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1

Pearson's Correlation Coefficient  

NSDL National Science Digital Library

This tutorial on Pearson's Correlation Coefficient includes the definition, assumptions, and characteristics of r as well as related statistics and hypothesis test procedures. One section instructs users to find correlation in the WINKS software, but those without the software can still use the tutorial. An exercise is given at the end that can be done with any statistical software package.

2

Alternatives to Pearson's and Spearman's Correlation Coefficients  

E-print Network

This article presents several alternatives to Pearson's correlation coefficient and many examples. In the samples where the rank in a discrete variable counts more than the variable values, the mixtures that we propose of Pearson's and Spearman's correlation coefficients give better results.

Florentin Smarandache

2008-05-03

3

The Evolution of Pearson's Correlation Coefficient  

ERIC Educational Resources Information Center

This article describes an activity for developing the notion of association between two quantitative variables. By exploring a collection of scatter plots, the authors propose a nonstandard "intuitive" measure of association; and by examining properties of this measure, they develop the more standard measure, Pearson's Correlation Coefficient. The…

Kader, Gary D.; Franklin, Christine A.

2008-01-01

4

Pearson's Product-Moment Coefficient of Correlation  

NSDL National Science Digital Library

This tutorial, created by Thomas W. MacFarland of Nova Southeastern University, explains the theory and use of Pearson's Product Moment Coefficient of Correlation and demonstrates it with an example on GPA and test scores. Data sets are provided in both SPSS and Minitab code. This is a great resource for anyone looking for a more in-depth study of statistics. This could be used as either a teaching guide for educators or simply further practice for students.

MacFarland, Thomas W.

5

Zero Pearson Coefficient for Strongly Correlated Growing Trees  

E-print Network

We obtained Pearson's coefficient of strongly correlated recursive networks growing by preferential attachment of every new vertex by $m$ edges. We found that the Pearson coefficient is exactly zero in the infinite network limit for the recursive trees ($m=1$). If the number of connections of new vertices exceeds one ($m>1$), then the Pearson coefficient in the infinite networks equals zero only when the degree distribution exponent $\\gamma$ does not exceed 4. We calculated the Pearson coefficient for finite networks and observed a slow, power-law like approach to an infinite network limit. Our findings indicate that Pearson's coefficient strongly depends on size and details of networks, which makes this characteristic virtually useless for quantitative comparison of different networks.

S. N. Dorogovtsev; A. L. Ferreira; A. V. Goltsev; J. F. F. Mendes

2009-11-22

6

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

NASA Astrophysics Data System (ADS)

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 Mar?enko-Pastur distribution.

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

2013-09-01

7

Robustness of Two Formulas to Correct Pearson Correlation for Restriction of Range  

ERIC Educational Resources Information Center

Many research studies involving Pearson correlations are conducted in settings where one of the two variables has a restricted range in the sample. For example, this situation occurs when tests are used for selecting candidates for employment or university admission. Often after selection, there is interest in correlating the selection variable,…

tran, minh

2011-01-01

8

Requirements for a Cocitation Similarity Measure, with Special Reference to Pearson's Correlation Coefficient.  

ERIC Educational Resources Information Center

Criticizes the use of Pearson's correlation coefficient in author cocitation analysis (ACA), a technique used to analyze the intellectual structure of a given scientific field, and sets forth two natural requirements that a similarity measure applied in ACA should satisfy. Uses real and hypothetical data to obtain counterexamples to both…

Ahlgren, Per; Jarneving, Bo; Rousseau, Ronald

2003-01-01

9

Pearson's Correlation between Three Variables; Using Students' Basic Knowledge of Geometry for an Exercise in Mathematical Statistics  

ERIC Educational Resources Information Center

When studying correlations, how do the three bivariate correlation coefficients between three variables relate? After transforming Pearson's correlation coefficient r into a Euclidean distance, undergraduate students can tackle this problem using their secondary school knowledge of geometry (Pythagoras' theorem and similarity of triangles).…

Vos, Pauline

2009-01-01

10

Asymptotic properties of Pearson's rank-variate correlation coefficient under contaminated Gaussian model.  

PubMed

This paper investigates the robustness properties of Pearson's rank-variate correlation coefficient (PRVCC) in scenarios where one channel is corrupted by impulsive noise and the other is impulsive noise-free. As shown in our previous work, these scenarios that frequently encountered in radar and/or sonar, can be well emulated by a particular bivariate contaminated Gaussian model (CGM). Under this CGM, we establish the asymptotic closed forms of the expectation and variance of PRVCC by means of the well known Delta method. To gain a deeper understanding, we also compare PRVCC with two other classical correlation coefficients, i.e., Spearman's rho (SR) and Kendall's tau (KT), in terms of the root mean squared error (RMSE). Monte Carlo simulations not only verify our theoretical findings, but also reveal the advantage of PRVCC by an example of estimating the time delay in the particular impulsive noise environment. PMID:25393286

Ma, Rubao; Xu, Weichao; Zhang, Yun; Ye, Zhongfu

2014-01-01

11

Asymptotic Properties of Pearson's Rank-Variate Correlation Coefficient under Contaminated Gaussian Model  

PubMed Central

This paper investigates the robustness properties of Pearson's rank-variate correlation coefficient (PRVCC) in scenarios where one channel is corrupted by impulsive noise and the other is impulsive noise-free. As shown in our previous work, these scenarios that frequently encountered in radar and/or sonar, can be well emulated by a particular bivariate contaminated Gaussian model (CGM). Under this CGM, we establish the asymptotic closed forms of the expectation and variance of PRVCC by means of the well known Delta method. To gain a deeper understanding, we also compare PRVCC with two other classical correlation coefficients, i.e., Spearman's rho (SR) and Kendall's tau (KT), in terms of the root mean squared error (RMSE). Monte Carlo simulations not only verify our theoretical findings, but also reveal the advantage of PRVCC by an example of estimating the time delay in the particular impulsive noise environment. PMID:25393286

Ma, Rubao; Xu, Weichao; Zhang, Yun; Ye, Zhongfu

2014-01-01

12

SPSS and SAS programs for comparing Pearson correlations and OLS regression coefficients.  

PubMed

Several procedures that use summary data to test hypotheses about Pearson correlations and ordinary least squares regression coefficients have been described in various books and articles. To our knowledge, however, no single resource describes all of the most common tests. Furthermore, many of these tests have not yet been implemented in popular statistical software packages such as SPSS and SAS. In this article, we describe all of the most common tests and provide SPSS and SAS programs to perform them. When they are applicable, our code also computes 100 × (1 - ?)% confidence intervals corresponding to the tests. For testing hypotheses about independent regression coefficients, we demonstrate one method that uses summary data and another that uses raw data (i.e., Potthoff analysis). When the raw data are available, the latter method is preferred, because use of summary data entails some loss of precision due to rounding. PMID:23344734

Weaver, Bruce; Wuensch, Karl L

2013-09-01

13

An Improved Pearson's Correlation Proximity-Based Hierarchical Clustering for Mining Biological Association between Genes  

PubMed Central

Microarray gene expression datasets has concerned great awareness among molecular biologist, statisticians, and computer scientists. Data mining that extracts the hidden and usual information from datasets fails to identify the most significant biological associations between genes. A search made with heuristic for standard biological process measures only the gene expression level, threshold, and response time. Heuristic search identifies and mines the best biological solution, but the association process was not efficiently addressed. To monitor higher rate of expression levels between genes, a hierarchical clustering model was proposed, where the biological association between genes is measured simultaneously using proximity measure of improved Pearson's correlation (PCPHC). Additionally, the Seed Augment algorithm adopts average linkage methods on rows and columns in order to expand a seed PCPHC model into a maximal global PCPHC (GL-PCPHC) model and to identify association between the clusters. Moreover, a GL-PCPHC applies pattern growing method to mine the PCPHC patterns. Compared to existing gene expression analysis, the PCPHC model achieves better performance. Experimental evaluations are conducted for GL-PCPHC model with standard benchmark gene expression datasets extracted from UCI repository and GenBank database in terms of execution time, size of pattern, significance level, biological association efficiency, and pattern quality. PMID:25136661

Booma, P. M.; Prabhakaran, S.; Dhanalakshmi, R.

2014-01-01

14

An automated Pearson's correlation change classification (APC3) approach for GC/MS metabonomic data using total ion chromatograms (TICs).  

PubMed

A fully automated and computationally efficient Pearson's correlation change classification (APC3) approach is proposed and shown to have overall comparable performance with both an average accuracy and an average AUC of 0.89 ± 0.08 but is 3.9 to 7 times faster, easier to use and have low outlier susceptibility in contrast to other dimensional reduction and classification combinations using only the total ion chromatogram (TIC) intensities of GC/MS data. The use of only the TIC permits the possible application of APC3 to other metabonomic data such as LC/MS TICs or NMR spectra. A RapidMiner implementation is available for download at http://padel.nus.edu.sg/software/padelapc3. PMID:23529371

Prakash, Bhaskaran David; Esuvaranathan, Kesavan; Ho, Paul C; Pasikanti, Kishore Kumar; Chan, Eric Chun Yong; Yap, Chun Wei

2013-05-21

15

Variation and pearson correlation coefficients of warner-bratzler shear force measurements within broiler breast fillets  

Technology Transfer Automated Retrieval System (TEKTRAN)

Measurements of texture properties related to tenderness at different locations within deboned broiler breast fillets have been used to validate techniques for texture analysis and establish correlations between different texture evaluation methods. However, it has been demonstrated that meat text...

16

Pearson's meta-analysis 1 Pearson's meta-analysis revisited  

E-print Network

leads to something new that may be better revisited #12;Pearson's meta-analysis 3 Karl Pearson quote Stigler (2008) recounting Karl Pearson's amazing productivity includes this from Stouffer (1958): "YouPearson's meta-analysis 1 Pearson's meta-analysis revisited in a microarray context Art B. Owen

Owen, Art

17

Correlation  

NSDL National Science Digital Library

This chapter will discuss the concept of correlation , which is used in later chapters that will explain the concepts of validity and reliability. Here, the authors introduce the Pearson correlation coefficient, a statistic that is used with ratio

Edwin P. Christmann

2008-11-01

18

Biochemical abnormalities in Pearson syndrome.  

PubMed

Pearson marrow-pancreas syndrome is a multisystem mitochondrial disorder characterized by bone marrow failure and pancreatic insufficiency. Children who survive the severe bone marrow dysfunction in childhood develop Kearns-Sayre syndrome later in life. Here we report on four new cases with this condition and define their biochemical abnormalities. Three out of four patients presented with failure to thrive, with most of them having normal development and head size. All patients had evidence of bone marrow involvement that spontaneously improved in three out of four patients. Unique findings in our patients were acute pancreatitis (one out of four), renal Fanconi syndrome (present in all patients, but symptomatic only in one), and an unusual organic aciduria with 3-hydroxyisobutyric aciduria in one patient. Biochemical analysis indicated low levels of plasma citrulline and arginine, despite low-normal ammonia levels. Regression analysis indicated a significant correlation between each intermediate of the urea cycle and the next, except between ornithine and citrulline. This suggested that the reaction catalyzed by ornithine transcarbamylase (that converts ornithine to citrulline) might not be very efficient in patients with Pearson syndrome. In view of low-normal ammonia levels, we hypothesize that ammonia and carbamylphosphate could be diverted from the urea cycle to the synthesis of nucleotides in patients with Pearson syndrome and possibly other mitochondrial disorders. © 2015 Wiley Periodicals, Inc. PMID:25691415

Crippa, Beatrice Letizia; Leon, Eyby; Calhoun, Amy; Lowichik, Amy; Pasquali, Marzia; Longo, Nicola

2015-03-01

19

Pearson's Functions to Describe FSW Weld Geometry  

SciTech Connect

Friction stir welding (FSW) is a relatively new joining technique particularly for aluminium alloys that are difficult to fusion weld. In this study, the geometry of the weld has been investigated and modelled using Pearson's functions. It has been demonstrated that the Pearson's parameters (mean, standard deviation, skewness, kurtosis and geometric constant) can be used to characterize the weld geometry and the tensile strength of the weld assembly. Pearson's parameters and process parameters are strongly correlated allowing to define a control process procedure for FSW assemblies which make radiographic or ultrasonic controls unnecessary. Finally, an optimisation using a Generalized Gradient Method allows to determine the geometry of the weld which maximises the assembly tensile strength.

Lacombe, D.; Coupard, D.; Tcherniaeff, S. [Arts et Metiers ParisTech, LAMEFIP, Esplanade des Arts et Metiers, 33405 Talence Cedex (France); Girot, F. [IKERBASQUE, Basque Foundation for Science, Bilbao (Spain); Gutierrez-Orrantia, M. E.

2011-01-17

20

Parental Socio-Economic Status as Correlate of Child Labour in Ile-Ife, Nigeria  

ERIC Educational Resources Information Center

This study investigated the relationship between parental socio-economic status and child labour practices in Ile-Ife, Nigeria. The study employed survey method to gather data from 200 parents which constituted the study population. Pearson Product Moment Correlation and t-test statistics were used for the data analyses. The outcome of the study…

Elegbeleye, O. S.; Olasupo, M. O.

2012-01-01

21

Single Sample t-test  

NSDL National Science Digital Library

This tutorial on the "One Sample t-Test" includes its definition, assumptions, hypotheses, and results. An example using output from the WINKS software is given, but those without the software can still use the tutorial. An exercise is given at the end that can be done with any statistical software package.

22

Fast computation of voxel-level brain connectivity maps from resting-state functional MRI using l?-norm as approximation of Pearson's temporal correlation: proof-of-concept and example vector hardware implementation.  

PubMed

An outstanding issue in graph-based analysis of resting-state functional MRI is choice of network nodes. Individual consideration of entire brain voxels may represent a less biased approach than parcellating the cortex according to pre-determined atlases, but entails establishing connectedness for 1(9)-1(11) links, with often prohibitive computational cost. Using a representative Human Connectome Project dataset, we show that, following appropriate time-series normalization, it may be possible to accelerate connectivity determination replacing Pearson correlation with l1-norm. Even though the adjacency matrices derived from correlation coefficients and l1-norms are not identical, their similarity is high. Further, we describe and provide in full an example vector hardware implementation of l1-norm on an array of 4096 zero instruction-set processors. Calculation times <1000 s are attainable, removing the major deterrent to voxel-based resting-sate network mapping and revealing fine-grained node degree heterogeneity. L1-norm should be given consideration as a substitute for correlation in very high-density resting-state functional connectivity analyses. PMID:25023958

Minati, Ludovico; Zacà, Domenico; D'Incerti, Ludovico; Jovicich, Jorge

2014-09-01

23

GRAPHICS SUBROUTINE LIBRARY T. J. Pearson  

E-print Network

PGPLOT GRAPHICS SUBROUTINE LIBRARY T. J. Pearson June 1989 California Institute of Technology for improvements, to the author: Tim Pearson, Astronomy Department, Caltech 105--24, Pasadena 91125, USA. Telephone

Readhead, Anthony

24

Recent Results in Symmetry Breaking Justin Pearson  

E-print Network

Recent Results in Symmetry Breaking Justin Pearson Uppsala University May 27, 2009 Justin Pearson Andrews), Pascal Van Hentenryck (Brown), Tom Kelsey (St Andrws), Steve Linton (St Andrews), Justin Pearson (Uppsala), Colva M. Roney-Dougal (St Andrews), Meinolf Sellmann (Brown), and Magnus °Agren (Uppsala) Justin

Flener, Pierre

25

Eliot-Pearson Children's School Tufts University  

E-print Network

Eliot-Pearson Children's School Tufts University 105 College Ave Medford, MA 02155 epcs@tufts.edu ph 617-627-3434 fx 617-627-2630 Place: Eliot-Pearson Children's School, Tufts University 105 College Ave. Medford, MA 617-627-3434 Session 1 June 16th ­ July 3rd. Session 2 July 7th ­ July 24th ELIOT-PEARSON

Dennett, Daniel

26

Vectors and Coordinate Copyright 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.  

E-print Network

Chapter 3: Vectors and Coordinate Systems Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley. Systems Coordinate Systems · Used to describe the position of a point in space and labels ­ instructions on how to label a point relative to the origin Copyright © 2008 Pearson Education

Dhamala, Mukesh

27

2015 Pearson Education, Inc. Chapter 6 Atmospheric and Oceanic  

E-print Network

© 2015 Pearson Education, Inc. Chapter 6 Atmospheric and Oceanic Circulations #12;© 2015 Pearson thermohaline circulation. #12;© 2015 Pearson Education, Inc. Eruption of Mount Pinatubo #12;© 2015 Pearson-pressure systems. · Tertiary circulation includes local winds and temporal weather patterns. #12;© 2015 Pearson

Pan, Feifei

28

2015 Pearson Education, Inc. Chapter 7 Water and Atmospheric Moisture  

E-print Network

© 2015 Pearson Education, Inc. Chapter 7 Water and Atmospheric Moisture #12;© 2015 Pearson the major cloud classes and types, including fog. #12;© 2015 Pearson Education, Inc. Something about Water;© 2015 Pearson Education, Inc. Water on Earth Water covers 71% of Earth by area. #12;© 2015 Pearson

Pan, Feifei

29

Drew Pearson's Washington Merry-Go-Round  

NSDL National Science Digital Library

The name Drew Pearson might not be well known today to most people, but from the early 1930s until 1969, he wrote the highly influential (and controversial) syndicated column, "Washington Merry-Go-Round". The column served a muck-racking function for the highest levels of government in the United States. During his long tenure, Pearson wrote on the subject of unscrupulous public officials and became known for his flair for the dramatic. During his long career, Pearson also wrote ten books, including "U.S.A.: Second Class Power?" This excellent collection from American University brings together many of his columns from 1932 to 1969, along with a biography of Pearson and a bibliography of related works. Visitors should feel free to dive right in, and they can also browse by titles and dates.

30

Bayesian Estimation Supersedes the "t" Test  

ERIC Educational Resources Information Center

Bayesian estimation for 2 groups provides complete distributions of credible values for the effect size, group means and their difference, standard deviations and their difference, and the normality of the data. The method handles outliers. The decision rule can accept the null value (unlike traditional "t" tests) when certainty in the estimate is…

Kruschke, John K.

2013-01-01

31

The One-Sample t Test  

NSDL National Science Digital Library

This section, part of a larger site produced by the School of Psychology at the University of New England, focuses on "Common Statistical Tests" using an example on faculty publications to show users how to perform a one-sample t test. Additionally, there is a discussion that includes one-tailed and two-tailed tests.

Price, Ian

32

Karl Pearson's meta-analysis revisited Art B. Owen  

E-print Network

Karl Pearson's meta-analysis revisited Art B. Owen Department of Statistics Sequoia Hall 390 Serra: This paper revisits a meta-analysis method proposed by Pearson (1934) and first used by David (1933 that the method Birnbaum analyzed is not the one that Pearson proposed. We show that Pearson's proposal

Owen, Art

33

2005 Pearson Education Inc., publishing as Addison-Wesley  

E-print Network

© 2005 Pearson Education Inc., publishing as Addison-Wesley History of Astronomy #12;© 2005 Pearson ·predicting eclipses ·and more... Ancient Astronomy #12;© 2005 Pearson Education Inc., publishing as Addison planets' orbits around the Sun #12;© 2005 Pearson Education Inc., publishing as Addison-Wesley #12;© 2005

Shirley, Yancy

34

2015 Pearson Education, Inc. Chapter 1. Essentials of Geography  

E-print Network

© 2015 Pearson Education, Inc. Chapter 1. Essentials of Geography #12;© 2015 Pearson Education, Inc information systems (GIS)--and explain how these tools are used in geographic analysis. #12;© 2015 Pearson (spatial). #12;© 2015 Pearson Education, Inc. What is Spatial? · The term spatial refers to the nature

Pan, Feifei

35

2005 Pearson Education Inc., publishing as Addison-Wesley  

E-print Network

© 2005 Pearson Education Inc., publishing as Addison-Wesley History of Astronomy #12;© 2005 Pearson ·predicting eclipses ·and more... Ancient Astronomy #12;© 2005 Pearson Education Inc., publishing as Addison". #12;© 2005 Pearson Education Inc., publishing as Addison-Wesley Discovering the Universe for Yourself

Shirley, Yancy

36

Come Celebrate With Us Eliot-Pearson's 50th Anniversary  

E-print Network

Come Celebrate With Us Eliot-Pearson's 50th Anniversary as a Department Saturday, October 25th, 2014 Alumni Gatherings Workshops by Eliot-pearson Faculty Lecture by Howard Gardner & a Gala Dinner Scarlett at 617-627-2248 #12;Greetings from Eliot-Pearson! Please join us to celebrate Eliot-Pearson's 50th

Dennett, Daniel

37

NCS Pearson: Scanning the Diet History Questionnaire  

Cancer.gov

NCS Pearson is one source of scannable DHQ forms and scanning services. See Scanning the DHQ for information regarding other sources. Any new information we know of regarding economical printing, scanning, or data entry methods will be posted on this Web site as it becomes available.

