipion correlations

International Nuclear Information System (INIS)

Zhang, W.N.; Liu, Y.M.; Wang, S.; Liu, Q.J.; Jiang, J.; Keane, D.; Shao, Y.; Chu, S.Y.; Fung, S.Y.

1993-01-01

Multipion correlations arising from the symmetrization of the n-pion wave function affect the extracted information from two-pion correlation measurements. The influence of multipion correlations on a sample of like-pion pairs can be expressed as a multipion correlation factor, the distribution of which offers good sensitivity to the multipion correlation effect. Analyses of the multipion correlation factor for two Bevalac streamer chamber data samples of 2.1A GeV Ne+Pb and 1.8A GeV Ar+Pb collisions show that the multipion correlation effect in the former sample is greater than in the latter. This result mainly arises from the fact that the pion source for Ne projectiles is smaller than for Ar projectiles. The residual correlations in the reference sample are related to the multipion correlation factor in multipion events, which can be expressed as a residual correlation factor. The influence of multipion correlations on two-pion interferometry analyses arises from the ratio of the residual correlation factor to the multipion correlation factor

Mental health and clinical correlates in lesbian, gay, bisexual, and queer young adults

DEFF Research Database (Denmark)

Grant, Jon E; Odlaug, Brian Lawrence; Derbyshire, Katherine

2014-01-01

This study examined the prevalence of mental health disorders and their clinical correlates in a university sample of lesbian, gay, bisexual, and queer (LGBQ) students.......This study examined the prevalence of mental health disorders and their clinical correlates in a university sample of lesbian, gay, bisexual, and queer (LGBQ) students....

Statistical Study of Turbulence: Spectral Functions and Correlation Coefficients

Science.gov (United States)

Frenkiel, Francois N.

1958-01-01

In reading the publications on turbulence of different authors, one often runs the risk of confusing the various correlation coefficients and turbulence spectra. We have made a point of defining, by appropriate concepts, the differences which exist between these functions. Besides, we introduce in the symbols a few new characteristics of turbulence. In the first chapter, we study some relations between the correlation coefficients and the different turbulence spectra. Certain relations are given by means of demonstrations which could be called intuitive rather than mathematical. In this way we demonstrate that the correlation coefficients between the simultaneous turbulent velocities at two points are identical, whether studied in Lagrange's or in Euler's systems. We then consider new spectra of turbulence, obtained by study of the simultaneous velocities along a straight line of given direction. We determine some relations between these spectra and the correlation coefficients. Examining the relation between the spectrum of the turbulence measured at a fixed point and the longitudinal-correlation curve given by G. I. Taylor, we find that this equation is exact only when the coefficient is very small.

Alexithymia: its prevalence and correlates in a British undergraduate sample.

Science.gov (United States)

Mason, O; Tyson, M; Jones, C; Potts, S

2005-03-01

Alexithymia is characterized by a difficulty identifying and describing emotional states, as well as an externally oriented thinking style. This study investigated the prevalence of alexithymia in a British undergraduate sample and assesses its relationship to both parental bonding and dissociation. The Toronto alexithymia scale (TAS-20), the Parental Bonding Instrument (PBI), and the Dissociative Experience Scale (DES) were administered to a sample of 181 male and 190 female undergraduate students from both arts and science subjects. Rates of alexithymia were comparable with those observed in some other countries. Contrary to predictions, females were found to have higher rates than males, and the highest presence of alexithymia was in female science students. As in previous studies, alexithymia was linked to both dissociation and perceptions of a lack of maternal care, though the degree of association to the latter was small. Dissociative experiences were predicted by both maternal overprotection and difficulties identifying feelings. Some qualified support was found for the relevance of early maternal bonding to later difficulties processing emotions. The presence of greater alexithymia in females, and female science students in particular, was discussed in reference to similar observations elsewhere. There was also an understandable relationship between 'difficulty identifying feelings' (TAS) and both depersonalization/derealization and absorption (DES).

Neuropsychological profiles correlated with clinical and behavioral impairments in a sample of Brazilian children with Attention Deficit Hyperactivity Disorder (ADHD

Directory of Open Access Journals (Sweden)

Sueli eRizzutti

2015-11-01

Full Text Available ADHD is a complex neurodevelopmental disorder that implies several-step process and there is no single test to diagnose both ADHD and associated comorbidities such as oppositional defiant disorder, anxiety disorder, depression and certain types of learning disabilities. The purpose of the present study was to examine correlations between behavioral and clinical symptoms by administering an extensive neuropsychological battery to a sample of children and adolescents from a developing country. The sample was divided into three groups: non-ADHD; ADHD-non-comorbid; and ADHD+comorbidity. A full neuropsychological battery and clinical assessment found that 105 children met DSM-5 criteria, of whom 46.6% had the predominantly inattentive presentation, 37.3% had combined presentation and 16% were predominantly hyperactive/impulsive presentation. The internal correlation between neuropsychological tests did not reach statistical significance in the comparison between ADHD and non-ADHD cases (p<0.17. Clinical ADHD cases, including both +comorbidity and non-comorbid groups, performed substantially worse on CPT, working memory. Comparing ADHD-non-comorbid and ADHD+comorbidity groups, the latter did significantly worse on inhibitory control, time processing and the level of perseveration response on CPT indexes, as well as on working memory performance and CBCL tests particularly the CBCL-DESR (deficient emotional self-regulation test in the ADHD+comorbidity group. Children diagnosed as oppositional-defiant (ODD or with conduct disorder (CD showed close correlations between clinical CBCL profiles and externalized symptoms. Our findings suggest that ADHD+comorbidity and ADHD non-comorbid cases may be differentiated by a number of neuropsychological measures, such as processing speed, inhibitory control and working memory, that may reflect different levels of involvement of the hot and cool executive domains, which are more impaired in cases of severe

Influence of population versus convenience sampling on sample characteristics in studies of cognitive aging.

Science.gov (United States)

Brodaty, Henry; Mothakunnel, Annu; de Vel-Palumbo, Melissa; Ames, David; Ellis, Kathryn A; Reppermund, Simone; Kochan, Nicole A; Savage, Greg; Trollor, Julian N; Crawford, John; Sachdev, Perminder S

2014-01-01

We examined whether differences in findings of studies examining mild cognitive impairment (MCI) were associated with recruitment methods by comparing sample characteristics in two contemporaneous Australian studies, using population-based and convenience sampling. The Sydney Memory and Aging Study invited participants randomly from the electoral roll in defined geographic areas in Sydney. The Australian Imaging, Biomarkers and Lifestyle Study of Ageing recruited cognitively normal (CN) individuals via media appeals and MCI participants via referrals from clinicians in Melbourne and Perth. Demographic and cognitive variables were harmonized, and similar diagnostic criteria were applied to both samples retrospectively. CN participants recruited via convenience sampling were younger, better educated, more likely to be married and have a family history of dementia, and performed better cognitively than those recruited via population-based sampling. MCI participants recruited via population-based sampling had better memory performance and were less likely to carry the apolipoprotein E ε4 allele than clinically referred participants but did not differ on other demographic variables. A convenience sample of normal controls is likely to be younger and better functioning and that of an MCI group likely to perform worse than a purportedly random sample. Sampling bias should be considered when interpreting findings. Copyright © 2014 Elsevier Inc. All rights reserved.

Random matrix theory analysis of cross-correlations in the US stock market: Evidence from Pearson’s correlation coefficient and detrended cross-correlation coefficient

Science.gov (United States)

Wang, Gang-Jin; Xie, Chi; Chen, Shou; Yang, Jiao-Jiao; Yang, Ming-Yan

2013-09-01

In this study, we first build two empirical cross-correlation matrices in the US stock market by two different methods, namely the Pearson’s correlation coefficient and the detrended cross-correlation coefficient (DCCA coefficient). Then, combining the two matrices with the method of random matrix theory (RMT), we mainly investigate the statistical properties of cross-correlations in the US stock market. We choose the daily closing prices of 462 constituent stocks of S&P 500 index as the research objects and select the sample data from January 3, 2005 to August 31, 2012. In the empirical analysis, we examine the statistical properties of cross-correlation coefficients, the distribution of eigenvalues, the distribution of eigenvector components, and the inverse participation ratio. From the two methods, we find some new results of the cross-correlations in the US stock market in our study, which are different from the conclusions reached by previous studies. The empirical cross-correlation matrices constructed by the DCCA coefficient show several interesting properties at different time scales in the US stock market, which are useful to the risk management and optimal portfolio selection, especially to the diversity of the asset portfolio. It will be an interesting and meaningful work to find the theoretical eigenvalue distribution of a completely random matrix R for the DCCA coefficient because it does not obey the Marčenko-Pastur distribution.

Degeneracy and long-range correlation: A simulation study

Directory of Open Access Journals (Sweden)

Marmelat Vivien

2011-12-01

Full Text Available We present in this paper a simulation study that aimed at evidencing a causal relationship between degeneracy and long-range correlations. Long-range correlations represent a very specific form of fluctuations that have been evidenced in the outcomes time series produced by a number of natural systems. Long-range correlations are supposed to sign the complexity, adaptability and flexibility of the system. Degeneracy is defined as the ability of elements that are structurally different to perform the same function, and is presented as a key feature for explaining the robustness of complex systems. We propose a model able to generate long-range correlated series, and including a parameter that account for degeneracy. Results show that a decrease in degeneracy tends to reduce the strength of long-range correlation in the series produced by the model.

Neural correlates of emotional personality: a structural and functional magnetic resonance imaging study.

Directory of Open Access Journals (Sweden)

Stefan Koelsch

Full Text Available Studies addressing brain correlates of emotional personality have remained sparse, despite the involvement of emotional personality in health and well-being. This study investigates structural and functional brain correlates of psychological and physiological measures related to emotional personality. Psychological measures included neuroticism, extraversion, and agreeableness scores, as assessed using a standard personality questionnaire. As a physiological measure we used a cardiac amplitude signature, the so-called E κ value (computed from the electrocardiogram which has previously been related to tender emotionality. Questionnaire scores and E κ values were related to both functional (eigenvector centrality mapping, ECM and structural (voxel-based morphometry, VBM neuroimaging data. Functional magnetic resonance imaging (fMRI data were obtained from 22 individuals (12 females while listening to music (joy, fear, or neutral music. ECM results showed that agreeableness scores correlated with centrality values in the dorsolateral prefrontal cortex, the anterior cingulate cortex, and the ventral striatum (nucleus accumbens. Individuals with higher E κ values (indexing higher tender emotionality showed higher centrality values in the subiculum of the right hippocampal formation. Structural MRI data from an independent sample of 59 individuals (34 females showed that neuroticism scores correlated with volume of the left amygdaloid complex. In addition, individuals with higher E κ showed larger gray matter volume in the same portion of the subiculum in which individuals with higher E κ showed higher centrality values. Our results highlight a role of the amygdala in neuroticism. Moreover, they indicate that a cardiac signature related to emotionality (E κ correlates with both function (increased network centrality and structure (grey matter volume of the subiculum of the hippocampal formation, suggesting a role of the hippocampal formation for

Neural correlates of emotional personality: a structural and functional magnetic resonance imaging study.

Science.gov (United States)

Koelsch, Stefan; Skouras, Stavros; Jentschke, Sebastian

2013-01-01

Studies addressing brain correlates of emotional personality have remained sparse, despite the involvement of emotional personality in health and well-being. This study investigates structural and functional brain correlates of psychological and physiological measures related to emotional personality. Psychological measures included neuroticism, extraversion, and agreeableness scores, as assessed using a standard personality questionnaire. As a physiological measure we used a cardiac amplitude signature, the so-called E κ value (computed from the electrocardiogram) which has previously been related to tender emotionality. Questionnaire scores and E κ values were related to both functional (eigenvector centrality mapping, ECM) and structural (voxel-based morphometry, VBM) neuroimaging data. Functional magnetic resonance imaging (fMRI) data were obtained from 22 individuals (12 females) while listening to music (joy, fear, or neutral music). ECM results showed that agreeableness scores correlated with centrality values in the dorsolateral prefrontal cortex, the anterior cingulate cortex, and the ventral striatum (nucleus accumbens). Individuals with higher E κ values (indexing higher tender emotionality) showed higher centrality values in the subiculum of the right hippocampal formation. Structural MRI data from an independent sample of 59 individuals (34 females) showed that neuroticism scores correlated with volume of the left amygdaloid complex. In addition, individuals with higher E κ showed larger gray matter volume in the same portion of the subiculum in which individuals with higher E κ showed higher centrality values. Our results highlight a role of the amygdala in neuroticism. Moreover, they indicate that a cardiac signature related to emotionality (E κ) correlates with both function (increased network centrality) and structure (grey matter volume) of the subiculum of the hippocampal formation, suggesting a role of the hippocampal formation for

[Epidemiological study of dental and facial asymmetries in a sample of preschool subjects].

Science.gov (United States)

Vitale, Marina Consuelo; Barbieri, Federica; Ricotta, Riccardo; Arpesella, Marisa; Emanuelli, Maria Teresa

2015-01-01

to identify the typologies of facial and dental asymmetries in a sample of children aged between 3 and 6 years and to correlate these asymmetries with possible morphological and functional situations. cross-sectional observational study. sample of 95 subjects aged between 3 and 6 years. Clinical data were collected in 10 sessions conducted during school hours in April 2013 by a doctor of Dentistry at two preschools in the city of Sanremo (Liguria Region, Northern Italy) and a kindergarten in the city of Pavia (Lombardy Region, Northern Italy). To collect the data, a weighted clinical questionnaire was used. presence and type of bad habit, type of breathing, presence and type of facial asymmetry, dental formula, presence of diastema, presence and type of occlusal asymmetries, presence and type of dental malocclusions. analysed sample consisted of 53.7% (51/95) of males and 46.3 % (44/95) females; the mean age was 4.3 ± 0.9 years. Most frequent facial asymmetry is orbits asymmetry (35%, 33/95); dental malocclusions are detected in 70%(67/95) of cases. High percentage of subjects (69.5%, 66/95) presents displacement between superior dental midline (SDM) and inferior dental midline (IDM). Several statistically significant associations are observed: in particular, asymmetry of molar ratios is linked to asymmetry of the cheekbones and displacement of the SDM; facial midline has statistical association with asymmetry of the cheekbones (p habits observed and the close correlation between: the presence of dental malocclusions and the presence of compromising habits, the presence of dental malocclusions and the presence of oral breathing.

Validity studies among hierarchical methods of cluster analysis using cophenetic correlation coefficient

International Nuclear Information System (INIS)

Carvalho, Priscilla R.; Munita, Casimiro S.; Lapolli, André L.

2017-01-01

The literature presents many methods for partitioning of data base, and is difficult choose which is the most suitable, since the various combinations of methods based on different measures of dissimilarity can lead to different patterns of grouping and false interpretations. Nevertheless, little effort has been expended in evaluating these methods empirically using an archaeological data base. In this way, the objective of this work is make a comparative study of the different cluster analysis methods and identify which is the most appropriate. For this, the study was carried out using a data base of the Archaeometric Studies Group from IPEN-CNEN/SP, in which 45 samples of ceramic fragments from three archaeological sites were analyzed by instrumental neutron activation analysis (INAA) which were determinate the mass fraction of 13 elements (As, Ce, Cr, Eu, Fe, Hf, La, Na, Nd, Sc, Sm, Th, U). The methods used for this study were: single linkage, complete linkage, average linkage, centroid and Ward. The validation was done using the cophenetic correlation coefficient and comparing these values the average linkage method obtained better results. A script of the statistical program R with some functions was created to obtain the cophenetic correlation. By means of these values was possible to choose the most appropriate method to be used in the data base. (author)

Validity studies among hierarchical methods of cluster analysis using cophenetic correlation coefficient

Energy Technology Data Exchange (ETDEWEB)

Carvalho, Priscilla R.; Munita, Casimiro S.; Lapolli, André L., E-mail: prii.ramos@gmail.com, E-mail: camunita@ipen.br, E-mail: alapolli@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

2017-07-01

The literature presents many methods for partitioning of data base, and is difficult choose which is the most suitable, since the various combinations of methods based on different measures of dissimilarity can lead to different patterns of grouping and false interpretations. Nevertheless, little effort has been expended in evaluating these methods empirically using an archaeological data base. In this way, the objective of this work is make a comparative study of the different cluster analysis methods and identify which is the most appropriate. For this, the study was carried out using a data base of the Archaeometric Studies Group from IPEN-CNEN/SP, in which 45 samples of ceramic fragments from three archaeological sites were analyzed by instrumental neutron activation analysis (INAA) which were determinate the mass fraction of 13 elements (As, Ce, Cr, Eu, Fe, Hf, La, Na, Nd, Sc, Sm, Th, U). The methods used for this study were: single linkage, complete linkage, average linkage, centroid and Ward. The validation was done using the cophenetic correlation coefficient and comparing these values the average linkage method obtained better results. A script of the statistical program R with some functions was created to obtain the cophenetic correlation. By means of these values was possible to choose the most appropriate method to be used in the data base. (author)

The UCLA hadronization model and Pt correlation study at √s = 29 GeV

International Nuclear Information System (INIS)

Chun, Sebong.

1989-01-01

With only longitudinal phase space, a linear confining quark potential, and Clebsch-Gordon coefficients, the authors demonstrate remarkable agreement with a large body of data. This involves only two parameters of a modified Lund symmetric fragmentation function a, b and three coherent lengths: the number of hadrons over which the transverse momentum P t is required to be compensated, the degree of the spin correlation between a diquark and its partner anti-diquark in baryon and anti-baryon production, and the degree of suppression of successive mesons created between a baryon and anti-baryon (which comes from the uncertainty principle). These coherent lengths have a common fundamental characteristic, namely, the propagation length of information along the chain of produced hadrons. As a separate effort to probe the propagation length of P t , we studied the correlations in momentum transverse to the event jet-axis for neighboring particles close in rapidity, which reflect the tendency of back-to-back production of the hadron pairs. He found indications of interesting correlations, but that a larger data sample is needed for definitive understanding of the area

Correlation between glucose concentrations in serum, plasma, and whole blood measured by a point-of-care glucometer and serum glucose concentration measured by an automated biochemical analyzer for canine and feline blood samples.

Science.gov (United States)

Tauk, Barbara S; Drobatz, Kenneth J; Wallace, Koranda A; Hess, Rebecka S

2015-06-15

To investigate the correlation between glucose concentrations in serum, plasma, and whole blood measured by a point-of-care glucometer (POCG) and serum glucose concentration measured by a biochemical analyzer. Prospective clinical study. 96 blood samples from 80 dogs and 90 blood samples from 65 cats. Serum, plasma, and whole blood were obtained from each blood sample. The glucose concentrations in serum, plasma, and whole blood measured by a POCG were compared with the serum glucose concentration measured by a biochemical analyzer by use of the Lin concordance correlation coefficient (ρc) and Bland-Altman plots. For both canine and feline samples, glucose concentrations in serum and plasma measured by the POCG were more strongly correlated with the serum glucose concentration measured by the biochemical analyzer (ρc, 0.98 for both canine serum and plasma; ρc, 0.99 for both feline serum and plasma) than was that in whole blood (ρc, 0.62 for canine samples; ρc, 0.90 for feline samples). The mean difference between the glucose concentrations determined by the biochemical analyzer and the POCG in serum, plasma, and whole blood was 0.4, 0.3, and 31 mg/dL, respectively, for canine samples and 7, 6, and 32 mg/dL, respectively, for feline samples. Results indicated that use of a POCG to measure glucose concentrations in serum or plasma may increase the accuracy and reliability of diagnostic and treatment decisions associated with glucose homeostasis disorders in dogs and cats.

Finite sample properties of power-law cross-correlations estimators

Czech Academy of Sciences Publication Activity Database

Krištoufek, Ladislav

2015-01-01

Roč. 419, č. 1 (2015), s. 513-525 ISSN 0378-4371 R&D Projects: GA ČR(CZ) GP14-11402P Keywords : power-law cross-correlations * long - term memory * econophysics Subject RIV: AH - Economics Impact factor: 1.785, year: 2015 http://library.utia.cas.cz/separaty/2014/E/kristoufek-0433530.pdf

A study of correlations in the stock market

Science.gov (United States)

Sharma, Chandradew; Banerjee, Kinjal

2015-08-01

We study the various sectors of the Bombay Stock Exchange (BSE) for a period of 8 years from April 2006 to March 2014. Using the data of daily returns of a period of eight years we make a direct model free analysis of the pattern of the sectorial indices movement and the correlations among them. Our analysis shows significant auto correlation among the individual sectors and also strong cross-correlation among sectors. We also find that auto correlations in some of the sectors persist in time. This is a very significant result and has not been reported so far in Indian context. These findings will be very useful in model building for prediction of price movement of equities, derivatives and portfolio management. We show that the Random Walk Hypothesis is not applicable in modeling the Indian market and mean-variance-skewness-kurtosis based portfolio optimization might be required. We also find that almost all sectors are highly correlated during large fluctuation periods and have only moderate correlation during normal periods.

Statistical analysis of latent generalized correlation matrix estimation in transelliptical distribution.

Science.gov (United States)

Han, Fang; Liu, Han

2017-02-01

Correlation matrix plays a key role in many multivariate methods (e.g., graphical model estimation and factor analysis). The current state-of-the-art in estimating large correlation matrices focuses on the use of Pearson's sample correlation matrix. Although Pearson's sample correlation matrix enjoys various good properties under Gaussian models, its not an effective estimator when facing heavy-tail distributions with possible outliers. As a robust alternative, Han and Liu (2013b) advocated the use of a transformed version of the Kendall's tau sample correlation matrix in estimating high dimensional latent generalized correlation matrix under the transelliptical distribution family (or elliptical copula). The transelliptical family assumes that after unspecified marginal monotone transformations, the data follow an elliptical distribution. In this paper, we study the theoretical properties of the Kendall's tau sample correlation matrix and its transformed version proposed in Han and Liu (2013b) for estimating the population Kendall's tau correlation matrix and the latent Pearson's correlation matrix under both spectral and restricted spectral norms. With regard to the spectral norm, we highlight the role of "effective rank" in quantifying the rate of convergence. With regard to the restricted spectral norm, we for the first time present a "sign subgaussian condition" which is sufficient to guarantee that the rank-based correlation matrix estimator attains the optimal rate of convergence. In both cases, we do not need any moment condition.

Parents' occupation as correlate of students' career aspiration in ...

African Journals Online (AJOL)

This study investigated the relationship between parents' occupation and students' career aspiration in public secondary schools in Esan West Local Government Area of Edo State. The correlational research design was adopted for the study. A sample of 320 students was drawn for by simple random sampling technique ...

Treatability study sample exemption: update

International Nuclear Information System (INIS)

1997-01-01

This document is a RCRA Information Brief intended to update the information in the 1991 Small-Scale Treatability Study Information Brief, and to address questions about the waste and treatability study sample exemptions that have arisen since References 3 and 5 were published

[Saarland Growth Study: sampling design].

Science.gov (United States)

Danker-Hopfe, H; Zabransky, S

2000-01-01

The use of reference data to evaluate the physical development of children and adolescents is part of the daily routine in the paediatric ambulance. The construction of such reference data is based on the collection of extensive reference data. There are different kinds of reference data: cross sectional references, which are based on data collected from a big representative cross-sectional sample of the population, longitudinal references, which are based on follow-up surveys of usually smaller samples of individuals from birth to maturity, and mixed longitudinal references, which are a combination of longitudinal and cross-sectional reference data. The advantages and disadvantages of the different methods of data collection and the resulting reference data are discussed. The Saarland Growth Study was conducted for several reasons: growth processes are subject to secular changes, there are no specific reference data for children and adolescents from this part of the country and the growth charts in use in the paediatric praxis are possibly not appropriate any more. Therefore, the Saarland Growth Study served two purposes a) to create actual regional reference data and b) to create a database for future studies on secular trends in growth processes of children and adolescents from Saarland. The present contribution focusses on general remarks on the sampling design of (cross-sectional) growth surveys and its inferences for the design of the present study.

Positronium in metal-oxide powders studied with age. The age-momentum correlation technique

International Nuclear Information System (INIS)

Waeyenberge, B. van; Dauve, Ch.

2001-01-01

For the first time positronium is investigated in the fine powders of MgO and Al 2 O 3 using age-momentum correlation technique based on a relativistic positron beam. The application of this technique for investigating the interaction of positronium with the grain surfaces is discussed and compared with other techniques. The previously reported interaction of the positronium with paramagnetic centers is further studied. A qualitative interpretation of the spectra is given. In the Al 2 O 3 samples we found some unexpected behaviour of the conversion quenching of ortho-positronium at irradiation induced paramagnetic surface defect. (author)

Childhood overweight and social correlates among school-going ...

African Journals Online (AJOL)

The purpose of this study was to investigate overweight and obesity and social correlates among school children in Dominica and Jamaica. The total sample included 3265 adolescents aged primarily 13 to 16 years from nationally representative samples from two Caribbean countries. Bivariate and multivariable analyses ...

The Feasibility Study for Multigeometries Identification of Uranium Components Using PCA-LSSVM Based on Correlation Measurements

Directory of Open Access Journals (Sweden)

Mi Zhou

2018-01-01

Full Text Available The geometry of uranium components is one of the key characteristics and strictly confidential. The geometry identification of metal uranium components was studied using 252Cf source-driven correlation measurement method. For the 3 uranium samples with the same mass and enrichment, there are subtle differences in neutron signals. Even worse, the correlation functions were disturbed by scatter neutrons and include “accidental” coincidence, which is not conductive to the geometry identification. In this paper, we proposed an identification method combining principal component analysis and least-square support vector machine (PCA-LSSVM. The results based on PCA-LSSVM showed that the training precision was 100% and the test precision was 95.83% of the identification model. The total precision of the identification model was 98.41%, which indicated that the identification model was an effective way to identify the geometry properties with the correlation functions.

Experimentation and correlates of electronic nicotine delivery system (electronic cigarettes) among university students - A cross sectional study.

Science.gov (United States)

Awan, K H

2016-04-01

E-cigarettes are becoming popular among youth as safe nicotine delivery systems. Many have expressed concern, however, that e-cigarettes may serve as a gateway to future smoking, given their low perceived risk, or that their use may prevent regular smokers from quitting by maintaining their nicotine addiction. The aim of this study was to assess experimentation with and correlates of e-cigarette use among university students. A cross-sectional study was carried out among 480 university students from four faculties at a university in Riyadh in August-October 2014. A modified version of the World Health Organization's Global Adult Tobacco Survey was used, and multinomial logistic regression was carried out to assess correlations with e-cigarette variables in the whole study sample and among smokers. Almost all students, including the majority of ex-smokers (96.3%) and smokers (94.4%), reported having heard about e-cigarettes. In addition, about one-quarter of the sample (54.2% of smokers, 24.7% of ex-smokers, 6% of never smokers) had experimented with e-cigarettes at least once during their lifetime. Curiosity and peer influence were reported as the main reasons for the use of e-cigarettes. Factors found to be correlated significantly with e-cigarette use were male gender, being a traditional cigarette smoker, having friends who have tried e-cigarettes, and having a strong belief that e-cigarettes could aid smoking cessation. E-cigarettes are popular among Saudi youth, especially among smokers and ex-smokers. Well-designed health education programs and regulatory interventions are required to address this issue.

Environmental Pollution by Benzene and PM10 and Clinical Manifestations of Systemic Sclerosis: A Correlation Study.

Science.gov (United States)

Borghini, Alice; Poscia, Andrea; Bosello, Silvia; Teleman, Adele Anna; Bocci, Mario; Iodice, Lanfranco; Ferraccioli, Gianfranco; La Milìa, Daniele Ignazio; Moscato, Umberto

2017-10-26

Atmospheric air pollution has been associated with a range of adverse health effects. The environment plays a causative role in the development of Systemic Sclerosis (SSc). The aim of the present study is to explore the association between particulate (PM 10 ) and benzene (B) exposure in Italian patients with systemic sclerosis and their clinical characteristics of the disease. A correlation study was conducted by enrolling 88 patients who suffer from SSc at the Fondazione Policlinico "A. Gemelli" in Rome (Italy) in the period from January 2013 to January 2014. The average mean concentrations of B (in 11 monitoring sites) and PM 10 (in 14 sites) were calculated using data from the Regional Environmental Protection Agency's monitoring stations located throughout the Lazio region (Italy) and then correlated with the clinical characteristics of the SSc patients. Of the study sample, 92.5% were female. The mean age was 55 ± 12.9 years old and the mean disease duration from the onset of Raynaud's phenomenon was 13.0 ± 9.4 years. The Spearman's correlation showed that concentrations of B correlate directly with the skin score (R = 0.3; p ≤ 0.05) and inversely with Diffusing Lung Carbon Monoxide (DLCO) results (R = -0.36; p = 0.04). This study suggests a possible role of B in the development of diffuse skin disease and in a worse progression of the lung manifestations of SSc.

Correlates of interpersonal dependency and detachment in an adolescent inpatient sample.

Science.gov (United States)

Haggerty, Greg; Siefert, Caleb J; Bornstein, Robert F; Sinclair, Samuel Justin; Blais, Mark A; Zodan, Jennifer; Rao, Nyapati

2015-01-01

Interpersonal dependency has been linked to psychological distress, depression, help seeking, treatment compliance, and sensitivity to interpersonal cues in adult samples. However, there is a dearth of research focusing on dependency in child and adolescent samples. The current study examined the construct validity of a measure of interpersonal dependency. The authors investigated how interpersonal dependency and detachment relate to behavioral problems, subjective well-being, interpersonal problems, and global symptom severity in adolescent inpatients. Destructive overdependence (DO) and dysfunctional detachment (DD) were positively related to interpersonal distress, behavioral problems, and symptom severity and negatively related to psychological health and well-being. Healthy dependency (HD) was associated with fewer behavioral problems and less symptom severity and positively related to subjective well-being. The clinical implications of these findings are discussed.

Correlates of current transactional sex among a sample of female exotic dancers in Baltimore, MD.

Science.gov (United States)

Reuben, Jacqueline; Serio-Chapman, Chris; Welsh, Christopher; Matens, Richard; Sherman, Susan G

2011-04-01

Transactional sex work, broadly defined as the exchange of money, drugs, or goods for sexual services, occurs in a wide range of environments. There is a large body of research characterizing the risks and harms associated with street- and venue-based sex work, but there is a dearth of research characterizing the risk associated with the environment of exotic dance clubs. The current study aimed to: (1) characterize the nature of female exotic dancers' sex- and drug-related risk behaviors, (2) to examine the role of the club environment in these behaviors, and (3) to examine correlates of currently exchanging sex. From June 2008 to February 2009, we conducted a cross-sectional study among women who were aged 18 years or older and reported exotic dancing within the past 3 months (n = 98). The survey ascertained socio-demographic characteristics, personal health, medical history, sexual practices, drug use, and employment at clubs on the block. Bivariate and multivariate Poisson regression with robust variance was used to identify correlates of current sex exchange. Participants were a median of 24 years old, and were 58% white; 43% had not completed high school. Seventy-four percent reported ever having been arrested. Twenty-six percent reported having injected heroin and 29% reported having smoked crack in the past 3 months. Fifty-seven percent reported using drugs in the club in the past 3 months. Sixty-one percent had ever engaged in transactional sex, and 67% of those did so for the first time after beginning to dance. Forty-three percent reported selling any sex in the club in the past 3 months. In multiple Poisson regression, factors associated with current sex exchange included: race, ever having been arrested, and using drugs in the club. High levels of both drug use and transactional sex among this sample of exotic dancers were reported. These findings indicate that there are a number of drug- and sex-related harms faced by exotic dancers in strip clubs

Position-dependent correlation function from the SDSS-III Baryon Oscillation Spectroscopic Survey Data Release 10 CMASS sample

International Nuclear Information System (INIS)

Chiang, Chi-Ting; Wagner, Christian; Sánchez, Ariel G.; Schmidt, Fabian; Komatsu, Eiichiro

2015-01-01

We report on the first measurement of the three-point function with the position-dependent correlation function from the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 10 CMASS sample. This new observable measures the correlation between two-point functions of galaxy pairs within different subvolumes, ξ-circumflex (ř,ř L ), where ř L is the location of a subvolume, and the corresponding mean overdensities, δ-bar (ř L ). This correlation, which we call the 'integrated three-point function', iζ(r)≡(ξ-circumflex (ř,ř L )δ-bar (ř L )), measures a three-point function of two short- and one long-wavelength modes, and is generated by nonlinear gravitational evolution and possibly also by the physics of inflation. The iζ(r) measured from the BOSS data lies within the scatter of those from the mock galaxy catalogs in redshift space, yielding a ten-percent-level determination of the amplitude of iζ(r). The tree-level perturbation theory in redshift space predicts how this amplitude depends on the linear and quadratic nonlinear galaxy bias parameters (b 1 and b 2 ), as well as on the amplitude and linear growth rate of matter fluctuations (σ 8 and f). Combining iζ(r) with the constraints on b 1σ 8 and fσ 8 from the global two-point correlation function and that on σ 8 from the weak lensing signal of BOSS galaxies, we measure b 2 =0.41±0.41 (68% C.L.) assuming standard perturbation theory at the tree level and the local bias model

Molecular photoionization studies of nucleobases and correlated systems

Energy Technology Data Exchange (ETDEWEB)

Poliakoff, Erwin D. [Louisiana State Univ., Baton Rouge, LA (United States)

2015-03-11

We proposed molecular photoionization studies in order to probe correlated events in fundamental scattering phenomena. In particular, we suggested that joint theoretical-experimental studies would provide a window into the microscopic aspects that are of central importance in AMO and chemical physics generally, and would generate useful data for wide array of important DOE topics, such as ultrafast dynamics, high harmonic generation, and probes of nonadiabatic processes. The unifying theme is that correlations between electron scattering dynamics and molecular geometry highlight inherently molecular aspects of the photoelectron behavior.

Sampling pig farms at the abattoir in a cross-sectional study - Evaluation of a sampling method.

Science.gov (United States)

Birkegård, Anna Camilla; Halasa, Tariq; Toft, Nils

2017-09-15

A cross-sectional study design is relatively inexpensive, fast and easy to conduct when compared to other study designs. Careful planning is essential to obtaining a representative sample of the population, and the recommended approach is to use simple random sampling from an exhaustive list of units in the target population. This approach is rarely feasible in practice, and other sampling procedures must often be adopted. For example, when slaughter pigs are the target population, sampling the pigs on the slaughter line may be an alternative to on-site sampling at a list of farms. However, it is difficult to sample a large number of farms from an exact predefined list, due to the logistics and workflow of an abattoir. Therefore, it is necessary to have a systematic sampling procedure and to evaluate the obtained sample with respect to the study objective. We propose a method for 1) planning, 2) conducting, and 3) evaluating the representativeness and reproducibility of a cross-sectional study when simple random sampling is not possible. We used an example of a cross-sectional study with the aim of quantifying the association of antimicrobial resistance and antimicrobial consumption in Danish slaughter pigs. It was not possible to visit farms within the designated timeframe. Therefore, it was decided to use convenience sampling at the abattoir. Our approach was carried out in three steps: 1) planning: using data from meat inspection to plan at which abattoirs and how many farms to sample; 2) conducting: sampling was carried out at five abattoirs; 3) evaluation: representativeness was evaluated by comparing sampled and non-sampled farms, and the reproducibility of the study was assessed through simulated sampling based on meat inspection data from the period where the actual data collection was carried out. In the cross-sectional study samples were taken from 681 Danish pig farms, during five weeks from February to March 2015. The evaluation showed that the sampling

Phthalate metabolites in urine samples from Danish children and correlations with phthalates in dust samples from their homes and daycare centers

DEFF Research Database (Denmark)

Langer, S.; Bekö, Gabriel; Weschler, Charles J.

2013-01-01

Around the world humans use products that contain phthalates, and human exposure to certain of these phthalates has been associated with various adverse health effects. The aim of the present study has been to determine the concentrations of the metabolites of diethyl phthalate (DEP), di......(n-butyl) phthalate (DnBP), di(iso-butyl) phthalate (DiBP), butyl benzyl phthalate (BBzP) and di(2-ethylhexyl) phthalate (DEHP) in urine samples from 441 Danish children (3–6 years old). These children were subjects in the Danish Indoor Environment and Children's Health study. As part of each child's medical...... examination, a sample from his or her first morning urination was collected. These samples were subsequently analyzed for metabolites of the targeted phthalates. The measured concentrations of each metabolite were approximately log-normally distributed, and the metabolite concentrations significantly...

A study of highly correlated classical and quantum fluids

International Nuclear Information System (INIS)

Clements, B.E.

1988-01-01

We have determined, by molecular dynamics simulation, the l = 0, 2, 4, and 6 Legendre coefficients of the static pair-pair correlation function Q(r,r'), the dynamic pair-pair correlation function Q(r,r';t) and the dynamic four point correlation function S 4 (k, -k,q, -q;t). The interaction potential was taken to be Lennard-Jones. The simulation was carried out at two different values of density and temperature; one coinciding with that of liquid argon near its triple point and the other coinciding with high density argon at room temperature. We argue that an important contribution to the pair-pair correlation function comes from the thee-body correlations. We find that the Legendre coefficients of Q(r,r') provide strong evidence that, upon freezing, the resulting crystalline structure will be a close-packed structure. A study of dynamical fluctuations characterized by Legendre coefficients of the dynamic pair-pair correlation function support this assertion. Finally, we provide a discussion on a decoupling scheme, used in the literature, to approximate the static and dynamic four point correlation function. A variational calculation with the Penrose-Reatto-Chester-Jastrow density matrix is used to study the finite temperature properties of Bose quantum fluids. This analysis provides a systematic method for adding correction terms to the density matrix approach of Campbell, Ristig, Kurten and Senger. We find that the excitation spectrum for the elementary excitations has the proper temperature dependence in contrast to earlier calculations

Correlation of morphological variants of the soft palate and Need's ratio in normal individuals: A digital cephalometric study

International Nuclear Information System (INIS)

Verma, Pradhuman; Verma, Kanika Gupta; Sachdeva, Suresh K; Juneja, Suruchi; Kumaraswam; Kikkeri Lakshminarayana; Basavaraju, Suman

2014-01-01

The present study was aimed to investigate the variation of soft palate morphology in different age and gender groups. The correlations of radiographic velar length (VL), velar width (VW), pharyngeal depth (PD), and Need's ratio with soft palate variants were also studied in the North Indian subpopulation. The study sample consisted of 300 subjects aged between 15 and 45 (mean: 31.32) years. The velar morphology on lateral cephalograms was examined and grouped into six types. The results obtained were subjected to a statistical analysis to find the correlation between variants of the soft palate with gender and different age groups. The most frequent type of soft palate was leaf shaped (48.7%), and the least common was crook shaped (3.0%) among both the genders and various age groups, showing a significant correlation. The mean VL, VW, and PD values were significantly higher in males and significantly correlated with the types of soft palate. A significant correlation was observed between the mean VL, VW, PD, and Need's ratio with various age groups, showing an inconsistent pattern with an increase in age. The types of soft palate, gender, and Need's ratio were also significantly correlated, with an overall higher mean value of the Need's ratio among female subjects and the S-shaped soft palate. The knowledge of a varied spectrum of velar morphology and the variants of the soft palate help in a better understanding of the velopharyngeal closure and craniofacial anomalies.

Study on the correlation of MLCK and FAP expression with uterine fibroid cell proliferation and invasion

Directory of Open Access Journals (Sweden)

Wei Lin1

2017-06-01

Full Text Available Objective: To study the correlation of myosin light chain kinase (MLCK and fibroblast activation protein (FAP expression with uterine fibroid cell proliferation and invasion. Methods: Uterine fibroids samples and normal uterine muscle samples next to fibroids that were surgically removed in Wuhan Red Cross Hospital between May 2014 and January 2017 were chosen, fluorescence quantitative PCR kits were used to deterct MLCK and FAP mRNA expression, and enzyme-linked immunosorbent assay kits were used to determine proliferation and invasion gene protein expression. Results: MLCK and FAP mRNA expression in uterine fibroids samples were significantly higher than those in normal uterine muscle samples, and Survivin, Livin, Bcl-2, Snail, N-cadherin and MMP2 protein expression were significantly higher than those in normal uterine muscle samples; Survivin, Livin, Bcl-2, Snail, N-cadherin and MMP2 protein expression in uterine fibroids samples with high MLCK and FAP expression were significantly higher than those in uterine fibroids samples with low MLCK and FAP expression. Conclusion: Highly expressed MLCK and FAP in uterine fibroids can promote the proliferation and invasion of uterine fibroids.

Smoking-related correlates of psychomotor restlessness and agitation in a community sample of daily cigarette smokers.

Science.gov (United States)

Wong, Jordan A; Leventhal, Adam M

2015-03-01

Psychomotor restlessness and agitation (PMA) is a putatively important, yet understudied, psychopathologic correlate of smoking. The scant smoking research on PMA previously conducted has been narrow in scope and conducted among psychiatric patients. To examine the generalizability and relevance of PMA to smoking, this cross-sectional study investigated associations between PMA and a variety of smoking processes in a community sample. Participants in this study were non-treatment-seeking smokers (N = 254, ≥10 cig/day, M age = 44 years) from the community without an active mood disorder. At baseline, they completed a PMA symptom checklist, a composite depressive symptom index, and a battery of smoking questionnaires. Linear regression models adjusting for depressive symptoms and demographics indicated that PMA level was positively associated with severity of nicotine withdrawal symptoms during prior quit attempts (β = .18, p smoke for negative reinforcement (β = .14, p smoking expectancies for negative reinforcement (β = .17, p smoking chronicity, frequency, or dependence severity. Smokers with elevated PMA appear to experience greater smoking-induced affect modulation and nicotine withdrawal than the average smoker, regardless of other depressive symptoms. Given that PMA differentiates a qualitatively unique profile of smoking characteristics, PMA warrants consideration in tobacco addiction research and practice. © American Academy of Addiction Psychiatry.

Effect of static scatterers in laser speckle contrast imaging: an experimental study on correlation and contrast

Science.gov (United States)

Vaz, Pedro G.; Humeau-Heurtier, Anne; Figueiras, Edite; Correia, Carlos; Cardoso, João

2018-01-01

Laser speckle contrast imaging (LSCI) is a non-invasive microvascular blood flow assessment technique with good temporal and spatial resolution. Most LSCI systems, including commercial devices, can perform only qualitative blood flow evaluation, which is a major limitation of this technique. There are several factors that prevent the utilization of LSCI as a quantitative technique. Among these factors, we can highlight the effect of static scatterers. The goal of this work was to study the influence of differences in static and dynamic scatterer concentration on laser speckle correlation and contrast. In order to achieve this, a laser speckle prototype was developed and tested using an optical phantom with various concentrations of static and dynamic scatterers. It was found that the laser speckle correlation could be used to estimate the relative concentration of static/dynamic scatterers within a sample. Moreover, the speckle correlation proved to be independent of the dynamic scatterer velocity, which is a fundamental characteristic to be used in contrast correction.

Sample selection and taste correlation in discrete choice transport modelling

DEFF Research Database (Denmark)

Mabit, Stefan Lindhard

2008-01-01

explain counterintuitive results in value of travel time estimation. However, the results also point at the difficulty of finding suitable instruments for the selection mechanism. Taste heterogeneity is another important aspect of discrete choice modelling. Mixed logit models are designed to capture...... the question for a broader class of models. It is shown that the original result may be somewhat generalised. Another question investigated is whether mode choice operates as a self-selection mechanism in the estimation of the value of travel time. The results show that self-selection can at least partly...... of taste correlation in willingness-to-pay estimation are presented. The first contribution addresses how to incorporate taste correlation in the estimation of the value of travel time for public transport. Given a limited dataset the approach taken is to use theory on the value of travel time as guidance...

Why do measures of normal and disordered personality correlate? A study of genetic comorbidity.

Science.gov (United States)

Jang, K L; Livesley, W J

1999-01-01

The genetic and environmental correlations between measures of normal (NEO-FFI) and abnormal personality (Dimensional Assessment of Personality Pathology: DAPP-BQ) were estimated in a sample of 545 volunteer general population twin pairs (269 monozygotic and 276 dizygotic pairs). The largest genetic correlations were observed between the 18 DAPP-BQ dimensions and NEO-FFI neuroticism (range = .05 to .81; median = .48), extraversion (range = -.65 to .33; median = -.28), agreeableness (range = -.65 to .00; median = -.38), and conscientiousness (range = -.76 to .52; median = -.31). The smallest genetic correlations were found between the DAPP-BQ dimensions and NEO-FFI openness (range = -.17 to .20; median = -.04). The environmental correlations are lower in magnitude but show the same pattern of correlations between DAPP-BQ and NEO-FFI scales. These results indicate that these two scales share a common broad-based genetic architecture, whereas the environmental influences show greater scale specificity.

Biological Sampling Variability Study

Energy Technology Data Exchange (ETDEWEB)

Amidan, Brett G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hutchison, Janine R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-11-08

There are many sources of variability that exist in the sample collection and analysis process. This paper addresses many, but not all, sources of variability. The main focus of this paper was to better understand and estimate variability due to differences between samplers. Variability between days was also studied, as well as random variability within each sampler. Experiments were performed using multiple surface materials (ceramic and stainless steel), multiple contaminant concentrations (10 spores and 100 spores), and with and without the presence of interfering material. All testing was done with sponge sticks using 10-inch by 10-inch coupons. Bacillus atrophaeus was used as the BA surrogate. Spores were deposited using wet deposition. Grime was coated on the coupons which were planned to include the interfering material (Section 3.3). Samples were prepared and analyzed at PNNL using CDC protocol (Section 3.4) and then cultured and counted. Five samplers were trained so that samples were taken using the same protocol. Each sampler randomly sampled eight coupons each day, four coupons with 10 spores deposited and four coupons with 100 spores deposited. Each day consisted of one material being tested. The clean samples (no interfering materials) were run first, followed by the dirty samples (coated with interfering material). There was a significant difference in recovery efficiency between the coupons with 10 spores deposited (mean of 48.9%) and those with 100 spores deposited (mean of 59.8%). There was no general significant difference between the clean and dirty (containing interfering material) coupons or between the two surface materials; however, there was a significant interaction between concentration amount and presence of interfering material. The recovery efficiency was close to the same for coupons with 10 spores deposited, but for the coupons with 100 spores deposited, the recovery efficiency for the dirty samples was significantly larger (65

Effect of dissolved organic matter on pre-equilibrium passive sampling: A predictive QSAR modeling study.

Science.gov (United States)

Lin, Wei; Jiang, Ruifen; Shen, Yong; Xiong, Yaxin; Hu, Sizi; Xu, Jianqiao; Ouyang, Gangfeng

2018-04-13

Pre-equilibrium passive sampling is a simple and promising technique for studying sampling kinetics, which is crucial to determine the distribution, transfer and fate of hydrophobic organic compounds (HOCs) in environmental water and organisms. Environmental water samples contain complex matrices that complicate the traditional calibration process for obtaining the accurate rate constants. This study proposed a QSAR model to predict the sampling rate constants of HOCs (polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and pesticides) in aqueous systems containing complex matrices. A homemade flow-through system was established to simulate an actual aqueous environment containing dissolved organic matter (DOM) i.e. humic acid (HA) and (2-Hydroxypropyl)-β-cyclodextrin (β-HPCD)), and to obtain the experimental rate constants. Then, a quantitative structure-activity relationship (QSAR) model using Genetic Algorithm-Multiple Linear Regression (GA-MLR) was found to correlate the experimental rate constants to the system state including physicochemical parameters of the HOCs and DOM which were calculated and selected as descriptors by Density Functional Theory (DFT) and Chem 3D. The experimental results showed that the rate constants significantly increased as the concentration of DOM increased, and the enhancement factors of 70-fold and 34-fold were observed for the HOCs in HA and β-HPCD, respectively. The established QSAR model was validated as credible (R Adj. 2 =0.862) and predictable (Q 2 =0.835) in estimating the rate constants of HOCs for complex aqueous sampling, and a probable mechanism was developed by comparison to the reported theoretical study. The present study established a QSAR model of passive sampling rate constants and calibrated the effect of DOM on the sampling kinetics. Copyright © 2018 Elsevier B.V. All rights reserved.

Measuring and testing dependence by correlation of distances

OpenAIRE

Székely, Gábor J.; Rizzo, Maria L.; Bakirov, Nail K.

2007-01-01

Distance correlation is a new measure of dependence between random vectors. Distance covariance and distance correlation are analogous to product-moment covariance and correlation, but unlike the classical definition of correlation, distance correlation is zero only if the random vectors are independent. The empirical distance dependence measures are based on certain Euclidean distances between sample elements rather than sample moments, yet have a compact representation analogous to the clas...

The interplay between post-critical beliefs and anxiety: an exploratory study in a Polish sample.

Science.gov (United States)

Śliwak, Jacek; Zarzycka, Beata

2012-06-01

The present research investigates the relationship between anxiety and the religiosity dimensions that Wulff (Psychology of religion: classic and contemporary views, Wiley, New York, 1991; Psychology of religion. Classic and contemporary views, Wiley, New York, 1997; Psychologia religii. Klasyczna i współczesna, Wydawnictwo Szkolne i Pedagogiczne, Warszawa, 1999) described as Exclusion vs. Inclusion of Transcendence and Literal vs. Symbolic. The researchers used the Post-Critical Belief scale (Hutsebaut in J Empir Theol 9(2):48-66, 1996; J Empir Theol 10(1):39-54, 1997) to measure Wulff's religiosity dimensions and the IPAT scale (Krug et al. 1967) to measure anxiety. Results from an adult sample (N = 83) suggest that three dimensions show significant relations with anxiety. Orthodoxy correlated negatively with suspiciousness (L) and positively with guilt proneness (O) factor-in the whole sample. Among women, Historical Relativism negatively correlated with suspiciousness (L), lack of integration (Q3), general anxiety and covert anxiety. Among men, Historical Relativism positively correlated with tension (Q4) and emotional instability (C), general anxiety, covert anxiety and overt anxiety. External Critique was correlated with suspiciousness (L) by men.

Monolith Chromatography as Sample Preparation Step in Virome Studies of Water Samples.

Science.gov (United States)

Gutiérrez-Aguirre, Ion; Kutnjak, Denis; Rački, Nejc; Rupar, Matevž; Ravnikar, Maja

2018-01-01

Viruses exist in aquatic media and many of them use this media as transmission route. Next-generation sequencing (NGS) technologies have opened new doors in virus research, allowing also to reveal a hidden diversity of viral species in aquatic environments. Not surprisingly, many of the newly discovered viruses are found in environmental fresh and marine waters. One of the problems in virome research can be the low amount of viral nucleic acids present in the sample in contrast to the background ones (host, eukaryotic, prokaryotic, environmental). Therefore, virus enrichment prior to NGS is necessary in many cases. In water samples, an added problem resides in the low concentration of viruses typically present in aquatic media. Different concentration strategies have been used to overcome such limitations. CIM monoliths are a new generation of chromatographic supports that due to their particular structural characteristics are very efficient in concentration and purification of viruses. In this chapter, we describe the use of CIM monolithic chromatography for sample preparation step in NGS studies targeting viruses in fresh or marine water. The step-by-step protocol will include a case study where CIM concentration was used to study the virome of a wastewater sample using NGS.