38

Sensitivity analysis of Welch's t-test  

NASA Astrophysics Data System (ADS)

Welch t-test is the parametric test for comparing means between two independent groups without assuming equal population variances. This statistic is robust for testing the mean equality when homogeneity assumption is not satisfied, but Welch test is not always robust. When multiple problems such as the distribution is non-normal, variance is heterogeneous and unequal size of groups occur simultaneously, the Type I error will inflate. In this study, various conditions such as sample sizes, type of distributions and unequal group variances were manipulated to investigate on the non robust conditions of Welch test. The Type I error rates and power of the test for different design specifications were obtained and compared. The results indicated that this test did not perform well under non-normal distributions especially when group sizes and unequal group variances are inversely associated or negatively paired. The estimated Type I error inflated as the power of the test improved.

Ahad, Nor Aishah; Yahaya, Sharipah Soaad Syed

2014-07-01

39

2005 Pearson Education Inc., publishing as Addison-Wesley  

E-print Network

© 2005 Pearson Education Inc., publishing as Addison-Wesley Scales of Space and Time #12;© 2005 Pearson Education Inc., publishing as Addison-Wesley A large, glowing ball of gas that generates heat and light through nuclear fusion Star #12;© 2005 Pearson Education Inc., publishing as Addison

Shirley, Yancy

40

2005 Pearson Education Inc., publishing as Addison-Wesley  

E-print Network

© 2005 Pearson Education Inc., publishing as Addison-Wesley Scales of Space and Time #12;© 2005 Pearson Education Inc., publishing as Addison-Wesley Solar (Star) System A star and all the material that orbits it, including its planets and moons #12;© 2005 Pearson Education Inc., publishing as Addison

Shirley, Yancy

41

2005 Pearson Education Inc., publishing as Addison-Wesley  

E-print Network

© 2005 Pearson Education Inc., publishing as Addison-Wesley Scales of Space and Time #12;© 2005 Pearson Education Inc., publishing as Addison-Wesley When we look up at the moon, we are looking into the past... it takes 1 second for light to travel from the Moon to the Earth. #12;© 2005 Pearson Education

Shirley, Yancy

42

James Pearson Duffy Department of Art and Art History James Pearson Duffy Department of Art and Art History  

E-print Network

1 James Pearson Duffy Department of Art and Art History James Pearson Duffy Department of Art and Art History 150 Art Building Detroit, Michigan 48202 Telephone: (313) 577-2980 Fax: (313) 577: (313) 577-2980 Designing the Wild and Cultivating the City The James Pearson Duffy Department of Art

Berdichevsky, Victor

43

The Pearson-Readhead Survey from Space  

NASA Technical Reports Server (NTRS)

The VSOP Space VLBI mission uses the HALCA spacecraft, launched from Japan in February 1997, in conjunction with ground radio observatories around the world to create a high resolution radio-wave length imaging facility. We are using this unique facility to observe a complete sample of Pearson-Readhead Survey sources at 4.8 GHz to determine core brightness temperatures and pc-scale jet properties. The Pearson-Readhead sample has been used for extensive ground-based VLBI survey studies. This sample is ideal for a VSOP survey because the sources are strong, the VSOP u-v coverages are especially good above +350 declination, and multi-epoch ground-based VLBI data and other existing supporting data on these sources exceeds that of any other possible sample. We have chosen to observe a complete subset of this sample that is most likely to show fringes on space-earth baselines. To date we have imaged a majority of the 31 sources in our sample. In addition, we are obtaining matched- resolution 15 GHz observations using the VLBA at epochs close in time to the space VLBI observations to investigate the spectral indices of the source components at high resolution. We gratefully acknowledge the VSOP Project, which is led by the Japanese Institute of Space and Astronautical Science in cooperation with many organizations and radio telescopes around the world. This research was performed in part at the Jet Propulsion Laboratory, California Institute of Technology, under contract to NASA.

Preston, R. A.; Tingay, S. J.; Jones, D. L.; Lister, M.; Piner, G.; Murphy, D. W.; Meier, D. L.; Pearson, T. J.; Readhead, A. C. S.; Hirabayashi, H.; Kobayashi, H.; Inoue, M.

1988-01-01

44

Exam scores by range Copyright 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 3-1  

E-print Network

. However, some of you made huge increases or decreases in your scores. Copyright © 2007 Pearson Education1 Exam scores by range 15 20 25 Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 3-1 0 5 10 85-92 80-85 75-80 70-75 65-70 60-65 55-60 50-55 45-50 0-45 Exam Scores by Grade

Allan, Vicki H.

45

Pearson's Goodness of Fit Statistic as a Score Test Statistic  

E-print Network

Pearson's Goodness of Fit Statistic as a Score Test Statistic Gordon K. Smyth Abstract For any generalized linear model, the Pearson goodness of fit statistic is the score test statistic for testing; exponential family nonlinear model; saturated model. 1 Introduction Goodness of fit tests go back at least

Smyth, Gordon K.

46

2015 Pearson Education, Inc. Chapter 2 Solar Energy to Earth  

E-print Network

© 2015 Pearson Education, Inc. Chapter 2 Solar Energy to Earth and the Seasons #12;© 2015 Pearson of the solar wind. · Explain the characteristics of the electromagnetic spectrum of radiant energy. · Illustrate the interception of solar energy and its uneven distribution at the top of the atmosphere

Pan, Feifei

47

2015 Pearson Education, Inc. Chapter 3 Earth's Modern Atmosphere  

E-print Network

© 2015 Pearson Education, Inc. Chapter 3 Earth's Modern Atmosphere #12;© 2015 Pearson Education, Inc. · Draw a diagram showing atmospheric structure based on three criteria for analysis--composition, temperature, and function. · List and describe the components of the modern atmosphere, giving their relative

Pan, Feifei

48

2005 Pearson Education Inc., publishing as Addison-Wesley  

E-print Network

in the Sky The Circling Sky the rotation of the Earth about its axis day #12;© 2005 Pearson Education Inc The Reason for Seasons the Earth's orbit around the Sun day year What We See When We Look Up #12;© 2005 around the Earth day year month What We See When We Look Up #12;© 2005 Pearson Education Inc., publishing

Shirley, Yancy

49

2005 Pearson Education South Asia Pte Ltd Applied Fluid Mechanics  

E-print Network

. · Identify the fan selection requirements for the system. #12;3 19. Flow of Air in Ducts ©2005 Pearson Education South Asia Pte Ltd Applied Fluid Mechanics 17.Drag and Lift 18.Fans, Blowers, Compressors and the Flow of Gases 19.Flow of Air in Ducts 19. Flow of Air in Ducts ©2005 Pearson Education South Asia Pte

Leu, Tzong-Shyng "Jeremy"

50

On Correlation and Causation David A. Bessler  

E-print Network

and have been obtained via Google Image. Karl Pearson (left) and Francis Galton (right) 1 #12;Correlation. This measure was invented by Galton in the 19th century and used extensively by Pearson in the early 20th from anthropological data," Proceedings of the Royal Society of London 45:135-45. See as well, Pearson

McCarl, Bruce A.

51

Correlation of ADC value with pathologic indexes in colorectal tumor homografts in Balb/c mouse  

PubMed Central

Objective Noninvasive diffusion-weighted magnetic resonance imaging (DWI) is a well-studied MR imaging technique for quantifying water diffusion especially in tumor area. The correlation between apparent diffusion coefficient (ADC) value and apoptosis or proliferation is not clear by now. This study aimed to investigate whether DWI-ADC value could be used as an imaging marker related with pathologic indexes of tumors. Methods A total of 30 Balb/c mice with HT29 colorectal carcinoma were subjected to DWI and histologic analysis. The percentage of ADC changes and the apoptotic and proliferating indexes were calculated at predefined time points. Kolmogorov-Smirnov distances were considered to determine whether the percentage of ADC changes, and the apoptotic and proliferating indexes were normally distributed. An independent-samples t-test was used to analyze the difference between apoptotic and proliferating indexes in the two groups. Results There was a statistically significant difference in proliferating index between the radiotherapy and control groups (mean proliferating index: 49.27% vs. 83.09%), and there was a statistically significant difference in apoptotic index between the two groups (mean apoptotic index: 37.7% vs. 2.71%). A significant positive correlation was found between the percentage of ADC changes of the viable tissue and apoptotic index. Pearson’s correlation coefficient was 0.655 (P=0.015). A significant negative correlation was found between the percentage of ADC changes of the viable tissue and ki-67 proliferation index. Pearson’s correlation coefficient was 0.734 (P<0.001). Conclusions Our results suggest that ADC value may be used in measurement of cell apoptotic and proliferating indexes in colorectal carcinoma. PMID:25232218

Jiang, Hongnan; Niu, Jinliang; Zheng, Ying

2014-01-01

52

DEDICATED TO PROFESSOR V. PAPATHANASIOU Integrated Pearson family and orthogonality of the  

E-print Network

; Derivatives of orthogonal polynomials; Rodrigues polynomials. 1 Introduction Karl Pearson (1895DEDICATED TO PROFESSOR V. PAPATHANASIOU Integrated Pearson family and orthogonality of the Rodrigues polynomials: A review including new results and an alternative classification of the Pearson

Papadatos, Nickos

53

DEDICATED TO PROFESSOR V. PAPATHANASIOU Integrated Pearson family and orthogonality of the  

E-print Network

of distributions; Derivatives of orthogonal polynomials; Rodrigues polynomials. 1 Introduction Karl Pearson (1895DEDICATED TO PROFESSOR V. PAPATHANASIOU Integrated Pearson family and orthogonality of the Rodrigues polynomials: A review including new results and an alternative classification of the Pearson

Papadatos, Nickos

54

17. TYPE F, BUILDING #516730732 PEARSON ROAD, INTERIOR, THIRD FLOOR, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

17. TYPE F, BUILDING #516-730-732 PEARSON ROAD, INTERIOR, THIRD FLOOR, HALLWAY, NORTH VIEW. - Wright-Patterson Air Force Base, Brick Officers' Quarters, Types E & F, Area A, Dayton, Montgomery County, OH

55

13. TYPE F, BUILDING #516730732 PEARSON ROAD, SOUTH REAR, SOUTHWEST ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. TYPE F, BUILDING #516-730-732 PEARSON ROAD, SOUTH REAR, SOUTHWEST CORNER, ROOF AND WALL DETAIL. - Wright-Patterson Air Force Base, Brick Officers' Quarters, Types E & F, Area A, Dayton, Montgomery County, OH

56

18. TYPE F, BUILDING #516732 PEARSON ROAD, INTERIOR, THIRD FLOOR, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

18. TYPE F, BUILDING #516-732 PEARSON ROAD, INTERIOR, THIRD FLOOR, BEDROOM, NORTHWEST VIEW. - Wright-Patterson Air Force Base, Brick Officers' Quarters, Types E & F, Area A, Dayton, Montgomery County, OH

57

15. TYPE F, BUILDING #516732 PEARSON ROAD, INTERIOR, FIRST FLOOR, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. TYPE F, BUILDING #516-732 PEARSON ROAD, INTERIOR, FIRST FLOOR, LIVING ROOM, EAST VIEW. - Wright-Patterson Air Force Base, Brick Officers' Quarters, Types E & F, Area A, Dayton, Montgomery County, OH

58

8. TYPE E, BUILDING #812825 PEARSON ROAD, INTERIOR, SECOND FLOOR, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. TYPE E, BUILDING #812-825 PEARSON ROAD, INTERIOR, SECOND FLOOR, BEDROOM, NORTHWEST VIEW. - Wright-Patterson Air Force Base, Brick Officers' Quarters, Types E & F, Area A, Dayton, Montgomery County, OH

59

6. TYPE E, BUILDING #812825 PEARSON ROAD, INTERIOR, FIRST FLOOR, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. TYPE E, BUILDING #812-825 PEARSON ROAD, INTERIOR, FIRST FLOOR, LIVING ROOM, SOUTHWEST VIEW. - Wright-Patterson Air Force Base, Brick Officers' Quarters, Types E & F, Area A, Dayton, Montgomery County, OH

60

14. TYPE F, BUILDING #516732 PEARSON ROAD, INTERIOR, FIRST FLOOR, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. TYPE F, BUILDING #516-732 PEARSON ROAD, INTERIOR, FIRST FLOOR, DINING ROOM AND HALLWAY, WEST VIEW. - Wright-Patterson Air Force Base, Brick Officers' Quarters, Types E & F, Area A, Dayton, Montgomery County, OH

61

16. TYPE F, BUILDING #516732 PEARSON ROAD, INTERIOR, SECOND FLOOR, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. TYPE F, BUILDING #516-732 PEARSON ROAD, INTERIOR, SECOND FLOOR, HALLWAY, NORTHWEST VIEW. - Wright-Patterson Air Force Base, Brick Officers' Quarters, Types E & F, Area A, Dayton, Montgomery County, OH

62

5. TYPE E, BUILDING #812825 PEARSON ROAD, INTERIOR, FIRST FLOOR, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. TYPE E, BUILDING #812-825 PEARSON ROAD, INTERIOR, FIRST FLOOR, LIVING ROOM, NORTH VIEW. - Wright-Patterson Air Force Base, Brick Officers' Quarters, Types E & F, Area A, Dayton, Montgomery County, OH

63

3. Historic American Buildings Survey, Elmer R. Pearson, Photographer, 1968 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. Historic American Buildings Survey, Elmer R. Pearson, Photographer, 1968 ELEVATION, LOOKING NORTHWEST. - Shaker Centre Family, Broom Shop, East side of Oxford Road, White Water Park, Hamilton County, OH

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1. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Historic American Buildings Survey E. R. Pearson, Photographer 1969 FRONT ELEVATION, LOOKING SOUTH - Shaker Centre Family Ministry's Shop & Dwelling, East side of U.S. Route 68, South Union, Logan County, KY

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18. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

18. Historic American Buildings Survey E. R. Pearson, Photographer 1969 FRONT HALL, FIRST FLOOR, LOOKING NORTH - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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29. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

29. Historic American Buildings Survey E. R. Pearson, Photographer 1972 HALL, FIRST ATTIC, LOOKING SOUTH - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

67

19. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

19. Historic American Buildings Survey E. R. Pearson, Photographer 1969 FRONT HALL, FIRST FLOOR, LOOKING NORTH - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

68

17. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

17. Historic American Buildings Survey E. R. Pearson, Photographer 1969 FRONT HALL, FIRST FLOOR, LOOKING SOUTH - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

69

5. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. Historic American Buildings Survey E. R. Pearson, Photographer 1972 CORNER DETAIL, EAST SIDE, LOOKING SOUTH, MINISTRY'S SHOP IN BACKGROUND - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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15. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. Historic American Buildings Survey E. R. Pearson, Photographer 1972 FOOT SCRAPER, EAST SIDE, LOOKING SOUTH - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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30. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

30. Historic American Buildings Survey E. R. Pearson, Photographer 1972 EAST ROOM, FIRST ATTIC, LOOKING EAST - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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16. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. Historic American Buildings Survey E. R. Pearson, Photographer 1969 FRONT HALL, FIRST FLOOR, LOOKING SOUTH - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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11. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ROOF DETAIL AND STONE GUTTER, EAST SIDE, LOOKING NORTH - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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22. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. Historic American Buildings Survey E. R. Pearson, Photographer 1969 MEETING ROOM, FIRST FLOOR, LOOKING SOUTH - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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4. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. Historic American Buildings Survey E. R. Pearson, Photographer 1969 STONE WALK IN FRONT OF BUILDING - Shaker Centre Family Ministry's Shop & Dwelling, East side of U.S. Route 68, South Union, Logan County, KY

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31. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

31. Historic American Buildings Survey E. R. Pearson, Photographer 1972 CLOTHES ROOM, FIRST ATTIC, SOUTHEAST CORNER, LOOKING EAST - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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32. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

32. Historic American Buildings Survey E. R. Pearson, Photographer 1972 REAR STAIRWAY, NORTH END, LOOKING NORTHEAST - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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23. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

23. Historic American Buildings Survey E. R. Pearson, Photographer 1969 STAIRS AND HALL, SECOND FLOOR, LOOKING SOUTH - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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41. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

41. Historic American Buildings Survey E. R. Pearson, Photographer 1969 THIRD FLOOR AND ATTIC FLOOR PLAN - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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1. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Historic American Buildings Survey E. R. Pearson, Photographer 1969 PRESERVATORY ON LEFT, WASHHOUSE ON RIGHT - Shaker Centre Family Preservatory, West side of U.S. Route 68, South Union, Logan County, KY

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10. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ROOF DETAIL AND STONE GUTTER, EAST SIDE, LOOKING NORTH - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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34. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

34. Historic American Buildings Survey E. R. Pearson, Photographer 1972 KITCHEN WALL, LOOKING SOUTHWEST - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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3. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ENTRANCE STAIRS, LOOKING WEST - Shaker Centre Family Ministry's Shop & Dwelling, East side of U.S. Route 68, South Union, Logan County, KY

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40. Historic American Buildings Survey E. R. Pearson, Photographer January ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

40. Historic American Buildings Survey E. R. Pearson, Photographer January 1970 THIRD FLOOR AND ATTIC FLOOR PLAN - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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13. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. Historic American Buildings Survey E. R. Pearson, Photographer 1972 CORNER DETAIL, EAST SIDE, LOOKING SOUTH, MINISTRY'S SHOP IN BACKGROUND - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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21. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

21. Historic American Buildings Survey E. R. Pearson, Photographer 1969 FRONT HALL, FIRST FLOOR, LOOKING EAST - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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27. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

27. Historic American Buildings Survey E. R. Pearson, Photographer 1972 STAIR RAIL, FIRST ATTIC, LOOKING SOUTHEAST - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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35. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

35. Historic American Buildings Survey E. R. Pearson, Photographer 1972 BAKEROOM, BASEMENT LEVEL, LOOKING WEST - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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20. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

20. Historic American Buildings Survey E. R. Pearson, Photographer 1969 FRONT HALL, FIRST FLOOR, LOOKING NORTH - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

90

14. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. Historic American Buildings Survey E. R. Pearson, Photographer 1972 IRON RAILING, EAST SIDE, LOOKING SOUTHWEST - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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2. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ENTRANCE STAIRS, LOOKING SOUTHWEST - Shaker Centre Family Ministry's Shop & Dwelling, East side of U.S. Route 68, South Union, Logan County, KY

92

24. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

24. Historic American Buildings Survey E. R. Pearson, Photographer 1972 FRONT HALL, SECOND FLOOR, LOOKING NORTH - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

93

12. Historic American Buildings Survey E. R. Pearson, Photographer 1969 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. Historic American Buildings Survey E. R. Pearson, Photographer 1969 SOUTHEAST CORNER DETAIL, LOOKING NORTH - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

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26. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

26. Historic American Buildings Survey E. R. Pearson, Photographer 1972 STAIRS IN FIRST ATTIC HALL TO SECOND ATTIC, LOOKING SOUTHWEST - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

95

Independent Samples t-Test: Chips Ahoy® vs. Supermarket Brand  

NSDL National Science Digital Library

In this hands-on activity, students count the number of chips in cookies in order to carry out an independent samples t-test to compare Chips Ahoy® cookies and a supermarket brand. It can involve discussion of randomness and independence of samples, comparing two parameters with null and alternative hypotheses, and the practical issues of counting chips in a cookie.

Dexter Whittinghill

96

Research Methods Knowledge Base : The t-Test  

NSDL National Science Digital Library

This particular textbook lesson, presented by Cornell University's Research Methods Knowledge Base, addresses the independent t-test. It presents to the user how to compute the t statistic and then how to interpret the results. The site uses graphs and charts along with the text to enhance the presentation. Overall, this is a useful resource for any mathematics classroom.

Trochim, William M.K.

97

Karl Pearson and eugenics: personal opinions and scientific rigor.  