Study of Low-grade Chronic Inflammatory Markers in Men with Central Obesity: Cathepsin S was Correlated with Waist Circumference

Directory of Open Access Journals (Sweden)

Adriana Todingrante

2013-08-01

Full Text Available BACKGROUND: There is a prevalence increase of overweight and obesity in Indonesia. Central obesity can lead a variety of chronic diseases through the inflammatory process. There are some markers for low-grade chronic inflammatory, such as cathepsin S, high sensitivity C-reactive protein (hs-CRP, interleukin-1- beta (IL-1β. To our current interest that central obesity can lead to various chronic diseases through the inflammatory process, we conducted a study to investigate correlation of Cathepsin S, hs-CRP, IL-1β in men with central obesity. METHODS: A cross-sectional study was conducted. Seventy-eight selected subjects were examined to collect anthropometric data and prepared for sample collection. Collected samples were processed for the following biochemical analyses: fasting glucose, high density lipoprotein (HDL-cholesterol, triglyceride, serum glutamic oxaloacetic transaminase (SGOT, serum glutamate pyruvate transaminase (SGPT, cathepsin S, hs-CRP, and IL-1β. Data distribution and variable correlation were then statistically analyzed. RESULTS: There were significant correlations between waist circumference (WC and cathepsin S (p=0.030; r=0.214, hs-CRP and cathepsin S (p=0.007; r=0.276, triglyceride and IL-1β (p=0.019; r=-0.235, WC and systolic blood pressure (SBP (p=0.003; r=-0.312, WC and fasting glucose (p=0.000; r=0.380, WC and body mass index (BMI (p=0.000; r=0.708. CONCLUSIONS: Our study showed that cathepsin S was correlated with central obesity, suggesting that cathepsin S could be a potential inflammatory marker in central obesity in the future. KEYWORDS: obesity, inflammation, hs-CRP, cathepsin S, IL-1β, waist circumference.

Variable angle correlation spectroscopy

International Nuclear Information System (INIS)

Lee, Y.K.; Lawrence Berkeley Lab., CA

1994-05-01

In this dissertation, a novel nuclear magnetic resonance (NMR) technique, variable angle correlation spectroscopy (VACSY) is described and demonstrated with 13 C nuclei in rapidly rotating samples. These experiments focus on one of the basic problems in solid state NMR: how to extract the wealth of information contained in the anisotropic component of the NMR signal while still maintaining spectral resolution. Analysis of the anisotropic spectral patterns from poly-crystalline systems reveal information concerning molecular structure and dynamics, yet in all but the simplest of systems, the overlap of spectral patterns from chemically distinct sites renders the spectral analysis difficult if not impossible. One solution to this problem is to perform multi-dimensional experiments where the high-resolution, isotropic spectrum in one dimension is correlated with the anisotropic spectral patterns in the other dimensions. The VACSY technique incorporates the angle between the spinner axis and the static magnetic field as an experimental parameter that may be incremented during the course of the experiment to help correlate the isotropic and anisotropic components of the spectrum. The two-dimensional version of the VACSY experiments is used to extract the chemical shift anisotropy tensor values from multi-site organic molecules, study molecular dynamics in the intermediate time regime, and to examine the ordering properties of partially oriented samples. The VACSY technique is then extended to three-dimensional experiments to study slow molecular reorientations in a multi-site polymer system

Comparison of POCIS passive samplers vs. composite water sampling: A case study.

Science.gov (United States)

Criquet, Justine; Dumoulin, David; Howsam, Michael; Mondamert, Leslie; Goossens, Jean-François; Prygiel, Jean; Billon, Gabriel

2017-12-31

The relevance of Polar Organic Chemical Integrative Samplers (POCIS) was evaluated for the assessment of concentrations of 46 pesticides and 19 pharmaceuticals in a small, peri-urban river with multi-origin inputs. Throughout the period of POCIS deployment, 24h-average water samples were collected automatically, and showed the rapid temporal evolution of concentrations of several micropollutants, as well as permitting the calculation of average concentrations in the water phase for comparison with those estimated from POCIS passive samplers. In the daily water samples, cyproconazol, epoxyconazol and imidacloprid showed high temporal variations with concentrations ranging from under the limit of detection up to several hundreds of ngL -1 . Erythromycin, cyprofloxacin and iopromide also increased rapidly up to tens of ngL -1 within a few days. Conversely, atrazine, caffeine, diclofenac, and to a lesser extent carbamazepine and sucralose, were systematically present in the water samples and showed limited variation in concentrations. For most of the substances studied here, the passive samplers gave reliable average concentrations between the minimal and maximal daily concentrations during the time of deployment. For pesticides, a relatively good correlation was clearly established (R 2 =0.89) between the concentrations obtained by POCIS and those gained from average water samples. A slight underestimation of the concentration by POCIS can be attributed to inappropriate sampling rates extracted from the literature and for our system, and new values are proposed. Considering the all data set, 75% of the results indicate a relatively good agreement between the POCIS and the average water samples concentration (values of the ratio ranging between 0,33 and 3). Note further that this agreement between these concentrations remains valid considering different sampling rates extracted from the literature. Copyright © 2017 Elsevier B.V. All rights reserved.

Correlates of emotional congruence with children in sexual offenders against children: a test of theoretical models in an incarcerated sample.

Science.gov (United States)

McPhail, Ian V; Hermann, Chantal A; Fernandez, Yolanda M

2014-02-01

Emotional congruence with children is a psychological construct theoretically involved in the etiology and maintenance of sexual offending against children. Research conducted to date has not examined the relationship between emotional congruence with children and other psychological meaningful risk factors for sexual offending against children. The current study derived potential correlates of emotional congruence with children from the published literature and proposed three models of emotional congruence with children that contain relatively unique sets of correlates: the blockage, sexual deviance, and psychological immaturity models. Using Area under the Curve analysis, we assessed the relationship between emotional congruence with children and offense characteristics, victim demographics, and psychologically meaningful risk factors in a sample of incarcerated sexual offenders against children (n=221). The sexual deviance model received the most support: emotional congruence with children was significantly associated with deviant sexual interests, sexual self-regulation problems, and cognition that condones and supports child molestation. The blockage model received partial support, and the immaturity model received the least support. Based on the results, we propose a set of further predictions regarding the relationships between emotional congruence with children and other psychologically meaningful risk factors to be examined in future research. Copyright © 2013 Elsevier Ltd. All rights reserved.

Psychosocial and behavioural correlates of attitudes towards antiretroviral therapy (ART) in a sample of South African mineworkers.

Science.gov (United States)

Govender, Kaymarlin; Akintola, Olagoke; George, Gavin; Petersen, Inge; Bhagwanjee, Anil; Reardon, Candice

2011-01-01

Despite being one of the worst affected sectors in South Africa, the mining sector has proven to be one of the most active in intervention efforts in the fight against HIV and AIDS (Ellis, 2007). Owing to low uptake rates of antiretroviral therapy (ART) in mining companies in recent years (Connelly & Rosen, 2006) and the positive relationship between attitudes towards ART and ART uptake (Cooper et al., 2002; Horne, Cooper, Gellaitry, Leake, & Fisher, 2007), this study sought to describe and investigate the psychosocial and behavioural correlates of attitudes towards ART in a sample of South African mineworkers. A total of 806 mineworkers from a large South African mine participated in this quantitative study. Despite a high rate of HIV testing behaviour (83.0%) as well as favourable attitudes towards ART, analysis indicated that temporary employees and contractors were more vulnerable in terms of HIV risk, HIV testing behaviours and ART knowledge and attitudes. Employees who had more positive attitudes towards ART were more knowledgeable of ART and, importantly, had a more favourable attitude towards the mine's HIV/AIDS treatment programme. These findings are discussed in relation to the low ART uptake rates in this context and recommendations for the improvement of ART uptake amongst employees at this mining site.

Improvement of correlated sampling Monte Carlo methods for reactivity calculations

International Nuclear Information System (INIS)

Nakagawa, Masayuki; Asaoka, Takumi

1978-01-01

Two correlated Monte Carlo methods, the similar flight path and the identical flight path methods, have been improved to evaluate up to the second order change of the reactivity perturbation. Secondary fission neutrons produced by neutrons having passed through perturbed regions in both unperturbed and perturbed systems are followed in a way to have a strong correlation between secondary neutrons in both the systems. These techniques are incorporated into the general purpose Monte Carlo code MORSE, so as to be able to estimate also the statistical error of the calculated reactivity change. The control rod worths measured in the FCA V-3 assembly are analyzed with the present techniques, which are shown to predict the measured values within the standard deviations. The identical flight path method has revealed itself more useful than the similar flight path method for the analysis of the control rod worth. (auth.)

Addictive Potential of Internet Applications and Differential Correlates of Problematic Use in Internet Gamers versus Generalized Internet Users in a Representative Sample of Adolescents.

Science.gov (United States)

Rosenkranz, Tabea; Müller, Kai W; Dreier, Michael; Beutel, Manfred E; Wölfling, Klaus

2017-01-01

This paper examines the addictive potential of 8 different Internet applications, distinguishing male and female users. Moreover, differential correlates of problematic use are investigated in Internet gamers (IG) and generalized Internet users (GIU). In a representative sample of 5,667 adolescents aged 12-19 years, use of Internet applications, problematic Internet use, psychopathologic symptoms (emotional problems, hyperactivity/inattention, and psychosomatic complaints), personality (conscientiousness and extraversion), psychosocial correlates (perceived stress and self-efficacy), and coping strategies were assessed. The addictive potential of Internet applications was examined in boys and girls using regression analysis. MANOVAs were conducted to examine differential correlates of problematic Internet use between IG and GIU. Chatting and social networking most strongly predicted problematic Internet use in girls, while gaming was the strongest predictor in boys. Problematic IG exhibited multiple psychosocial problems compared to non-problematic IG. In problematic Internet users, GIU reported even higher psychosocial burden and displayed dysfunctional coping strategies more frequently than gamers. The results extend previous findings on the addictive potential of Internet applications and validate the proposed distinction between specific and generalized problematic Internet use. In addition to Internet gaming disorder, future studies should also focus on other highly addictive Internet applications, that is, chatting or social networking, regarding differential correlates of problematic use. © 2017 S. Karger AG, Basel.

A Correlational Study of Students' Theoretical and Practical

African Journals Online (AJOL)

Galadanci & Mukhtar

Science World Journal Vol 12(No 2) 2017 ... Scores in Computer Applications Courses in Bayero University Kano. A CORRELATIONAL STUDY OF STUDENTS ... Physics, Chemistry and Biology, where the course of study has a substantial ...

Estimation of rank correlation for clustered data.

Science.gov (United States)

Rosner, Bernard; Glynn, Robert J

2017-06-30

It is well known that the sample correlation coefficient (R xy ) is the maximum likelihood estimator of the Pearson correlation (ρ xy ) for independent and identically distributed (i.i.d.) bivariate normal data. However, this is not true for ophthalmologic data where X (e.g., visual acuity) and Y (e.g., visual field) are available for each eye and there is positive intraclass correlation for both X and Y in fellow eyes. In this paper, we provide a regression-based approach for obtaining the maximum likelihood estimator of ρ xy for clustered data, which can be implemented using standard mixed effects model software. This method is also extended to allow for estimation of partial correlation by controlling both X and Y for a vector U_ of other covariates. In addition, these methods can be extended to allow for estimation of rank correlation for clustered data by (i) converting ranks of both X and Y to the probit scale, (ii) estimating the Pearson correlation between probit scores for X and Y, and (iii) using the relationship between Pearson and rank correlation for bivariate normally distributed data. The validity of the methods in finite-sized samples is supported by simulation studies. Finally, two examples from ophthalmology and analgesic abuse are used to illustrate the methods. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Psychosocial correlates of police-registered youth crime. A Finnish population-based study.

Science.gov (United States)

Elonheimo, Henrik; Sourander, Andre; Niemelä, Solja; Nuutila, Ari-Matti; Helenius, Hans; Sillanmäki, Lauri; Ristkari, Terja; Parkkola, Kai

2009-01-01

This study is focused on psychosocial correlates of youth crime in a sample of 2330 Finnish boys born in 1981. Two kinds of data were combined: questionnaires completed by the boys at call-up in 1999 and crime registered in the Finnish National Police Register between 1998 and 2001. One-fifth of the boys were registered to offending during the 4-year period in late adolescence; 14% were registered for one or two offences, 4% for three to five offences, and 3% for more than five offences. Crime accumulated heavily in those with more than five offences, as they accounted for 68% of all crime. Independent correlates of crime were living in a small community, parents' low educational level and divorce, having a regular relationship, self-reported delinquency, daily smoking, and weekly drunkenness, whereas anxious-depressiveness was reversely associated with crime. Most psychosocial problems covaried linearly with offending frequency, being particularly manifested by multiple recidivists. However, recidivists had very rarely used mental health services. The results indicate that offending and various psychosocial problems accumulate in a small minority of boys not reached by mental health services.

Pion correlations and resonance effects in pbarp annihilation at rest

International Nuclear Information System (INIS)

Weber, Peter

1999-01-01

We study ππ correlations in the exclusive reactions pbarp → 2π + 2π - and pbarp → 2π + 2π - π 0 at rest with complete reconstruction of the kinematics for each event. A new analysis technique has been developed which is model independent. With this new technique, which relies on double-differential distributions, no reference sample is needed to extract the correlation signal. The correlations are studied as a function of the four-pion invariant mass

Study of the Correlation Between Contact Angle Values with the Polarity of Liquids

OpenAIRE

Syahara, Muhammad Alwi; Kurniawan, Fredy; Anggriawan, Wahyu

2015-01-01

Contact angle measurement is a technique which can be used to determine the surface properties of a substance and observe the interaction of surfaces. When polar liquid dropped on a non-polar solid, it will make an interaction that can observed from the contact angle. In simple way, the different polarity of the solid and the liquid sample will affect to the contact angle obtained. In this work the value of contact angle will be correlated to the polarity of the sample. The results showed tha...

Correlated binomial models and correlation structures

International Nuclear Information System (INIS)

Hisakado, Masato; Kitsukawa, Kenji; Mori, Shintaro

2006-01-01

We discuss a general method to construct correlated binomial distributions by imposing several consistent relations on the joint probability function. We obtain self-consistency relations for the conditional correlations and conditional probabilities. The beta-binomial distribution is derived by a strong symmetric assumption on the conditional correlations. Our derivation clarifies the 'correlation' structure of the beta-binomial distribution. It is also possible to study the correlation structures of other probability distributions of exchangeable (homogeneous) correlated Bernoulli random variables. We study some distribution functions and discuss their behaviours in terms of their correlation structures

Correlation of psychomotor skills and didactic performance among dental students in Saudi Arabia.

Science.gov (United States)

Afify, Ahmed R; Zawawi, Khalid H; Othman, Hisham I; Al-Dharrab, Ayman A

2013-01-01

The objective of this study is to investigate the correlation between the psychomotor skills and the academic performance of dental students. Didactic and preclinical scores were collected for students who graduated from the Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia, in 2011. Three courses (Dental Anatomy, Removable Prosthodontic Denture, and Orthodontics) were selected. Correlations comparing didactic and practical scores were done for the total samples, then for the males and females separately. There was no significant correlation between the practical and didactic scores for the three courses for the total sample. There was a significant correlation between all three subjects in the didactic scores. For females, the results showed that there was only a significant correlation between the practical and didactic scores for Dental Anatomy. For males, no correlation was observed between the practical and didactic scores for all subjects. In the present sample, didactic performance did not correlate well with the students' psychomotor performance.

Factors Effecting Adsorption of 137 Cs in Marine Sediment Samples in Marine Sediment Samples from the Upper Gulf of Thailand

International Nuclear Information System (INIS)

Saengkul, C.; Sawangwong, P.; Pakkong, P.

2014-01-01

Contamination of 137 Cs in sediment is a far more serious problem than in water because sediment is a main transport factor of 137 Cs to the aquatic environmental. Most of 137 Cs in water could be accumulated in sediment which has direct effect to benthos. This study focused on factors effecting the adsorption of 137Cs in marine sediment samples collected from four different estuary sites to assess the transfer direction of 137 Cs from water to sediment that the study method by treat 137 Cs into seawater and mixed with different sediment samples for 4 days. The result indicated that properties of marine sediment (cation exchange capacity (CEC), organic matter, clay content, texture, type of clay mineral and size of soil particle) had effects on 137 Cs adsorption. CEC and clay content correlated positively with the accumulation of 137 Cs in the marine sediment samples. On the other hand, organic matter in sediment correlated negatively with the accumulation of 137 Cs in samples. The study of environmental effects (pH and potassium) found that the 137 Cs adsorption decreased when concentration of potassium increased. The pH effect is still unclear in this study because the differentiation of pH levels (6, 7, 8.3) did not have effects on 137 Cs adsorption in the samples.

Prevalence study of compulsive buying in a sample with low individual monthly income.

Science.gov (United States)

Leite, Priscilla Lourenço; Silva, Adriana Cardoso

2015-01-01

Compulsive buying can be characterized as an almost irresistible impulse to acquire various items. This is a current issue and the prevalence rate in the global population is around 5 to 8%. Some surveys indicate that the problem is growing in young and low-income populations. To evaluate the prevalence of compulsive buying among people with low personal monthly incomes and analyze relationships with socio-demographic data. The Compulsive Buying Scale was administered to screen for compulsive buying and the Hospital Anxiety and Depression Scale was used to assess anxiety and depression in a sample of 56 participants. Pearson coefficients were used to test for correlations. The results indicated that 44.6% presented an average family income equal to or greater than 2.76 minimum wages. It is possible that compulsive buying is not linked to the purchasing power since it was found in a low-income population. Despite the small sample, the results of this study are important for understanding the problem in question.

Correlates of weight status among Norwegian 11-year-olds: The HEIA study

Directory of Open Access Journals (Sweden)

Grydeland May

2012-12-01

Full Text Available Abstract Background The underlying mechanisms of overweight and obesity in adolescents are still not fully understood. The aim of this study was to investigate modifiable and non-modifiable correlates of weight status among 1103 Norwegian 11-year-old adolescents in the HEalth in Adolescents (HEIA study, including demographic factors such as gender and parental education, and behavioral factors such as intake of sugar-sweetened beverages, snacks and breakfast consumption, watching TV and playing computer games, physical activity and sedentary time. Methods Weight and height were measured objectively, body mass index (BMI was calculated and International Obesity Task Force cut-offs were used to define weight status. Physical activity and sedentary time were measured by accelerometers. Other behavioral correlates and pubertal status were self-reported by questionnaires. Parental education was reported by the parents on the consent form for their child. Associations were investigated using logistic regressions. Results There were gender differences in behavioral correlates of weight status but not for weight status itself. Adolescents with parents in the highest education category had a 46% reduced odds of being overweight compared to adolescents with parents in the lowest education category. Adolescents with parents with medium education had 42% lower odds of being overweight than adolescents with parents with the lowest education category. Level of parental education, breakfast consumption and moderate to vigorous physical activity were positively associated with being normal weight, and time watching TV was positively associated with being overweight for the total sample. Gender differences were detected; boys had a doubled risk of being overweight for every additional hour of watching TV per week, while for girls there was no association. Conclusions The present study showed a social gradient in weight status in 11-year-olds. Both breakfast

Systematic versus random sampling in stereological studies.

Science.gov (United States)

West, Mark J

2012-12-01

The sampling that takes place at all levels of an experimental design must be random if the estimate is to be unbiased in a statistical sense. There are two fundamental ways by which one can make a random sample of the sections and positions to be probed on the sections. Using a card-sampling analogy, one can pick any card at all out of a deck of cards. This is referred to as independent random sampling because the sampling of any one card is made without reference to the position of the other cards. The other approach to obtaining a random sample would be to pick a card within a set number of cards and others at equal intervals within the deck. Systematic sampling along one axis of many biological structures is more efficient than random sampling, because most biological structures are not randomly organized. This article discusses the merits of systematic versus random sampling in stereological studies.

How Many Conformations of Enzymes Should Be Sampled for DFT/MM Calculations? A Case Study of Fluoroacetate Dehalogenase

Directory of Open Access Journals (Sweden)

Yanwei Li

2016-08-01

Full Text Available The quantum mechanics/molecular mechanics (QM/MM method (e.g., density functional theory (DFT/MM is important in elucidating enzymatic mechanisms. It is indispensable to study “multiple” conformations of enzymes to get unbiased energetic and structural results. One challenging problem, however, is to determine the minimum number of conformations for DFT/MM calculations. Here, we propose two convergence criteria, namely the Boltzmann-weighted average barrier and the disproportionate effect, to tentatively address this issue. The criteria were tested by defluorination reaction catalyzed by fluoroacetate dehalogenase. The results suggest that at least 20 conformations of enzymatic residues are required for convergence using DFT/MM calculations. We also tested the correlation of energy barriers between small QM regions and big QM regions. A roughly positive correlation was found. This kind of correlation has not been reported in the literature. The correlation inspires us to propose a protocol for more efficient sampling. This saves 50% of the computational cost in our current case.

Correlation between the synthetic origin of methamphetamine samples and their {sup 15}N and {sup 13}C stable isotope ratios

Energy Technology Data Exchange (ETDEWEB)

Billault, Isabelle [Laboratoire d' Analyse Isotopique et Electrochimique de Metabolismes, CNRS UMR6006, University of Nantes, BP 92208, 44322 Nantes (France)]. E-mail: Isabelle.Billault@univ-nantes.fr; Courant, Frederique [Laboratoire d' Analyse Isotopique et Electrochimique de Metabolismes, CNRS UMR6006, University of Nantes, BP 92208, 44322 Nantes (France); Pasquereau, Leo [Laboratoire d' Analyse Isotopique et Electrochimique de Metabolismes, CNRS UMR6006, University of Nantes, BP 92208, 44322 Nantes (France); Derrien, Solene [Laboratoire d' Analyse Isotopique et Electrochimique de Metabolismes, CNRS UMR6006, University of Nantes, BP 92208, 44322 Nantes (France); Robins, Richard J. [Laboratoire d' Analyse Isotopique et Electrochimique de Metabolismes, CNRS UMR6006, University of Nantes, BP 92208, 44322 Nantes (France); Naulet, Norbert [Laboratoire d' Analyse Isotopique et Electrochimique de Metabolismes, CNRS UMR6006, University of Nantes, BP 92208, 44322 Nantes (France)

2007-06-12

The active ingredient of ecstasy, N-methyl-3,4-methyldioxyphenylisopropylamine (MDMA) can be manufactured by a number of easy routes from simple precursors. We have synthesised 45 samples of MDMA following the five most common routes using N-precursors from 12 different origins and three different precursors for the aromatic moiety. The {sup 13}C and {sup 15}N contents of both the precursors and the MDMA samples derived therefrom were measured by isotope ratio mass spectrometry coupled to an elemental analyser (EA-IRMS). We show that within-pathway correlation between the {sup 15}N content of the precursor and that of the derived MDMA can be strong but that no general pattern of correlation can be defined. Rather, it is evident that the {delta} {sup 15}N values of MDMA are strongly influenced by a combination of the {delta} {sup 15}N values of the source of nitrogen used, the route by which the MDMA is synthesised, and the experimental conditions employed. Multivariate analysis (PCA) based on the {delta} {sup 15}N values of the synthetic MDMA and of the {delta} {sup 15}N and {delta} {sup 13}C values of the N-precursors leads to good discrimination between the majority of the reaction conditions tested.

Correlates of Total Sedentary Time and Screen Time in 9-11 Year-Old Children around the World: The International Study of Childhood Obesity, Lifestyle and the Environment.

Directory of Open Access Journals (Sweden)

Allana G LeBlanc

Full Text Available Previously, studies examining correlates of sedentary behavior have been limited by small sample size, restricted geographic area, and little socio-cultural variability. Further, few studies have examined correlates of total sedentary time (SED and screen time (ST in the same population. This study aimed to investigate correlates of SED and ST in children around the world.The sample included 5,844 children (45.6% boys, mean age = 10.4 years from study sites in Australia, Brazil, Canada, China, Colombia, Finland, India, Kenya, Portugal, South Africa, the United Kingdom, and the United States. Child- and parent-reported behavioral, household, and neighborhood characteristics and directly measured anthropometric and accelerometer data were obtained. Twenty-one potential correlates of SED and ST were examined using multilevel models, adjusting for sex, age, and highest parental education, with school and study site as random effects. Variables that were moderately associated with SED and/or ST in univariate analyses (p<0.10 were included in the final models. Variables that remained significant in the final models (p<0.05 were considered correlates of SED and/or ST.Children averaged 8.6 hours of daily SED, and 54.2% of children failed to meet ST guidelines. In all study sites, boys reported higher ST, were less likely to meet ST guidelines, and had higher BMI z-scores than girls. In 9 of 12 sites, girls engaged in significantly more SED than boys. Common correlates of higher SED and ST included poor weight status, not meeting physical activity guidelines, and having a TV or a computer in the bedroom.In this global sample many common correlates of SED and ST were identified, some of which are easily modifiable (e.g., removing TV from the bedroom, and others that may require more intense behavioral interventions (e.g., increasing physical activity. Future work should incorporate these findings into the development of culturally meaningful public health

Population models and simulation methods: The case of the Spearman rank correlation.

Science.gov (United States)

Astivia, Oscar L Olvera; Zumbo, Bruno D

2017-11-01

The purpose of this paper is to highlight the importance of a population model in guiding the design and interpretation of simulation studies used to investigate the Spearman rank correlation. The Spearman rank correlation has been known for over a hundred years to applied researchers and methodologists alike and is one of the most widely used non-parametric statistics. Still, certain misconceptions can be found, either explicitly or implicitly, in the published literature because a population definition for this statistic is rarely discussed within the social and behavioural sciences. By relying on copula distribution theory, a population model is presented for the Spearman rank correlation, and its properties are explored both theoretically and in a simulation study. Through the use of the Iman-Conover algorithm (which allows the user to specify the rank correlation as a population parameter), simulation studies from previously published articles are explored, and it is found that many of the conclusions purported in them regarding the nature of the Spearman correlation would change if the data-generation mechanism better matched the simulation design. More specifically, issues such as small sample bias and lack of power of the t-test and r-to-z Fisher transformation disappear when the rank correlation is calculated from data sampled where the rank correlation is the population parameter. A proof for the consistency of the sample estimate of the rank correlation is shown as well as the flexibility of the copula model to encompass results previously published in the mathematical literature. © 2017 The British Psychological Society.

Sample size calculations for case-control studies

Science.gov (United States)

This R package can be used to calculate the required samples size for unconditional multivariate analyses of unmatched case-control studies. The sample sizes are for a scalar exposure effect, such as binary, ordinal or continuous exposures. The sample sizes can also be computed for scalar interaction effects. The analyses account for the effects of potential confounder variables that are also included in the multivariate logistic model.

Personality correlates of type 1 diabetes in a national representative sample

OpenAIRE

Čukić, Iva; Weiss, Alexander

2016-01-01

We examined cross-sectional relationships between personality traits and type 1 diabetes. The sample (N=8490) was taken from the 1982-84 wave of the National Health and Nutrition Examination Survey Epidemiological Follow-up Study. We fit three logistic regression models to test whether neuroticism, extraversion, openness, or the Type A behavior pattern were associated with type 1 diabetes. Model 1 included sex, age, race/ethnicity and all four personality traits. Model 2 added depressive symp...

Mars Sample Return Architecture Assessment Study

Science.gov (United States)

Centuori, S.; Hermosín, P.; Martín, J.; De Zaiacomo, G.; Colin, S.; Godfrey, A.; Myles, J.; Johnson, H.; Sachdev, T.; Ahmed, R.

2018-04-01

Current paper presents the results of ESA funded activity "Mars Sample Return Architecture Assessment Study" carried-out by DEIMOS Space, Lockheed Martin UK Ampthill, and MDA Corporation, where more than 500 mission design options have been studied.

Positron annihilation and perturbed angular correlation studies of radiation damage

International Nuclear Information System (INIS)

Zhu Jiazheng; Li Anli; Xu Yongjun; Wang Zhiqiang; Zhou Dongmei; Zheng Yongnan; Zhu Shengyun; Iwata, T.

2002-01-01

The positron annihilation and perturbed angular correlation techniques have been employed to study radiation damage in Si and Nb. The results obtained by the positron annihilation are consistent with those given by the perturbed angular correlation

Comparison of mucosal lining fluid sampling methods and influenza-specific IgA detection assays for use in human studies of influenza immunity.

Science.gov (United States)

de Silva, Thushan I; Gould, Victoria; Mohammed, Nuredin I; Cope, Alethea; Meijer, Adam; Zutt, Ilse; Reimerink, Johan; Kampmann, Beate; Hoschler, Katja; Zambon, Maria; Tregoning, John S

2017-10-01

We need greater understanding of the mechanisms underlying protection against influenza virus to develop more effective vaccines. To do this, we need better, more reproducible methods of sampling the nasal mucosa. The aim of the current study was to compare levels of influenza virus A subtype-specific IgA collected using three different methods of nasal sampling. Samples were collected from healthy adult volunteers before and after LAIV immunization by nasal wash, flocked swabs and Synthetic Absorptive Matrix (SAM) strips. Influenza A virus subtype-specific IgA levels were measured by haemagglutinin binding ELISA or haemagglutinin binding microarray and the functional response was assessed by microneutralization. Nasosorption using SAM strips lead to the recovery of a more concentrated sample of material, with a significantly higher level of total and influenza H1-specific IgA. However, an equivalent percentage of specific IgA was observed with all sampling methods when normalized to the total IgA. Responses measured using a recently developed antibody microarray platform, which allows evaluation of binding to multiple influenza strains simultaneously with small sample volumes, were compared to ELISA. There was a good correlation between ELISA and microarray values. Material recovered from SAM strips was weakly neutralizing when used in an in vitro assay, with a modest correlation between the level of IgA measured by ELISA and neutralization, but a greater correlation between microarray-measured IgA and neutralizing activity. In conclusion we have tested three different methods of nasal sampling and show that flocked swabs and novel SAM strips are appropriate alternatives to traditional nasal washes for assessment of mucosal influenza humoral immunity. Copyright © 2017 Elsevier B.V. All rights reserved.

Projection correlation between two random vectors.

Science.gov (United States)

Zhu, Liping; Xu, Kai; Li, Runze; Zhong, Wei

2017-12-01

We propose the use of projection correlation to characterize dependence between two random vectors. Projection correlation has several appealing properties. It equals zero if and only if the two random vectors are independent, it is not sensitive to the dimensions of the two random vectors, it is invariant with respect to the group of orthogonal transformations, and its estimation is free of tuning parameters and does not require moment conditions on the random vectors. We show that the sample estimate of the projection correction is [Formula: see text]-consistent if the two random vectors are independent and root-[Formula: see text]-consistent otherwise. Monte Carlo simulation studies indicate that the projection correlation has higher power than the distance correlation and the ranks of distances in tests of independence, especially when the dimensions are relatively large or the moment conditions required by the distance correlation are violated.

Mutagenicity of drinking water sampled from the Yangtze River and Hanshui River (Wuhan section) and correlations with water quality parameters.

Science.gov (United States)

Lv, Xuemin; Lu, Yi; Yang, Xiaoming; Dong, Xiaorong; Ma, Kunpeng; Xiao, Sanhua; Wang, Yazhou; Tang, Fei

2015-03-31

A total of 54 water samples were collected during three different hydrologic periods (level period, wet period, and dry period) from Plant A and Plant B (a source for Yangtze River and Hanshui River water, respectively), and several water parameters, such as chemical oxygen demand (COD), turbidity, and total organic carbon (TOC), were simultaneously analyzed. The mutagenicity of the water samples was evaluated using the Ames test with Salmonella typhimurium strains TA98 and TA100. According to the results, the organic compounds in the water were largely frame-shift mutagens, as positive results were found for most of the tests using TA98. All of the finished water samples exhibited stronger mutagenicity than the relative raw and distribution water samples, with water samples collected from Plant B presenting stronger mutagenic strength than those from Plant A. The finished water samples from Plant A displayed a seasonal-dependent variation. Water parameters including COD (r = 0.599, P = 0.009), TOC (r = 0.681, P = 0.02), UV254 (r = 0.711, P = 0.001), and total nitrogen (r = 0.570, P = 0.014) exhibited good correlations with mutagenicity (TA98), at 2.0 L/plate, which bolsters the argument of the importance of using mutagenicity as a new parameter to assess the quality of drinking water.

Correlation between laser-induced breakdown spectroscopy signal and moisture content

International Nuclear Information System (INIS)

Liu, Yuan; Gigant, Lionel; Baudelet, Matthieu; Richardson, Martin

2012-01-01

The possibility of using Laser-Induced Breakdown Spectroscopy (LIBS) for measuring the moisture content of fresh food samples is studied. The normalized line emission of oxygen is highly correlated with the moisture content of the sample, cheese in our case, and can be used as a moisture marker in situations where oxygen interference from the matrix is not a critical issue. The linear correlation between the oxygen signal and the moisture content in the sample shows great potential for using LIBS as an alternative spectroscopic method for moisture monitoring. - Highlights: ► Quantitative moisture measurement by LIBS. ► Use of matrix effects and normalization for physical information on the sample. ► Use of signal from oxygen and CN radical in air background for moisture measurement.

Correlated optical and isotopic nanoscopy

Science.gov (United States)

Saka, Sinem K.; Vogts, Angela; Kröhnert, Katharina; Hillion, François; Rizzoli, Silvio O.; Wessels, Johannes T.

2014-04-01

The isotopic composition of different materials can be imaged by secondary ion mass spectrometry. In biology, this method is mainly used to study cellular metabolism and turnover, by pulsing the cells with marker molecules such as amino acids labelled with stable isotopes (15N, 13C). The incorporation of the markers is then imaged with a lateral resolution that can surpass 100 nm. However, secondary ion mass spectrometry cannot identify specific subcellular structures like organelles, and needs to be correlated with a second technique, such as fluorescence imaging. Here, we present a method based on stimulated emission depletion microscopy that provides correlated optical and isotopic nanoscopy (COIN) images. We use this approach to study the protein turnover in different organelles from cultured hippocampal neurons. Correlated optical and isotopic nanoscopy can be applied to a variety of biological samples, and should therefore enable the investigation of the isotopic composition of many organelles and subcellular structures.

Kolmogorov-Smirnov test for spatially correlated data

Science.gov (United States)

Olea, R.A.; Pawlowsky-Glahn, V.

2009-01-01

The Kolmogorov-Smirnov test is a convenient method for investigating whether two underlying univariate probability distributions can be regarded as undistinguishable from each other or whether an underlying probability distribution differs from a hypothesized distribution. Application of the test requires that the sample be unbiased and the outcomes be independent and identically distributed, conditions that are violated in several degrees by spatially continuous attributes, such as topographical elevation. A generalized form of the bootstrap method is used here for the purpose of modeling the distribution of the statistic D of the Kolmogorov-Smirnov test. The innovation is in the resampling, which in the traditional formulation of bootstrap is done by drawing from the empirical sample with replacement presuming independence. The generalization consists of preparing resamplings with the same spatial correlation as the empirical sample. This is accomplished by reading the value of unconditional stochastic realizations at the sampling locations, realizations that are generated by simulated annealing. The new approach was tested by two empirical samples taken from an exhaustive sample closely following a lognormal distribution. One sample was a regular, unbiased sample while the other one was a clustered, preferential sample that had to be preprocessed. Our results show that the p-value for the spatially correlated case is always larger that the p-value of the statistic in the absence of spatial correlation, which is in agreement with the fact that the information content of an uncorrelated sample is larger than the one for a spatially correlated sample of the same size. ?? Springer-Verlag 2008.

Parcellating an individual subject's cortical and subcortical brain structures using snowball sampling of resting-state correlations.

Science.gov (United States)

Wig, Gagan S; Laumann, Timothy O; Cohen, Alexander L; Power, Jonathan D; Nelson, Steven M; Glasser, Matthew F; Miezin, Francis M; Snyder, Abraham Z; Schlaggar, Bradley L; Petersen, Steven E

2014-08-01

We describe methods for parcellating an individual subject's cortical and subcortical brain structures using resting-state functional correlations (RSFCs). Inspired by approaches from social network analysis, we first describe the application of snowball sampling on RSFC data (RSFC-Snowballing) to identify the centers of cortical areas, subdivisions of subcortical nuclei, and the cerebellum. RSFC-Snowballing parcellation is then compared with parcellation derived from identifying locations where RSFC maps exhibit abrupt transitions (RSFC-Boundary Mapping). RSFC-Snowballing and RSFC-Boundary Mapping largely complement one another, but also provide unique parcellation information; together, the methods identify independent entities with distinct functional correlations across many cortical and subcortical locations in the brain. RSFC parcellation is relatively reliable within a subject scanned across multiple days, and while the locations of many area centers and boundaries appear to exhibit considerable overlap across subjects, there is also cross-subject variability-reinforcing the motivation to parcellate brains at the level of individuals. Finally, examination of a large meta-analysis of task-evoked functional magnetic resonance imaging data reveals that area centers defined by task-evoked activity exhibit correspondence with area centers defined by RSFC-Snowballing. This observation provides important evidence for the ability of RSFC to parcellate broad expanses of an individual's brain into functionally meaningful units. © The Author 2013. Published by Oxford University Press.

Burden and correlates of non-communicable-diseases among rural residents: a cross-sectional study in Hebei, China.

Science.gov (United States)

Yang, Junjun; Yu, Wenya; Zhou, Qiang; Mahapatra, Tanmay; Li, Yiqiu; Zhang, Xiaoyan; Chen, Lei; Mahapatra, Sanchita; Yan, Yuying; Tang, Weiming

2015-06-20

Burden of non-communicable diseases (NCDs) is increasing rapidly in most of the developing countries including China, even in rural areas. Dearth of representative data called for an investigation to estimate the burden and identify the correlates of NCDs in rural China. A cross-sectional study was conducted involving a representative sample of 6003 consenting randomly selected rural residents aged 15 years or more, from 36 villages of Shijiazhuang in Hebei province of China between July 2010 and June 2011. Information on demographics and behavior were collected, body mass index (BMI) and blood pressure were measured and blood samples were tested to diagnose diabetes and hyperlipidemia. Majority participants were aged problems (12.1%) and gastrointestinal NCDs (7.8%) were identified among the participants, while proportion of subjects with one, two and three or more NCDs were 43%, 14.4% and 5.5% respectively. Higher odds of having more NCDs were associated with higher BMI (Kg/M(2)), family history of NCDs, daily and past history of smoking and drinking, passive smoking, lack of exercise, skipping breakfast and psychological disturbances. Despite limitations associated with cross-sectional design and self-reporting, observation in this large sample of rural residents could develop important insights regarding high burden of NCDs in this population. Based on the identified correlates, targeted intervention strategies seem to be required urgently to control NCDs in rural China.

Sample size calculation in metabolic phenotyping studies.

Science.gov (United States)

Billoir, Elise; Navratil, Vincent; Blaise, Benjamin J

2015-09-01

The number of samples needed to identify significant effects is a key question in biomedical studies, with consequences on experimental designs, costs and potential discoveries. In metabolic phenotyping studies, sample size determination remains a complex step. This is due particularly to the multiple hypothesis-testing framework and the top-down hypothesis-free approach, with no a priori known metabolic target. Until now, there was no standard procedure available to address this purpose. In this review, we discuss sample size estimation procedures for metabolic phenotyping studies. We release an automated implementation of the Data-driven Sample size Determination (DSD) algorithm for MATLAB and GNU Octave. Original research concerning DSD was published elsewhere. DSD allows the determination of an optimized sample size in metabolic phenotyping studies. The procedure uses analytical data only from a small pilot cohort to generate an expanded data set. The statistical recoupling of variables procedure is used to identify metabolic variables, and their intensity distributions are estimated by Kernel smoothing or log-normal density fitting. Statistically significant metabolic variations are evaluated using the Benjamini-Yekutieli correction and processed for data sets of various sizes. Optimal sample size determination is achieved in a context of biomarker discovery (at least one statistically significant variation) or metabolic exploration (a maximum of statistically significant variations). DSD toolbox is encoded in MATLAB R2008A (Mathworks, Natick, MA) for Kernel and log-normal estimates, and in GNU Octave for log-normal estimates (Kernel density estimates are not robust enough in GNU octave). It is available at http://www.prabi.fr/redmine/projects/dsd/repository, with a tutorial at http://www.prabi.fr/redmine/projects/dsd/wiki. © The Author 2015. Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Gibbs sampling on large lattice with GMRF

Science.gov (United States)

Marcotte, Denis; Allard, Denis

2018-02-01

Gibbs sampling is routinely used to sample truncated Gaussian distributions. These distributions naturally occur when associating latent Gaussian fields to category fields obtained by discrete simulation methods like multipoint, sequential indicator simulation and object-based simulation. The latent Gaussians are often used in data assimilation and history matching algorithms. When the Gibbs sampling is applied on a large lattice, the computing cost can become prohibitive. The usual practice of using local neighborhoods is unsatisfying as it can diverge and it does not reproduce exactly the desired covariance. A better approach is to use Gaussian Markov Random Fields (GMRF) which enables to compute the conditional distributions at any point without having to compute and invert the full covariance matrix. As the GMRF is locally defined, it allows simultaneous updating of all points that do not share neighbors (coding sets). We propose a new simultaneous Gibbs updating strategy on coding sets that can be efficiently computed by convolution and applied with an acceptance/rejection method in the truncated case. We study empirically the speed of convergence, the effect of choice of boundary conditions, of the correlation range and of GMRF smoothness. We show that the convergence is slower in the Gaussian case on the torus than for the finite case studied in the literature. However, in the truncated Gaussian case, we show that short scale correlation is quickly restored and the conditioning categories at each lattice point imprint the long scale correlation. Hence our approach enables to realistically apply Gibbs sampling on large 2D or 3D lattice with the desired GMRF covariance.

Clinical and biochemical correlates of successful semen collection for cryopreservation from 12-18-year-old patients: a single-center study of 86 adolescents

DEFF Research Database (Denmark)

Hagenäs, Isabella; Jørgensen, Niels; Rechnitzer, Catherine

2010-01-01

Cryopreservation of semen should be offered to adults before gonadotoxic treatment. However, the experience with semen collection in adolescents is still limited. The objective of this study was to evaluate potential correlates of successful semen sampling in adolescents....

Correlation of psychomotor skills and didactic performance among dental students in Saudi Arabia

Directory of Open Access Journals (Sweden)

Afify AR

2013-10-01

Full Text Available Ahmed R Afify,1 Khalid H Zawawi,1 Hisham I Othman,2 Ayman A Al-Dharrab31Department of Preventive Dental Sciences, 2Department of Basic Oral and Clinical Sciences, 3Department of Oral and Maxillofacial Rehabilitation, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi ArabiaObjectives: The objective of this study is to investigate the correlation between the psychomotor skills and the academic performance of dental students.Methods: Didactic and preclinical scores were collected for students who graduated from the Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia, in 2011. Three courses (Dental Anatomy, Removable Prosthodontic Denture, and Orthodontics were selected. Correlations comparing didactic and practical scores were done for the total samples, then for the males and females separately.Results: There was no significant correlation between the practical and didactic scores for the three courses for the total sample. There was a significant correlation between all three subjects in the didactic scores. For females, the results showed that there was only a significant correlation between the practical and didactic scores for Dental Anatomy. For males, no correlation was observed between the practical and didactic scores for all subjects.Conclusion: In the present sample, didactic performance did not correlate well with the students' psychomotor performance.Keywords: psychomotor performance, didactic performance, dental students, correlation study, dental education, practical performance

Correlation of Salivary Glucose Level with Blood Glucose Level in Diabetes Mellitus

Directory of Open Access Journals (Sweden)

Arati S. Panchbhai

2012-07-01

Full Text Available Objectives: There is alarming rise in number of people with diabetes mellitus over these years. If glucose in saliva is linked to glucose in blood it can be used to detect diabetes mellitus at an early stage. The present study is undertaken with the aim to assess the correlation of salivary glucose level with blood glucose level in people with diabetes mellitus. Material and Methods: For investigations, 2 sets of samples of people with diabetes and the age and sex matched non-diabetic subjects were recruited. The salivary glucose was analyzed in unstimulated whole saliva samples using glucose oxidase method. Pearson’s correlation coefficient test was applied to assess the correlation between salivary glucose level and blood glucose level. Results: The significant (P < 0.05 positive correlation of salivary glucose level and fasting blood glucose level was observed in people with uncontrolled diabetes in both the sets of samples.Conclusions: Although study suggests some potential for saliva as a marker in monitoring of diabetes mellitus, there are many aspects that need clarification before we reach to a conclusion.

Neuromuscular dose-response studies: determining sample size.

Science.gov (United States)

Kopman, A F; Lien, C A; Naguib, M

2011-02-01

Investigators planning dose-response studies of neuromuscular blockers have rarely used a priori power analysis to determine the minimal sample size their protocols require. Institutional Review Boards and peer-reviewed journals now generally ask for this information. This study outlines a proposed method for meeting these requirements. The slopes of the dose-response relationships of eight neuromuscular blocking agents were determined using regression analysis. These values were substituted for γ in the Hill equation. When this is done, the coefficient of variation (COV) around the mean value of the ED₅₀ for each drug is easily calculated. Using these values, we performed an a priori one-sample two-tailed t-test of the means to determine the required sample size when the allowable error in the ED₅₀ was varied from ±10-20%. The COV averaged 22% (range 15-27%). We used a COV value of 25% in determining the sample size. If the allowable error in finding the mean ED₅₀ is ±15%, a sample size of 24 is needed to achieve a power of 80%. Increasing 'accuracy' beyond this point requires increasing greater sample sizes (e.g. an 'n' of 37 for a ±12% error). On the basis of the results of this retrospective analysis, a total sample size of not less than 24 subjects should be adequate for determining a neuromuscular blocking drug's clinical potency with a reasonable degree of assurance.

Study of phosphors determination in biological samples

International Nuclear Information System (INIS)

Oliveira, Rosangela Magda de.

1994-01-01

In this paper, phosphors determination by neutron activation analysis in milk and bone samples was studied employing both instrumental and radiochemical separation methods. The analysis with radiochemistry separation consisted of the simultaneous irradiation of the samples and standards during 30 minutes, dissolution of the samples, hold back carrier, addition precipitation of phosphorus with ammonium phosphomolibdate (A.M.P.) and phosphorus-32 by counting by using Geiger-Mueller detector. The instrumental analysis consisted of the simultaneous irradiation of the samples and standards during 30 minutes, transfer of the samples into a counting planchet and measurement of the beta radiation emitted by phosphorus-32, after a suitable decay period. After the phosphorus analysis methods were established they were applied to both commercial milk and animal bone samples, and data obtained in the instrumental and radiochemical separation methods for each sample, were compared between themselves. In this work, it became possible to obtain analysis methods for phosphorus that can be applied independently of the sample quantity available, and the phosphorus content in the samples or interference that can be present in them. (author). 51 refs., 7 figs., 4 tabs

Epidemiological investigation of the UGT2B17 polymorphism in doping control urine samples and its correlation to T/E ratios.

Science.gov (United States)

Anielski, Patricia; Simmchen, Juliane; Wassill, Lars; Ganghofner, Dirk; Thieme, Detlef

2011-10-01

The deletion polymorphism of the enzyme UGT2B17 is known to correlate with the level of the testosterone to epitestosterone (T/E) ratio in urine specimen. Due to the importance of the T/E ratio to detect testosterone abuse in doping analysis, a PCR-ELISA system (Genotype® UGT test, AmplexDiagnostics) was established to identify the UGT2B17 phenotype in urine samples. Epidemiological investigations in a set of 674 routine doping controls (in- and out-of-competition) resulted in 22.8% homozygote gene-deleted and 74.5% UGT2B17-positive athletes. The validated test system has shown to be robust and sensitive: in only 18 cases (2.7%) isolation of cell material from urine failed. Following hydrolysis of glucuronidated conjugates, steroids were analyzed as bis-TMS derivatives by gas chromatography-mass spectrometry (GC-MS), for example, testosterone (T) and epitestosterone (E). Additionally, isotope ration mass spectrometry (IRMS) analysis and luteinizing hormone (LH) measurement were applied. Mean T/E ratios significantly correlated with the UGT2B17 phenotype (del: T/E 0.9; pos: 1.7), however the values did not differ as distinctive as reported in previous studies. Additionally, the T/E ratios in the gene-deleted group did not show a normal curve of distribution (median of T/E 0.5). Obviously, beside the UGT2B17 deletion further influences have to be taken into account, for example, polymorphisms or induction of other metabolizing enzymes. Our results indicate that the UGT2B17 polymorphism might be insufficient when utilized solely as a crucial parameter for individual interpretation of T/E in urine. Nevertheless, the detection of the UGT2B17-gene deletion in urine samples would provide additional information important for gathering evidence in analysis of steroids in doping control. Copyright © 2011 John Wiley & Sons, Ltd.

Structural Correlates of Skilled Performance on a Motor Sequence Task

Directory of Open Access Journals (Sweden)

Christopher J Steele

2012-10-01

Full Text Available The brain regions functionally engaged in motor sequence performance are well established, but the structural characteristics of these regions and the fibre pathways involved have been less well studied. In addition, relatively few studies have combined multiple magnetic resonance imaging (MRI and behavioural performance measures in the same sample. Therefore, the current study used diffusion tensor imaging, probabilistic tractography, and voxel-based morphometry to determine the structural correlates of skilled motor performance. Further, we compared these findings with fMRI results in the same sample. We correlated final performance and rate of improvement measures on a temporal motor sequence task with skeletonised fractional anisotropy (FA and whole brain grey matter (GM volume. Final synchronisation performance was negatively correlated with FA in white matter underlying bilateral sensorimotor cortex – an effect that was mediated by a positive correlation with radial diffusivity. Multi-fibre tractography indicated that this region contained crossing fibres from the corticospinal tract and superior longitudinal fasciculus (SLF. The identified SLF pathway linked parietal and auditory cortical regions that have been shown to be functionally engaged in this task. Thus, we hypothesise that enhanced synchronisation performance on this task may be related to greater fibre integrity of the SLF. Rate of improvement on synchronisation was positively correlated with GM volume in cerebellar lobules HVI and V – regions that showed training-related decreases in activity in the same sample. Taken together, our results link individual differences in brain structure and function to motor sequence performance on the same task. Further, our study illustrates the utility of using multiple MR measures and analysis techniques to specify the interpretation of structural findings.

Principal components in the discrimination of outliers: A study in simulation sample data corrected by Pearson's and Yates´s chi-square distance

Directory of Open Access Journals (Sweden)

Manoel Vitor de Souza Veloso

2016-04-01

Full Text Available Current study employs Monte Carlo simulation in the building of a significance test to indicate the principal components that best discriminate against outliers. Different sample sizes were generated by multivariate normal distribution with different numbers of variables and correlation structures. Corrections by chi-square distance of Pearson´s and Yates's were provided for each sample size. Pearson´s correlation test showed the best performance. By increasing the number of variables, significance probabilities in favor of hypothesis H0 were reduced. So that the proposed method could be illustrated, a multivariate time series was applied with regard to sales volume rates in the state of Minas Gerais, obtained in different market segments.