PubMed

The influence of personal opinions and biases on scientific conclusions is a threat to the advancement of knowledge. Expertise and experience does not render one immune to this temptation. In this work, one of the founding fathers of statistics, Karl Pearson, is used as an illustration of how even the most talented among us can produce misleading results when inferences are made without caution or reference to potential bias and other analysis limitations. A study performed by Pearson on British Jewish schoolchildren is examined in light of ethical and professional statistical practice. The methodology used and inferences made by Pearson and his coauthor are sometimes questionable and offer insight into how Pearson's support of eugenics and his own British nationalism could have potentially influenced his often careless and far-fetched inferences. A short background into Pearson's work and beliefs is provided, along with an in-depth examination of the authors' overall experimental design and statistical practices. In addition, portions of the study regarding intelligence and tuberculosis are discussed in more detail, along with historical reactions to their work. PMID:23179067

Delzell, Darcie A P; Poliak, Cathy D

2013-09-01

98

ON PEARSON-VERIFICATION AND THE CHI-SQUARE TEST JOAKIM EKSTROM  

E-print Network

ON PEARSON-VERIFICATION AND THE CHI-SQUARE TEST JOAKIM EKSTR¨OM Abstract. Karl Pearson's seminal empirical observation. 1 #12;2 1. Introduction Karl Pearson was a man who took on a mission to rectify has likely in various ways effected the scientific community negatively. Karl Pearson would

California at Los Angeles, University of

99

Quadrupolar magic angle spinning NMR spectra fitted using the Pearson IV function.  

PubMed

The Pearson IV function was used to fit the asymmetric solid-state (27)Al NMR spectra of alumina based catalysts. A high convergence (correlation coefficient is no less than 0.997) between experimental and simulated spectra was achieved. The decomposition of the (27)Al NMR spectra of zinc/aluminum mixed oxides with different Zn/Al molar ratio revealed an increased fraction (6-9%) of pentacoordinated aluminum atoms in these oxides as compared to ?-Al2O3. As the Zn/Al ratio is raised, the fraction of [AlO6] octahedral units decreases, while the fraction of [AlO4] tetrahedra increases. PMID:25454293

Mironenko, Roman M; Belskaya, Olga B; Talsi, Valentin P; Likholobov, Vladimir A

2014-01-01

100

Chapter 9 Water Resources 2015 Pearson Education, Inc.  

E-print Network

is evapotranspiration (ET)? · Evapotranspiration is a collective term (evaporation + transpiration) for all Bare soil Vegetated evaporation evaporation transpiration uptake evaporation evaporation #12;© 2015 Pearson Education, Inc. Transpiration Capillary rise is the rise in a liquid above the level of zero

Pan, Feifei

101

2015 Pearson Education, Inc. Chapter 5 Global Temperatures  

E-print Network

waves and the heat index as a measure of human heat response, and wind chill index. #12;© 2015 Pearson the molecular motion. · Heat and temperature are related because changes in temperature are caused. Learning Objectives · Define the concept of temperature and heat. · Distinguish between Kelvin, Celsius

Pan, Feifei

102

2015 Pearson Education, Inc. Chapter 4 Atmosphere and Surface Energy  

E-print Network

of albedo (reflectivity). · Analyze the effect of clouds and aerosols on atmospheric heating and cooling sunlight sunlight Refraction and Rainbow #12;© 2015 Pearson Education, Inc. The Greenhouse Effect and Atmospheric Warming · Atmosphere absorbs heat energy. · A real greenhouse traps heat inside. · Atmosphere

Pan, Feifei

103

2005 Pearson Education South Asia Pte Ltd Applied Fluid Mechanics  

E-print Network

and the Flow of Gases 19.Flow of Air in Ducts 18. Fan, Blowers, Compressors and the Flow of Gases ©2005 Pearson. Classification of Fans, Blowers and Compressors 4. Flow of Compressed Air and Other Gases in Pipes 5. Flow of Air through ducts in ventilation, heating, or air conditioning systems. 18. Fan, Blowers, Compressors

Leu, Tzong-Shyng "Jeremy"

104

Minimax Tests and the Neyman-Pearson Lemma for Capacities  

Microsoft Academic Search

Robust test problems between two approximately known simple hypotheses can be formalized as minimax test problems between two composite hypotheses. We show that if the composite hypotheses can be described in terms of alternating capacities of order 2 (in the sense of Choquet), then the minimax tests are ordinary Neyman-Pearson tests between a fixed representative pair of simple hypotheses; moreover,

Peter J. Huber; Volker Strassen

1973-01-01

105

Nurse Managers’ Work Life Quality and Their Participation in Knowledge Management: A Correlational Study  

PubMed Central

Background: The association between quality of work life and participation in knowledge management is unknown. Objectives: This study aimed to discover the association between quality of work life of nurse managers and their participation in implementing knowledge management. Materials and Methods: This was a correlational study. All nurse managers (71 people) from 11 hospitals affiliated with the Social Security Organization in Tehran, Iran, were included. They were asked to rate their participation in knowledge management and their quality of work life. Data was gathered by a researcher-made questionnaire (May-June 2012). The questionnaire was validated by content and construct validity approaches. Cronbach’s alpha was used to evaluate reliability. Finally, 50 questionnaires were analyzed. The answers were scored and analyzed using mean of scores, T-test, ANOVA (or nonparametric test, if appropriate), Pearson’s correlation coefficient and linear regression. Results: Nurse managers’ performance to implement knowledge management strategies was moderate. A significant correlation was found between quality of work life of nurse managers and their participation in implementing knowledge management strategies (r = 0.82; P < 0.001). The strongest correlations were found between implementation of knowledge management and participation of nurse managers in decision making (r = 0.82; P < 0.001). Conclusions: Improvement of nurse managers’ work life quality, especially in decision-making, may increase their participation in implementing knowledge management.

Hashemi Dehaghi, Zahra; Sheikhtaheri, Abbas; Dehnavi, Fariba

2014-01-01

106

Spatial trends in Pearson Type III statistical parameters  

USGS Publications Warehouse

Spatial trends in the statistical parameters (mean, standard deviation, and skewness coefficient) of a Pearson Type III distribution of the logarithms of annual flood peaks for small rural basins (less than 90 km2) are delineated using a climate factor CT, (T=2-, 25-, and 100-yr recurrence intervals), which quantifies the effects of long-term climatic data (rainfall and pan evaporation) on observed T-yr floods. Maps showing trends in average parameter values demonstrate the geographically varying influence of climate on the magnitude of Pearson Type III statistical parameters. The spatial trends in variability of the parameter values characterize the sensitivity of statistical parameters to the interaction of basin-runoff characteristics (hydrology) and climate. -from Authors

Lichty, R.W.; Karlinger, M.R.

1995-01-01

107

2005 Pearson Education Inc., publishing as Addison-Wesley  

E-print Network

of thousands of big bang photons in every breath you take: the big bang is all around us. It is a theory of the Big Bang #12;#12;© 2005 Pearson Education Inc., publishing as Addison-Wesley #12;Growth of large. · In the scale model, a human life is about 2 tenths of a second! #12;Jan 1st midnight Big Bang #12;Jan 1st

Shirley, Yancy

108

Wayne State University James Pearson Duffy Department of Art and Art History  

E-print Network

Wayne State University James Pearson Duffy Department of Art and Art History Art Department Gallery to his first love from elementary school. #12;Image by Paul Primeau The James Pearson Duffy Department

Cinabro, David

109

Correlation of Masseter Muscle Thickness and Intermolar Width - An Ultrasonography Study  

PubMed Central

Background: To determine the association between the thickness of masseter muscle and the maxillary dental arch width. To explore the influence of gender on masseter muscle thickness. Materials & methods: Seventy subjects (35 females and 35 males) of age 18 to 25 years were selected for the study based on class I molar relationship. The masseter muscle thickness of the right and left sides in every subject were found out through ultrasound scanning of the muscle, in both relaxed and clenched states. The maxillary dental arch width was measured on the study model with an electronic caliper. Student t test, Pearson’s Correlation Coefficient was performed to assess the sample. Results: Masseter Muscle Thickness showed a positive correlation with Maxillary Dental Arch Width r ?0.74. The masseter muscle thickness is greater in male subjects in both relaxed (0.001

Correlation of Masseter Muscle Thickness and Intermolar Width - An Ultrasonography Study. J Int Oral Health 2013; 5(2):28-34. PMID:24155588

Tircoveluri, Saritha; Singh, Johar Rajvinder; Rayapudi, Naveen; Karra, Arjun; Begum, Mohammadi; Challa, Padmalatha

2013-01-01

110

James Pearson Duffy Department of Art and Art History ART DEPARTMENT GALLERY  

E-print Network

and Kirby Street. The James Pearson Duffy Department of Art and Art History is a division of Wayne State1 James Pearson Duffy Department of Art and Art History ART DEPARTMENT GALLERY James Pearson Duffy Department of Art and Art History 150 Art Building Detroit, Michigan 48202 Telephone: (313) 993-7813 Fax

Berdichevsky, Victor

111

James Pearson Duffy Department of Art and Art History ART DEPARTMENT GALLERY  

E-print Network

Pearson Duffy Department of Art and Art History is a division of Wayne State's College of Fine, Performing1 James Pearson Duffy Department of Art and Art History ART DEPARTMENT GALLERY James Pearson Duffy Department of Art and Art History 150 Art Building Detroit, Michigan 48202 Telephone: (313) 577-2423 Fax

Cinabro, David

112

James Pearson Duffy Department of Art and Art History Elaine L. Jacob Gallery  

E-print Network

1 James Pearson Duffy Department of Art and Art History Elaine L. Jacob Gallery 480 W. Hancock (tpyrzewski@wayne.edu) The James Pearson Duffy Department of Art and Art History's Elaine L. Jacob Gallery, Eric Troffkin, Margi Weir, Deborah Alma Wheeler, Barry Whittaker, and Erin Wiersma. The James Pearson

Berdichevsky, Victor

113

On After-Trial Properties of Best Neyman-Pearson Confidence Intervals Teddy Seidenfeld  

E-print Network

On After-Trial Properties of Best Neyman-Pearson Confidence Intervals Teddy Seidenfeld Philosophy #12;ON AFTER-TRIAL PROPERTIES OF BEST NEYMAN- PEARSON CONFIDENCE INTERVALS* TEDDY SEIDENFELD of "best" Neyman-Pearson confidence intervals, we can strengthen a traditional criticism of the orthodox N

Spirtes, Peter

114

Philosophy of Science Association In Defense of the Neyman-Pearson Theory of Confidence Intervals  

E-print Network

Philosophy of Science Association In Defense of the Neyman-Pearson Theory of Confidence Intervals access to Philosophy of Science. http://www.jstor.org #12;IN DEFENSE OF THE NEYMAN-PEARSON THEORY & State University In Philosophical Problems of Statistical Inference, Seidenfeld argues that the Neyman-Pearson

Mayo, Deborah

115

TUFTS UNIVERSITY Department of Psychology and the Eliot-Pearson Department of Child Development  

E-print Network

TUFTS UNIVERSITY Department of Psychology and the Eliot-Pearson Department of Child Development THE DEPARTMENT OF PSYCHOLOGY AND THE ELIOT-PEARSON DEPARTMENT OF CHILD DEVELOPMENT (PENDING APPROVAL OF A CHANGE IN NAME, THE ELIOT-PEARSON DEPARTMENT OF CHILD STUDY AND HUMAN DEVELOPMENT) AT TUFTS UNIVERSITY invite

Patel, Aniruddh D.

116

Copyright 2005 Pearson Education, Inc. publishing as Benjamin Cummings The Nature of Life  

E-print Network

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings The Nature of Life ·Some properties of life #12;Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Life Displays Order #12;Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Life Uses Energy #12

Shirley, Yancy

117

Global-in-time solutions for the isothermal Matovich-Pearson equations  

E-print Network

Global-in-time solutions for the isothermal Matovich-Pearson equations Eduard Feireisl Institute, FRANCE E-mail: Andro.Mikelic@univ-lyon1.fr June 3, 2010 Abstract In this paper we study the Matovich-Pearson on the isothermal case without surface tension. Then the Matovich-Pearson equations represent a nonlinearly coupled

Paris-Sud XI, Université de

118

Northwestern University Archives Evanston, Illinois Charles W. Pearson Family Papers, 1843-1968  

E-print Network

Northwestern University Archives · Evanston, Illinois Charles W. Pearson Family Papers, 1843-1968 Series 11/3/11/2 Boxes 1-15 Introductory Note The Charles Pearson Family Papers document the life and career of Charles W. Pearson, Northwestern alumnus and faculty member (professor and department chair

119

Philosophy of Science Association On After-Trial Criticisms of Neyman-Pearson Theory of Statistics  

E-print Network

Philosophy of Science Association On After-Trial Criticisms of Neyman-Pearson Theory of Statistics://www.jstor.org #12;On After-Trial Criticisms of Neyman-PearsonTheory of Statistics Deborah G. Mayo Virginia predominantly used are from the Neyman-Pearson Theory of statistics (NPT). Nevertheless, NPThas been the target

Mayo, Deborah

120

Presentation for the ANU Educational Research Conference, November 15 -16, 2011 Margot Pearson, Visiting Fellow, CEDAM  

E-print Network

Presentation for the ANU Educational Research Conference, November 15 -16, 2011 Margot Pearson for the ANU Educational Research Conference, November 15 -16, 2011 Margot Pearson, Visiting Fellow, CEDAM database of PhD thesis records, 1948-2008 (Macauley, Evans & Pearson, 2009). This database enables

121

SALD 18A: JMP examples for one-sample t-test  

E-print Network

SALD 18A: JMP examples for one-sample t-test #12;Introduction Notes #12;DO NOT COPY Copyright calculation in JMP To perform a one-sample t-test, select from the data table main menu Analyze 18A-8 To perform a one-sample t-test in JMP, first perform a distribution analysis Under Select

Morgan, Stephen L.

122

Reverend Doctor William Pearson in South Kilworth, Leicestershire  

NASA Astrophysics Data System (ADS)

William Pearson (1767-1847) was a 19th-century astronomer, renowned for his work in positional astronomy and the design of astronomical instruments, both practical and instructional. He was a co-founder in 1820 of the Astronomical Society of London, which later became the Royal Astronomical Society, where his portrait hangs. For 30 years of his astronomical career he was the Rector of South Kilworth, a village in Leicestershire, England, where he erected several observatory buildings, as well as extending the village church and building the village schoolroom. This paper documents his activities in South Kilworth.

Frost, M. A.

2006-12-01

123

Shape modeling with family of Pearson distributions: Langmuir waves  

NASA Astrophysics Data System (ADS)

Two major effects of Langmuir wave electric field influence on spectral line shapes are appearance of depressions shifted from unperturbed line and an additional dynamical line broadening. More realistic and accurate models of Langmuir waves are needed to study these effects with more confidence. In this article we present distribution shapes of a high-quality data set of Langmuir waves electric field observed by the WIND satellite. Using well developed numerical techniques, the distributions of the empirical measurements are modeled by family of Pearson distributions. The results suggest that the existing theoretical models of energy conversion between an electron beam and surrounding plasma is more complex. If the processes of the Langmuir wave generation are better understood, the influence of Langmuir waves on spectral line shapes could be modeled better.

Vidojevic, Sonja

2014-10-01

124

Clopper-Pearson Bounds from HEP Data Cuts  

E-print Network

For the measurement of $N_s$ signals in $N$ events rigorous confidence bounds on the true signal probability $p_{\\rm exact}$ were established in a classical paper by Clopper and Pearson [Biometrica 26, 404 (1934)]. Here, their bounds are generalized to the HEP situation where cuts on the data tag signals with probability $P_s$ and background data with likelihood $P_b

Bernd A. Berg

2000-10-24

125

Neyman-Pearson biometric score fusion as an extension of the sum rule  

NASA Astrophysics Data System (ADS)

We define the biometric performance invariance under strictly monotonic functions on match scores as normalization symmetry. We use this symmetry to clarify the essential difference between the standard score-level fusion approaches of sum rule and Neyman-Pearson. We then express Neyman-Pearson fusion assuming match scores defined using false acceptance rates on a logarithmic scale. We show that by stating Neyman-Pearson in this form, it reduces to sum rule fusion for ROC curves with logarithmic slope. We also introduce a one parameter model of biometric performance and use it to express Neyman-Pearson fusion as a weighted sum rule.

Hube, Jens Peter

2007-04-01

126

Estimating the polyserial correlation coefficient  

Microsoft Academic Search

We develop simple noniterative estimators of the polyserial correlation coefficient. A general relationship between the polyserial correlation and the point polyserial correlation is exploited to give extensions of Pearson's, Brogden's, and Lord's biserial estimators to the multicategory setting. The small sample and asmptotic properties of these estimators are studied in some detail. A comparison with maximum likelihood estimates shows that

Edward J. Bedrick; Frederick C. Breslin

1996-01-01

127

Correlation  

NSDL National Science Digital Library

Three hypothetical rock sections along an East-West transect are provided. Students correlate the three sections using the biostratigraphy of planktic forams (as a proxy for age), benthic forams (as a proxy of depth), and lithology (as a proxy of environment). Students are asked to provide an interpretation of the history of this depositional basin. An ash bed of known age is added and students are asked to determine if this new information affects their interpretation. Finally, an interesting lithologic feature is added, and students are asked to provide a geological explanation.

Pennilyn Higgins

128

When "t"-Tests or Wilcoxon-Mann-Whitney Tests Won't Do  

ERIC Educational Resources Information Center

"t"-Tests are widely used by researchers to compare the average values of a numeric outcome between two groups. If there are doubts about the suitability of the data for the requirements of a "t"-test, most notably the distribution being non-normal, the Wilcoxon-Mann-Whitney test may be used instead. However, although often applied, both tests may…

McElduff, Fiona; Cortina-Borja, Mario; Chan, Shun-Kai; Wade, Angie

2010-01-01

129

Using the Student's "t"-Test with Extremely Small Sample Sizes  

ERIC Educational Resources Information Center

Researchers occasionally have to work with an extremely small sample size, defined herein as "N" less than or equal to 5. Some methodologists have cautioned against using the "t"-test when the sample size is extremely small, whereas others have suggested that using the "t"-test is feasible in such a case. The present…

de Winter, J. C .F.

2013-01-01

130

Complementarity and correlations  

E-print Network

We investigate the relation between complementary properties and correlations of composite quantum systems. We introduce three measures of correlations which are based on local measurements in complementary bases. These measures are linked to the mutual information, the Pearson correlation coefficient and the sum of conditional probabilities, respectively. We show that states which have complementary correlations beyond a certain threshold must be entangled. The reverse is not true, however. We also show that, surprisingly, states with non-zero quantum correlations may have less correlations on complementary observables than classically correlated states.

Lorenzo Maccone; Dagmar Bruss; Chiara Macchiavello

2014-08-28

131

James Pearson Duffy Department of Art and Art History ART DEPARTMENT GALLERY  

E-print Network

Exhibition DETROIT (Dec. 23, 2011) ­ Wayne State University's Art Department Gallery presents 2012 MFA Thesis to the public. The Art Department Gallery is located in the Community Arts Building on the campus of Wayne StateJames Pearson Duffy Department of Art and Art History ART DEPARTMENT GALLERY James Pearson Duffy

Berdichevsky, Victor

132

James Pearson Duffy Department of Art and Art History ART DEPARTMENT GALLERY  

E-print Network

Exhibition The Art Department Gallery, Wayne State University, Detroit, MI is pleased to present Tri Department of Art and Art History is a division of Wayne State's College of Fine, Performing1 James Pearson Duffy Department of Art and Art History ART DEPARTMENT GALLERY James Pearson Duffy

Berdichevsky, Victor

133

ART DEPARTMENT GALLERY James Pearson Duffy Department of Art and Art History  

E-print Network

1 ART DEPARTMENT GALLERY James Pearson Duffy Department of Art and Art History 5400 Reuther Mall, 150 Art Building Detroit, Michigan 48202 Telephone: (313) 577-0770 Fax: (313) 577-8935 FOR IMMEDIATE. Pyrzewski (tpyrzewski@wayne.edu) The James Pearson Duffy Department of Art and Art History's Art Department

Cinabro, David

134

TUFTS UNIVERSITY Eliot-Pearson Department of Child Study and Human Development  

E-print Network

TUFTS UNIVERSITY Eliot-Pearson Department of Child Study and Human Development ASSISTANT PROFESSOR POSITION IN DEVELOPMENTAL METHODOLOGY THE ELIOT-PEARSON DEPARTMENT OF CHILD STUDY AND HUMAN DEVELOPMENT or in one of the fields associated with developmental science (e.g., human development, child development

Dennett, Daniel

135

Contingency Plans for Air Traffic Management Karl Sundequist Blomdahl, Pierre Flener, and Justin Pearson  

E-print Network

Pearson Department of Information Technology Uppsala University, Box 337, SE ­ 751 05 Uppsala, Sweden KarlContingency Plans for Air Traffic Management Karl Sundequist Blomdahl, Pierre Flener, and Justin.Sundequist Blomdahl.1559@student.uu.se, Pierre.Flener@it.uu.se, Justin.Pearson@it.uu.se Abstract We present two

Flener, Pierre

136

A new correlation coefficient for bivariate time-series data  

NASA Astrophysics Data System (ADS)

The correlation in time series has received considerable attention in the literature. Its use has attained an important role in the social sciences and finance. For example, pair trading in finance is concerned with the correlation between stock prices, returns, etc. In general, Pearson’s correlation coefficient is employed in these areas although it has many underlying assumptions which restrict its use. Here, we introduce a new correlation coefficient which takes into account the lag difference of data points. We investigate the properties of this new correlation coefficient. We demonstrate that it is more appropriate for showing the direction of the covariation of the two variables over time. We also compare the performance of the new correlation coefficient with Pearson’s correlation coefficient and Detrended Cross-Correlation Analysis (DCCA) via simulated examples.

Erdem, Orhan; Ceyhan, Elvan; Varli, Yusuf

2014-11-01

137

Mitochondrial DNA deletion in a patient with combined features of Leigh and Pearson syndromes  

SciTech Connect

We describe a heteroplasmic 4237 bp mitochondrial DNA (mtDNA) deletion in an 11 year old girl who has suffered from progressive illness since birth. She has some features of Leigh syndrome (global developmental delay with regression, brainstem dysfunction and lactic acidosis), together with other features suggestive of Pearson syndrome (history of pancytopenia and failure to thrive). The deletion was present at a level greater than 50% in skeletal muscle, but barely detectable in skin fibroblasts following Southern blot analysis, and only observed in blood following PCR analysis. The deletion spanned nt 9498 to nt 13734, and was flanked by a 12 bp direct repeat. Genes for cytochrome c oxidase subunit III, NADH dehydrogenase subunits 3, 4L, 4 and 5, and tRNAs for glycine, arginine, histidine, serine({sup AGY}) and leucine({sup CUN}) were deleted. Southern blotting also revealed an altered Apa I restriction site which was shown by sequence analysis to be caused by G{r_arrow}A nucleotide substitution at nt 1462 in the 12S rRNA gene. This was presumed to be a polymorphism. No abnormalities of mitochondrial ultrastructure, distribution or of respiratory chain enzyme complexes I-IV in skeletal muscle were observed. Mitochondrial disorders with clinical features overlapping more than one syndrome have been reported previously. This case further demonstrates the difficulty in correlating observed clinical features with a specific mitochondrial DNA mutation.

Blok, R.B.; Thorburn, D.R.; Danks, D.M. [Royal Children`s Hospital, Melbourne (Australia)] [and others

1994-09-01

138

A 13-Moment Two-Fluid Plasma Physics Model Based on a Pearson Type-IV Distribution Function  

E-print Network

A 13-Moment Two-Fluid Plasma Physics Model Based on a Pearson Type-IV Distribution Function Shaun;#12;University of Washington Abstract A 13-Moment Two-Fluid Plasma Physics Model Based on a Pearson Type-moment model is derived in three dimensions for a Pearson-IV distribution function and the eigensystem

Shumlak, Uri

139

Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0-13-148521-0 The Instruction Set  

E-print Network

Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0

Boyer, Michel

140

Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0-13-148521-0 The Instruction Set  

E-print Network

1 Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0 Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0

Boyer, Michel

141

Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0-13-148521-0 La couche micro-architecture (Chapter 4)  

E-print Network

Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0

Boyer, Michel

142

Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0-13-148521-0 La couche micro-architecture (Chapter 4)  

E-print Network

Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0;Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights

Boyer, Michel

143

Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0-13-148521-0 The Operating System  

E-print Network

Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0 Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0

Boyer, Michel

144

Measuring correlations between non-stationary series with DCCA coefficient  

NASA Astrophysics Data System (ADS)

In this short report, we investigate the ability of the DCCA coefficient to measure correlation level between non-stationary series. Based on a wide Monte Carlo simulation study, we show that the DCCA coefficient can estimate the correlation coefficient accurately regardless the strength of non-stationarity (measured by the fractional differencing parameter d). For a comparison, we also report the results for the standard Pearson correlation coefficient. The DCCA coefficient dominates the Pearson coefficient for non-stationary series.

Kristoufek, Ladislav

2014-05-01

145

The Evolution of Pearsons Correlation Coefficient/Exploring Relationships between Two Quantitative Variables  

NSDL National Science Digital Library

The evolution of ideas is often ignored in the teaching of statistics. It is important to show students how definitions and formulas evolve. This activity describes a fairly straightforward activity of how measures of association can evolve.

Gary Kader

146

Pearson’s correlations between moisture content, drip loss, expressible fluid and salt-induced water gain of broiler pectoralis major muscle  

Technology Transfer Automated Retrieval System (TEKTRAN)

Moisture content, drip loss, expressible fluid, and % salt-induced water gain are widely used to estimate water states and water-holding capacity of raw meat. However, the relationships between these four measurements of broiler pectoralis (p.) major muscle describe are not well described. The objec...

147

Using a Nonparametric Bootstrap to Obtain a Confidence Interval for Pearson’s r with Cluster Randomized Data: A Case Study  

PubMed Central

A nonparametric bootstrap was used to obtain an interval estimate of Pearson’s r, and test the null hypothesis that there was no association between 5th grade students’ positive substance use expectancies and their intentions to not use substances. The students were participating in a substance use prevention program in which the unit of randomization was a public middle school. The bootstrap estimate indicated that expectancies explained 21% of the variability in students’ intentions (r = 0.46, 95% CI = [0.40, 0.50]). This case study illustrates the use of a nonparametric bootstrap with cluster randomized data and the danger posed if outliers are not identified and addressed. Editors’ Strategic Implications: Prevention researchers will benefit from the authors’ detailed description of this nonparametric bootstrap approach for cluster randomized data and their thoughtful discussion of the potential impact of cluster sizes and outliers. PMID:19685290

Elek, Elvira; Kulis, Stephen; Marsiglia, Flavio

2009-01-01

148

Robust parametric bootstrap test with MOM estimator: An alternative to independent sample t-test  

NASA Astrophysics Data System (ADS)

Normality and homogeneity are two major assumptions that need to be fulfilled when using independent sample t-test. However, not all data encompassed with these assumptions. Consequently, the result produced by independent sample t-test becomes invalid. Therefore, the alternative is to use robust statistical procedure in handling the problems of nonnormality and variances heterogeneity. This study proposed to use Parametric Bootstrap test with popular robust estimators, MADn and Tn which empirically determines the amount of trimming. The Type I error rates produced by each procedure were examined and compared with classical parametric test and nonparametric test namely independent sample t-test and Mann Whitney test, respectively. 5000 simulated data sets are used in this study in order to generate the Type I error for each procedure. The findings of this study indicate that the Parametric Bootstrap test with MADn and Tn produces the best Type I error control compared to the independent sample t-test and the Mann Whitney test under nonnormal distribution, heterogeneous variances and unbalanced design. Then, the performance of each procedure was demonstrated using real data.

Harun, Nurul Hanis; Yusof, Zahayu Md

2014-12-01

149

Comparing Groups in a Before-After Design: When t Test and ANCOVA Produce Different Results  

ERIC Educational Resources Information Center

Background: Researchers often test people before and after some treatment and compare these scores with a control group. Sometimes it is not possible to allocate people into conditions randomly, which means the initial scores for the two groups may differ. There are two main approaches: t test on the gain scores and ANCOVA partialling out the…

Wright, Daniel B.

2006-01-01

150

Comparison of the Mahalanobis distance and Pearson's ?² statistic as measures of similarity of isotope patterns.  

PubMed

To extract a genuine peptide signal from a mass spectrum, an observed series of peaks at a particular mass can be compared with the isotope distribution expected for a peptide of that mass. To decide whether the observed series of peaks is similar to the isotope distribution, a similarity measure is needed. In this short communication, we investigate whether the Mahalanobis distance could be an alternative measure for the commonly employed Pearson's ?(2) statistic. We evaluate the performance of the two measures by using a controlled MALDI-TOF experiment. The results indicate that Pearson's ?(2) statistic has better discriminatory performance than the Mahalanobis distance and is a more robust measure. PMID:24249044

Zamanzad Ghavidel, Fatemeh; Claesen, Jürgen; Burzykowski, Tomasz; Valkenborg, Dirk

2014-02-01

151

Comparison of the Mahalanobis Distance and Pearson's ?2 Statistic as Measures of Similarity of Isotope Patterns  

NASA Astrophysics Data System (ADS)

To extract a genuine peptide signal from a mass spectrum, an observed series of peaks at a particular mass can be compared with the isotope distribution expected for a peptide of that mass. To decide whether the observed series of peaks is similar to the isotope distribution, a similarity measure is needed. In this short communication, we investigate whether the Mahalanobis distance could be an alternative measure for the commonly employed Pearson's ?2 statistic. We evaluate the performance of the two measures by using a controlled MALDI-TOF experiment. The results indicate that Pearson's ?2 statistic has better discriminatory performance than the Mahalanobis distance and is a more robust measure.

Zamanzad Ghavidel, Fatemeh; Claesen, Jürgen; Burzykowski, Tomasz; Valkenborg, Dirk

2013-11-01

152

Contextualisation in the revised dual representation theory of PTSD: a response to Pearson and colleagues.  

PubMed

Three recent studies (Pearson, 2012; Pearson, Ross, & Webster, 2012) purported to test the revised dual representation theory of posttraumatic stress disorder (Brewin, Gregory, Lipton, & Burgess, 2010) by manipulating the amount of additional information accompanying traumatic stimulus materials and assessing the effect on subsequent intrusive memories. Here we point out that these studies involve a misunderstanding of the meaning of "contextual" within the theory, such that the manipulation would be unlikely to have had the intended effect and the results are ambiguous with respect to the theory. Past and future experimental tests of the theory are discussed. PMID:24041427

Brewin, Chris R; Burgess, Neil

2014-03-01

153

IMAGE BASED RENDERING WITH DEPTH CAMERAS: HOW MANY ARE NEEDED? Christopher Gilliam, James Pearson, Mike Brookes and Pier Luigi Dragotti  

E-print Network

IMAGE BASED RENDERING WITH DEPTH CAMERAS: HOW MANY ARE NEEDED? Christopher Gilliam, James Pearson, Mike Brookes and Pier Luigi Dragotti Electrical and Electronic Engineering Department, Imperial College

Dragotti, Pier Luigi

154

Magnetic resonance imaging (MRI)-guided transurethral ultrasound therapy of the prostate: a preclinical study with radiological and pathological correlation using customised MRI-based moulds  

PubMed Central

Objective To characterise the feasibility and safety of a novel transurethral ultrasound (US)-therapy device combined with real-time multi-plane magnetic resonance imaging (MRI)-based temperature monitoring and temperature feedback control, to enable spatiotemporally precise regional ablation of simulated prostate gland lesions in a preclinical canine model. To correlate ablation volumes measured with intra-procedural cumulative thermal damage estimates, post-procedural MRI, and histopathology. Materials and methods Three dogs were treated with three targeted ablations each, using a prototype MRI-guided transurethral US-therapy system (Philips Healthcare, Vantaa, Finland). MRI provided images for treatment planning, guidance, real-time multi-planar thermometry, as well as post-treatment evaluation of efficacy. After treatment, specimens underwent histopathological analysis to determine the extent of necrosis and cell viability. Statistical analyses (Pearson’s correlation, Student’s t-test) were used to evaluate the correlation between ablation volumes measured with intra-procedural cumulative thermal damage estimates, post-procedural MRI, and histopathology. Results MRI combined with a transurethral US-therapy device enabled multi-planar temperature monitoring at the target as well as in surrounding tissues, allowing for safe, targeted, and controlled ablations of prescribed lesions. Ablated volumes measured by cumulative thermal dose positively correlated with volumes determined by histopathological analysis (r2 0.83, P < 0.001). Post-procedural contrast-enhanced and diffusion-weighted MRI showed a positive correlation with non-viable areas on histopathological analysis (r2 0.89, P < 0.001, and r20.91, P = 0.003, respectively). Additionally, there was a positive correlation between ablated volumes according to cumulative thermal dose and volumes identified on post-procedural contrast-enhanced MRI (r2 0.77, P < 0.01). There was no difference in mean ablation volumes assessed with the various analysis methods (P > 0.05, Student’s t-test). Conclusions MRI-guided transurethral US therapy enabled safe and targeted ablations of prescribed lesions in a preclinical canine prostate model. Ablation volumes were reliably predicted by intra- and post-procedural imaging. Clinical studies are needed to confirm the feasibility, safety, oncological control, and functional outcomes of this therapy in patients in whom focal therapy is indicated. PMID:23746198

Partanen, Ari; Yerram, Nitin K.; Trivedi, Hari; Dreher, Matthew R.; Oila, Juha; Hoang, Anthony N.; Volkin, Dmitry; Nix, Jeffrey; Turkbey, Baris; Bernardo, Marcelino; Haines, Diana C.; Benjamin, Compton J.; Linehan, W. Marston; Choyke, Peter; Wood, Bradford J.; Ehnholm, Gösta J.; Venkatesan, Aradhana M.; Pinto, Peter A.

2013-01-01

155

A Comparison of Six Robust Correlation Estimators.  

ERIC Educational Resources Information Center

A Monte Carlo investigation of six robust correlation estimators was conducted for data from distributions with longer than Gaussian tails: a bisquare coefficient, the Tukey correlation, the standardized sums and differences, a biweight standardized sums and differences, the transformed Spearman's rho and a bivariate trimmed Pearson. Evaluation of…

Baranowski, B. Bonnie; Halperin, Silas

156

updated on 8/6/2012 by L. Hall-Pearson I. INTRODUCTION  

E-print Network

updated on 8/6/2012 by L. Hall-Pearson I. INTRODUCTION The Albert Einstein College of Medicine of Yeshiva University ("Einstein"), one of the nation's premier institutions for medical education, basic of Interest. In addition to medical education, a central academic activity of Einstein is discovery

Kenny, Paraic

157

James Pearson Duffy Department of Art and Art History Elaine L. Jacob Gallery  

E-print Network

1 James Pearson Duffy Department of Art and Art History Elaine L. Jacob Gallery 480 W. Hancock of Art and Art History's Elaine L. Jacob Gallery is pleased to present SILENT WATCH: CONTEMPORARY PRINTS as several artists' books and a three-dimensional piece. The exhibition includes prints by the widely

Berdichevsky, Victor

158

James Pearson Duffy Department of Art and Art History Elaine L. Jacob Gallery  

E-print Network

1 James Pearson Duffy Department of Art and Art History Elaine L. Jacob Gallery 480 W. Hancock of Art and Art History's Elaine L. Jacob Gallery is pleased to present Oh Canada!...beyond trees and uses tools and equipment associated with historic modes of transportation, including canoes, dogsleds

Berdichevsky, Victor

159

A Psychometric Measurement Model for Adult English Language Learners: Pearson Test of English Academic  

ERIC Educational Resources Information Center

The aim of this study was to apply Rasch modeling to an examination of the psychometric properties of the "Pearson Test of English Academic" (PTE Academic). Analyzed were 140 test-takers' scores derived from the PTE Academic database. The mean age of the participants was 26.45 (SD = 5.82), ranging from 17 to 46. Conformity of the participants'…

Pae, Hye K.

2012-01-01

160

Karl Pearson's mathematization of inheritance: from ancestral heredity to Mendelian genetics (1895-1909).  

PubMed

Long-standing claims have been made for nearly the entire twentieth century that the biometrician, Karl Pearson, and colleague, W. F. R. Weldon, rejected Mendelism as a theory of inheritance. It is shown that at the end of the nineteenth century Pearson considered various theories of inheritance (including Francis Galton's law of ancestral heredity for characters underpinned by continuous variation), and by 1904 he 'accepted the fundamental idea of Mendel' as a theory of inheritance for discontinuous variation. Moreover, in 1909, he suggested a synthesis of biometry and Mendelism. Despite the many attempts made by a number of geneticists (including R. A. Fisher in 1936) to use Pearson's chi-square (X2, P) goodness-of-fit test on Mendel's data, which produced results that were 'too good to be true', Weldon reached the same conclusion in 1902, but his results were never acknowledged. The geneticist and arch-rival of the biometricians, Williams Bateson, was instead exceptionally critical of this work and interpreted this as Weldon's rejection of Mendelism. Whilst scholarship on Mendel, by historians of science in the last 18 years, has led to a balanced perspective of Mendel, it is suggested that a better balanced and more rounded view of the hereditarian-statistical work of Pearson, Weldon, and the biometricians is long overdue. PMID:11619806

Magnello, M E

1998-01-01

161

The Beta Distribution,moment method, Karl Pearson and R.A.Fisher  

SciTech Connect

Simulation studies provide four moment approximating distributions to each of the four parameters of a beta distribution (Pearson Type I). Two of the parameters refer to origin and scale, two to shape (skewness and kurtosis). Type I random number generator is checked out, and the stability of moments of random samples of size n over cycles; particular attention is paid to shape parameter moments. In Type I region of validity (referred to skewness and kurtosis), moment methods become unstable in the neighborhood of Type III ({chi}{sup 2}) line, and ultimately abort. Thus extremely large variances and large higher moments arise. We probe the cause of this phenomenon. Simulation studies are turned to since alternative power series methods are forbiddingly complicated. However, use is made of the delta method to provide asymptotic variances of the estimators, and asymptotic variances of percentage points of the basic distribution. An account of work on the subject by K. Pearson, some of it a century ago, is given. In particular an important paper by Pearson and Filon provides some estimates of probable errors of moment parameter estimators such as the basic distribution parameters, the mode, the skewness and others. The heated controversy between Pearson and Fisher is considered.

Bowman, Kimiko o [ORNL

2007-01-01

162

"Describing our whole experience": the statistical philosophies of W. F. R. Weldon and Karl Pearson.  

PubMed

There are two motivations commonly ascribed to historical actors for taking up statistics: to reduce complicated data to a mean value (e.g., Quetelet), and to take account of diversity (e.g., Galton). Different motivations will, it is assumed, lead to different methodological decisions in the practice of the statistical sciences. Karl Pearson and W. F. R. Weldon are generally seen as following directly in Galton's footsteps. I argue for two related theses in light of this standard interpretation, based on a reading of several sources in which Weldon, independently of Pearson, reflects on his own motivations. First, while Pearson does approach statistics from this "Galtonian" perspective, he is, consistent with his positivist philosophy of science, utilizing statistics to simplify the highly variable data of biology. Weldon, on the other hand, is brought to statistics by a rich empiricism and a desire to preserve the diversity of biological data. Secondly, we have here a counterexample to the claim that divergence in motivation will lead to a corresponding separation in methodology. Pearson and Weldon, despite embracing biometry for different reasons, settled on precisely the same set of statistical tools for the investigation of evolution. PMID:22035721

Pence, Charles H

2011-12-01

163

Tactile SLAM with a biomimetic whiskered robot Charles Fox, Mat Evans, Martin Pearson and Tony Prescott  

E-print Network

Tactile SLAM with a biomimetic whiskered robot Charles Fox, Mat Evans, Martin Pearson and Tony in grid based simultaneous localisation and mapping (SLAM) with biomimetic whisker sensors, and show how, or adversarial environments where covert (emission-less) sensing is re- quired. Biomimetic touch sensors

Barker, Jon

164

Batch and online learning algorithms for Nonconvex Neyman-Pearson classification  

E-print Network

on DC programming and stochastic gradient method well suited for large scale datasets. Empirical and Phrases: Neyman-Pearson, Nonconvex SVM, DC algorithm, online learning 1. INTRODUCTION Consider a binary Iy f(x)0 that is neither continuous nor convex. Replacing this 0­ 1 loss with the SVM Hinge loss has

Bottou, Léon

165

Batch and online learning algorithms for Nonconvex Neyman-Pearson classification  

E-print Network

on DC programming and stochastic gradient method well suited for large scale datasets. Empirical and Phrases: Neyman-Pearson, Nonconvex SVM, DC algorithm, online learning 1. INTRODUCTION Consider a binary(x)0 that is neither continuous nor convex. Replacing this 0­ 1 loss with the SVM Hinge loss has been

Paris-Sud XI, Université de

166

Batch and online learning algorithms for Nonconvex NeymanPearson classification  

E-print Network

algorithm based on DC programming and stochastic gradient method well suited for large scale datasets Key Words and Phrases: Neyman­Pearson, Nonconvex SVM, DC algorithm, online learning 1. INTRODUCTION I y f(x)#0 that is neither continuous nor convex. Replacing this 0-- 1 loss with the SVM Hinge loss

Bottou, Léon

167

Children with autism do not overimitate L. Marsh, A. Pearson, D. Ropar & A. Hamilton  

E-print Network

Children with autism do not overimitate L. Marsh, A. Pearson, D. Ropar & A. Hamilton School object, typically developing (TD) children faithfully copy both necessary and visibly unnecessary actions to be causally transparent in their mechanism, young children's causal reasoning about novel objects is unclear

Hamilton, Antonia

168

A New Way to Teach (or Compute) Pearson's "r" without Reliance on Cross-Products  

ERIC Educational Resources Information Center

Many students have difficulty seeing the conceptual link between bivariate data displayed in a scatterplot and the statistical summary of the relationship, "r." This article shows how to teach (and compute) "r" such that each datum's direct and indirect influences are made apparent and used in a new formula for calculating Pearson's "r."