Two-dimensional correlation spectroscopy in polymer study

Science.gov (United States)

Park, Yeonju; Noda, Isao; Jung, Young Mee

2015-01-01

This review outlines the recent works of two-dimensional correlation spectroscopy (2DCOS) in polymer study. 2DCOS is a powerful technique applicable to the in-depth analysis of various spectral data of polymers obtained under some type of perturbation. The powerful utility of 2DCOS combined with various analytical techniques in polymer studies and noteworthy developments of 2DCOS used in this field are also highlighted. PMID:25815286

Mindfulness, perceived stress, and subjective well-being: a correlational study in primary care health professionals.

Science.gov (United States)

Atanes, Ana C M; Andreoni, Solange; Hirayama, Marcio S; Montero-Marin, Jesús; Barros, Viviam V; Ronzani, Telmo M; Kozasa, Eliza H; Soler, Joaquim; Cebolla, Ausiàs; Garcia-Campayo, Javier; Demarzo, Marcelo M P

2015-09-02

Primary health care professionals (PHPs) usually report high levels of distress and burnout symptoms related to job strain. Mindfulness, defined as non-judgmental-present-moment awareness, seems to be a moderator in the causal association between life stressors and well-being. This study aimed to verify correlations among self-reported mindfulness, perceived stress (PS), and subjective well-being (SW) in Brazilian PHPs. We performed a correlational cross-sectional study in a purposive sample of Brazilian PHPs (physicians, nurses, nursing assistants, and community health workers), working in community-oriented primary care programs (known locally as "Family Health Programs"). We used validated self-reporting instruments: the Mindful Attention Awareness Scale (MAAS), the Perceived Stress Scale (PSS), and the Subjective Well-being Scale (SWS). We performed a multivariate analysis of variance (MANOVA), through regression coefficients (beta) in relation to the professional category (nursing assistant), in addition to the length of time in the same job (under than 6 months) that had indicated the lowest level of PS. Participants (n=450) comprised community health workers (65.8%), nursing assistants (18%), registered nurses (10.0%), and doctors (family physicians) (6.0%); 94% were female and 83.1% had worked in the same position for more than one year. MANOVA regression analysis showed differences across professional categories and length of time in the same job position in relation to mindfulness, PS, and SW. Nurses demonstrated lower levels of mindfulness, higher PS, and SW negative affect, as well as lower SW positive affect. Being at work for 1 year or longer showed a clear association with higher PS and lower SW positive affect, and no significance with mindfulness levels. Pearson's coefficient values indicated strong negative correlations between mindfulness and PS, and medium correlations between mindfulness and SW. In this study, there were clear correlations

Sample size determination for mediation analysis of longitudinal data.

Science.gov (United States)

Pan, Haitao; Liu, Suyu; Miao, Danmin; Yuan, Ying

2018-03-27

Sample size planning for longitudinal data is crucial when designing mediation studies because sufficient statistical power is not only required in grant applications and peer-reviewed publications, but is essential to reliable research results. However, sample size determination is not straightforward for mediation analysis of longitudinal design. To facilitate planning the sample size for longitudinal mediation studies with a multilevel mediation model, this article provides the sample size required to achieve 80% power by simulations under various sizes of the mediation effect, within-subject correlations and numbers of repeated measures. The sample size calculation is based on three commonly used mediation tests: Sobel's method, distribution of product method and the bootstrap method. Among the three methods of testing the mediation effects, Sobel's method required the largest sample size to achieve 80% power. Bootstrapping and the distribution of the product method performed similarly and were more powerful than Sobel's method, as reflected by the relatively smaller sample sizes. For all three methods, the sample size required to achieve 80% power depended on the value of the ICC (i.e., within-subject correlation). A larger value of ICC typically required a larger sample size to achieve 80% power. Simulation results also illustrated the advantage of the longitudinal study design. The sample size tables for most encountered scenarios in practice have also been published for convenient use. Extensive simulations study showed that the distribution of the product method and bootstrapping method have superior performance to the Sobel's method, but the product method was recommended to use in practice in terms of less computation time load compared to the bootstrapping method. A R package has been developed for the product method of sample size determination in mediation longitudinal study design.

Correlation of Element Concentration of Cd, Cr, Co and Sc in Sea Water, Fish and Algae Samples from Beach of Lemahabang Muria

International Nuclear Information System (INIS)

Sukirno; Rosidi; Agus Taftazani

2007-01-01

The analysis of Cd, Cr, Co, Sb and Sc element in beach environmental samples Lemahabang Muria in the year 2004 has been carried out by using neutron activation analysis (NAA) method. All of heavy metals from sea water (2.0 μg/l) are obviously lower than the threshold value established by SKRI No 51/2004. From the observed data by Excel application of the correlation value (r) shows that between Cd, Cr, Co, Sb and Sc concentrations from dependent variable of sea water about tree independent variable of kerapu fish, green and brown algae shows a highly positive significant correlation (r > 0.92) except element of Sb was sufficiently positive high (r = 0.66). (author)

Application of the digital image correlation method in the study of cohesive coarse soil deformations

Science.gov (United States)

Kogut, Janusz P.; Tekieli, Marcin

2018-04-01

Non-contact video measurement methods are used to extend the capabilities of standard measurement systems, based on strain gauges or accelerometers. In most cases, they are able to provide more accurate information about the material or construction being tested than traditional sensors, while maintaining a high resolution and measurement stability. With the use of optical methods, it is possible to generate a full field of displacement on the surface of the test sample. The displacement value is the basic (primary) value determined using optical methods, and it is possible to determine the size of the derivative in the form of a sample deformation. This paper presents the application of a non-contact optical method to investigate the deformation of coarse soil material. For this type of soil, it is particularly difficult to obtain basic strength parameters. The use of a non-contact optical method, followed by a digital image correlation (DIC) study of the sample obtained during the tests, effectively completes the description of the behaviour of this type of material.

Public attitudes to the promotion of genomic crop studies in Japan: correlations between genomic literacy, trust, and favourable attitude.

Science.gov (United States)

Ishiyama, Izumi; Tanzawa, Tetsuro; Watanabe, Maiko; Maeda, Tadahiko; Muto, Kaori; Tamakoshi, Akiko; Nagai, Akiko; Yamagata, Zentaro

2012-05-01

This study aimed to assess public attitudes in Japan to the promotion of genomic selection in crop studies and to examine associated factors. We analysed data from a nationwide opinion survey. A total of 4,000 people were selected from the Japanese general population by a stratified two-phase sampling method, and 2,171 people participated by post; this survey asked about the pros and cons of crop-related genomic studies promotion, examined people's scientific literacy in genomics, and investigated factors thought to be related to genomic literacy and attitude. The relationships were examined using logistic regression models stratified by gender. Survey results showed that 50.0% of respondents approved of the promotion of crop-related genomic studies, while 6.7% disapproved. No correlation was found between literacy and attitude towards promotion. Trust in experts, belief in science, an interest in genomic studies and willingness to purchase new products correlated with a positive attitude towards crop-related genomic studies.

Correlates of Cutting Behavior among Sexual Minority Youths and Young Adults

Science.gov (United States)

Walls, N. Eugene; Laser, Julie; Nickels, Sarah J.; Wisneski, Hope

2010-01-01

Using secondary analyses of data from a sample of 265 sexual minority youths, the authors examined correlates of cutting behavior to determine whether patterns are similar to those found in studies of self-injury with community samples of predominately heterosexual youths. The sample consisted of youths who received services at an urban social…

Cleaning the correlation matrix with a denoising autoencoder

OpenAIRE

Hayou, Soufiane

2017-01-01

In this paper, we use an adjusted autoencoder to estimate the true eigenvalues of the population correlation matrix from the sample correlation matrix when the number of samples is small. We show that the model outperforms the Rotational Invariant Estimator (Bouchaud) which is the optimal estimator in the sample eigenvectors basis when the dimension goes to infinity.

Are BMI and Sedentariness Correlated? A Multilevel Study in Children

Directory of Open Access Journals (Sweden)

Thayse Natacha Gomes

2015-07-01

Full Text Available The purpose of this research was to investigate the relationship between body mass index (BMI and sedentariness (Sed in children and to examine the influence of child and school correlates on their variation. The sample comprises 580 children (337 girls, 9–11 years. Sedentariness was assessed with an accelerometer, and BMI was computed. Child- and school-level covariates were analyzed using multilevel models. No significant correlation between Sed and BMI was found. School context explains 5% and 1.5% of the total variance in Sed and BMI, respectively. At the child level, only moderate-to-vigorous physical activity was associated with both Sed (β = −0.02 ± 0.002 and BMI (β = −0.005 ± 0.002. Sleep time is related to Sed (β = −0.42 ± 0.04, while sex (β = 1.97 ± 0.13, biological maturity (β = 1.25 ± 0.07, media in the bedroom (β = 0.26 ± 0.08 and healthy (β = −0.09 ± 0.03 and unhealthy (β = −0.07 ± 0.04 diet scores were associated with BMI. None of the school-level covariates were related to BMI, but access to cafeteria (β = −0.97 ± 0.25, playground equipment (β = −0.67 ± 0.20 and restaurants (β = 0.16 ± 0.08 were related to Sed. In conclusion, Sed and BMI were not correlated. Further, they have different correlates, while children’s traits seem to play more relevant roles in their differences in Sed and BMI than the school milieu. This information should be taken into account when strategies to reduce Sed and BMI are implemented.

Sampling study in milk storage tanks by INAA

International Nuclear Information System (INIS)

Santos, L.G.C.; Nadai Fernandes de, E.A.; Bacchi, M.A.; Tagliaferro, F.S.

2008-01-01

This study investigated the representativeness of samples for assessing chemical elements in milk bulk tanks. Milk samples were collected from a closed tank in a dairy plant and from an open top tank in a dairy farm. Samples were analyzed for chemical elements by instrumental neutron activation analysis (INAA). For both experiments, Br, Ca, Cs, K, Na, Rb and Zn did not present significant differences between samples thereby indicating the appropriateness of the sampling procedure adopted to evaluate the analytes of interest. (author)

The Relationship between Irritable Bowel Syndrome, Depression, Anxiety, and Stress among Sample of Irritable Bowel Patients - Predictive Study

OpenAIRE

Osama Hasan Gaber

2016-01-01

This study aimed to examine the relationship of irritable bowel syndrome, anxiety, depression and stress among a sample of78 IBS patients (Rome III Diagnostic Criteria for Irritable Bowel Syndrome), anxiety symptoms scale, Depression symptoms scale, and stress scale (prepared by the researcher) were used Pearson Correlation Coefficient showed that there are statistically significant relationship between IBS and Anxiety, Depression and Stress (P?=0.01). The Regression and Prediction Coefficien...

[Comparative studies of personal and steady-state sampling for determining dust exposure in different job groups].

Science.gov (United States)

Cherneva, P; Lukanova, R

1994-01-01

The variability of the dust concentration in time and space, as well as the change of worker's place during the working process, define the necessity of introducing personal sampling in the hygiene control practice. However, the laboratory equipment with personal devices is still not sufficient. The aim of this work is to assess the dust exposure of the basic professional groups from the ore- and coal production in Bulgaria by personal sampling in comparative studies of the static ambient sampling used up to now. 63 full-shift investigations of the dust factor were performed on professional groups of miners of the polymetal and coal pits by static ambient devices-[Hygitest production] and personal [from firms "Casella", "Strolein" and "Gilian"] devices, after standardized methods. The results are data processed-by means of logarithmic normal distribution of the relation of the respirable dust concentrations, determined personally and by static ambient sampling. The limits of variation of this correlation are from 0.5 to 4.1 at average geometric value -0.95 and standard geometric deviation-1.8 i.e. both types of sampling are intersubstitutional for the examined groups and sites, as in the underground ores the professional risk of respirable dust is underestimated up to 4 times at static ambient sampling.

Religiousness and preoperative anxiety: a correlational study

OpenAIRE

Aghamohammadi Kalkhoran, Masoomeh; Karimollahi, Mansoureh

2007-01-01

Abstract Background Major life changes are among factors that cause anxiety, and one of these changes is surgery. Emotional reactions to surgery have specific effects on the intensity and velocity as well as the process of physical disease. In addition, they can cause delay in patients recovery. This study is aimed at determining the relationship between religious beliefs and preoperative anxiety. Methods This survey is a correlational study to assess the relationship between religious belief...

Correlation between laser-induced breakdown spectroscopy signal and moisture content

Energy Technology Data Exchange (ETDEWEB)

Liu, Yuan [Townes Laser Institute, CREOL - The College of Optics and Photonics, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816 (United States); Gigant, Lionel [Townes Laser Institute, CREOL - The College of Optics and Photonics, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816 (United States); Universite Bordeaux 1, 351 cours de la Liberation 33405 Talence Cedex (France); Baudelet, Matthieu, E-mail: baudelet@creol.ucf.edu [Townes Laser Institute, CREOL - The College of Optics and Photonics, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816 (United States); Richardson, Martin [Townes Laser Institute, CREOL - The College of Optics and Photonics, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816 (United States)

2012-07-15

The possibility of using Laser-Induced Breakdown Spectroscopy (LIBS) for measuring the moisture content of fresh food samples is studied. The normalized line emission of oxygen is highly correlated with the moisture content of the sample, cheese in our case, and can be used as a moisture marker in situations where oxygen interference from the matrix is not a critical issue. The linear correlation between the oxygen signal and the moisture content in the sample shows great potential for using LIBS as an alternative spectroscopic method for moisture monitoring. - Highlights: Black-Right-Pointing-Pointer Quantitative moisture measurement by LIBS. Black-Right-Pointing-Pointer Use of matrix effects and normalization for physical information on the sample. Black-Right-Pointing-Pointer Use of signal from oxygen and CN radical in air background for moisture measurement.

Parental divorce and adjustment in adulthood: findings from a community sample. The ALSPAC Study Team. Avon Longitudinal Study of Pregnancy and Childhood.

Science.gov (United States)

O'Connor, T G; Thorpe, K; Dunn, J; Golding, J

1999-07-01

The current study examines the link between the experience of divorce in childhood and several indices of adjustment in adulthood in a large community sample of women. Results replicated previous research on the long-term correlation between parental divorce and depression and divorce in adulthood. Results further suggested that parental divorce was associated with a wide range of early risk factors, life course patterns, and several indices of adult adjustment. Regression analyses indicated that the long-term correlation between parental divorce and depression in adulthood is explained by quality of parent-child and parental marital relations (in childhood), concurrent levels of stressful life events and social support, and cohabitation. The long-term association between parental divorce and experiencing a divorce in adulthood was partly mediated through quality of parent-child relations, teenage pregnancy, leaving home before 18 years, and educational attainment.

Study of correlations between photoproduced pairs of charmed particles at Experiment E831/FOCUS

Energy Technology Data Exchange (ETDEWEB)

Castromonte Flores, Cesar Manuel [Brazilian Center for Physics Research, Rio de Janeiro (Brazil)

2008-08-01

The authors present the study of the charm-pair correlations produced in photon-nucleon interactions at $\\langle$E_γ$\\rangle$ = 175 GeV/c, by the Fermilab fixed target experiment E831/FOCUS. The E831/FOCUS experiment produced and reconstructed over one million charm particles. This high statistics allows the reconstruction of more than 7000 charm-pair mesons D$\\bar{D}$, 10 times the statistic of former experiments, and also allows to get, for the first time, about 600 totally reconstructed charm-pairs in the DD_s and DΛ_c channels. They were able to study, with some detail, the kinematical correlations between the charm and anticharm particle forming a pair, in the square transverse momentum (p_T²), azimuthal angle difference (ΔΦ), rapidity difference (Δy) and the charm-pair mass variables. They observe some correlation for the longitudinal momenta, and a significant correlation for the transverse momenta of the charm and anticharm particles. They compare the experimental distributions with theoretical predictions based on the photon-gluon fusion model (PGF), for the production of c$\\bar{c}$ quarks, and the standard Lund hadronization model. These models are implemented by the PYTHIA Monte Carlo event generator. The PYTHIA program allows the inclusion, in the simulation, of non-perturbative effects that have been shown to be important for charm production. In order to compare data and simulation, they have generated two Monte Carlo samples, the first one set to favor the production of D$\\bar{D}$ pairs (MCDD2), and the second one set to favor the production of DD_sand DΛ_c pairs, where each one uses different functions and parameters values for the theoretical models in the simulation. They observe, for the correlation distributions, that the set of parameters used by the MCDD2 model together with the intrinsic transverse momentum (k_$\\perp$) of the partons inside the

[Achondroplasia: a pilot study on the psychosocial and medical features of a sample in Puerto Rico].

Science.gov (United States)

Rodriguez-Gomez, José; Aldarondo, Ariadna; Vidot, Frances; Quiñones, Ana; Rivera, Maily; Cintrón, Eledy; Gonzilez, Natalie; Trujillo, Rodolfo F; Lopez-Cordova, Nanet M; Colón, Natalia

2015-01-01

This study explores the psychological wellbeing of twenty-two (n = 22) adults with achondroplasia. The sample was composed of seven (n = 7) males and fifteen (n = 15) females between the ages of 21 and 75 (mean age = 39.6). Each individual completed four self-administered questionnaires: the Beck Depression Inventory (BDI-l), the Beck Anxiety Inventory (BAI), the Beck Hopelessness Scale (BHS), and Derogatis Symptom Check-list-90-Revisited (SCL-90-R). They also filled out a socio-demographic questionnaire. We found that 31.8% of the sample reported at least one comorbid condition such as, hypertension, diabetes, rheumatoid arthritis, asthma, scoliosis, thyroid problems, neuropathy, psoriasis, gastritis and/or sleep apnea; 32% reported mild to severe depressive symp- toms; 55% reported mild to severe symptoms associated to anxiety and 18% reported mild to severe symptoms associated with hopelessness; 22.7% reported mild to severe symptoms in at least one of the sub-scales in Derogatis Symptom Checklist-90-Revisited (SCL-90-R) particularly the obsessive-compulsive, paranoid and depressive subscales. Chi Square correlations (X2) were made to observe if there was interdependence between the socio-demographic variables and the administered tests. In general, no significant correlations were found between BDI-Il, BAI, BHS, SCL-90-R and civil status, gender, income and age. However, a significant correlation was found between age and the somatization sub-scale of the SCL-90-R (rs = 0.510, p achondroplasia. The development of preventive and cultural sensitive interventions is suggested in order to protect and treat individuals with the condition.

Feasibility of self-sampled dried blood spot and saliva samples sent by mail in a population-based study.

Science.gov (United States)

Sakhi, Amrit Kaur; Bastani, Nasser Ezzatkhah; Ellingjord-Dale, Merete; Gundersen, Thomas Erik; Blomhoff, Rune; Ursin, Giske

2015-04-11

In large epidemiological studies it is often challenging to obtain biological samples. Self-sampling by study participants using dried blood spots (DBS) technique has been suggested to overcome this challenge. DBS is a type of biosampling where blood samples are obtained by a finger-prick lancet, blotted and dried on filter paper. However, the feasibility and efficacy of collecting DBS samples from study participants in large-scale epidemiological studies is not known. The aim of the present study was to test the feasibility and response rate of collecting self-sampled DBS and saliva samples in a population-based study of women above 50 years of age. We determined response proportions, number of phone calls to the study center with questions about sampling, and quality of the DBS. We recruited women through a study conducted within the Norwegian Breast Cancer Screening Program. Invitations, instructions and materials were sent to 4,597 women. The data collection took place over a 3 month period in the spring of 2009. Response proportions for the collection of DBS and saliva samples were 71.0% (3,263) and 70.9% (3,258), respectively. We received 312 phone calls (7% of the 4,597 women) with questions regarding sampling. Of the 3,263 individuals that returned DBS cards, 3,038 (93.1%) had been packaged and shipped according to instructions. A total of 3,032 DBS samples were sufficient for at least one biomarker analysis (i.e. 92.9% of DBS samples received by the laboratory). 2,418 (74.1%) of the DBS cards received by the laboratory were filled with blood according to the instructions (i.e. 10 completely filled spots with up to 7 punches per spot for up to 70 separate analyses). To assess the quality of the samples, we selected and measured two biomarkers (carotenoids and vitamin D). The biomarker levels were consistent with previous reports. Collecting self-sampled DBS and saliva samples through the postal services provides a low cost, effective and feasible

The Yoruba version of the Beck Hopelessness Scale: psychometric characteristics and correlates of hopelessness in a sample of Nigerian psychiatric outpatients.

Science.gov (United States)

Aloba, Olutayo; Akinsulore, Adesanmi; Mapayi, Boladale; Oloniniyi, Ibiduniyi; Mosaku, Kolawole; Alimi, Taiwo; Esan, Olufemi

2015-01-01

Previous studies from the developed western countries have repeatedly demonstrated that hopelessness positively correlates with an increased risk of suicide in the context of chronic mental disorders such as schizophrenia and affective disorders. Despite this persistently strong association, the construct of hopelessness in terms of its factorial structure and correlates has not been explored among Nigerian psychiatric outpatients. The aim of this present study is to examine the psychometric characteristics of the Yoruba language culturally adapted version of the Beck Hopelessness Scale in a cross-sectional sample of psychiatric outpatients in South-western Nigeria. The participants were 327 Nigerian adult outpatients receiving treatment for schizophrenia, bipolar and depressive disorders, consecutively recruited from the outpatient psychiatric clinics of a university teaching hospital in South-western Nigeria. The outpatients were recruited over a one year period. They completed the Yoruba translated version of the Beck Hopelessness Scale (BHS-Y), a sociodemographic and illness-related questionnaire, the Beck Depression Inventory-II (BDI-II). Their level of functioning was assessed with the Global Assessment of Functioning Scale (GAF), psychopathology was evaluated with the Positive and Negative Syndrome Scale (PANSS) and the level of disability measured with the World Health Organization Disability Assessment Schedule (WHODAS-II). Suicidality and confirmation of the diagnoses of schizophrenia, bipolar and depressive disorders were evaluated with the Mini International Neuropsychiatric Interview (MINI). The construct of hopelessness in terms of factorial structure, reliability, validity and correlates was explored. Exploratory Factor Analysis using Principal Component Analysis with Varimax rotation was used to examine the factorial structure of the BHS-Y. Internal consistency was examined with Cronbach's alpha, and the construct validity of the scale was assessed

Hope and spirituality among patients with chronic kidney disease undergoing hemodialysis: a correlational study

Directory of Open Access Journals (Sweden)

Ana Carolina Ottaviani

2014-04-01

Full Text Available OBJECTIVE: to analyze the relationship between the hope and spirituality of patients with chronic kidney disease undergoing hemodialysis.METHOD: this is a cross-sectional, correlational study. The sample was composed of 127 patients of a Renal Replacement Unit. Data were collected through individual interviews guided by the following instruments: participant characterization, Herth Hope Index (HHI, and Pinto Pais-Ribeiro Spirituality Scale (PP-RSS.RESULTS: the average HHI score was 38.06 (±4.32 while the average PP-RSS score was 3.67 (±0.62 for "beliefs" and 3.21 (±0.53 for "hope/optimism". Spearman's coefficient indicated there was a moderate positive correlation between the HHI and PP-RSS dimensions of "beliefs" (r=0.430; p<0.001 and "hope/optimism" (r=0.376; p<0.001.CONCLUSION: Since a relationship between the sense of hope and spirituality of patients with chronic kidney disease was found, these constructs should be taken into account at the time health professionals deliver care to help patients coping with the disease and treatment.

Prevalence study of compulsive buying in a sample with low individual monthly income

Directory of Open Access Journals (Sweden)

Priscilla Lourenço Leite

2015-12-01

Full Text Available Introduction: Compulsive buying can be characterized as an almost irresistible impulse to acquire various items. This is a current issue and the prevalence rate in the global population is around 5 to 8%. Some surveys indicate that the problem is growing in young and low-income populations. Objectives: To evaluate the prevalence of compulsive buying among people with low personal monthly incomes and analyze relationships with socio-demographic data. Methods: The Compulsive Buying Scale was administered to screen for compulsive buying and the Hospital Anxiety and Depression Scale was used to assess anxiety and depression in a sample of 56 participants. Pearson coefficients were used to test for correlations. Results: The results indicated that 44.6% presented an average family income equal to or greater than 2.76 minimum wages. It is possible that compulsive buying is not linked to the purchasing power since it was found in a low-income population. Conclusion: Despite the small sample, the results of this study are important for understanding the problem in question.

Serial-data correlator/code translator

Science.gov (United States)

Morgan, L. E.

1977-01-01

System, consisting of sampling flip flop, memory (either RAM or ROM), and memory buffer, correlates sampled data with predetermined acceptance code patterns, translates acceptable code patterns to nonreturn-to-zero code, and identifies data dropouts.

Analytical Raman spectroscopic study for discriminant analysis of different animal-derived feedstuff: Understanding the high correlation between Raman spectroscopy and lipid characteristics.

Science.gov (United States)

Gao, Fei; Xu, Lingzhi; Zhang, Yuejing; Yang, Zengling; Han, Lujia; Liu, Xian

2018-02-01

The objectives of the current study were to explore the correlation between Raman spectroscopy and lipid characteristics and to assess the potential of Raman spectroscopic methods for distinguishing the different sources of animal-originated feed based on lipid characteristics. A total of 105 lipid samples derived from five animal species have been analyzed by gas chromatography (GC) and FT-Raman spectroscopy. High correlations (r 2 >0.94) were found between the characteristic peak ratio of the Raman spectra (1654/1748 and 1654/1445) and the degree of unsaturation of the animal lipids. The results of FT-Raman data combined with chemometrics showed that the fishmeal, poultry, porcine and ruminant (bovine and ovine) MBMs could be well separated based on their lipid spectral characteristics. This study demonstrated that FT-Raman spectroscopy can mostly exhibit the lipid structure specificity of different species of animal-originated feed and can be used to discriminate different animal-originated feed samples. Copyright © 2017. Published by Elsevier Ltd.

Correlative Super-Resolution Microscopy: New Dimensions and New Opportunities.

Science.gov (United States)

Hauser, Meghan; Wojcik, Michal; Kim, Doory; Mahmoudi, Morteza; Li, Wan; Xu, Ke

2017-06-14

Correlative microscopy, the integration of two or more microscopy techniques performed on the same sample, produces results that emphasize the strengths of each technique while offsetting their individual weaknesses. Light microscopy has historically been a central method in correlative microscopy due to its widespread availability, compatibility with hydrated and live biological samples, and excellent molecular specificity through fluorescence labeling. However, conventional light microscopy can only achieve a resolution of ∼300 nm, undercutting its advantages in correlations with higher-resolution methods. The rise of super-resolution microscopy (SRM) over the past decade has drastically improved the resolution of light microscopy to ∼10 nm, thus creating exciting new opportunities and challenges for correlative microscopy. Here we review how these challenges are addressed to effectively correlate SRM with other microscopy techniques, including light microscopy, electron microscopy, cryomicroscopy, atomic force microscopy, and various forms of spectroscopy. Though we emphasize biological studies, we also discuss the application of correlative SRM to materials characterization and single-molecule reactions. Finally, we point out current limitations and discuss possible future improvements and advances. We thus demonstrate how a correlative approach adds new dimensions of information and provides new opportunities in the fast-growing field of SRM.

Stability of DREEM in a Sample of Medical Students: A Prospective Study

Directory of Open Access Journals (Sweden)

Muhamad Saiful Bahri Yusoff

2012-01-01

Full Text Available Background. Over the last 15 year, DREEM was applied in various educational settings to appraise educational climate. So far, none of article reported its stability in Malaysian medical students. Objective. To determine stability of the DREEM to measure educational climate at different time and occasions using a sample of medical students. Methodology. A prospective cohort study was done on 196 first year medical students. It was administered to the medical students at four different intervals. The Cronbach's alpha and intraclass correlation analysis were applied to measure internal consistency and agreement level across the intervals. The analysis was done using SPSS 18. Result. A total of 186 (94.9% medical students responded completely to the DREEM inventory. The overall Cronbach's alpha value of the DREEM at the four measurements ranged between 0.91 and 0.94. The average Cronbach's alpha values of the five subscales ranged between 0.45 and 0.83. The ICC coefficient values for the DREEM total score was 0.67 and its subscales ranged between 0.51 and 0.62. Conclusion. This study supported satisfactory levels of stability and internal consistency of the DREEM to measure educational climate over multiple observations in a sample of Malaysian medical students. Continued research is required to optimise its psychometric credential across educational settings.

Neural correlates of psychological resilience and their relation to life satisfaction in a sample of healthy young adults.

Science.gov (United States)

Kong, Feng; Wang, Xu; Hu, Siyuan; Liu, Jia

2015-12-01

Psychological resilience refers to the ability to thrive in the face of risk and adversity, which is crucial for individuals' mental and physical health. However, its precise neural correlates are still largely unknown. Here we used resting-state functional magnetic resonance imaging (rs-fMRI) to identify the brain regions underlying this construct by correlating individuals' psychological resilience scores with the regional homogeneity (ReHo) and then examined how these resilience-related regions predicted life satisfaction in a sample of healthy young adults. We found that the ReHo in the bilateral insula, right dorsal anterior cingulate cortex (dACC) and right rostral ACC (rACC) negatively predicted individual differences in psychological resilience, revealing the critical role of the salience network (SN) in psychological resilience. Crucially, the ReHo in the dACC within the SN mediated the effects of psychological resilience on life satisfaction. In summary, these findings suggest that spontaneous activity of the human brain reflect the efficiency of psychological resilience and highlight the dACC within the SN as a neural substrate linking psychological resilience and life satisfaction. Copyright © 2015 Elsevier Inc. All rights reserved.

Dynamics and rheology under continuous shear flow studied by x-ray photon correlation spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Fluerasu, Andrei [Brookhaven National Laboratory, NSLS-II, Upton, NY 11973 (United States); Kwasniewski, Pawel; Caronna, Chiara; Madsen, Anders [European Synchrotron Radiation Facility, ID10 (Troika), Grenoble 38043 (France); Destremaut, Fanny; Salmon, Jean-Baptiste [LOF, UMR 5258 CNRS-Rhodia Bordeaux 1, 33608 Pessac (France)], E-mail: fluerasu@bnl.gov

2010-03-15

X-ray photon correlation spectroscopy (XPCS) has emerged as a unique technique allowing the measurement of dynamics of materials on mesoscopic lengthscales. One of the most common problems associated with the use of bright x-ray beams is beam-induced radiation damage, and this is likely to become an even more limiting factor at future synchrotron and free-electron laser sources. Flowing the sample during data acquisition is one of the simplest methods allowing the radiation damage to be limited. In addition to distributing the dose over many different scatterers, the method also enables new functionalities such as time-resolved studies. Here, we further develop a recently proposed experimental technique that combines XPCS and continuously flowing samples. More specifically, we use a model colloidal suspension to show how the macroscopic advective response to flow and the microscopic dissipative dynamics (diffusion) can be quantified from the x-ray data. Our results show very good quantitative agreement with a Poisseuille-flow hydrodynamical model combined with Brownian mechanics. The method has many potential applications, e.g. in the study of dynamics of glasses and gels under continuous shear/flow, protein aggregation processes and the interplay between dynamics and rheology in complex fluids.

Structural neural correlates of multitasking: A voxel-based morphometry study.

Science.gov (United States)

Zhang, Rui-Ting; Yang, Tian-Xiao; Wang, Yi; Sui, Yuxiu; Yao, Jingjing; Zhang, Chen-Yuan; Cheung, Eric F C; Chan, Raymond C K

2016-12-01

Multitasking refers to the ability to organize assorted tasks efficiently in a short period of time, which plays an important role in daily life. However, the structural neural correlates of multitasking performance remain unclear. The present study aimed at exploring the brain regions associated with multitasking performance using global correlation analysis. Twenty-six healthy participants first underwent structural brain scans and then performed the modified Six Element Test, which required participants to attempt six subtasks in 10 min while obeying a specific rule. Voxel-based morphometry of the whole brain was used to detect the structural correlates of multitasking ability. Grey matter volume of the anterior cingulate cortex (ACC) was positively correlated with the overall performance and time monitoring in multitasking. In addition, white matter volume of the anterior thalamic radiation (ATR) was also positively correlated with time monitoring during multitasking. Other related brain regions associated with multitasking included the superior frontal gyrus, the inferior occipital gyrus, the lingual gyrus, and the inferior longitudinal fasciculus. No significant correlation was found between grey matter volume of the prefrontal cortex (Brodmann Area 10) and multitasking performance. Using a global correlation analysis to examine various aspects of multitasking performance, this study provided new insights into the structural neural correlates of multitasking ability. In particular, the ACC was identified as an important brain region that played both a general and a specific time-monitoring role in multitasking, extending the role of the ACC from lesioned populations to healthy populations. The present findings also support the view that the ATR may influence multitasking performance by affecting time-monitoring abilities. © 2016 The Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

Socio-economic correlates of pesticide usage: the case of citrus farmers

International Nuclear Information System (INIS)

Yasin, G.; Aslam, M.; Naz, S.; Parvez, I.

2003-01-01

The socio-economic factors affecting adoption of pesticides on citrus trees in Sargodha Division, Pakistan was studied. Six villages were selected (three from each subdivision) for data collection. Overall 150 orchard owners (25 from each sample village) were interviewed. Data were analyzed using SPSS programme. Gamma test and chi-square were used to check the direction and magnitude of relationship between independent and dependent variables. Among the sample, 48% respondents were spray users. The socio-economic factors that influenced farmer's receptivity to citrus spray were age (negatively correlated), education (positively correlated), social status (positively correlated), farm size (negatively correlated) and farming experience (negatively correlated). By incurring Rs. 3,600.00 per ha on spray farmers received Rs. 19,000.00 as an incremental benefit. Marginal rate of return indicated that by spending Re. 1.00 on spray farmers would get an increase of Rs. 5.27 in their income. (author)

Burnout prevalence and correlates amongst Colombian dental students: the STRESSCODE study.

Science.gov (United States)

Mafla, A C; Villa-Torres, L; Polychronopoulou, A; Polanco, H; Moreno-Juvinao, V; Parra-Galvis, D; Durán, C; Villalobos, M J; Divaris, K

2015-11-01

Accumulating evidence amongst dental students indicates an alarming prevalence of stress, which can precipitate the development of burnout--a state of mental or physical exhaustion and disengagement. Understanding individual and educational correlates of burnout is necessary for its prevention. The aims of this study were to determine the prevalence of burnout amongst a large sample of Colombian dental undergraduates and investigate its psychosocial and educational correlates. Survey data collected from 5647 students participating in the Stress in Colombian Dental Education study were used for this analysis. Burnout was measured using the Maslach Burnout Inventory-Student Survey (MBI-SS). Covariates included participants' socio-demographic characteristics and perceived stress, as well as educational environment factors. Descriptive, bivariate and multivariate methods based on multilevel mixed-effects logistic regression modelling were used for data analysis. Seven per cent of the students surveyed met the criteria for burnout. The prevalence of burnout was higher amongst upper classes, older and married students, those who reported not having passed all required courses and not having dentistry as their first career choice, as well as students in public institutions and those with large class sizes. Moreover, students' perceived stress in the domains of workload and self-efficacy was significantly and positively associated with burnout. Both personal and educational environment characteristics were found to be associated with burnout. Irrespective of these factors, students' perceived stress with regard to workload and self-efficacy was a strong influence on burnout and its alleviation may be a promising avenue to prevent psychological morbidity. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Lunar sample studies

International Nuclear Information System (INIS)

1977-01-01

Lunar samples discussed and the nature of their analyses are: (1) an Apollo 15 breccia which is thoroughly analyzed as to the nature of the mature regolith from which it derived and the time and nature of the lithification process, (2) two Apollo 11 and one Apollo 12 basalts analyzed in terms of chemistry, Cross-Iddings-Pirsson-Washington norms, mineralogy, and petrography, (3) eight Apollo 17 mare basalts, also analyzed in terms of chemistry, Cross-Iddings-Pirsson-Washington norms, mineralogy, and petrography. The first seven are shown to be chemically similar although of two main textural groups; the eighth is seen to be distinct in both chemistry and mineralogy, (4) a troctolitic clast from a Fra Mauro breccia, analyzed and contrasted with other high-temperature lunar mineral assemblages. Two basaltic clasts from the same breccia are shown to have affinities with rock 14053, and (5) the uranium-thorium-lead systematics of three Apollo 16 samples are determined; serious terrestrial-lead contamination of the first two samples is attributed to bandsaw cutting in the lunar curatorial facility

Socio-Economic Status And Birth-Order As Correlates Of Women ...

African Journals Online (AJOL)

This study investigated socio-economic status and birth-order as correlates of women spiritual help-seeking behavior. Five hundred women help-seekers were sampled from 10 spiritual houses within Ibadan metropolis. Their age ranged between 17-70 years. Fifty percent (50 %,) i.e. 250 of the total sample were singles; ...

BACTERIAL PROFILES FOR CHRONIC AND AGGRESSIVE PERIODONTITIS IN A SAMPLE POPULATION GROUP. A CROSS-SECTIONAL STUDY

Directory of Open Access Journals (Sweden)

Alexandra-Cornelia TEODORESCU

2017-06-01

Full Text Available Aim. The study aims at determining some possible significant differences in the subgingival microbial profiles of patients with generalized chronic periodontitis (GCP and generalized aggressive periodontitis (GAP, as a tool in helping with differential diagnostic. Materials and methods. 20 subgingival fluid samples (10 from GAP and 10 from GCP patients were subjected to a Real-Time Polymerase Chain Reaction technique in order to determine the prevalence and the counts of 9 periodontal pathogens (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, Tanerella forsythia, Prevotella intermedia, Peptostreptococcus micros, Fusobacterium nucleatum, Eubacterium nodatum and Capnocytophaga gingivalis. Results and discussion. Fusobacterium nucleatum was singnificantly correlated with the aggressive periodontitis group, but no significant differences were found for the other 8 periodontal bacteria. Conclusions. The prevalence or count of some periodontal pathogens could help clinicians make an easier differential diagnostic between GCP and GAP, however further studies, conducted on larger population samples, are still needed.

[Evaluation of crude drugs by means of colorimeter (I). Study on correlation between color and alkaloids content of coptidis rhizoma].

Science.gov (United States)

Yoshimitsu, Michiyo; Qu, Xian-You; Luo, Wei-Zao; Qin, Song-Yun

2014-05-01

To examine the correlation between alkaloids content and L*, a* and b* color indices of Rhizoma Coptidis for quality control. A colorimeter was used for the measurement of reflected light from sieved powder samples using the CIE 1976 L* a* b* color system. The content of six alkaloids were determined by HPLC. The correlation between alkaloids content and color indices of Rhizoma Coptidis was analyzed. When the particle size of Rhizoma Coptidis was less than 355 microm and the colorimeter parameters were set as measurement diameter of 3 mm, observation degree of 10, and light source of F2 and F7, the measured color was significantly correlated with total alkaloids content (r = 0.793, P < 0.05). As light source of F11, the measured color was significantly correlated with berberine content (r = 0.867, P < 0.01). The correlation between the color of powdered Coptidis Rhizoma and its alkaloids contents was found in this study. Measurment of the color of Coptidis Rhizoma can be used to assess its quality.

Study of the Effect of Temporal Sampling Frequency on DSCOVR Observations Using the GEOS-5 Nature Run Results. Part II; Cloud Coverage

Science.gov (United States)

Holdaway, Daniel; Yang, Yuekui

2016-01-01

This is the second part of a study on how temporal sampling frequency affects satellite retrievals in support of the Deep Space Climate Observatory (DSCOVR) mission. Continuing from Part 1, which looked at Earth's radiation budget, this paper presents the effect of sampling frequency on DSCOVR-derived cloud fraction. The output from NASA's Goddard Earth Observing System version 5 (GEOS-5) Nature Run is used as the "truth". The effect of temporal resolution on potential DSCOVR observations is assessed by subsampling the full Nature Run data. A set of metrics, including uncertainty and absolute error in the subsampled time series, correlation between the original and the subsamples, and Fourier analysis have been used for this study. Results show that, for a given sampling frequency, the uncertainties in the annual mean cloud fraction of the sunlit half of the Earth are larger over land than over ocean. Analysis of correlation coefficients between the subsamples and the original time series demonstrates that even though sampling at certain longer time intervals may not increase the uncertainty in the mean, the subsampled time series is further and further away from the "truth" as the sampling interval becomes larger and larger. Fourier analysis shows that the simulated DSCOVR cloud fraction has underlying periodical features at certain time intervals, such as 8, 12, and 24 h. If the data is subsampled at these frequencies, the uncertainties in the mean cloud fraction are higher. These results provide helpful insights for the DSCOVR temporal sampling strategy.

Feasibility of self-sampled dried blood spot and saliva samples sent by mail in a population-based study

International Nuclear Information System (INIS)

Sakhi, Amrit Kaur; Bastani, Nasser Ezzatkhah; Ellingjord-Dale, Merete; Gundersen, Thomas Erik; Blomhoff, Rune; Ursin, Giske

2015-01-01

In large epidemiological studies it is often challenging to obtain biological samples. Self-sampling by study participants using dried blood spots (DBS) technique has been suggested to overcome this challenge. DBS is a type of biosampling where blood samples are obtained by a finger-prick lancet, blotted and dried on filter paper. However, the feasibility and efficacy of collecting DBS samples from study participants in large-scale epidemiological studies is not known. The aim of the present study was to test the feasibility and response rate of collecting self-sampled DBS and saliva samples in a population–based study of women above 50 years of age. We determined response proportions, number of phone calls to the study center with questions about sampling, and quality of the DBS. We recruited women through a study conducted within the Norwegian Breast Cancer Screening Program. Invitations, instructions and materials were sent to 4,597 women. The data collection took place over a 3 month period in the spring of 2009. Response proportions for the collection of DBS and saliva samples were 71.0% (3,263) and 70.9% (3,258), respectively. We received 312 phone calls (7% of the 4,597 women) with questions regarding sampling. Of the 3,263 individuals that returned DBS cards, 3,038 (93.1%) had been packaged and shipped according to instructions. A total of 3,032 DBS samples were sufficient for at least one biomarker analysis (i.e. 92.9% of DBS samples received by the laboratory). 2,418 (74.1%) of the DBS cards received by the laboratory were filled with blood according to the instructions (i.e. 10 completely filled spots with up to 7 punches per spot for up to 70 separate analyses). To assess the quality of the samples, we selected and measured two biomarkers (carotenoids and vitamin D). The biomarker levels were consistent with previous reports. Collecting self-sampled DBS and saliva samples through the postal services provides a low cost, effective and feasible

Theoretical studies of strongly correlated fermions

Energy Technology Data Exchange (ETDEWEB)

Logan, D [Institut Max von Laue - Paul Langevin (ILL), 38 - Grenoble (France)

1997-04-01

Strongly correlated fermions are investigated. An understanding of strongly correlated fermions underpins a diverse range of phenomena such as metal-insulator transitions, high-temperature superconductivity, magnetic impurity problems and the properties of heavy-fermion systems, in all of which local moments play an important role. (author).

Determination of the technetium-99m mercaptoacetyltriglycine plasma clearance in children by means of a single blood sample: a multicentre study

International Nuclear Information System (INIS)

Piepsz, A.; Gordon, I.; Hahn, K.; Kolinska, J.; Kotzerke, J.; Sixt, R.

1993-01-01

A multicentree European study was undertaken in order to determine a reasonable algorithm allowing the determination of overall technetium-99m mercaptoacetyltriglycine clearance using a single blood sample. Employing multiple blood sample clearance as a reference method, it was shown that an acceptable estimation of the MAG3 renal clearance could be obtained using a blood sample taken at any time between 30 and 40 min after tracer injection. After correction for body surface area comparison of clearance determined using (a) the single blood sample and (b) the multiple blood samples provided a coefficient of correlation of 0.949 and an SEE of 27 ml/min. This algorithm is valid for clearance values higher than 100 ml/min/1.73 m 2 and for children older than 1 year of age. (orig.)

Correlations among Galaxy Properties from the Sloan Digital Sky Survey

Science.gov (United States)

Li, Zhongmu; Mao, Caiyan

2013-07-01

Galaxies are complex systems with many properties. Correlations among galaxy properties can supply important clues for studying the formation and evolution of galaxies. Using principal component analysis and least-squares fitting, this paper investigates the correlations among galactic parameters involving more properties (color, morphology, stellar population, and absolute magnitude) than previous studies. We use a volume-limited sample (whole sample) of 75,423 galaxies that was selected from the Sloan Digital Sky Survey Data Release 2 and divided into two subsamples (blue and red samples) using a critical color of (g - r) = 0.70 mag. In addition to recovering some previous results, we also obtain some new results. First, all separators for dividing galaxies into two groups can be related via good parameter-first principal component (PC1) correlations. A critical PC1 that indicates whether or not stellar age (or the evolution of a stellar population over time) is important can be used to separate galaxies. This suggests that a statistical parameter, PC1, is helpful in understanding the physical separators of galaxies. In addition, stellar age is shown to be unimportant for red galaxies, while both stellar age and mass are dominating parameters of blue galaxies. This suggests that the various numbers of dominating parameters of galaxies may result from the use of different samples. Finally, some parameters are shown to be correlated, and quantitative fits for a few correlations are obtained, e.g., log(t) = 8.57 + 1.65 (g - r) for the age (log t) and color (g - r) of blue galaxies and log (M *) = 4.31 - 0.30 M r for the stellar mass (log M *) and absolute magnitude (M r) of red galaxies. The median relationships between various parameter pairs are also presented for comparison.

A Comparison of 4- and 24-Hour Urine Samples for the Diagnosis of Proteinuria in Pregnancy

Directory of Open Access Journals (Sweden)

Afsane Amirabi

2011-09-01

Full Text Available Background: Preeclampsia is a serious complication of pregnancy, and it is vital to diagnosis the condition as early as possible. Proteinuria is an important symptom of preeclampsia, and repeated urine analysis to screen for the condition is part of the standard antenatal care. The purpose of this study was to determine the correlation between 4- and 24-hour urine total protein values to examine whether the 4-hour urine samples could be used for the diagnosis of proteinuria in hypertensive disorders of pregnancy. Methods: A cross-sectional study was performed on 110 pregnant (after gestational week 20 of pregnancy patients who were hypertensive (blood pressure ≥140/90 mmHg and had proteinuria as defined by positive urinary protein of at least 1+ in dipstick. Patients' urine samples were collected over 24 hours; the first 4 hours were collected separately from the next 20-hours. Patients, who did not collect the 24-hour urine, were excluded from the study. One hundred patients met the criteria, and were included in the study. The urine volume, total protein and creatinine levels of 4- and 24-hours samples were measured. The correlation between 4-hour and 24-hour samples was examined using Pearson correlation test. Results: Of the 100 patients, 42 had no proteinuria, 44 had mild proteinuria, and 14 had severe proteinuria. The urine protein values of 4-hour samples correlated with those of the 24-hours samples for patients with mild and severe forms of the disease (P<0.001, r=0.86. Conclusion: This study showed there was a correlation between 4-hour and 24-hour urine proteins. The finding indicates that a random 4-hour sample might be used for the initial assessment of proteinuria

Sampling challenges in a study examining refugee resettlement.

Science.gov (United States)

Sulaiman-Hill, Cheryl Mr; Thompson, Sandra C

2011-03-15

As almost half of all refugees currently under United Nations protection are from Afghanistan or Iraq and significant numbers have already been resettled outside the region of origin, it is likely that future research will examine their resettlement needs. A number of methodological challenges confront researchers working with culturally and linguistically diverse groups; however, few detailed articles are available to inform other studies. The aim of this paper is to outline challenges with sampling and recruitment of socially invisible refugee groups, describing the method adopted for a mixed methods exploratory study assessing mental health, subjective wellbeing and resettlement perspectives of Afghan and Kurdish refugees living in New Zealand and Australia. Sampling strategies used in previous studies with similar refugee groups were considered before determining the approach to recruitment A snowball approach was adopted for the study, with multiple entry points into the communities being used to choose as wide a range of people as possible to provide further contacts and reduce selection bias. Census data was used to assess the representativeness of the sample. A sample of 193 former refugee participants was recruited in Christchurch (n = 98) and Perth (n = 95), 47% were of Afghan and 53% Kurdish ethnicity. A good gender balance (males 52%, females 48%) was achieved overall, mainly as a result of the sampling method used. Differences in the demographic composition of groups in each location were observed, especially in relation to the length of time spent in a refugee situation and time since arrival, reflecting variations in national humanitarian quota intakes. Although some measures were problematic, Census data comparison to assess reasonable representativeness of the study sample was generally reassuring. Snowball sampling, with multiple initiation points to reduce selection bias, was necessary to locate and identify participants, provide reassurance and

Sampling challenges in a study examining refugee resettlement

Directory of Open Access Journals (Sweden)

Thompson Sandra C

2011-03-01

Full Text Available Abstract Background As almost half of all refugees currently under United Nations protection are from Afghanistan or Iraq and significant numbers have already been resettled outside the region of origin, it is likely that future research will examine their resettlement needs. A number of methodological challenges confront researchers working with culturally and linguistically diverse groups; however, few detailed articles are available to inform other studies. The aim of this paper is to outline challenges with sampling and recruitment of socially invisible refugee groups, describing the method adopted for a mixed methods exploratory study assessing mental health, subjective wellbeing and resettlement perspectives of Afghan and Kurdish refugees living in New Zealand and Australia. Sampling strategies used in previous studies with similar refugee groups were considered before determining the approach to recruitment Methods A snowball approach was adopted for the study, with multiple entry points into the communities being used to choose as wide a range of people as possible to provide further contacts and reduce selection bias. Census data was used to assess the representativeness of the sample. Results A sample of 193 former refugee participants was recruited in Christchurch (n = 98 and Perth (n = 95, 47% were of Afghan and 53% Kurdish ethnicity. A good gender balance (males 52%, females 48% was achieved overall, mainly as a result of the sampling method used. Differences in the demographic composition of groups in each location were observed, especially in relation to the length of time spent in a refugee situation and time since arrival, reflecting variations in national humanitarian quota intakes. Although some measures were problematic, Census data comparison to assess reasonable representativeness of the study sample was generally reassuring. Conclusions Snowball sampling, with multiple initiation points to reduce selection bias, was

Correlation-study about the ambient dose rate and the weather conditions

Science.gov (United States)

Furuya, Masato; Hatano, Yuko; Aoyama, Tomoo; Igarashi, Yasuhito; Kita, Kazuyuki; Ishizuka, Masahide

2016-04-01

The long-term radiation risks are believed to be heavily affected by the resuspension process. We therefore focus on the surface-atmosphere exchange process of released radioactive materials in this study. Radioactive materials were deposited on the soil and float in the air, and such complicated process are influenced by the weather conditions deeply. We need to reveal the correlation between the weather conditions and the ambient dose rate. In this study, we study the correlation between the weather conditions and the ambient dose rate with the correction of the decrease due to the radioactive decay. We found that there is a negative correlation between the ambient dose rate and the soil water content by the correlation coefficient. Using this result, we reconstruct the ambient dose rate from the weather conditions by the multiple regression analysis and found that the reconstructed data agree with the observation very well. Using Kalman filter, which can be sequentially updates the state estimate, we obtained such a good agreement.

Perturbed angular correlation

International Nuclear Information System (INIS)

Fabris, J.D.