Huck, Schuyler W.; Ren, Bixiang; Yang, Hongwei

2007-01-01

169

Comparison of Maximum Likelihood and Pearson Chi-Square Statistics for Assessing Latent Class Models.  

ERIC Educational Resources Information Center

When latent class parameters are estimated, maximum likelihood and Pearson chi-square statistics can be derived for assessing the fit of the model to the data. This study used simulated data to compare these two statistics, and is based on mixtures of latent binomial distributions, using data generated from five dichotomous manifest variables.…

Holt, Judith A.; Macready, George B.

170

Representation of two-dimensional ion implantation rest distributions by Pearson distribution curves for silicon technology  

NASA Astrophysics Data System (ADS)

This is the second of two papers concerned with fitting Pearson curves to Monte Carlo simulations of implants into amorphous targets. In the first paper [ Solid-St. Electron.35, 1151 (1992)] it was shown that accurate Pearson curve fitting to projected range profiles is possible when implant profiles are available for which optimised moments can be generated. In the present paper we extend the fitting to simulations of two-dimensional rest distributions. Comparisons are made between Pearson curve fits and the original high-resolution implant profiles, in two-dimensions, for the ions B and As implanted into amorphous silicon. The profiles were derived from Monte Carlo simulations, each of one million ion trajectories. Fit coefficients are provided that allow the regeneration of the moment surfaces for the depth and implantation energy dependent lateral straggle and lateral kurtosis for the ions B, P, As and Sb implanted, with energies in the range 25-300 keV, into targets of amorphous silicon, silicon dioxide and silicon nitride. The depth-dependent lateral distribution is then constructed using symmetrical Pearson curves driven by analytical formulae for the moment surfaces. The two-dimensional rest distribution is then reconstructed from the product of this depth-dependent lateral distribution and the projected range distribution derived in the first paper.

Bowyer, M. D. J.; Ashworth, D. G.; Oven, R.

1996-01-01

171

Risk stratification with a point-of-care cardiac troponin T test in acute myocardial infarction  

Microsoft Academic Search

Troponin T has been used successfully to risk stratify patients with acute coronary syndromes, but the utility of this approach using a rapid bedside assay in patients undergoing thrombolysis for ST-segment elevation acute myocardial infarction has not been assessed in a large population. We assessed whether a point-of-care, qualitative troponin T test at enrollment could independently risk-stratify patients randomized to

E. Magnus Ohman; Paul W Armstrong; Harvey D White; Christopher B Granger; Robert G Wilcox; W. Douglas Weaver; W. Brian Gibler; Amanda L Stebbins; Cresha Cianciolo; Robert M Califf; Eric J Topol

1999-01-01

172

When t-tests or Wilcoxon-Mann-Whitney tests won't do  

NSDL National Science Digital Library

t-Tests are widely used by researchers to compare the average values of a numeric outcome between two groups. If there are doubts about the suitability of the data for the requirements of a t-test, most notably the distribution being non-normal, the Wilcoxon-Mann-Whitney test may be used instead. However, although often applied, both tests may be invalid when discrete and/or extremely skew data are analyzed. In medicine, extremely skewed data having an excess of zeroes are often observed, representing a numeric outcome that does not occur for a large percentage of cases (so is often zero) but which also sometimes takes relatively large values. For data such as this, application of the t-test or Wilcoxon-Mann-Whitney test could lead researchers to draw incorrect conclusions. A valid alternative is regression modeling to quantify the characteristics of the data. The increased availability of software has simplified the application of these more complex statistical analyses and hence facilitates researchers to use them. In this article, we illustrate the methodology applied to a comparison of cyst counts taken from control and steroid-treated fetal mouse kidneys.

Fiona McElduff (University College London)

2010-09-01

173

Improving standards in brain-behavior correlation analyses  

PubMed Central

Associations between two variables, for instance between brain and behavioral measurements, are often studied using correlations, and in particular Pearson correlation. However, Pearson correlation is not robust: outliers can introduce false correlations or mask existing ones. These problems are exacerbated in brain imaging by a widespread lack of control for multiple comparisons, and several issues with data interpretations. We illustrate these important problems associated with brain-behavior correlations, drawing examples from published articles. We make several propositions to alleviate these problems. PMID:22563313

Rousselet, Guillaume A.; Pernet, Cyril R.

2012-01-01

174

Confidence interval and the Student's t-test Are you a blogger? Interested in participating in a paid blogging study?  

E-print Network

Confidence interval and the Student's t-test Are you a blogger? Interested in participating-test to use ! t-test for one variable: calculating confidence interval for mean ! Three types of t to confidence interval for a moment: If we want to find out the mean of a population, but ! the population

Masci, Frank

175

Wanted: guidelines for reporting correlations  

NSDL National Science Digital Library

Recently (1Â?3), there have been guidelines published for authors regarding what and how statistics should be reported when describing the differences between groups of observations. There seems to be a paucity of such guidance with respect to describing the correlation between groups of observations. Of particular concern to me is the way in which Pearson product-moment correlations are reported in many journals.

Bartholomew Kay (University of Auckland Sport and Exercise Science)

2009-06-01

176

Excursions in Modern Mathematics, 7e: 3.1 -1Copyright 2010 Pearson Education, Inc. 3 The Mathematics of Sharing  

E-print Network

-Division Game #12;Excursions in Modern Mathematics, 7e: 3.1 - 4Copyright © 2010 Pearson Education, Inc Education, Inc. A fair-division method is a set of rules that define how the game is to be played. ThusExcursions in Modern Mathematics, 7e: 3.1 - 1Copyright © 2010 Pearson Education, Inc. 3

Lee, Carl

177

Calculating and reporting effect sizes to facilitate cumulative science: a practical primer for t-tests and ANOVAs.  

PubMed

Effect sizes are the most important outcome of empirical studies. Most articles on effect sizes highlight their importance to communicate the practical significance of results. For scientists themselves, effect sizes are most useful because they facilitate cumulative science. Effect sizes can be used to determine the sample size for follow-up studies, or examining effects across studies. This article aims to provide a practical primer on how to calculate and report effect sizes for t-tests and ANOVA's such that effect sizes can be used in a-priori power analyses and meta-analyses. Whereas many articles about effect sizes focus on between-subjects designs and address within-subjects designs only briefly, I provide a detailed overview of the similarities and differences between within- and between-subjects designs. I suggest that some research questions in experimental psychology examine inherently intra-individual effects, which makes effect sizes that incorporate the correlation between measures the best summary of the results. Finally, a supplementary spreadsheet is provided to make it as easy as possible for researchers to incorporate effect size calculations into their workflow. PMID:24324449

Lakens, Daniël

2013-01-01

178

Pearson's marrow-pancreas syndrome. A multisystem mitochondrial disorder in infancy.  

PubMed Central

Pearson's marrow-pancreas syndrome (McKusick No. 26056) is a fatal disorder of hitherto unknown etiology involving the hematopoietic system, exocrine pancreas, liver, and kidneys. The observation of high lactate/pyruvate molar ratios in plasma and abnormal oxidative phosphorylation in lymphocytes led us to postulate that Pearson's syndrome belongs to the group of mitochondrial cytopathies. Since rearrangements of the mitochondrial genome between direct DNA repeats were consistently found in all tissues tested, our results show that this disease is in fact a multisystem mitochondrial disorder, as suggested by the clinical course of the patients. Based on these observations, we would suggest giving consideration to the hypothesis of a defect of oxidative phosphorylation in elucidating the origin of other syndromes, especially those associated with an abnormal oxidoreduction status in plasma. Images PMID:2243133

Rötig, A; Cormier, V; Blanche, S; Bonnefont, J P; Ledeist, F; Romero, N; Schmitz, J; Rustin, P; Fischer, A; Saudubray, J M

1990-01-01

179

Canonical Correlation and Chi-Square: Relationships and Interpretation  

Microsoft Academic Search

A 2 × 2 chi-square can be computed from a phi coefficient, which is the Pearson correlation between two binomial variables. Similarly, chi-square for larger contingency tables can be computed from canonical correlation coefficients. The authors address the following series of issues involving this relationship: (a) how to represent a contingency table in terms of a correlation matrix involving r

William P. Dunlap; Charles J. Brody; Tammy Greer

2000-01-01

180

Choosing the Best Correction Formula for the Pearson r[superscript 2] Effect Size  

ERIC Educational Resources Information Center

In the present Monte Carlo simulation study, the authors compared bias and precision of 7 sampling error corrections to the Pearson r[superscript 2] under 6 x 3 x 6 conditions (i.e., population ? values of 0.0, 0.1, 0.3, 0.5, 0.7, and 0.9, respectively; population shapes normal, skewness = kurtosis = 1, and skewness = -1.5 with kurtosis = 3.5;…

Skidmore, Susan Troncoso; Thompson, Bruce

2011-01-01

181

Distribution of eigenvalues of detrended cross-correlation matrix  

NASA Astrophysics Data System (ADS)

This letter is devoted to the cross-correlation analysis of non-stationary multivariate data, in which the detrended cross-correlation matrix based on the detrended cross-correlation coefficient is studied. The relationship between Pearson's cross-correlation coefficient and the detrended cross-correlation coefficient is analyzed. As a special case of random matrix theory, the distribution of the eigenvalues of the detrended cross-correlation matrix for purely random variables is derived.

Zhao, Xiaojun; Shang, Pengjian; Lin, Aijing

2014-08-01

182

The Pearson-Readhead Survey of Compact Extragalactic Radio Sources From Space. II. Analysis of Source Properties  

E-print Network

We have performed a multi-dimensional correlation analysis on the observed properties of a statistically complete core-selected sample of compact radio-loud active galactic nuclei, based on data from the VLBI Space Observing Programme (Paper I) and previously published studies. Our sample is drawn from the well-studied Pearson-Readhead (PR) survey, and is ideally suited for investigating the general effects of relativistic beaming in compact radio sources. In addition to confirming many previously known correlations, we have discovered several new trends that lend additional support to the beaming model. These trends suggest that the most highly beamed sources in core-selected samples tend to have a) high optical polarizations; b) large pc/kpc-scale jet misalignments; c) prominent VLBI core components; d) one-sided, core, or halo radio morphology on kiloparsec scales; e) narrow emission line equivalent widths; and f) a strong tendency for intraday variability at radio wavelengths. We have used higher resolution space and ground-based VLBI maps to confirm the bi-modality of the jet misalignment distribution for the PR survey, and find that the sources with aligned parsec- and kiloparsec-scale jets generally have arcsecond-scale radio emission on both sides of the core. The aligned sources also have broader emission line widths. We find evidence that the BL Lacertae objects in the PR survey are all highly beamed, and have very similar properties to the high-optically polarized quasars, with the exception of smaller redshifts. A cluster analysis on our data shows that after partialing out the effects of redshift, the luminosities of our sample objects in various wave bands are generally well-correlated with each other, but not with other source properties.

M. L. Lister; S. J. Tingay; R. A. Preston

2001-02-15

183

Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0-13-148521-0 La couche micro-architecture (Chapter 4)  

E-print Network

1 Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0

Boyer, Michel

184

The James Pearson Duffy Department of Art and Art History Newsletter is a publication of the Wayne State University Department of Art and  

E-print Network

FALL NEWSLETTER #12;The James Pearson Duffy Department of Art and Art History Newsletter not be reproduced without permission. This newsletter is designed and edited by the James Pearson Duffy Department;Message from the Chair John J. Richardson, Chair James Pearson Duffy Department of Art and Art History 2

Cinabro, David

185

Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0-13-148521-0 The Digital Logic Level  

E-print Network

Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0-13-148521-0 Gates Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0

Boyer, Michel

186

Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0-13-148521-0 The Digital Logic Level  

E-print Network

1 Tanenbaum, Structured Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0-13-148521-0 Gates Computer Organization, Fifth Edition, (c) 2006 Pearson Education, Inc. All rights reserved. 0

Boyer, Michel

187

The Pearson walk with shrinking steps in two dimensions This article has been downloaded from IOPscience. Please scroll down to see the full text article.  

E-print Network

The Pearson walk with shrinking steps in two dimensions This article has been downloaded from The Pearson walk with shrinking steps in two dimensions C A Serino and S Redner Center for Polymer Studies.iop.org/JSTAT/2010/P01006 doi:10.1088/1742-5468/2010/01/P01006 Abstract. We study the shrinking Pearson random walk

Redner, Sidney

188

Pearson dismisses talk of STFC crisis : Research Fortnight : Feb 21 There is no crisis in physics funding and the Science and Technology Facilities Council's 80  

E-print Network

Pearson dismisses talk of STFC crisis : Research Fortnight : Feb 21 There is no crisis in physics funding and the Science and Technology Facilities Council's £80 million deficit is a "myth", Ian Pearson'Nions, the director general for science and innovation, Pearson suggested that the £80m figure was more

Crowther, Paul

189

Infiltrating Mast Cells Correlate with Angiogenesis in Bone Metastases from Gastric Cancer Patients  

PubMed Central

While gastric cancer is a well established angiogenesis driven tumor, no data has been published regarding angiogenesis stimulated by mast cells (MCs) positive for tryptase in bone metastases from gastric cancer patients (BMGCP). It is well established that MCs play a role in immune responses and more recently it was demonstrated that MCs have been involved in tumor angiogenesis. We analyzed infiltrating MCs and neovascularization in BMGCP diagnosed by histology. A series of 15 stage T3-4N2-3M1 (by AJCC for Gastric Cancer Staging 7th Edition) BMGCP from bone biopsies were selected. Tumour tissue samples were evaluated by mean of immunohistochemistry and image analysis methods in terms of MCs density positive to tryptase (MCDPT), MCs area positive to tryptase (MCAPT), microvascular density (MVD) and endothelial area (EA). A significant correlation between MCDPT, MCAPT, MVD and EA groups to each other was found by Pearson and t-test analysis (r ranged from 0.68 to 0.82; p-value ranged from 0.00 to 0.02). Our very preliminary data suggest that infiltrating MCs positive for tryptase may play a role in BMGCP angiogenesis, and could be further evaluated as a novel target of anti-angiogenic therapy. PMID:25648323

Ammendola, Michele; Marech, Ilaria; Sammarco, Giuseppe; Zuccalà, Valeria; Luposella, Maria; Zizzo, Nicola; Patruno, Rosa; Crovace, Alberto; Ruggieri, Eustachio; Zito, Alfredo Francesco; Gadaleta, Cosmo Damiano; Sacco, Rosario; Ranieri, Girolamo

2015-01-01

190

Correlation between blood lead concentration and iron deficiency in Iranian children  

PubMed Central

Background: Iron deficiency anaemia is the most common nutritional anaemia among children. Lead toxicity is a serious health threat, especially in developing countries due to environmental pollution. It was thus aimed to investigate correlation between blood lead concentration and iron deficiency in children of Mashhad, Iran. Materials and Methods: This cross sectional study was performed on children between 1 year and 10 years, in Imam Reza teaching hospital of Mashhad, Iran, in 2010. Indeed during complete blood count (CBC), we measured iron and total iron binding capacity (TIBC) by colorimetric methods, ferritin by radioimmune assay and blood lead concentration by atomic absorption method. Results were analysed by Statistical Package for Social Sciences (SPSS) (version 11.5), using statistical tests including independent sample t-test, Mann-Whitney U test, Spearman's test and analysis of variance (ANOVA) and Pearson's or Spearman's correlation coefficient. P value ? 0.05 was considered as a significant level. Results: We studied 223 cases including 98 control children and 125 patients. All children had lead intoxication. Mean (±SD) blood lead concentration in the control group was 57.1 ± 25.3 (ranged 20-212) ?g/dl and in the patient group was 57 ± 20.4 (ranged 10.9-159) ?g/dl with no significant difference (P value = 0.713). We also did not find any correlation between blood lead concentration and haemoglobin, ferritin, iron, TIBC, mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), white blood cells (WBC) and platelets. Conclusion: Based on these results, no correlation was found between blood lead concentration and iron deficiency in the children. Because all children had lead intoxication, further studies in highly polluted and a comparison with a low polluted area are necessary to make a general conclusion. PMID:24403711

Keramati, Mohammad Reza; Manavifar, Lida; Badiee, Zahra; Sadeghian, Mohammad Hadi; Farhangi, Hamid; Mood, Mahdi Balali

2013-01-01

191

Correlation between changes in quality of life and symptomatic improvement in Chinese patients switched from typical antipsychotics to olanzapine  

PubMed Central

Purpose The aim of this study was to investigate the correlation between changes in symptoms and changes in self-reported quality of life among Chinese patients with schizophrenia who were switched from a typical antipsychotic to olanzapine during usual outpatient care. Patients and methods This post hoc analysis was conducted using data from the Chinese subgroup (n=475) of a multicountry, 12-month, prospective, noninterventional, observational study. The primary publication previously reported the efficacy, safety, and quality of life among patients who switched from a typical antipsychotic to olanzapine. Patients with schizophrenia were included if their symptoms were inadequately controlled with a typical antipsychotic and they were switched to olanzapine. Symptom severity was measured using the Brief Psychiatric Rating Scale (BPRS) and the Clinical Global Impressions-Severity scale (CGI-S). Health-Related Quality of Life (HRQOL) was assessed using the World Health Organization Quality of Life–Abbreviated (WHOQOL-BREF). Paired t-tests were performed to assess changes from baseline to endpoint. Pearson’s correlation coefficients (r) were used to assess the correlations between change in symptoms (BPRS and CGI-S scores) and change in HRQOL (WHOQOL-BREF scores). Results Symptoms and HRQOL both improved significantly over the 12 months of treatment (P<0.001). Significant correlations were observed between changes from baseline to end of study on the BPRS and the CGI-S and each of the WHOQOL-BREF four domain scores and two overall quality-of-life questions. The correlation coefficients ranged from r=?0.45 to r=?0.53 for the BPRS and WHOQOL-BREF. The correlation coefficients were slightly smaller between the CGI-S and WHOQOL-BREF, ranging from r=?0.33 to r=?0.40. Conclusion For patients with schizophrenia, assessing quality of life has the potential to add valuable information to the clinical assessment that takes into account the patient’s own perspective of well-being. PMID:25632235

Montgomery, William; Kadziola, Zbigniew; Ye, Wenye; Xue, Hai Bo; Liu, Li; Treuer, Tamás

2015-01-01

192

Interpreting the Distance Correlation Results for the COMBO-17 Survey  

NASA Astrophysics Data System (ADS)

The accurate classification of galaxies in large-sample astrophysical databases of galaxy clusters depends sensitively on the ability to distinguish between morphological types, especially at higher redshifts. This capability can be enhanced through a new statistical measure of association and correlation, called the distance correlation coefficient, which has more statistical power to detect associations than does the classical Pearson measure of linear relationships between two variables. The distance correlation measure offers a more precise alternative to the classical measure since it is capable of detecting nonlinear relationships that may appear in astrophysical applications. We showed recently that the comparison between the distance and Pearson correlation coefficients can be used effectively to isolate potential outliers in various galaxy data sets, and this comparison has the ability to confirm the level of accuracy associated with the data. In this work, we elucidate the advantages of distance correlation when applied to large databases. We illustrate how the distance correlation measure can be used effectively as a tool to confirm nonlinear relationships between various variables in the COMBO-17 database, including the lengths of the major and minor axes, and the alternative redshift distribution. For these outlier pairs, the distance correlation coefficient is routinely higher than the Pearson coefficient since it is easier to detect nonlinear relationships with distance correlation. The V-shaped scatter plots of Pearson versus distance correlation coefficients also reveal the patterns with increasing redshift and the contributions of different galaxy types within each redshift range.

Richards, Mercedes T.; Richards, Donald St. P.; Martínez-Gómez, Elizabeth

2014-04-01

193

A Correlation of Permanent Anterior Tooth Fracture with Type of Occlusion and Craniofacial Morphology  

PubMed Central

ABSTRACT Aims: To assess the relationship of anterior tooth fractures with type of occlusion and craniofacial morphology. Materials and methods: The study was conducted on 76 subjects of age group 9 to 13 years with at least one fractured permanent anterior teeth. Lateral cephalograms were taken and study models were prepared for each subject with prior consent of their parents. Then cephalometric tracings were done and overjet was recorded through study models. Statistical analysis used: Standard error of mean (SEM) and unpaired t-test has been applied to test the significant difference between the seven parameters under consideration. Karl Pearson correlation test has also been used to correlate all the parameters used in this study with each other. All the tests were performed at 5 and 1% levels of significance. Results: Frequency of tooth fracture increases with increasing overjet. At 5% level of significance, significant difference were observed between the standard values and observed values for overjet measurement, SNA angle, SNB angle, ANB angle, upper incisor to NA (angle), upper incisor to NA (linear) and interincisal angle for overall data and also for both male and female data separately. Conclusion: Probability of permanent anterior tooth fracture increases with increasing overjet. A significant difference was observed between the standard value and the observed values of all parameters under consideration. How to cite this article: Chaturvedi R, Kumar A, Rana V, Aggarwal A, Chandra L. A Correlation of Permanent Anterior Tooth Fracture with Type of Occlusion and Craniofacial Morphology. Int J Clin Pediatr Dent 2013;6(2):80-84. PMID:25206197

Kumar, Ashish; Rana, Vivek; Aggarwal, Abhai; Chandra, Lokesh

2013-01-01

194

A Pearson VII distribution function for fast calculation of dechanneling and angular dispersion of beams  

NASA Astrophysics Data System (ADS)

Although multiple scattering theories have been well developed, numerical calculation is complicated and only tabulated values have been available, which has caused inconvenience in practical use. We have found that a Pearson VII distribution function can be used to fit Lugujjo and Mayer's probability curves in describing the dechanneling phenomenon in backscattering analysis, over a wide range of disorder levels. Differentiation of the obtained function gives another function to calculate angular dispersion of the beam in the frameworks by Sigmund and Winterbon. The present work provides an easy calculation of both dechanneling probability and angular dispersion for any arbitrary combination of beam and target having a reduced thickness ?0.6, which can be implemented in modeling of channeling spectra. Furthermore, we used a Monte Carlo simulation program to calculate the deflection probability and compared them with previously tabulated data. A good agreement was reached.

Shao, Lin; Peng, Luohan

2009-12-01

195

Pearson marrow pancreas syndrome in patients suspected to have Diamond-Blackfan anemia.  

PubMed

Pearson marrow pancreas syndrome (PS) is a multisystem disorder caused by mitochondrial DNA (mtDNA) deletions. Diamond-Blackfan anemia (DBA) is a congenital hypoproliferative anemia in which mutations in ribosomal protein genes and GATA1 have been implicated. Both syndromes share several features including early onset of severe anemia, variable nonhematologic manifestations, sporadic genetic occurrence, and occasional spontaneous hematologic improvement. Because of the overlapping features and relative rarity of PS, we hypothesized that some patients in whom the leading clinical diagnosis is DBA actually have PS. Here, we evaluated patient DNA samples submitted for DBA genetic studies and found that 8 (4.6%) of 173 genetically uncharacterized patients contained large mtDNA deletions. Only 2 (25%) of the patients had been diagnosed with PS on clinical grounds subsequent to sample submission. We conclude that PS can be overlooked, and that mtDNA deletion testing should be performed in the diagnostic evaluation of patients with congenital anemia. PMID:24735966

Gagne, Katelyn E; Ghazvinian, Roxanne; Yuan, Daniel; Zon, Rebecca L; Storm, Kelsie; Mazur-Popinska, Magdalena; Andolina, Laura; Bubala, Halina; Golebiowska, Sydonia; Higman, Meghan A; Kalwak, Krzysztof; Kurre, Peter; Matysiak, Michal; Niewiadomska, Edyta; Pels, Salley; Petruzzi, Mary Jane; Pobudejska-Pieniazek, Aneta; Szczepanski, Tomasz; Fleming, Mark D; Gazda, Hanna T; Agarwal, Suneet

2014-07-17

196

Fisher, Neyman-Pearson or NHST? A tutorial for teaching data testing.  

PubMed

Despite frequent calls for the overhaul of null hypothesis significance testing (NHST), this controversial procedure remains ubiquitous in behavioral, social and biomedical teaching and research. Little change seems possible once the procedure becomes well ingrained in the minds and current practice of researchers; thus, the optimal opportunity for such change is at the time the procedure is taught, be this at undergraduate or at postgraduate levels. This paper presents a tutorial for the teaching of data testing procedures, often referred to as hypothesis testing theories. The first procedure introduced is Fisher's approach to data testing-tests of significance; the second is Neyman-Pearson's approach-tests of acceptance; the final procedure is the incongruent combination of the previous two theories into the current approach-NSHT. For those researchers sticking with the latter, two compromise solutions on how to improve NHST conclude the tutorial. PMID:25784889

Perezgonzalez, Jose D

2015-01-01

197

Fisher, Neyman-Pearson or NHST? A tutorial for teaching data testing  

PubMed Central

Despite frequent calls for the overhaul of null hypothesis significance testing (NHST), this controversial procedure remains ubiquitous in behavioral, social and biomedical teaching and research. Little change seems possible once the procedure becomes well ingrained in the minds and current practice of researchers; thus, the optimal opportunity for such change is at the time the procedure is taught, be this at undergraduate or at postgraduate levels. This paper presents a tutorial for the teaching of data testing procedures, often referred to as hypothesis testing theories. The first procedure introduced is Fisher's approach to data testing—tests of significance; the second is Neyman-Pearson's approach—tests of acceptance; the final procedure is the incongruent combination of the previous two theories into the current approach—NSHT. For those researchers sticking with the latter, two compromise solutions on how to improve NHST conclude the tutorial. PMID:25784889

Perezgonzalez, Jose D.

2015-01-01

198

Pearson disease in an infant presenting with severe hypoplastic anemia, normal pancreatic function, and progressive liver failure.  

PubMed

Pearson disease is a rare, usually fatal, mitochondrial disorder affecting primarily the bone marrow and the exocrine pancreas. We report a previously healthy 10-week-old girl who presented with profound macrocytic anemia followed by pancytopenia, synthetic liver dysfunction with liver steatosis, and metabolic acidosis with high lactate levels. She had no pancreatic involvement. Multiple cytoplasmic vacuoles in myelocytes and monocytes were seen upon microscopic evaluation of the bone marrow. Genetic analysis of the mitochondrial genome revealed a 5 kbp deletion, thus establishing the diagnosis of Pearson disease. PMID:23588341

Shapira, Adi; Konopnicki, Muriel; Hammad-Saied, Mohammed; Shabad, Evelyn

2014-07-01

199

Anatomical structural network analysis of human brain using partial correlations of gray matter volumes  

Microsoft Academic Search

Structural connectivity in human brain has been studied by modeling the statistical dependence between features of cortical regions, such as gray matter thickness. Statistical correlations between gray matter thickness have been mainly used as a metric to study this dependence. In this paper, we propose the use of partial correlations instead of Pearson correlation for inferring the brain structural connectivity

Anand A. Joshi; Shantanu H. Joshi; Ivo D. Dinov; David W. Shattuck; Richard M. Leahy; Arthur W. Toga

2010-01-01

200

An Inequality between the Weighted Average and the Rowwise Correlation Coefficient for Proximity Matrices.  

ERIC Educational Resources Information Center

To assess association between rows of proximity matrices, H. de Vries (1993) introduces weighted average and row-wise average variants for Pearson's product-moment correlation, Spearman's rank correlation, and Kendall's rank correlation. For all three, the absolute value of the first variant is greater than or equal to the second. (SLD)

Krijnen, Wim P.

1994-01-01

201

Spectroscopy of Francium Isotopes J. S. Grossman, L. A. Orozco, M. R. Pearson and G. D. Sprouse  

E-print Network

Spectroscopy of Francium Isotopes J. S. Grossman, L. A. Orozco, M. R. Pearson and G. D. Sprouse Abstract We have performed precision spectroscopy on cold francium atoms in a magneto optical trap. Our®ne splitting in a chain of neutron de®cient francium isotopes. 1. Introduction Francium is the heaviest

Orozco, Luis A.

202

A Pearson Random Walk with Steps of Uniform Orientation and Dirichlet Distributed Lengths  

NASA Astrophysics Data System (ADS)

A constrained diffusive random walk of n steps in ? d and a random flight in ? d , which are equivalent, were investigated independently in recent papers (J. Stat. Phys. 127:813, 2007; J. Theor. Probab. 20:769, 2007, and J. Stat. Phys. 131:1039, 2008). The n steps of the walk are independent and identically distributed random vectors of exponential length and uniform orientation. Conditioned on the sum of their lengths being equal to a given value l, closed-form expressions for the distribution of the endpoint of the walk were obtained altogether for any n for d=1,2,4. Uniform distributions of the endpoint inside a ball of radius l were evidenced for a walk of three steps in 2D and of two steps in 4D. The previous walk is generalized by considering step lengths which have independent and identical gamma distributions with a shape parameter q>0. Given the total walk length being equal to 1, the step lengths have a Dirichlet distribution whose parameters are all equal to q. The walk and the flight above correspond to q=1. Simple analytical expressions are obtained for any d?2 and n?2 for the endpoint distributions of two families of walks whose q are integers or half-integers which depend solely on d. These endpoint distributions have a simple geometrical interpretation. Expressed for a two-step planar walk whose q=1, it means that the distribution of the endpoint on a disc of radius 1 is identical to the distribution of the projection on the disc of a point M uniformly distributed over the surface of the 3D unit sphere. Five additional walks, with a uniform distribution of the endpoint in the inside of a ball, are found from known finite integrals of products of powers and Bessel functions of the first kind. They include four different walks in ?3, two of two steps and two of three steps, and one walk of two steps in ?4. Pearson-Liouville random walks, obtained by distributing the total lengths of the previous Pearson-Dirichlet walks according to some specified probability law are finally discussed. Examples of unconstrained random walks, whose step lengths are gamma distributed, are more particularly considered.

Le Caër, Gérard

2010-08-01

203

Pearson's principle inspired generalized strategy for the fabrication of metal hydroxide and oxide nanocages.  

PubMed

Designing a general route for rational synthesis of a series or families of nanomaterials for emerging applications has become more and more fascinating and vital in the view of nanoscience and nanotechnology. Herein, we explore a general strategy for fabricating uniform nanocages of metal hydroxides (MHs) and metal oxides (MOs). A template-assisted route inspired by Pearson's hard and soft acid-base (HSAB) principle was employed for synthesizing MH nanocages via meticulous selection of the coordinating etchant as well as optimization of the reaction conditions. The concept of "coordinating etching" is successfully achieved in this work. This unique route shows potential in designing well-defined and high-quality MH nanocages with varying components, shell thicknesses, shapes, and sizes at room temperature. Consequently, porous MO nanocages can be obtained readily just through appropriate thermal treament of the respective MH nanocages. The overall strategy present in this work extends the application of the HSAB principle in nanoscience and offers a unqiue clue for rational fabrication of hollow (porous) and/or amorphous structures on the nanoscale, where these nanocages may present promising potential for various applications. PMID:23724779

Nai, Jianwei; Tian, Yu; Guan, Xin; Guo, Lin

2013-10-30

204

Log Pearson type 3 quantile estimators with regional skew information and low outlier adjustments  

USGS Publications Warehouse

[1] The recently developed expected moments algorithm (EMA) [Cohn et al., 1997] does as well as maximum likelihood estimations at estimating log-Pearson type 3 (LP3) flood quantiles using systematic and historical flood information. Needed extensions include use of a regional skewness estimator and its precision to be consistent with Bulletin 17B. Another issue addressed by Bulletin 17B is the treatment of low outliers. A Monte Carlo study compares the performance of Bulletin 17B using the entire sample with and without regional skew with estimators that use regional skew and censor low outliers, including an extended EMA estimator, the conditional probability adjustment (CPA) from Bulletin 17B, and an estimator that uses probability plot regression (PPR) to compute substitute values for low outliers. Estimators that neglect regional skew information do much worse than estimators that use an informative regional skewness estimator. For LP3 data the low outlier rejection procedure generally results in no loss of overall accuracy, and the differences between the MSEs of the estimators that used an informative regional skew are generally modest in the skewness range of real interest. Samples contaminated to model actual flood data demonstrate that estimators which give special treatment to low outliers significantly outperform estimators that make no such adjustment.

Griffis, V.W.; Stedinger, J.R.; Cohn, T.A.

2004-01-01

205

Testing Dependent Correlations with Nonoverlapping Variables: A Monte Carlo Simulation  

ERIC Educational Resources Information Center

The authors conducted a Monte Carlo simulation of 4 test statistics or comparing dependent correlations with no variables in common. Empirical Type 1 error rates and power estimates were determined for K. Pearson and L. N. G. Filon's (1898) z, O. J. Dunn and V. A. Clark's (1969) z, J. H. Steiger's (1980) original modification of Dunn and Clark's…

Silver, N. Clayton; Hittner, James B.; May, Kim

2004-01-01

206

Effect of degree correlations above the first shell on the percolation transition  

NASA Astrophysics Data System (ADS)

The use of degree-degree correlations to model realistic networks which are characterized by their Pearson's coefficient, has become widespread. However the effect on how different correlation algorithms produce different results on processes on top of them, has not yet been discussed. In this letter, using different correlation algorithms to generate assortative networks, we show that for very assortative networks the behavior of the main observables in percolation processes depends on the algorithm used to build the network. The different alghoritms used here introduce different inner structures that are missed in Pearson's coefficient. We explain the different behaviors through a generalization of Pearson's coefficient that allows to study the correlations at chemical distances l from a root node. We apply our findings to real networks.

Valdez, L. D.; Buono, C.; Braunstein, L. A.; Macri, P. A.

2011-11-01

207

Gene interaction networks based on kernel correlation metrics.  

PubMed

In this paper, a Kernel correlation coefficient (KCC) method is proposed to elucidate the gene nonlinear relationships as a distance metric. To evaluate the performance of this nonlinear distance measure, a biological network of the Gaussian Kernel on a public dataset of yeast genes is constructed by using a graph theory. Specifically, the distribution and properties of this new measure are analysed and compared with the classical Pearson correlation method. The reliability and advantages of our proposed Kernel correlation metric is verified and shown formally on ten showcases of the DREAM (Dialogue for Reverse Engineering Assessments and Methods) project. Test experiment results demonstrate that the proposed Kernel correlation coefficient measure has a strong capability in identifying interaction genes, and that the proposed method can detect accurately the key genes and functional interactions (also known as the cliques) as compared to the commonly used Pearson correlation and Mutual Information measures. PMID:23428475

Cheng, Lijun; Khorasani, K; Ding, Yongsheng; Guo, Xihong

2013-01-01

208

The Pearson-Readhead Survey of Compact Extragalactic Radio Sources From Space. I. The Images  

E-print Network

We present images from a space-VLBI survey using the facilities of the VLBI Space Observatory Programme (VSOP), drawing our sample from the well-studied Pearson-Readhead survey of extragalactic radio sources. Our survey has taken advantage of long space-VLBI baselines and large arrays of ground antennas, such as the Very Long Baseline Array and European VLBI Network, to obtain high resolution images of 27 active galactic nuclei, and to measure the core brightness temperatures of these sources more accurately than is possible from the ground. A detailed analysis of the source properties is given in accompanying papers. We have also performed an extensive series of simulations to investigate the errors in VSOP images caused by the relatively large holes in the (u,v) plane when sources are observed near the orbit normal direction. We find that while the nominal dynamic range (defined as the ratio of map peak to off-source error) often exceeds 1000:1, the true dynamic range (map peak to on-source error) is only about 30:1 for relatively complex core-jet sources. For sources dominated by a strong point source, this value rises to approximately 100:1. We find the true dynamic range to be a relatively weak function of the difference in position angle (PA) between the jet PA and (u,v) coverage major axis PA. For low signal-to-noise regions typically located down the jet away from the core, large errors can occur, causing spurious features in VSOP images that should be interpreted with caution.

M. L. Lister; S. J. Tingay; D. W. Murphy; B. G. Piner; D. L. Jones; R. A. Preston

2001-02-15

209

Filter design for the detection of compact sources based on the Neyman-Pearson detector  

E-print Network

This paper considers the problem of compact source detection on a Gaussian background in 1D. Two aspects of this problem are considered: the design of the detector and the filtering of the data. Our detection scheme is based on local maxima and it takes into account not only the amplitude but also the curvature of the maxima. A Neyman-Pearson test is used to define the region of acceptance, that is given by a sufficient linear detector that is independent on the amplitude distribution of the sources. We study how detection can be enhanced by means of linear filters with a scaling parameter and compare some of them (the Mexican Hat wavelet, the matched and the scale-adaptive filters). We introduce a new filter, that depends on two free parameters (biparametric scale-adaptive filter). The value of these two parameters can be determined, given the a priori pdf of the amplitudes of the sources, such that the filter optimizes the performance of the detector in the sense that it gives the maximum number of real detections once fixed the number density of spurious sources. The combination of a detection scheme that includes information on the curvature and a flexible filter that incorporates two free parameters (one of them a scaling) improves significantly the number of detections in some interesting cases. In particular, for the case of weak sources embedded in white noise the improvement with respect to the standard matched filter is of the order of 40%. Finally, an estimation of the amplitude of the source is introduced and it is proven that such an estimator is unbiased and it has maximum efficiency. We perform numerical simulations to test these theoretical ideas and conclude that the results of the simulations agree with the analytical ones.

M. Lopez-Caniego; D. Herranz; R. B. Barreiro; J. L. Sanz

2005-04-11

210

Excursions in Modern Mathematics, 7e: 3.3 -1Copyright 2010 Pearson Education, Inc. 3 The Mathematics of Sharing  

E-print Network

Pearson Education, Inc. Is this fair? ! Cleo receives at least 1/3 of the value of the cake (as perceived their value system on the game.! ! Generally, the analysis of fair division games with three or more players The Mathematics of Sharing 3.1 Fair-Division Games 3.2 Two Players: The Divider-Chooser Method 3.3 The Lone

Lee, Carl

211

Correlation of Point B and Lymph Node Dose in 3D-Planned High-Dose-Rate Cervical Cancer Brachytherapy  

SciTech Connect

Purpose: To compare high dose rate (HDR) point B to pelvic lymph node dose using three-dimensional-planned brachytherapy for cervical cancer. Methods and Materials: Patients with FIGO Stage IB-IIIB cervical cancer received 70 tandem HDR applications using CT-based treatment planning. The obturator, external, and internal iliac lymph nodes (LN) were contoured. Per fraction (PF) and combined fraction (CF) right (R), left (L), and bilateral (Bil) nodal doses were analyzed. Point B dose was compared with LN dose-volume histogram (DVH) parameters by paired t test and Pearson correlation coefficients. Results: Mean PF and CF doses to point B were R 1.40 Gy +- 0.14 (CF: 7 Gy), L 1.43 +- 0.15 (CF: 7.15 Gy), and Bil 1.41 +- 0.15 (CF: 7.05 Gy). The correlation coefficients between point B and the D100, D90, D50, D2cc, D1cc, and D0.1cc LN were all less than 0.7. Only the D2cc to the obturator and the D0.1cc to the external iliac nodes were not significantly different from the point B dose. Significant differences between R and L nodal DVHs were seen, likely related to tandem deviation from irregular tumor anatomy. Conclusions: With HDR brachytherapy for cervical cancer, per fraction nodal dose approximates a dose equivalent to teletherapy. Point B is a poor surrogate for dose to specific nodal groups. Three-dimensional defined nodal contours during brachytherapy provide a more accurate reflection of delivered dose and should be part of comprehensive planning of the total dose to the pelvic nodes, particularly when there is evidence of pathologic involvement.