1977-01-01

The electric quadrupolar interaction in some hafnium complexes, measured at the metal nucleus level is studied. For that purpose, the technique of γ-γ perturbed angular correlation is used: the frequencies of quadrupolar interaction are compared with some hafnium α-hydroxicarboxilates, namely glycolate, lactate, mandelate and benzylate; the influence of the temperature on the quadrupolar coupling on the hafnium tetramandelate is studied; finally, the effects associated with the capture of thermal neutrons by hafnium tetramandelate are examined locally at the nuclear level. The first group of results shows significant differences in a series of complexes derived from glycolic acid. On the other hand, the substitution of the protons in hafnium tetramandelate structure by some alkaline cations permits to verify a correlation between the variations in the quadrupolar coupling and the electronegativities of the substituent elements. Measurements at high temperatures show that this complex is thermally stable at 100 and 150 0 C. It is possible to see the appearance of two distinct sites for the probe nucleus, after heating the sample at 100 0 C for prolonged time. This fact is attributed to a probable interconversion among the postulated structural isomers for the octacoordinated compounds. Finally, measurements of angular correlation on the irradiated complex show that there is an effective destruction of the target molecule by neutron capture [pt

Alcohol use disorder and divorce: evidence for a genetic correlation in a population-based Swedish sample.

Science.gov (United States)

Salvatore, Jessica E; Larsson Lönn, Sara; Sundquist, Jan; Lichtenstein, Paul; Sundquist, Kristina; Kendler, Kenneth S

2017-04-01

with previous studies. Covariation between AUD and divorce results from overlapping genetic and non-shared environmental factors. Latent genetic and non-shared environmental correlations for alcohol use disorder and divorce are high and moderate. © 2016 Society for the Study of Addiction.

A Bayesian approach shows no correlation between transit-depth and stellar metallicity for confirmed and candidates Kepler gas giants planets

International Nuclear Information System (INIS)

Nehmé, C; Sarkis, P

2017-01-01

Previous study to investigate the correlation between the transit depth and the stellar metallicity of Kepler’s (Q1-Q12) gas giant planets (radii of 5-20R ⊙ ) has led to a weakly significant negative correlation. We use the cumulative catalog of planets detected by the NASA Kepler mission Q1-Q17 catalog, as of April 2015, to perform a solid statistical analysis of this correlation. In the present work, we revise this correlation, within a Bayesian framework, for two large samples: sample A confirmed planets and sample B (confirmed + candidates). We expand a hierarchical method to account for false positives in the studied samples. Our statistical analysis reveals no correlation between the transit depth and the stellar metallicity. This has implications for planet formation theory and interior structure of giant planets. (paper)

Correlates of video games playing among adolescents in an Islamic country

OpenAIRE

Allahverdipour, Hamid; Bazargan, Mohsen; Farhadinasab, Abdollah; Moeini, Babak

2010-01-01

Abstract Background No study has ever explored the prevalence and correlates of video game playing among children in the Islamic Republic of Iran. This study describes patterns and correlates of excessive video game use in a random sample of middle-school students in Iran. Specifically, we examine the relationship between video game playing and psychological well-being, aggressive behaviors, and adolescents' perceived threat of video-computer game playing. Methods This cross-sectional study w...

Sample Size in Qualitative Interview Studies: Guided by Information Power.

Science.gov (United States)

Malterud, Kirsti; Siersma, Volkert Dirk; Guassora, Ann Dorrit

2015-11-27

Sample sizes must be ascertained in qualitative studies like in quantitative studies but not by the same means. The prevailing concept for sample size in qualitative studies is "saturation." Saturation is closely tied to a specific methodology, and the term is inconsistently applied. We propose the concept "information power" to guide adequate sample size for qualitative studies. Information power indicates that the more information the sample holds, relevant for the actual study, the lower amount of participants is needed. We suggest that the size of a sample with sufficient information power depends on (a) the aim of the study, (b) sample specificity, (c) use of established theory, (d) quality of dialogue, and (e) analysis strategy. We present a model where these elements of information and their relevant dimensions are related to information power. Application of this model in the planning and during data collection of a qualitative study is discussed. © The Author(s) 2015.

Correlation of morphological variants of the soft palate and Need's ratio in normal individuals: A digital cephalometric study

Energy Technology Data Exchange (ETDEWEB)

Verma, Pradhuman; Verma, Kanika Gupta; Sachdeva, Suresh K; Juneja, Suruchi [Surendera Dental College and Research Institute, Sriganganagar (India); Kumaraswam; Kikkeri Lakshminarayana [Dept. of Oral Pathology and Microbiology, Farooqia Dental College, Mysore (India); Basavaraju, Suman [Dept. of Periodontics, J.S.S Dental College, Mysore (India)

2014-09-15

The present study was aimed to investigate the variation of soft palate morphology in different age and gender groups. The correlations of radiographic velar length (VL), velar width (VW), pharyngeal depth (PD), and Need's ratio with soft palate variants were also studied in the North Indian subpopulation. The study sample consisted of 300 subjects aged between 15 and 45 (mean: 31.32) years. The velar morphology on lateral cephalograms was examined and grouped into six types. The results obtained were subjected to a statistical analysis to find the correlation between variants of the soft palate with gender and different age groups. The most frequent type of soft palate was leaf shaped (48.7%), and the least common was crook shaped (3.0%) among both the genders and various age groups, showing a significant correlation. The mean VL, VW, and PD values were significantly higher in males and significantly correlated with the types of soft palate. A significant correlation was observed between the mean VL, VW, PD, and Need's ratio with various age groups, showing an inconsistent pattern with an increase in age. The types of soft palate, gender, and Need's ratio were also significantly correlated, with an overall higher mean value of the Need's ratio among female subjects and the S-shaped soft palate. The knowledge of a varied spectrum of velar morphology and the variants of the soft palate help in a better understanding of the velopharyngeal closure and craniofacial anomalies.

Correlation analysis of first phase monitoring results for uranium mill workers

International Nuclear Information System (INIS)

Davis, M.W.

1983-05-01

This report describes the determination of the existence and extent of correlations in data obtained during the first phase study of urinalysis, personal air sampling and lung burden measurements of uranium mill workers. It was shown that uranium excretions in urine as determined from spot urine samples at the end of the shift were correlated with intakes calculated from personal air sampling data at the 90 percent confidence level. When there are large variations in the rate of urine production, the time rate or uranium elimination was shown to be a more reliable indicator of uranium excretion than the uranium concentration in urine. Based on correlations between phantom and subject lung burden measurements in the presence of changing background radiation levels, a comparative lung burden measurement technique was developed. The sensitivity and accuracy of the method represent a significant improvement and the method is as applicable to females as to males

SAMPLING IN EXTERNAL AUDIT - THE MONETARY UNIT SAMPLING METHOD

Directory of Open Access Journals (Sweden)

E. Dascalu

2016-12-01

Full Text Available This article approaches the general issue of diminishing the evidence investigation space in audit activities, by means of sampling techniques, given that in the instance of a significant data volume an exhaustive examination of the assessed popula¬tion is not possible and/or effective. The general perspective of the presentation involves dealing with sampling risk, in essence, the risk that a selected sample may not be representative for the overall population, in correlation with the audit risk model and with the component parts of this model (inherent risk, control risk and non detection risk and highlights the inter-conditionings between these two models.

CORRELATION BETWEEN PENIS LENGTH AND ANTHOPOMETRY OF 5 YEAR OLD CHILDREN

Directory of Open Access Journals (Sweden)

Doddy Kurnia Indrawan

2013-03-01

Full Text Available Short penis still a problem for parents. Penis lenght is associated with  weight and considered abnormal in obese children. The purpose of this study was to find out the correlation between penis length and the anthropometry children aged 5 years. A cross sectional study was conducted, at the Division of Endocrinology, Department of Child Health, Medical Faculty of Udayana University, Sanglah Hospital Denpasar, during October 2010, at TK Sayang Ibu Sanglah Hospital. The calculation of the sample with a correlation coefficient of weight and  height obtained  9 people, taking in consecutive sampling and analyzed  with Pearson’s correlation. The mean body weight was 23.6 (SD 7.70 kg;  mean child height was 108.4 (SD 5.3 cm, and 47.1% were obese. The mean length of the penis was 4.7(SD1.30 cm. The correlation between weight and penis lenght was strong negative (r = -0.876; P = 0.000 and between penis length and height was r = -0.597; P = 0,011.There was a strong negative correlation between body weight and penis length and also negative correlation between penis length and height in kindergarten children. (MEDICINA 2012;43:19-22.

Conservative Sample Size Determination for Repeated Measures Analysis of Covariance.

Science.gov (United States)

Morgan, Timothy M; Case, L Douglas

2013-07-05

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

Angular correlation between IceCube high-energy starting events and starburst sources

Energy Technology Data Exchange (ETDEWEB)

Moharana, Reetanjali; Razzaque, Soebur, E-mail: moharana.reetanjali@mail.huji.ac.il, E-mail: srazzaque@uj.ac.za [Department of Physics, University of Johannesburg, P.O. Box 524, Auckland Park 2006 (South Africa)

2016-12-01

Starburst galaxies and star-forming regions in the Milkyway, with high rate of supernova activities, are candidate sources of high-energy neutrinos. Using a gamma-ray selected sample of these sources we perform statistical analysis of their angular correlation with the four-year sample of high-energy starting events (HESE), detected by the IceCube Neutrino Observatory. We find that the two samples (starburst galaxies and local star-forming regions) are correlated with cosmic neutrinos at ∼ (2–3)σ (pre-trial) significance level, when the full HESE sample with deposited energy ∼> 20 TeV is considered. However when we consider the HESE sample with deposited energy ∼> 60 TeV, which is almost free of atmospheric neutrino and muon backgrounds, the significance of correlation decreased drastically. We perform a similar study for Galactic sources in the 2nd Catalog of Hard Fermi -LAT Sources (2FHL, >50 GeV) catalog as well, obtaining ∼ (2–3)σ (pre-trial) correlation, however the significance of correlation increases with higher cutoff energy in the HESE sample for this case. We also fit available gamma-ray data from these sources using a pp interaction model and calculate expected neutrino fluxes. We find that the expected neutrino fluxes for most of the sources are at least an order of magnitude lower than the fluxes required to produce the HESE neutrinos from these sources. This puts the starburst sources being the origin of the IceCube HESE neutrinos in question.

Gene Expression Correlation for Cancer Diagnosis: A Pilot Study

Directory of Open Access Journals (Sweden)

Binbing Ling

2014-01-01

Full Text Available Poor prognosis for late-stage, high-grade, and recurrent cancers has been motivating cancer researchers to search for more efficient biomarkers to identify the onset of cancer. Recent advances in constructing and dynamically analyzing biomolecular networks for different types of cancer have provided a promising novel strategy to detect tumorigenesis and metastasis. The observation of different biomolecular networks associated with normal and cancerous states led us to hypothesize that correlations for gene expressions could serve as valid indicators of early cancer development. In this pilot study, we tested our hypothesis by examining whether the mRNA expressions of three randomly selected cancer-related genes PIK3C3, PIM3, and PTEN were correlated during cancer progression and the correlation coefficients could be used for cancer diagnosis. Strong correlations (0.68≤r≤1.0 were observed between PIK3C3 and PIM3 in breast cancer, between PIK3C3 and PTEN in breast and ovary cancers, and between PIM3 and PTEN in breast, kidney, liver, and thyroid cancers during disease progression, implicating that the correlations for cancer network gene expressions could serve as a supplement to current clinical biomarkers, such as cancer antigens, for early cancer diagnosis.

Correlation and spectral density measurements by LDA

International Nuclear Information System (INIS)

Pfeifer, H.J.

1986-01-01

The present paper is intended to give a review on the state-of-the art in correlation and spectral density measurements by means of laser Doppler anemometry. As will be shown in detail the most important difference in performing this type of studies is the fact that laser anemometry relies on the presence of particles in the flow serving as flow velocity indicators. This means that, except in heavily seeded flows, the instantaneous velocity can only be sampled at random instants. This calls for new algorithms to calculate estimates of both correlation functions and power spectra. Various possibilities to handle the problem of random sampling have been developed in the past. They are explained from the theoretical point of view and the experimental aspects are detailed as far as they are different from conventional applications of laser anemometry

Correlates of Mental Illness and Wellbeing in Children: Are They the Same? Results From the UK Millennium Cohort Study.

Science.gov (United States)

Patalay, Praveetha; Fitzsimons, Emla

2016-09-01

To investigate a framework of correlates of both mental illness and wellbeing in a large, current, and nationally representative sample of children in the United Kingdom. An ecologic framework of correlates including individual (sociodemographic and human capital), family, social, and wider environmental factors were examined in 12,347 children aged 11 years old from the UK Millennium Cohort Study. Mental illness and wellbeing scores were standardized to allow comparisons, and the variance explained by the different predictors was estimated. Mental illness and wellbeing were weakly correlated in children (r = 0.2), and their correlates were similar in some instances (e.g., family structure, sibling bullying, peer problems) but differed in others (e.g., family income, perceived socioeconomic status, cognitive ability, health status, neighborhood safety). The predictors included in the study explained 47% of the variance in symptoms of mental illness, with social relationships, home environment, parent health, cognitive ability, socioeconomic status, and health factors predicting large amounts of variance. A comparatively lower 26% of the variance in wellbeing was explained by the study variables, with wider environment, social relationships, perceived socioeconomic status, and home environment predicting the most variance. Correlates of children's mental illness and wellbeing are largely distinct, stressing the importance of considering these concepts separately and avoiding their conflation. This study highlights the relevance of these findings for understanding social gradients in mental health through the life course and the conceptualization and development of mental illness and wellbeing in childhood as precursors to lifelong development in these domains. Copyright © 2016 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

Pion Correlations and Resonance Effects in $\\overline{p}p$ Annihilation at Rest

CERN Document Server

Angelopoulos, Angelos; Aslanides, Elie; Backenstoss, Gerhard; Bargassa, P; Behnke, O; Benelli, A; Bertin, V; Blanc, F; Bloch, P; Carlson, P J; Carroll, M; Cawley, E; Chertok, M B; Danielsson, M; Dejardin, M; Derré, J; Ealet, A; Eleftheriadis, C; Faravel, L; Fetscher, W; Fidecaro, Maria; Filipcic, A; Francis, D; Fry, J; Gabathuler, Erwin; Gamet, R; Gerber, H J; Go, A; Haselden, A; Hayman, P J; Henry-Coüannier, F; Hollander, R W; Jon-And, K; Kettle, P R; Kokkas, P; Kreuger, R; Le Gac, R; Leimgruber, F; Mandic, I; Manthos, N; Marel, Gérard; Mikuz, M; Miller, J; Montanet, François; Müller, A; Nakada, Tatsuya; Pagels, B; Papadopoulos, I M; Pavlopoulos, P; Polivka, G; Rickenbach, R; Roberts, B L; Ruf, T; Schäfer, M; Schaller, L A; Schietinger, T; Schopper, A; Tauscher, Ludwig; Thibault, C; Touchard, F; Touramanis, C; van Eijk, C W E; Vlachos, S; Weber, P; Wigger, O; Wolter, M; Zavrtanik, D; Zimmerman, D; Locher, M P; Markushin, V E

1999-01-01

We study pi pi correlations in the exclusive reactions pbarp -> 2 pi sup + 2 pi sup - and pbarp -> 2 pi sup + 2 pi sup -pi sup 0 at rest with complete reconstruction of the kinematics for each event. A new analysis technique has been developed which is model independent. With this new technique, which relies on double-differential distributions, no reference sample is needed to extract the correlation signal. The correlations are studied as a function of the four-pion invariant mass.

Neural correlates of the severity of cocaine, heroin, alcohol, MDMA and cannabis use in polysubstance abusers: a resting-PET brain metabolism study.

Directory of Open Access Journals (Sweden)

Laura Moreno-López

Full Text Available INTRODUCTION: Functional imaging studies of addiction following protracted abstinence have not been systematically conducted to look at the associations between severity of use of different drugs and brain dysfunction. Findings from such studies may be relevant to implement specific interventions for treatment. The aim of this study was to examine the association between resting-state regional brain metabolism (measured with 18F-fluorodeoxyglucose Positron Emission Tomography (FDG-PET and the severity of use of cocaine, heroin, alcohol, MDMA and cannabis in a sample of polysubstance users with prolonged abstinence from all drugs used. METHODS: Our sample consisted of 49 polysubstance users enrolled in residential treatment. We conducted correlation analyses between estimates of use of cocaine, heroin, alcohol, MDMA and cannabis and brain metabolism (BM (using Statistical Parametric Mapping voxel-based (VB whole-brain analyses. In all correlation analyses conducted for each of the drugs we controlled for the co-abuse of the other drugs used. RESULTS: The analysis showed significant negative correlations between severity of heroin, alcohol, MDMA and cannabis use and BM in the dorsolateral prefrontal cortex (DLPFC and temporal cortex. Alcohol use was further associated with lower metabolism in frontal premotor cortex and putamen, and stimulants use with parietal cortex. CONCLUSIONS: Duration of use of different drugs negatively correlated with overlapping regions in the DLPFC, whereas severity of cocaine, heroin and alcohol use selectively impact parietal, temporal, and frontal-premotor/basal ganglia regions respectively. The knowledge of these associations could be useful in the clinical practice since different brain alterations have been associated with different patterns of execution that may affect the rehabilitation of these patients.

Study of correlations of positive and negative charged particles

International Nuclear Information System (INIS)

Takahashi, Y.; Chan, C.H.; Dong, B.L.; Duthie, J.G.; Gregory, J.C.; Hayashi, T.; Yokomi, H.; Christl, M.J.; Derrickson, J.H.; Eby, P.B.; Fountain, W.F.; Parnell, T.A.; Roberts, F.E.; Nagamiya, S.; Dake, S.; Tominaga, T.; Fuki, M.; Iyono, A.; Ogata, T.; Miyamura, O.

1991-01-01

Particle correlations of the central collision events of 32 S + Pb at 200 GeV/AMU have been studied by utilizing a Magnetic-Interferomagnetic-Emulsion-Chamber (MAGIC) detector. Particle angles, momentum, and charge-signs are measured for all produced charged tracks for each event. Two-particle correlation functions, C 2 = dN (vertical strokep 1 - p 2 vertical stroke = q)/dp 1 dp 2 , for (++), (--) and (+-) particles are examined. A source radius around 4 - 6 fm is observed for overall identical particle correlations, while unexpected short-range correlations of unlike-sign pairs are observed in the high rapidity region. An analysis of unlike-sign pairs in terms of resonance decays indicated that a large amount (40% relative to pions) of η or ω mesons (decaying into 3 π), or of scalar iso-scalar σ mesons (decaying into 2 π) would be required to explain some of the data. Multi-particle charge-sign clusters are recognized; however, their 'run-test' and 'conjugate-test' show small deviations from statistical fluctuations. (orig.)

Correlation of impulsivity with self-harm and suicidal attempt: a community study of adolescents in Taiwan.

Science.gov (United States)

Huang, Yu-Hsin; Liu, Hui-Ching; Tsai, Fang-Ju; Sun, Fang-Ju; Huang, Kuo-Yang; Chiu, Yu-Ching; Huang, Yen-Hsun; Huang, Yo-Ping; Liu, Shen-Ing

2017-12-06

The aim of this study was to investigate differences and similarities in risk factors for deliberate self-harm (DSH) and suicidal attempt (SA), and the role of impulsivity among a group of community adolescents. This is a cross-sectional study conducted at high schools in Northern Taiwan. We recruited grade 1 students from 14 high schools. A total of 5879 participants (mean age 16.02 years, female adolescents: 57.7%) completed the online assessment. Participants completed online questionnaires about sociodemographic data, suicidality, history of DSH and SA, depressed mood, self-esteem, social support, family discord, impulsivity (Barratt Impulsiveness Scale Version 11 (BIS-11)) and the use of alcohol, tobacco and illicit drugs. A subsample was interviewed about lifetime SA, and the results were compared with those from the online questionnaires. In our sample, 25% of the students had lifetime DSH and 3.5% had lifetime SA. Two hundred and seventy-two students received face-to-face interviews. The concordance between the online questionnaires and interviews in terms of ascertaining cases of SA was moderate (concordance rate 82.76%; kappa value 0.59). Similar risk factors for DSH/SA among the whole sample included female gender, lower academic performance, depression, substance use (tobacco and alcohol) and low self-esteem. The BIS-11 score was correlated with DSH. Factor 3 score of the BIS-11 (novelty seeking) was correlated with DSH in both boys and girls, whereas factor 2 score (lack of self-control) was correlated with SA in boys. Social support was a protective factor against SA among the female adolescents. Gender modulated the association of impulsivity and DSH/SA. Associations between impulsivity and DSH and SA were particularly strong among boys. Risk factors for DSH and SA were similar, but not identical. Early identification of those at risk and appropriate interventions may be helpful. © Article author(s) (or their employer(s) unless otherwise stated in

Developing Sampling Frame for Case Study: Challenges and Conditions

Science.gov (United States)

Ishak, Noriah Mohd; Abu Bakar, Abu Yazid

2014-01-01

Due to statistical analysis, the issue of random sampling is pertinent to any quantitative study. Unlike quantitative study, the elimination of inferential statistical analysis, allows qualitative researchers to be more creative in dealing with sampling issue. Since results from qualitative study cannot be generalized to the bigger population,…

Correlation of antigen-specific IFN-γ responses of fresh blood samples from Mycobacterium avium subsp. paratuberculosis infected heifers with responses of day-old samples co-cultured with IL-12 or anti-IL-10 antibodies

DEFF Research Database (Denmark)

Mikkelsen, Heidi; Aagaard, Claus; Nielsen, Søren Saxmose

2012-01-01

Paratuberculosis is a chronic infection of the intestine of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). Early stage MAP infection can be detected by measuring cell-mediated immune responses using the interferon gamma (IFN-γ) assay. Whole blood samples are cultured...... to enhance IFN-γ responses of cultures stimulated with Johnin purified protein derivative (PPDj). Here we examined the correlation of IFN-γ production in response to PPDj and 15 recombinant antigens in day-old blood samples from heifers 10–21 months of age from a MAP infected herd with addition of either...... overnight with specific MAP antigens followed by quantification of IFN-γ by ELISA. It is recommended that the time interval from sampling to culture does not exceed eight hours but addition of the co-stimulating cytokine interleukin 12 (IL-12) or anti-IL-10 antibodies to culture have been demonstrated...

Analysis of the impact of data correlation on adaptive sampling in Wireless Sensor Networks

NARCIS (Netherlands)

Masoum, Alireza; Meratnia, Nirvana; Havinga, Paul J.M.

Wireless Sensor Networks (WSNs) are often densely deployed to monitor a physical phenomenon, whose nature often exhibits temporal correlation in sequential readings. Such a dense deployment results in high correlation of sensing data in the space domain. Since WSNs suffer from sever resource

Hadron azimuthal correlations to be studied at CBM setup

International Nuclear Information System (INIS)

Pozdnyakov, V.; Vertogradova, Yu.

2008-01-01

An opportunity of studying hadron azimuthal correlations with the CBM detector (GSI, Germany) is considered. The results include the full simulation of the UrQMD events together with a simplified consideration of the calorimeter near the beam-pipe. The expectations of the correlations are presented. The centrality determination is considered via both the charged particles detected in the tracking system and the energy deposited in the calorimeter. The segmentation of the calorimeter is discussed from the point of view of the determination accuracy of the reaction plane

Correlational study of impacted and non-functional lower third molar position with occurrence of pathologies

Directory of Open Access Journals (Sweden)

Igor Batista Camargo

2016-09-01

Full Text Available Abstract Background Lower third molar (M3 eruption is unpredictable. The purpose of this study was to correlate radiographic position of M3 on a preexistent film with the current clinical, histopathological, and radiographic findings. Methods A retrospective cohort study was performed. The sample was collected from a database of patients covered by Medical Fund of Brazilian Army. Radiographs were obtained a minimum of 5 years prior to the presurgical visit and after their clinical exam. The primary outcome variables were the teeth positions using Pell and Gregory/Winter classifications on panoramic X-rays. Those variables were analyzed at both the beginning (T0 and end of the study (T1. Clinical assessments and histopathological study of the thirds that were extracted were performed only at T1. Correlation between the teeth positions were related to the clinical, histopathological, and radiographic parameters using statistical analysis tests with significance set at p < 0.05. Results Twenty-six patients with 49 M3 were assessed over 10 months. Mean age was 14.92 years at T0 and 21.87 years at T1. The average time between T0 and T1 was 6.77 years. A significant relationship (p = 0.024 was found between the presences of root resorption on the second molar if M3 presented in an IB horizontal position at T1. There was also a significant correlation (p = 0.039 between dental crowding of the anterior lower teeth with IIIB position at T0 and if the patient finished orthodontic treatment without lingual retainers. Conclusions Lower M3 in position IIIB seen in a teenager and IB seen in an adult is more likely to have negative consequences and should be followed closely.

Analysis method of high-order collective-flow correlations based on the concept of correlative degree

International Nuclear Information System (INIS)

Zhang Weigang

2000-01-01

Based on the concept of correlative degree, a new method of high-order collective-flow measurement is constructed, with which azimuthal correlations, correlations of final state transverse momentum magnitude and transverse correlations can be inspected respectively. Using the new method the contributions of the azimuthal correlations of particles distribution and the correlations of transverse momentum magnitude of final state particles to high-order collective-flow correlations are analyzed respectively with 4π experimental events for 1.2 A GeV Ar + BaI 2 collisions at the Bevalac stream chamber. Comparing with the correlations of transverse momentum magnitude, the azimuthal correlations of final state particles distribution dominate high-order collective-flow correlations in experimental samples. The contributions of correlations of transverse momentum magnitude of final state particles not only enhance the strength of the high-order correlations of particle group, but also provide important information for the measurement of the collectivity of collective flow within the more constraint district

Cannabis use and abuse correlates in a homogeneous South ...