Lee, Larissa J. [Harvard Radiation Oncology Program, Brigham and Women's Hospital, Boston, MA (United States); Sadow, Cheryl A. [Department of Radiology, Brigham and Women's Hospital, Boston, MA (United States); Russell, Anthony [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Viswanathan, Akila N., E-mail: aviswanathan@lroc.harvard.ed [Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA (United States)

2009-11-01

212

All procedures were approved by the Princeton University Institutional Animal Care and Use Committee and were in compliance with the Guide for the Care and Use of Laboratory Animals  

E-print Network

Committee and were in compliance with the Guide for the Care and Use of Laboratory Animals (http://www.nap are from Pearson's correlation, p values reflect unpaired two-tailed Student's t-tests, and data

Pillow, Jonathan

213

Covariate Adjusted Correlation Analysis with Application to FMR1 Premutation Female Carrier Data  

E-print Network

premutation carriers of the fragile X mental retardation 1 (FMR1) gene, we present a new method of covariate; Mental retardation; Nonparametric partial correlation; Pearson correlation; Semipara- metric modeling X mental retardation 1 (FMR1) X-linked gene (Verkerk et al., 1991; Oberle et al., 1991). When

Sentürk, Damla

214

Distribution of the Maximum of the Arithmetic Mean of Correlated Random Variables  

Microsoft Academic Search

The initial distribution considered here is obtained from a multivariate analogue of the Pearson Type III distribution, and the value of the correlation is taken to be non-negative. There is obtained here the distribution of the maximum in samples of fixed size $n$ from a random variable which is the arithmetic mean of $k$ such correlated random variables. This distribution

John Gurland

1955-01-01

215

Distance Correlation Methods for Discovering Associations in Large Astrophysical Databases  

NASA Astrophysics Data System (ADS)

High-dimensional, large-sample astrophysical databases of galaxy clusters, such as the Chandra Deep Field South COMBO-17 database, provide measurements on many variables for thousands of galaxies and a range of redshifts. Current understanding of galaxy formation and evolution rests sensitively on relationships between different astrophysical variables; hence an ability to detect and verify associations or correlations between variables is important in astrophysical research. In this paper, we apply a recently defined statistical measure called the distance correlation coefficient, which can be used to identify new associations and correlations between astrophysical variables. The distance correlation coefficient applies to variables of any dimension, can be used to determine smaller sets of variables that provide equivalent astrophysical information, is zero only when variables are independent, and is capable of detecting nonlinear associations that are undetectable by the classical Pearson correlation coefficient. Hence, the distance correlation coefficient provides more information than the Pearson coefficient. We analyze numerous pairs of variables in the COMBO-17 database with the distance correlation method and with the maximal information coefficient. We show that the Pearson coefficient can be estimated with higher accuracy from the corresponding distance correlation coefficient than from the maximal information coefficient. For given values of the Pearson coefficient, the distance correlation method has a greater ability than the maximal information coefficient to resolve astrophysical data into highly concentrated horseshoe- or V-shapes, which enhances classification and pattern identification. These results are observed over a range of redshifts beyond the local universe and for galaxies from elliptical to spiral.

Martínez-Gómez, Elizabeth; Richards, Mercedes T.; Richards, Donald St. P.

2014-01-01

216

Filter design for the detection of compact sources based on the Neyman-Pearson detector  

NASA Astrophysics Data System (ADS)

This paper considers the problem of compact source detection on a Gaussian background. We present a one-dimensional treatment (though a generalization to two or more dimensions is possible). Two relevant aspects of this problem are considered: the design of the detector and the filtering of the data. Our detection scheme is based on local maxima and it takes into account not only the amplitude but also the curvature of the maxima. A Neyman-Pearson test is used to define the region of acceptance, which is given by a sufficient linear detector that is independent of the amplitude distribution of the sources. We study how detection can be enhanced by means of linear filters with a scaling parameter, and compare some filters that have been proposed in the literature [the Mexican hat wavelet, the matched filter (MF) and the scale-adaptive filter (SAF)]. We also introduce a new filter, which depends on two free parameters (the biparametric scale-adaptive filter, BSAF). The value of these two parameters can be determined, given the a priori probability density function of the amplitudes of the sources, such that the filter optimizes the performance of the detector in the sense that it gives the maximum number of real detections once it has fixed the number density of spurious sources. The new filter includes as particular cases the standard MF and the SAF. As a result of its design, the BSAF outperforms these filters. The combination of a detection scheme that includes information on the curvature and a flexible filter that incorporates two free parameters (one of them a scaling parameter) improves significantly the number of detections in some interesting cases. In particular, for the case of weak sources embedded in white noise, the improvement with respect to the standard MF is of the order of 40 per cent. Finally, an estimation of the amplitude of the source (most probable value) is introduced and it is proven that such an estimator is unbiased and has maximum efficiency. We perform numerical simulations to test these theoretical ideas in a practical example and conclude that the results of the simulations agree with the analytical results.

López-Caniego, M.; Herranz, D.; Barreiro, R. B.; Sanz, J. L.

2005-05-01

217

SweConsNet'02 The 1st SweConsNet Workshop Pierre Flener and Justin Pearson, ASTRA, Uppsala Univ. Page 1 of 19 Relational Modelling of CSPs  

E-print Network

SweConsNet'02 ­ The 1st SweConsNet Workshop Pierre Flener and Justin Pearson, ASTRA, Uppsala Univ Flener and Justin Pearson, ASTRA, Uppsala Univ. Page 2 of 19 Members · Dr Pierre Flener, Department of Information Technology, principal investigator · Dr Justin Pearson, Department of Information Technology · Mr

Flener, Pierre

218

Simon, N. S. C., Davies, G. R., Pearson, D. G. & Carlson, R. W. (2004). The southern African Kaapvaal craton: formation and modification of continental lithospheric mantle in Archaean subduction zones?  

E-print Network

Simon, N. S. C., Davies, G. R., Pearson, D. G. & Carlson, R. W. (2004). The southern African , D.G. PEARSON 2 AND R.W. CARLSON 3 1 FALW, VU Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, UK; d.g.pearson@durham.ac.uk 3 DTM, Carnegie Inst. Washington, 5241 Broad Branch Road N

Simon, Nina

219

Craig Pearson an d Rod Whitaker (LANL ), Jessie Bonner (Weston Geophys ics),Terry Wallace (UofArizona), Diane Doser (UT El Paso), Phelps -Dodge Morenci and Tyrone, Paul Loeffler (Texas General Land Office).  

E-print Network

THANKS Craig Pearson an d Rod Whitaker (LANL ), Jessie Bonner (Weston Geophys ics),Terry Wallace. THANKSTHANKS Craig Pearson an d Rod Whitaker (LANL ), Jessie Bonner (Weston Geophys ical), Terry Wallace (U of Arizona),Craig Pearson and Rod Whitaker (LANL ), Jessie Bonner (Weston Geophys ical), Terry Wallace (U

Stump, Brian W.

220

103:2938-2952, 2010. First published Mar 31, 2010; doi:10.1152/jn.01089.2009J Neurophysiol Toni S. Pearson, John W. Krakauer and Pietro Mazzoni  

E-print Network

. Pearson, John W. Krakauer and Pietro Mazzoni You might find this additional information useful... 40 Not to Generalize: Modular Adaptation of Visuomotor Gain Toni S. Pearson, John W. Krakauer, and Pietro Mazzoni Motor York Submitted 11 December 2009; accepted in final form 30 March 2010 Pearson TS, Krakauer JW, Mazzoni

221

Measurement of Waist and Hip Circumference with a Body Surface Scanner: Feasibility, Validity, Reliability, and Correlations with Markers of the Metabolic Syndrome  

PubMed Central

Objective Body surface scanners (BS), which visualize a 3D image of the human body, facilitate the computation of numerous body measures, including height, waist circumference (WC) and hip circumference (HC). However, limited information is available regarding validity and reliability of these automated measurements (AM) and their correlation with parameters of the Metabolic Syndrome (MetS) compared to traditional manual measurements (MM). Methods As part of a cross-sectional feasibility study, AM of WC, HC and height were assessed twice in 60 participants using a 3D BS (VitussmartXXL). Additionally, MM were taken by trained personnel according to WHO guidelines. Participants underwent an interview, bioelectrical impedance analysis, and blood pressure measurement. Blood samples were taken to determine HbA1c, HDL-cholesterol, triglycerides, and uric acid. Validity was assessed based on the agreement between AM and MM, using Bland-Altman-plots, correlation analysis, and paired t-tests. Reliability was assessed using intraclass correlation coefficients (ICC) based on two repeated AM. Further, we calculated age-adjusted Pearson correlation for AM and MM with fat mass, systolic blood pressure, HbA1c, HDL-cholesterol, triglycerides, and uric acid. Results Body measures were higher in AM compared to MM but both measurements were strongly correlated (WC, men, difference = 1.5cm, r = 0.97; women, d = 4.7cm, r = 0.96; HC, men, d = 2.3cm, r = 0.97; women, d = 3.0cm; r = 0.98). Reliability was high for all AM (nearly all ICC>0.98). Correlations of WC, HC, and the waist-to-hip ratio (WHR) with parameters of MetS were similar between AM and MM; for example the correlation of WC assessed by AM with HDL-cholesterol was r = 0.35 in men, and r = -0.48 in women, respectively whereas correlation of WC measured manually with HDL cholesterol was r = -0.41 in men, and r = -0.49 in women, respectively. Conclusions Although AM of WC, HC, and WHR are higher when compared to MM based on WHO guidelines, our data indicate good validity, excellent reliability, and similar correlations to parameters of the MetS. PMID:25749283

Jaeschke, Lina; Steinbrecher, Astrid; Pischon, Tobias

2015-01-01

222

On the correlation of a naturally and an artificially dichotomized variable.  

PubMed

A method is suggested for estimating the correlation of a naturally (X) and an artificially (Y) dichotomized variable. It is assumed that a normal random variable (L) underlies the artificially dichotomized variable. The proposed correlation coefficient recovers the product moment correlation coefficient between X and L from a fourfold table of X and Y. The suggested correlation coefficient nu is contrasted with the phi correlation and the biserial eta. The biserial eta was proposed by Karl Pearson and is conceptually related to the new correlation coefficient. However, in addition, Pearson's biserial eta invokes the assumption that the marginal distribution of L is normal, which contradicts its basic assumptions and thus does not recover the true correlation of L and X. Finally, an approximation is provided to simplify the calculation of nu and its standard error. PMID:15511306

Ulrich, Rolf; Wirtz, Markus

2004-11-01

223

Generalized Pearson-Fisher Chi-Square Goodness-of-Fit Tests, with Applications to Models with Life History Data  

Microsoft Academic Search

Suppose that $X_1,\\\\ldots,X_n$ are i.i.d. $\\\\sim F$, and we wish to test the null hypothesis that $F$ is a member of the parametric family $\\\\mathscr{F} = \\\\{F_\\\\theta(x); \\\\theta \\\\in \\\\Theta\\\\}$ where $\\\\Theta \\\\subset \\\\mathbb{R}^q$. The classical Pearson-Fisher chi-square test involves partitioning the real axis into $k$ cells $I_1,\\\\ldots, I_k$ and forming the chi-square statistic $X^2 = \\\\sum^k_{i = 1}(O_i -

Gang Li; Hani Doss

1993-01-01

224

Odontometric Sexual Dimorphism: A Sibling Correlation  

PubMed Central

Aims and Background: Teeth form an excellent material for anthropological, genetic, odontologic and forensic investigations. The aim of this study was to establish the genetic control of sexual dimorphism in tooth size amongst siblings of Goan children in age range of 14-22 years. Materials and Methods: Twenty-two sibling pairs were selected (22 males and 22 females) to assess genetic control of sexual dimorphism in tooth size. Alginate impressions were obtained for maxillary and mandibular arches and study models were prepared. Measurements were done using Zoom Digimatic Vernier Calipers with a resolution of 0.01 mm. Statistical Analysis: Correlation between mesiodistal and buccolingual tooth sizes amongst siblings was calculated using Pearson’s correlation coefficient. Results: A statistically significant association was found between Mesiodistal Widths of Permanent Maxillary Right and Left Second Molars and between Maxillary Right and Left First Premolars amongst sibling pairs. A statistically significant association was also found between Buccolingual Widths of Mandibular Right and Left First Premolars amongst sibling pairs. This statistically significant correlation found amongst siblings establishes a genetic control over sexual dimorphism in these teeth. Conclusion: The genetic basis of sexual dimorphism in human dentition was ascertained as a significant correlation was found between mesio-distal and bucco-lingual widths of premolars between sibling pairs. PMID:24783145

Sharma, Sonali; Dinkar, Ajit D.; Bedi, Sumit

2014-01-01

225

Measurement of the internal adaptation of resin composites using micro-CT and its correlation with polymerization shrinkage.  

PubMed

In the present study, the internal adaptation of dentin-composite interfaces with various resin composite materials under conditions of thermomechanical loading was analyzed nondestructively using micro-computed tomography (micro-CT), and these results were compared with analyses of microgaps after sectioning. Additionally, the correlation of internal adaptation with polymerization shrinkage strain and stress was evaluated. Four nonflowable resins, Gradia Direct (GD), Filtek P90 (P9), Filtek Z350 (Z3), and Charisma (CH), and two flowable resins, SDR (SD) and Tetric N-Flow (TF) were used. First, the polymerization shrinkage strain and stress were measured. Then, Class I cavities were prepared in 48 premolars. They were divided randomly into six groups, and the cavities were filled with composites using XP bond. To evaluate the internal adaptation, tooth specimens were immersed in a 25% silver nitrate solution, and micro-CT analysis was performed before and after thermomechanical loading. The silver nitrate penetration (%SP) was measured. After buccolingual sectioning and rhodamine penetration of the specimen, the rhodamine penetration (%RP) was measured using a stereo-microscope. One-way analysis of variance was then used to compare the polymerization shrinkage strain, stress, %SP, and %RP among the groups at a 95% confidence level. A paired t-test was used to compare the %SP before and after thermomechanical loading. Pearson correlation analysis was used to compare the correlation between polymerization shrinkage strain/stress and %SP or %RP to a 95% confidence level. Evaluation of the polymerization shrinkage strain demonstrated that P9 < Z3 ? GD < CH ? SD < TF (p<0.05); similarly, evaluation of the polymerization shrinkage stress showed that P9 ? GD ? Z3 ? CH ? SD < TF (p<0.05). The %SP showed that P9 ? GD ? Z3 < CH ? SD < TF (p<0.05) before loading and that P9 ? GD ? Z3 ? CH ? SD < TF (p<0.05) after loading. There was a significant difference between the before-loading and after-loading measurements in all groups (p<0.05). Additionally, there was a positive correlation between the %SP and the %RP (r=0.810, p<0.001). Conclusively, the polymerization shrinkage stress and strain were found to be closely related to the internal adaptation of the resin composite restorations. The newly proposed model for the evaluation of internal adaptation using micro-CT and silver nitrate may provide a new measurement for evaluating the internal adaptation of restorations in a nondestructive way. PMID:24111809

Kim, H J; Park, S H

2014-01-01

226

A Relationship Between the 2-body Energy of Kaxiras Pandey and Pearson Takai Halicioglu Tiller Potential Functions  

NASA Astrophysics Data System (ADS)

A parametric relationship between the Pearson Takai Halicioglu Tiller (PTHT) and the Kaxiras Pandey (KP) empirical potential energy functions is developed for the case of 2-body interaction. The need for such relationship arises when preferred parametric data and adopted software correspond to different potential functions. The analytical relationship was obtained by equating the potential functions' derivatives at zeroth, first and second order with respect to the interatomic distance at the equilibrium bond length, followed by comparison of coefficients in the repulsive and attractive terms. Plots of non-dimensional 2-body energy versus the nondimensional interatomic distance verified the analytical relationships developed herein. The discrepancy revealed in theoretical plots suggests that the 2-body PTHT and KP potentials are more suitable for curve-fitting "softer" and "harder" bonds respectively.

Lim, Teik-Cheng

2004-01-01

227

Novel 5.712 kb mitochondrial DNA deletion in a patient with Pearson syndrome: A case report.  

PubMed

Pearson marrow?pancreas syndrome (PS) is a progressive multi?organ disorder caused by deletions and duplications of mitochondrial DNA (mtDNA). PS is often fatal in infancy, and the majority of patients with PS succumb to the disease before reaching three?years?of?age, due to septicemia, metabolic acidosis or hepatocellular insufficiency. The present report describes the case of a four?month?old infant with severe normocytic normochromic anemia, vacuolization of hematopoietic precursors and metabolic acidosis. After extensive clinical investigation, the patient was diagnosed with PS, which was confirmed by molecular analysis of mtDNA. The molecular analysis detected a novel large?scale (5.712 kb) deletion spanning nucleotides 8,011 to 13,722 of mtDNA, which lacked direct repeats at the deletion boundaries. The present report is, to the best of our knowledge, the first case reported in South Korea. PMID:25543536

Park, Joonhong; Ryu, Hyejin; Jang, Woori; Chae, Hyojin; Kim, Myungshin; Kim, Yonggoo; Kim, Jiyeon; Lee, Jae Wook; Chung, Nack-Gyun; Cho, Bin; Suh, Byung Kyu

2015-05-01

228

Cost consequences of point-of-care troponin T testing in a Swedish primary health care setting  

PubMed Central

Abstract Objective. To evaluate the safety and cost-effectiveness of point-of-care troponin T testing (POCT-TnT) for the management of patients with chest pain in primary care. Design. Prospective observational study with follow-up. Setting. Three primary health care (PHC) centres using POCT-TnT and four PHC centres not using POCT-TnT in south-east Sweden. Patients. All patients ? 35 years of age, contacting one of the PHC centres for chest pain, dyspnoea on exertion, unexplained weakness and/or fatigue, with no other probable cause than cardiac, were included. Symptoms must have commenced or worsened during the previous seven days. Main outcome measures. Emergency referral rates, diagnoses of acute myocardial infarction (AMI) or unstable angina (UA), and costs were collected for 30 days after the patient sought care at the PHC centre. Results. A total of 196 patients with chest pain were included: 128 in PHC centres with POCT-TnT and 68 in PHC centres without POCT-TnT. Fewer patients from the PHC centres with POCT-TnT (n = 32, 25%) were emergently referred to hospital than from centres without POCT-TnT (n = 29, 43%; p = 0.011). Eight patients (6.2%) from PHC centres with POCT-TnT were diagnosed with AMI or UA compared with six patients (8.8%) from centres without POCT-TnT (p = 0.565). Two patients with AMI or UA were classified as missed cases from PHC centres with POCT-TnT and there were no missed cases from PHC centres without POCT-TnT. SKr290 000 was saved per missed case of AMI or UA. Conclusion. The use of POCT-TnT in primary care may be cost saving but at the expense of missed cases. PMID:25434410

Andersson, Agneta; Janzon, Magnus; Karlsson, Jan-Erik; Levin, Lars-Åke

2014-01-01

229

Correcting Four Similar Correlational Measures for Attenuation Due to Errors of Measurement in the Dependent Variable: Eta, Epsilon, Omega, and Intraclass r.  

ERIC Educational Resources Information Center

Besides the ubiquitous Pearson product-moment r, there are a number of other measures of relationship that are attenuated by errors of measurement and for which the relationship between true measures can be estimated. Among these are the correlation ratio (eta squared), Kelley's unbiased correlation ratio (epsilon squared), Hays' omega squared,…

Stanley, Julian C.; Livingston, Samuel A.

230

The Cross-Wavelet Transform and Analysis of Quasiperiodic Behavior in the Pearson-Readhead VLBI Survey Sources  

E-print Network

We introduce an algorithm for applying a cross-wavelet transform to analysis of quasiperiodic variations in a time-series, and introduce significance tests for the technique. We apply a continuous wavelet transform and the cross-wavelet algorithm to the Pearson-Readhead VLBI survey sources using data obtained from the University of Michigan 26-m parabloid at observing frequencies of 14.5, 8.0, and 4.8 GHz. Thirty of the sixty-two sources were chosen to have sufficient data for analysis, having at least 100 data points for a given time-series. Of these thirty sources, a little more than half exhibited evidence for quasiperiodic behavior in at least one observing frequency, with a mean characteristic period of 2.4 yr and standard deviation of 1.3 yr. We find that out of the thirty sources, there were about four time scales for every ten time series, and about half of those sources showing quasiperiodic behavior repeated the behavior in at least one other observing frequency.