African Journals Online (AJOL)

Objective. Worldwide, cannabis is the most widely used illicit substance, and it has been identified as a correlate in schizophrenia samples for poorer symptomatic and functional outcomes in many international studies. The object of this retrospective study was to identify the prevalence of cannabis use/abuse and the ...

[Study on correlation of glucagons, type 2 diabetes and impaired glucose regulation].

Science.gov (United States)

Xu, Tao; Shi, Me; Qiu, Yun-Xia; Wang, Yan-Gang

2014-06-01

To analyze the changes of patients with type 2 diabetes in different stages in glucagon (GC) and free fatty acid (FFA) in fasting, OGT and L-Arg experiments, and discusses the role of pancreatic alphabeta cells in diabetes pathogenesis by studying the relations among indexes such as glucagon (GC), free fatty acid (FFA) and blood glucose (BG), insulin, insulin homeostasis model (HOMA) and glucose metabolism hormone secretion curve, in order to provide theoretical basis for the treatment of diabetes. Study objects were divided into the T2DM group (45 cases), the IGT group (28 cases) and the NGT group (30 cases) for an OGTT experiment and then an L-Arg experiment on the next day. Under the fasting state, their blood glucose (FBG), insulin (F), glucagon (FGC), free fatty acid (FFA) were detected to calculate HOMA-beta, insulin sensitivity index (ISI) and HOMA-IR of different groups. Meanwhile, efforts were made to calculate different time quantum detected in OGTT and L-Arg experiments and area under the curve AUC(BG), AUC(INS) and AUC(GC). Obvious overall differences were observed in FFA and FGC of the three groups. FGC of each group was negatively correlated with HOMA-beta and ISI. Among all of the 103 study objects, FGC was positively correlated with FBG and HOMA-IR and negatively correlated with HOMA-beta and ISI, with no correlation with FINS; FFA was positively correlated with FBG, HOMA-IR and negatively correlated with FINS, HOMA-beta, ISI. FGC and FFA were positively correlated in the T2DM group and the IGT group, but with no statistical correlation in the NGT group. The sequence of the three study objects was T2DM > IGR > NGT in AUC(GC) in the OGTT experiment and T2DM > IGR > NGT in in AUC(GC) in the L-Arg experiment, with the significant positive correlation between AUC(GC) and AUC(BG) and significant negative correlation with AUC(INS). Glucagon and free fatty acid of T2DM and IGT patients increased, which was positively correlated with blood glucose and HOMA

An integrated rock magnetic and EPR study in soil samples from a hydrocarbon prospective area

Science.gov (United States)

González, F.; Aldana, M.; Costanzo-Álvarez, V.; Díaz, M.; Romero, I.

Magnetic susceptibility (MS) and organic matter free radical concentration (OMFRC) determined by electron paramagnetic resonance, have been measured in soil samples (≈1.5 m depth) from an oil prospective area located at the southern flank of the Venezuelan Andean Range. S-ratios close to 1, as well as high temperature susceptibility analyses, reveal magnetite as the chief magnetic phase in most of these samples. Ethane concentrations, MS and OMFRC normalized data have been plotted against the relative position of 22 sampling sites sequentially arranged from north to south. Although there is not a linear correlation between MS and OMFRC data, these two profiles seem to vary in like fashion. A MS and OMFRC southern anomaly coincides with the zone of highest ethane concentration that overlies a “Cretaceous kitchen”. OMFRC highs could be linked to the degradation or alteration of organic matter, the possible result of hydrocarbon gas leakage, whose surface expression is the stressed fern observed by remote sensing studies previously performed in the area. Ethane anomalies are associated to this seepage that also produces changes in the magnetic mineralogies detected as MS positive anomalies.

Results of Self-Absorption Study on the Versapor 3000 Filters for Radioactive Particulate Air Sampling

International Nuclear Information System (INIS)

Barnett, J.M.

2008-01-01

Since the mid-1980s the Pacific Northwest National Laboratory (PNNL) has used a value of 0.85 as a correction factor for the self absorption of activity of particulate radioactive air samples. More recently, an effort was made to evaluate the current particulate radioactive air sample filters (Versapor(reg s ign) 3000) used at PNNL for self absorption effects. There were two methods used in the study, (1) to compare the radioactivity concentration by direct gas-flow proportional counting of the filter to the results obtained after acid digestion of the filter and counting again by gas-flow proportional detection and (2) to evaluate sample filters by high resolution visual/infrared microscopy to determine the depth of material loading on or in the filter fiber material. Sixty samples were selected from the archive for acid digestion in the first method and about 30 samples were selected for high resolution visual/infrared microscopy. Mass loading effects were also considered. From the sample filter analysis, large error is associated with the average self absorption factor, however, when the data is compared directly one-to-one, statistically, there appears to be good correlation between the two analytical methods. The mass loading of filters evaluated was <0.2 mg cm-2 and was also compared against other published results. The microscopy analysis shows the sample material remains on the top of the filter paper and does not imbed into the filter media. Results of the microscopy evaluation lead to the conclusion that there is not a mechanism for significant self absorption. The overall conclusion is that self-absorption is not a significant factor in the analysis of filters used at PNNL for radioactive air stack sampling of radionuclide particulates and that an applied correction factor is conservative in determining overall sample activity. A new self absorption factor of 1.0 is recommended

Behavioural sampling techniques and activity pattern of Indian Pangolin Manis crassicaudata (Mammalia: Manidae in captivity

Directory of Open Access Journals (Sweden)

R.K. Mohapatra

2013-12-01

Full Text Available The study presents data on six Indian Pangolins Manis crassicaudata observed in captivity at the Pangolin Conservation Breeding Centre, Nandankanan, Odisha, India over 1377 hours of video recordings for each pangolin between 1500hr and 0800hr on 81 consecutive observational days. Video recordings were made through digital systems assisted by infrared enabled CCTV cameras. The data highlights patterns relate to 12 different behaviour and enclosure utilization. Different interval periods for sampling of instantaneous behaviour from video recordings have been evaluated to develop optimal study methods for the future. The activity budgets of pangolins displayed natural patterns of nocturnal activity with a peak between 20:00-21:00 hr. When out of their burrow, they spent about 59% of the time walking in the enclosure, and 14% of the time feeding. The repeatability of the behaviours has a significant negative correlation with the mean time spent in that behaviour. Focal behavioural samples significantly correlated with instantaneous samples up to 15 minutes interval. The correlation values gradually decreased with the increase in sampling interval. The results indicate that results obtained from focal sampling and instantaneous sampling with relatively shorter intervals (=5 minutes are about equally reliable. The study suggests use of focal sampling, instead of instantaneous sampling to record behaviour relating to social interactions.

Sampling pig farms at the abattoir in a cross-sectional study − Evaluation of a sampling method

DEFF Research Database (Denmark)

Birkegård, Anna Camilla; Hisham Beshara Halasa, Tariq; Toft, Nils

2017-01-01

slaughter pigs. It was not possible to visit farms within the designated timeframe. Therefore, it was decided to use convenience sampling at the abattoir. Our approach was carried out in three steps: 1) planning: using data from meat inspection to plan at which abattoirs and how many farms to sample; 2......A cross-sectional study design is relatively inexpensive, fast and easy to conduct when compared to other study designs. Careful planning is essential to obtaining a representative sample of the population, and the recommended approach is to use simple random sampling from an exhaustive list...... of units in the target population. This approach is rarely feasible in practice, and other sampling procedures must often be adopted. For example, when slaughter pigs are the target population, sampling the pigs on the slaughter line may be an alternative to on-site sampling at a list of farms. However...

Redshift distortions of galaxy correlation functions

International Nuclear Information System (INIS)

Fry, J.N.; Florida Univ., Gainesville, FL; Gaztanaga, E.; Oxford Univ.

1993-01-01

To examine how peculiar velocities can affect the 2-, 3-, and 4-point correlation functions, we evaluate volume-average correlations for configurations that emphasize and minimize distortions for four different volume-limited samples from each of the CfA, SSRS, and IRAS redshift catalogs. We present the results as the correlation length r 0 and power index γ of the 2-point correlation, anti Ξ 2 = (r 0 /r) γ , and as the hierarchical amplitudes of the 3- and 4-point functions, S 3 = anti Ξ 3 /anti Ξ 2 2 and S 4 = anti Ξ/anti Ξ 2 3 . We find a characteristic distortion for anti Ξ 2 : The slope γ is flatter and the correlation length is larger in redshift space than in real space; that is, redshift distortions ''move'' correlations from small to large scales. At the largest scales, extra power in the redshift distribution is compatible with Ω 4/7 /b ∼ 1; we find 0.53 ± 0.15, 1.10 ± 0.16 and 0.84 ± 0.45 for the CfA, SSRS and IRAS catalogs. Higher order correlations anti Ξ 3 and anti Ξ 4 suffer similar redshift distortions, but in such a way that, within the accuracy of our analysis, the normalized amplitudes S 3 and S 4 are insensitive to this effect. The hierarchical amplitudes S 3 and S 4 are constant as a function of scale between 1-12 h -1 Mpc and have similar values in all samples and catalogues, S 3 ∼ 2 and S 4 ∼ 6, despite the fact that anti Ξ 2 , anti Ξ 3 , and anti Ξ 4 differ from one sample to another by large factors. The agreement between the independent estimations of S 3 and S 4 is remarkable given the different criteria in the selection of galaxies and also the difference in the resulting range of densities, luminosities and locations between samples

Clinical, radiological and molecular diagnosis correlation in serum samples from patients with osteoarticular tuberculosis

Directory of Open Access Journals (Sweden)

Guadalupe García-Elorriaga

2014-07-01

Conclusions: Nested PCR in serum samples is a rapid, highly sensitive and specific modality for OTB detection. PCR should be performed in addition to clinical evaluation, imaging studies, acid-fast bacilli staining, culture and histopathology diagnosis, if possible.

Contributed review: Review of integrated correlative light and electron microscopy.

Science.gov (United States)

Timmermans, F J; Otto, C

2015-01-01

New developments in the field of microscopy enable to acquire increasing amounts of information from large sample areas and at an increased resolution. Depending on the nature of the technique, the information may reveal morphological, structural, chemical, and still other sample characteristics. In research fields, such as cell biology and materials science, there is an increasing demand to correlate these individual levels of information and in this way to obtain a better understanding of sample preparation and specific sample properties. To address this need, integrated systems were developed that combine nanometer resolution electron microscopes with optical microscopes, which produce chemically or label specific information through spectroscopy. The complementary information from electron microscopy and light microscopy presents an opportunity to investigate a broad range of sample properties in a correlated fashion. An important part of correlating the differences in information lies in bridging the different resolution and image contrast features. The trend to analyse samples using multiple correlated microscopes has resulted in a new research field. Current research is focused, for instance, on (a) the investigation of samples with nanometer scale distribution of inorganic and organic materials, (b) live cell analysis combined with electron microscopy, and (c) in situ spectroscopic and electron microscopy analysis of catalytic materials, but more areas will benefit from integrated correlative microscopy.

Contributed Review: Review of integrated correlative light and electron microscopy

International Nuclear Information System (INIS)

Timmermans, F. J.; Otto, C.

2015-01-01

New developments in the field of microscopy enable to acquire increasing amounts of information from large sample areas and at an increased resolution. Depending on the nature of the technique, the information may reveal morphological, structural, chemical, and still other sample characteristics. In research fields, such as cell biology and materials science, there is an increasing demand to correlate these individual levels of information and in this way to obtain a better understanding of sample preparation and specific sample properties. To address this need, integrated systems were developed that combine nanometer resolution electron microscopes with optical microscopes, which produce chemically or label specific information through spectroscopy. The complementary information from electron microscopy and light microscopy presents an opportunity to investigate a broad range of sample properties in a correlated fashion. An important part of correlating the differences in information lies in bridging the different resolution and image contrast features. The trend to analyse samples using multiple correlated microscopes has resulted in a new research field. Current research is focused, for instance, on (a) the investigation of samples with nanometer scale distribution of inorganic and organic materials, (b) live cell analysis combined with electron microscopy, and (c) in situ spectroscopic and electron microscopy analysis of catalytic materials, but more areas will benefit from integrated correlative microscopy

Correlation between Cognitive Functions and Activity of Daily Living among Post-Stroke Patients

Directory of Open Access Journals (Sweden)

Kurniawan Prakoso

2016-09-01

Full Text Available Background: Cognitive impairment is one of the most common post-stroke complications; however, neither patients nor health professionals are often aware of this complication. The impact of cognitive impairment on quality of life is reflected through basic activity daily living (bADL and instrumental activity daily living (IADL. Prior studies concerning the correlation between cognitive impairment and activity daily living has shown contradictive results. This study was conducted in order to analyze the correlation between the cognitive functions and activity daily living in post stroke patients at Dr. Hasan Sadikin General Hospital. Methods: This cross-sectional study was carried out to 23 post-stroke patients from September–November 2015. Samples were collected through consecutive sampling at Dr. Hasan Sadikin General Hospital. Mini Mental State Examination (MMSE was used to assess the cognitive functions and Lawton and Brody Scale to assess both bADL and IADL. Spearman correlation was selected to analyze the existing correlation between each cognitive domain and activity daily living. Results: Spearman statistical correlation showed an insignificant correlation between the cognitive functions and bADL (r2=0.181, p=0.408 and a significant correlation with IADL was obtained (r2=0.517, p=0.03. The only cognitive domain positively correlated with IADL was orientation to time and verbal recall. Conclusions: There is a correlation between cognitive functions and IADL among post-stroke patients at Dr. Hasan Sadikin General Hospital.

Frequency-Modulation Correlation Spectrometer

Science.gov (United States)

Margolis, J. S.; Martonchik, J. V.

1985-01-01

New type of correlation spectrometer eliminates need to shift between two cells, one empty and one containing reference gas. Electrooptical phase modulator sinusoidally shift frequencies of sample transmission spectrum.

The UK Biobank sample handling and storage validation studies.

Science.gov (United States)

Peakman, Tim C; Elliott, Paul

2008-04-01

and aims UK Biobank is a large prospective study in the United Kingdom to investigate the role of genetic factors, environmental exposures and lifestyle in the causes of major diseases of late and middle age. It involves the collection of blood and urine from 500 000 individuals aged between 40 and 69 years. How the samples are collected, processed and stored will have a major impact on the future scientific usefulness of the UK Biobank resource. A series of validation studies was recommended to test the robustness of the draft sample handling and storage protocol. Samples of blood and urine were collected from 40 healthy volunteers and either processed immediately according to the protocol or maintained at specified temperatures (4 degrees C for all tubes with the exception of vacutainers containing acid citrate dextrose that were maintained at 18 degrees C) for 12, 24 or 36 h prior to processing. A further sample was maintained for 24 h at 4 degrees C, processed and the aliquots frozen at -80 degrees C for 20 days and then thawed under controlled conditions. The stability of the samples was compared for the different times in a wide variety of assays. The samples maintained at 4 degrees C were stable for at least 24 h after collection for a wide range of assays. Small but significant changes were observed in metabonomic studies in samples maintained at 4 degrees C for 36 h. There was no degradation of the samples for a range of biochemical assays after short-term freezing and thawing under controlled conditions. Whole blood maintained at 18 degrees C for 24 h in vacutainers containing acid citrate dextrose is suitable for viral immortalization techniques. The validation studies reported in this supplement provide justification for the sample handling and storage procedures adopted in the UK Biobank project.

Statistics and sampling in transuranic studies

International Nuclear Information System (INIS)

Eberhardt, L.L.; Gilbert, R.O.

1980-01-01

The existing data on transuranics in the environment exhibit a remarkably high variability from sample to sample (coefficients of variation of 100% or greater). This chapter stresses the necessity of adequate sample size and suggests various ways to increase sampling efficiency. Objectives in sampling are regarded as being of great importance in making decisions as to sampling methodology. Four different classes of sampling methods are described: (1) descriptive sampling, (2) sampling for spatial pattern, (3) analytical sampling, and (4) sampling for modeling. A number of research needs are identified in the various sampling categories along with several problems that appear to be common to two or more such areas

Correlation studies of neutron multiplicities in the 252Cf spontaneous fission

International Nuclear Information System (INIS)

Alkhazov, I.D.; Dmitriev, V.D.; Kovalenko, S.S.; Kuznetsov, A.V.; Malkin, L.Z.; Petrzhak, K.A.; Petrov, B.F.; Shpakov, V.I.

1988-01-01

Correlations between the numbers of neutrons emitted by the 252 Cf spontaneous fission fragments have been studied as a function of the fragment mass and total kinetic energy. Behaviour of the neutron number dispersions and covariances was studied for the region of symmetric fission. Parameters of the complementary fragment excitation energy distribution (mean values, dispersions, covariances) were determined. Various factors describing correlations between the complementary fragment excitation energies are considered

Regional gray matter correlates of vocational interests.

Science.gov (United States)

Schroeder, David H; Haier, Richard J; Tang, Cheuk Ying

2012-05-16

Previous studies have identified brain areas related to cognitive abilities and personality, respectively. In this exploratory study, we extend the application of modern neuroimaging techniques to another area of individual differences, vocational interests, and relate the results to an earlier study of cognitive abilities salient for vocations. First, we examined the psychometric relationships between vocational interests and abilities in a large sample. The primary relationships between those domains were between Investigative (scientific) interests and general intelligence and between Realistic ("blue-collar") interests and spatial ability. Then, using MRI and voxel-based morphometry, we investigated the relationships between regional gray matter volume and vocational interests. Specific clusters of gray matter were found to be correlated with Investigative and Realistic interests. Overlap analyses indicated some common brain areas between the correlates of Investigative interests and general intelligence and between the correlates of Realistic interests and spatial ability. Two of six vocational-interest scales show substantial relationships with regional gray matter volume. The overlap between the brain correlates of these scales and cognitive-ability factors suggest there are relationships between individual differences in brain structure and vocations.

Attention Deficit Hyperactivity Disorder Prevalence and Correlates Pre- and Post-Bariatric Surgery: A Comparative Cross-Sectional Study.

Science.gov (United States)

Nielsen, Friedrich; Georgiadou, Ekaterini; Bartsch, Merle; Langenberg, Svenja; Müller, Astrid; de Zwaan, Martina

2017-01-01

Previous research shows an association between obesity and attention deficit hyperactivity disorder (ADHD). The present study compares pre- and post-bariatric surgery patients using the internationally used Conners' Adult ADHD Rating Scale (CAARS™) to screen for ADHD. Matched samples pre- (N = 120) and post-bariatric surgery (N = 128) were compared using self-rating instruments to assess ADHD-relevant symptomatology, depression, eating-related psychopathology, and BMI. Prevalence of probable ADHD did not differ between groups using the CAARS Index Scale T-scores; however, CAARS subscales Inattention/Memory and Self-Concept showed significantly lower scores in post-surgery patients. All CAARS subscales correlated significantly with each other, with depression and eating-related psychopathology. There was no correlation between ADHD and excess BMI loss in post-surgery patients. The findings suggest that a considerable number of patients before and after bariatric surgery screened positive for ADHD. It can be hypothesized that some core ADHD symptoms improve after surgery. Future studies are warranted to investigate the influence of ADHD on long-term surgery outcomes. © 2017 The Author(s) Published by S. Karger GmbH, Freiburg.

Attention Deficit Hyperactivity Disorder Prevalence and Correlates Pre- and Post-Bariatric Surgery: A Comparative Cross-Sectional Study

Directory of Open Access Journals (Sweden)

Friedrich Nielsen

2017-01-01

Full Text Available Objective: Previous research shows an association between obesity and attention deficit hyperactivity disorder (ADHD. The present study compares pre- and post-bariatric surgery patients using the internationally used Conners' Adult ADHD Rating Scale (CAARS™ to screen for ADHD. Methods: Matched samples pre- (N = 120 and post-bariatric surgery (N = 128 were compared using self-rating instruments to assess ADHD-relevant symptomatology, depression, eating-related psychopathology, and BMI. Results: Prevalence of probable ADHD did not differ between groups using the CAARS Index Scale T-scores; however, CAARS subscales Inattention/Memory and Self-Concept showed significantly lower scores in post-surgery patients. All CAARS subscales correlated significantly with each other, with depression and eating-related psychopathology. There was no correlation between ADHD and excess BMI loss in post-surgery patients. Conclusion: The findings suggest that a considerable number of patients before and after bariatric surgery screened positive for ADHD. It can be hypothesized that some core ADHD symptoms improve after surgery. Future studies are warranted to investigate the influence of ADHD on long-term surgery outcomes.

non-genetic factors and correlation studies in cattle.

African Journals Online (AJOL)

Bivariate and multivariate analyses fitting an animal model, were conducted by means of (ASREML) ... aggregate genetic improvement in beef cattle is most ..... This trend was observed in the present study. .... effects hence the prediction of correlated responses to ... the shape of the growth curve as an animal can be.

Psychosocial correlates of Internet addiction among Jordanian university students.

Science.gov (United States)

Alzayyat, Abdulkarim; Al-Gamal, Ekhlas; Ahmad, Muayyad M

2015-04-01

Internet addiction is a significant international mental health problem among university students. The purpose of the current study was to investigate the correlation of Internet addiction with university students' characteristics in Jordan using a descriptive, correlational, cross-sectional design. The Internet Addiction Test, Beck Depression Inventory, and Multidimensional Scale of Perceived Social Support were administered to a random sample of 587 undergraduate university students. The findings demonstrated that university year level, student age, depression, and family support were significant correlates of Internet addiction. The current study should raise awareness in nurses and other health care providers that Internet addiction is a potential mental health problem for this student population. The findings from the current study will help develop appropriate interventions for these students and inform future research. Copyright 2015, SLACK Incorporated.

Correlates, comorbidities, and suicidal tendencies of problematic game use in a national wide sample of Korean adults.

Science.gov (United States)

Park, Subin; Jeon, Hong Jin; Son, Jung Woo; Kim, Haesoo; Hong, Jin Pyo

2017-01-01

This study aimed to investigate the prevalence, correlates, comorbidities, and suicidal tendencies of problematic game use in a nationally representative sample of Korean adults. Of the 6022 subjects who participated in the 2011 Korean Epidemiologic Catchment Area study and completed the Composite International Diagnostic Interview 2.1, 1397 game users were evaluated for problematic game use using 9-item DSM-5 proposed criteria for Internet gaming disorder. Respondents who responded "yes" to five or more of the nine DSM-5 criteria were considered as problematic game users and the reminders were considered as normal game users. 4.0% (56/1397) of game users were classified as a problematic game user. Problematic game users were more likely to be in younger age group and live in urban area compared with normal game user. Problematic game use was positively associated with several psychiatric disorders including nicotine use disorder, depressive disorder, and anxiety disorder, but not associated with alcohol use disorder and obsessive-compulsive disorder, after adjusting for age, sex, and residential area. Problematic game use was significantly and positively associated with suicide plans, after controlling for psychiatric disorders as well as socio-demographic factors. Problematic game use is relatively prevalent in Korean adult population and highly comorbid with other psychiatric disorders and suicidality. Therefore, preventive strategy for problematic game use is needed for game users who were more likely to be addicted such as young adults in urban area, and mental health screening and appropriate treatment are needed for individuals with problematic game use.

Health correlates of insomnia symptoms and comorbid mental disorders in a nationally representative sample of US adolescents.

Science.gov (United States)

Blank, Madeleine; Zhang, Jihui; Lamers, Femke; Taylor, Adrienne D; Hickie, Ian B; Merikangas, Kathleen R

2015-01-01

To estimate the prevalence and health correlates of insomnia symptoms and their association with comorbid mental disorders in a nationally representative sample of adolescents in the United States. National representative cross-sectional study. Population-based sample from the US adolescents. A total of 6,483 individuals aged between 13–18 y in the National Comorbidity Survey-Adolescent Supplement (NCS-A) with both individual and parental reports of mental health were included in this study. Participants were classified with insomnia symptoms if they reported difficulty initiating sleep, difficulty maintaining sleep, and/or early morning awakening, nearly every day for at least 2 w in the past year. Nearly one-third of adolescents reported insomnia symptoms for at least 2 w during the previous year. Hispanic and black youth were significantly more likely to report insomnia symptoms (42.0% and 41.3%, respectively) than non-Hispanic white youth (30.4%). Adolescents with insomnia symptoms were at a higher risk for all classes of mental disorders {odds ratio [OR] (95% confidence interval [CI]: 3.4 (2.9–4.0)} including mood, anxiety, behavioral, substance use, and eating disorders, suicidality [OR (95% CI): 2.63 (1.34–5.16)], poor perceived mental health [OR (95% CI): 2.01 (1.02–3.96)], chronic medical conditions [OR (95% CI): 1.94 (1.55–2.43)], smoking [OR (95% CI: 2.60 (1.00–6.72)], and obesity [OR (95% CI: 1.46 (1.10–1.93)] than those without insomnia symptoms. Adolescents with insomnia symptoms and comorbid mental disorders manifested even greater rates of these indicators of negative health behaviors and disorders than those with mental disorders alone (P Insomnia symptoms are reported by one-third of adolescents in the general population. Insomnia symptoms, even in the absence of concomitant depression or other mental disorders, are associated with serious health conditions, risk factors, and suicidality. Comorbid mental disorders potentiate the

Correlations of Consumers, Leisure Motivation and Leisure Value with Leisure Benefits ─A Case Study on Taiwan International Orchid Show

OpenAIRE

Wu Yan

2013-01-01

This study aims to discuss the correlations of consumers’ Leisure Motivation and Leisure Value with Leisure Benefits. Leisure Motivation contains the dimensions of Intellectual Factor, Social Factor, Competence-Mastery, and Stimulus-Avoidance; and, Leisure Value covers Product Value, Service Value, and Experience Value. Visitors to Taiwan International Orchid Show are selected as the research samples for the questionnaire survey. Total 600 copies are distributed on site and 488 valid ones are...