Brandon C. Kelly; Philip A. Hughes; Hugh D. Aller; Margo F. Aller

2003-03-24

231

Discrete Pearson distributions  

SciTech Connect

These distributions are generated by a first order recursive scheme which equates the ratio of successive probabilities to the ratio of two corresponding quadratics. The use of a linearized form of this model will produce equations in the unknowns matched by an appropriate set of moments (assumed to exist). Given the moments we may find valid solutions. These are two cases; (1) distributions defined on the non-negative integers (finite or infinite) and (2) distributions defined on negative integers as well. For (1), given the first four moments, it is possible to set this up as equations of finite or infinite degree in the probability of a zero occurrence, the sth component being a product of s ratios of linear forms in this probability in general. For (2) the equation for the zero probability is purely linear but may involve slowly converging series; here a particular case is the discrete normal. Regions of validity are being studied. 11 refs.

Bowman, K.O. [Oak Ridge National Lab., TN (United States); Shenton, L.R. [Georgia Univ., Athens, GA (United States); Kastenbaum, M.A. [Kastenbaum (M.A.), Basye, VA (United States)

1991-11-01

232

Comparisons of two moments-based estimators that utilize historical and paleoflood data for the log Pearson type III distribution  

USGS Publications Warehouse

The expected moments algorithm (EMA) [Cohn et al., 1997] and the Bulletin 17B [Interagency Committee on Water Data, 1982] historical weighting procedure (B17H) for the log Pearson type III distribution are compared by Monte Carlo computer simulation for cases in which historical and/or paleoflood data are available. The relative performance of the estimators was explored for three cases: fixed-threshold exceedances, a fixed number of large floods, and floods generated from a different parent distribution. EMA can effectively incorporate four types of historical and paleoflood data: floods where the discharge is explicitly known, unknown discharges below a single threshold, floods with unknown discharge that exceed some level, and floods with discharges described in a range. The B17H estimator can utilize only the first two types of historical information. Including historical/paleoflood data in the simulation experiments significantly improved the quantile estimates in terms of mean square error and bias relative to using gage data alone. EMA performed significantly better than B17H in nearly all cases considered. B17H performed as well as EMA for estimating X100 in some limited fixed-threshold exceedance cases. EMA performed comparatively much better in other fixed-threshold situations, for the single large flood case, and in cases when estimating extreme floods equal to or greater than X500. B17H did not fully utilize historical information when the historical period exceeded 200 years. Robustness studies using GEV-simulated data confirmed that EMA performed better than B17H. Overall, EMA is preferred to B17H when historical and paleoflood data are available for flood frequency analysis.

England, J.F., Jr.; Salas, J.D.; Jarrett, R.D.

2003-01-01

233

Calculation of the threshold voltage of metal-oxide-semiconductor field-effect transistors with Pearson-IV channel doping profile  

Microsoft Academic Search

In this paper, a general analytical expression for the calculation of threshold voltage of an ion-implanted n-channel enhancement-mode metal-oxide-semiconductor field-effect transistor with a Pearson-IV channel dopant distribution is presented. Specifically, the threshold voltage in excess of the flat-band voltage is characterized as an explicit function of the four moments about the mean depth of the dopant distribution, namely, projected range,

D. L. Kwong; D. C. Meyers

1984-01-01

234

Does APO ?4 correlate with MRI changes in Alzheimer's disease?  

PubMed Central

OBJECTIVE—To assess the relation between APO E genotype and MRI white matter changes in Alzheimer's disease. The APO ?4 allele is correlated with amyloid angiopathy and other neuropathologies in Alzheimer's disease and could be associated with white matter changes. If so, there should be a dose effect.?METHODS—104 patients with probable Alzheimer's disease (NINCDS-ADRDA criteria) in this Alzheimer's Disease Research Centre were studied. Patients received MRI and APO E genotyping by standardised protocols. Axial MRI was scored (modified Schelten's scale) for the presence and degree of white matter changes and atrophy in several regions by a neuroradiologist blinded to genotype. Total white matter and total atrophy scores were also generated. Data analysis included Pearson's correlation for regional and total imaging scores and analysis of variance (ANOVA) (or Kruskal-Wallis) and ?2 for demographic and disease related variables.?RESULTS—30 patients had no ?4, 53 patients were heterozygous, and 21 patients were homozygous. The three groups did not differ in sex distribution, age of onset, age at MRI, MMSE, clinical dementia rating, or modified Hachinski ischaemia scores. There were no significant correlations between total or regional white matter scores and APO E genotype (Pearson correlation).?CONCLUSIONS—No correlation between total or regional white matter scores and APO E genotype was found. The pathogenesis of white matter changes in Alzheimer's disease may be independent of APO E genotype.?? PMID:11032626

Doody, R; Azher, S; Haykal, H; Dunn, J; Liao, T; Schneider, L

2000-01-01

235

Canonical correlation and chi-square: relationships and interpretation.  

PubMed

A 2 x 2 chi-square can be computed from a phi coefficient, which is the Pearson correlation between two binomial variables. Similarly, chi-square for larger contingency tables can be computed from canonical correlation coefficients. The authors address the following series of issues involving this relationship: (a) how to represent a contingency table in terms of a correlation matrix involving r - 1 row and c - 1 column dummy predictors; (b) how to compute chi-square from canonical correlations solved from this matrix; (c) how to compute loadings for the omitted row and column variables; and (d) the possible interpretive advantage of describing canonical relationships that comprise chi-square, together with some examples. The proposed procedures integrate chi-square analysis of contingency tables with general correlational theory and serve as an introduction to some recent methods of analysis more widely known by sociologists. PMID:11109997

Dunlap, W P; Brody, C J; Greer, T

2000-10-01

236

An analysis of factors correlated with the achievement of the goal standard for the science portion of the Connecticut Academic Performance Test  

NASA Astrophysics Data System (ADS)

This study sought to identify factors that could be used to predict the success of students on the science portion of the grade ten Connecticut Academic Performance Test (CAPT). While the Connecticut State Department of Education measures student achievement in mathematics, reading and writing in grades 4, 6, and 8, science is assessed only in the grade ten CAPT. Since the CAPT science test does not identify specific areas in need of improvement, it is not possible to determine causes for low test scores. To address this, the study investigated the predictive values of the grade eight Mastery Tests in mathematics and reading, the student ability scores of the Otis-Lennon School Ability Index, and grades in prior science courses. The research sample consisted of five hundred and twenty-five students, member of the graduating classes of 2000 and 2001 in a large suburban high school. Students in the study had participated in the district testing program and their scores for the grade seven Otis-Lennon School Ability Test (OLSAT), the grade eight Connecticut Mastery Tests (CMT) and the grade ten Connecticut Academic Performance Tests (CAPT) were available for analysis. This study investigated correlations between student achievement on the CMT and the science subtest of the CAPT, between OLSAT scores and the CAPT science scores, and between grades in ninth grade science and CAPT science scores. Scores were disaggregated by gender and by course level. Hypotheses 1, 2, 3 and 4 investigated the Pearson Product Moment Correlations of the OLSAT, CMT and course grades with scores on the science portion of the CAPT. Hypothesis 5 compared the scores of male and female students, using the t-test of independent sample means. Calculations showed moderate correlations for hypotheses 1--4, and the hypotheses were accepted. Hypothesis 5 was accepted for one class and rejected for the other. On the whole, female students received higher course grades and lower standardized test grades. Recommendations included the use of reading strategies to improve comprehension, the inclusion of inquiry-based science activities in the curriculum, and the development of valid and reliable classroom assessments that allow students to apply their content knowledge in authentic tasks. The suggestion that cultural and social factors could account for differences in scores of male and female students warrants further study.

Kmetz, Barbara Fotta

2001-07-01

237

Correlation of the NBME Advanced Clinical Examination in EM and the National EM M4 exams  

PubMed Central

Introduction Since 2011 two online, validated exams for fourth-year emergency medicine (EM) students have been available (National EM M4 Exams). In 2013 the National Board of Medical Examiners offered the Advanced Clinical Examination in Emergency Medicine (EM-ACE). All of these exams are now in widespread use; however, there are no data on how they correlate. This study evaluated the correlation between the EM-ACE exam and the National EM M4 Exams. Methods From May 2013 to April 2014 the EM-ACE and one version of the EM M4 exam were administered sequentially to fourth-year EM students at five U.S. medical schools. Data collected included institution, gross and scaled scores and version of the EM M4 exam. We performed Pearson’s correlation and random effects linear regression. Results 303 students took the EM-ACE and versions 1 (V1) or 2 (V2) of the EM M4 exams (279 and 24, respectively). The mean percent correct for the exams were as follows: EM-ACE 74.8 (SD-8.83), V1 83.0 (SD-6.41), V2 78.5 (SD-7.70). Pearson’s correlation coefficient for the V1/EM-ACE was 0.51 (0.42 scaled) and for the V2/EM-ACE was 0.59 (0.41 scaled). The coefficient of determination for V1/EM-ACE was 0.72 and for V2/EM-ACE = 0.71 (0.86 and 0.49 for scaled scores). The R-squared values were 0.25 and 0.30 (0.18 and 0.13, scaled), respectively. There was significant cluster effect by institution. Conclusion There was moderate positive correlation of student scores on the EM-ACE exam and the National EM M4 Exams. PMID:25671023

Hiller, Katherine; Miller, Emily S.; Lawson, Luan; Wald, David; Beeson, Michael; Heitz, Corey; Morrissey, Thomas; House, Joseph; Poznanski, Stacey

2015-01-01

238

Gene differential coexpression analysis based on biweight correlation and maximum clique  

PubMed Central

Differential coexpression analysis usually requires the definition of 'distance' or 'similarity' between measured datasets. Until now, the most common choice is Pearson correlation coefficient. However, Pearson correlation coefficient is sensitive to outliers. Biweight midcorrelation is considered to be a good alternative to Pearson correlation since it is more robust to outliers. In this paper, we introduce to use Biweight Midcorrelation to measure 'similarity' between gene expression profiles, and provide a new approach for gene differential coexpression analysis. Firstly, we calculate the biweight midcorrelation coefficients between all gene pairs. Then, we filter out non-informative correlation pairs using the 'half-thresholding' strategy and calculate the differential coexpression value of gene, The experimental results on simulated data show that the new approach performed better than three previously published differential coexpression analysis (DCEA) methods. Moreover, we use the maximum clique analysis to gene subset included genes identified by our approach and previously reported T2D-related genes, many additional discoveries can be found through our method. PMID:25474074

2014-01-01

239

Optical Correlation  

NASA Technical Reports Server (NTRS)

Pattern recognition may supplement or replace certain navigational aids on spacecraft in docking or landing activities. The need to correctly identify terrain features remains critical in preparation of autonomous planetary landing. One technique that may solve this problem is optical correlation. Correlation has been successfully demonstrated under ideal conditions; however, noise significantly affects the ability of the correlator to accurately identify input signals. Optical correlation in the presence of noise must be successfully demonstrated before this technology can be incorporated into system design. An optical correlator is designed and constructed using a modified 2f configuration. Liquid crystal televisions (LCTV) are used as the spatial light modulators (SLM) for both the input and filter devices. The filter LCTV is characterized and an operating curve is developed. Determination of this operating curve is critical for reduction of input noise. Correlation of live input with a programmable filter is demonstrated.

Cotariu, Steven S.

1991-01-01

240

Washington Correlator  

NASA Technical Reports Server (NTRS)

This report summarizes the activities of the Washington Correlator for 2012. The Washington Correlator provides up to 80 hours of attended processing per week plus up to 40 hours of unattended operation, primarily supporting Earth Orientation and astrometric observations. In 2012, the major programs supported include the IVS-R4, IVS-INT, APSG, and CRF observing sessions.

Hall, David M.; Boboltz, David

2013-01-01

241

Pairwise Correlations of Eight Strong DIBs and N(H), N(H2), and EBV  

Microsoft Academic Search

We discuss the correlations between equivalent widths of eight diffuse interstellar bands (DIBs), and examine their correlations with the column densities of atomic hydrogen (N(H)) and molecular hydrogen (N(H2)), and EB-V. The DIBs are centered at lambda 5780.5, 6204.5, 6283.8, 6196.0, 6613.6, 5705.1, 5797.1, and 5487.7, in decreasing order of Pearson's correlation coefficient with N(H), which ranges from 0.94 to

Scott D. Friedman; D. G. York; B. J. McCall; J. Dahlstrom; P. Sonnentrucker; D. E. Welty; M. M. Drosback; L. M. Hobbs; B. L. Rachford; T. P. Snow

2011-01-01

242

Correlation between Pediatric Balance Scale and Functional Test in Children with Cerebral Palsy  

PubMed Central

[Purpose] To investigate the correlation of functional balance with the functional performance of children with cerebral palsy. [Subjects and Methods] This was a cross-sectional study of children with cerebral palsy with mild to moderate impairment. The children were divided into 3 groups based on motor impairment. The evaluation consisted of the administration of the Pediatric Balance Scale (PBS) and the Pediatric Evaluation Disability Inventory. Correlations between the instruments were determined by calculating Pearson’s correlation coefficients. [Results] In Group 1, a strong positive correlation was found between the PBS and the mobility dimension of the Pediatric Evaluation Disability Inventory (r=0.82), and a moderate correlation was found between the PBS and self-care dimension of the Pediatric Evaluation Disability Inventory (r=0.51). In Group 2, moderate correlations were found between the PBS and both the self-care dimension (r=0.57) and mobility dimension (r=0.41) of the Pediatric Evaluation Disability Inventory. In Group 3, the PBS was weakly correlated with the self-care dimension (r=0.11) and moderately correlated with the mobility dimension (r=0.55). [Conclusion] The PBS proved to be a good auxiliary tool for the evaluation of functional performance with regard to mobility, but cannot be considered a predictor of function in children with cerebral palsy. PMID:25013281

Duarte, Natália de A. C.; Grecco, Luanda André Collange; Franco, Renata Calhes; Zanon, Nelci; Oliveira, Cláudia Santos

2014-01-01

243

Correlation of Radiographic Patellofemoral Indices with Tibial Tubercle Transfer Distance in Fulkerson Osteotomy Pl  

PubMed Central

Background A laterally tracking patella is commonly seen in patients with chronic recurrent lateral patellar dislocations. Clinical appearance of the J-sign occurs when the patella is congruent with the trochlear groove in flexion and moves over the lateral border of the femoral condyle as the lower leg reaches complete extension. A Fulkerson osteotomy procedure corrects this maltracking of the patella by medially transferring the tibial tubercle. There are many radiographic patellofemoral indices that can be used describe this incongruence about the patelloformal joint. The current literature supports the use of the tibial tubercle-trochlear groove (TT- TG) index in determining the appropriate amount medialization of the extensor mechanism. However there is little agreement in how far to transfer the tibial tubercle to best achieve maximum patello- femoral congruency. It is the senior author's belief that lateral patellar edge (LPE) measure on voluntary quadriceps active hyperextension MRI scan has the strongest correlation with final operative tibial tubercle transfer distance needed to achieve maximum patellofemoral congruency. Purpose The purpose of this study was to show that the voluntary quadriceps active hyperextension MRI measurement of lateral patellar edge (LPE) has the strongest correlation with tibial tubercle transfer distance required to achieve maxium patellofemoral congruency intraoperatively in the terminal 30 degrees of active knee extension compared to all other patellofemoral indices measured on axial MRI scans with the knee in voluntary active knee extension to 30 degrees of flexion, passive full extension, and voluntary quadriceps active hyperextension. Study Design Retrospective case series via review of the electronic medical record. Methods Forty-three Fulkerson osteotomy patient charts were reviewed retrospectively. Three different pre-operative axial MRI views were then examined and measured for Tibial Tubercle- Troch-lear Groove (tt-tg), lateral patellar edge (LPE), bisect offset (BSO), and lateral patellar displacement (LPD). Each patient had three MRIs: one with the knee resting in extension, one in voluntary quadriceps active hyperextension, and one in voluntary quadriceps active 30 degree flexion. Statistics were then calculated using Statistical Package for the Social Sciences (SPSS) (IBM corp). Results Tibial tubercle transfer distances required to achieve congruency intraoperatively correlated moderately (0.500-0.300) and were statistically significant (alpha. 050) for passive extension MRI measurement of TT-TG (Pearson- 0.403, alpha 0.010) and LPD (Pearson. 362, alpha 0.022); voluntary quadriceps active hyperextension TT-TG (Pearson 0.487, alpha, 0.001); voluntary quadriceps active flexion TT-TG (Pearson. 548, alpha< 0.001), LPE (Pearson. 332, alpha 0.029), and LPD (Pearson 0.446 alpha. 003). Conclusion The hypothesis that voluntary quadriceps active hyperextension MRI LPE measurement best correlated with tibial tubercle transfer distance was incorrect. The data collected showed correlation and statistical significance for voluntary quadriceps active flexion LPE with required tibal tubercle transfer distance (Pearson 0.34, alpha 0.026). The MRI measurement that best correlated with tibial tubercle transfer distance was voluntary quadriceps active flexion measure of TT-TG (Pearson. 556, alpha< 0.001). PMID:25328455

Edwards, Alan; Larson, Evan; Albright, John

2014-01-01

244

Gaussian graphical modeling reveals specific lipid correlations in glioblastoma cells  

NASA Astrophysics Data System (ADS)

Advances in high-throughput measurements of biological specimens necessitate the development of biologically driven computational techniques. To understand the molecular level of many human diseases, such as cancer, lipid quantifications have been shown to offer an excellent opportunity to reveal disease-specific regulations. The data analysis of the cell lipidome, however, remains a challenging task and cannot be accomplished solely based on intuitive reasoning. We have developed a method to identify a lipid correlation network which is entirely disease-specific. A powerful method to correlate experimentally measured lipid levels across the various samples is a Gaussian Graphical Model (GGM), which is based on partial correlation coefficients. In contrast to regular Pearson correlations, partial correlations aim to identify only direct correlations while eliminating indirect associations. Conventional GGM calculations on the entire dataset can, however, not provide information on whether a correlation is truly disease-specific with respect to the disease samples and not a correlation of control samples. Thus, we implemented a novel differential GGM approach unraveling only the disease-specific correlations, and applied it to the lipidome of immortal Glioblastoma tumor cells. A large set of lipid species were measured by mass spectrometry in order to evaluate lipid remodeling as a result to a combination of perturbation of cells inducing programmed cell death, while the other perturbations served solely as biological controls. With the differential GGM, we were able to reveal Glioblastoma-specific lipid correlations to advance biomedical research on novel gene therapies.

Mueller, Nikola S.; Krumsiek, Jan; Theis, Fabian J.; Böhm, Christian; Meyer-Bäse, Anke

2011-06-01

245

Pairwise Correlations Of Eight Strong DIBs And N(H), N(H2), And E(BV)  

Microsoft Academic Search

We establish correlations between equivalent widths of eight diffuse interstellar bands (DIBs), and examine their correlations with N(H), N(H2), and E(B-V). The DIBs are centered at 5780.5, 6204.5, 6283.8, 6196.0, 6613.6, 5705.1, 5797.1, and 5487.7, in decreasing order of Pearson's correlation coefficient with N(H), which range from 0.96 to 0.82. We find the equivalent width of 5780.5 is better correlated

Scott David Friedman; D. G. York; B. J. McCall; J. Dahlstrom; P. Sonnentrucker; D. E. Welty; M. M. Drosback; L. M. Hobbs; B. L. Rachford; T. P. Snow

2011-01-01

246

Memory effect and time correlations in breakdown initiation of DC glow discharge in argon and synthetic air  

NASA Astrophysics Data System (ADS)

The memory effect and correlations of the statistical and formative time delay in argon and synthetic air DC glow discharge at low pressure were studied. The memory coefficients and ratios and Pearson's and Spearman's correlation coefficients were determined, ranging from about unity at low relaxation times and vanishing at the saturation region of the memory curves (determined by the background ionization). It was shown that the statistical ts and the formative time delay tf are correlated variables and the positive correlation between them was confirmed experimentally and theoretically.

Markovi?, V. Lj.; Popovi?, B. ?.; Jovanovi?, A. P.; Stamenkovi?, S. N.; Stankov, M. N.

2015-01-01

247

Correlates of Frailty Among Homeless Adults  

PubMed Central

Frailty, a relatively unexplored concept among vulnerable populations, may be a significant issue for homeless adults. This cross-sectional study assessed correlates of frailty among middle age and older homeless adults (N = 150, 40–73). A Pearson (r) bivariate correlation revealed a weak relationship between frailty and being female (r = .230, p < .01). Significant moderate negative correlations were found between frailty and resilience (r = ?.395, p < .01), social support (r = ?.377, p < .01), and nutrition (r = ?.652, p < .01). Furthermore, Spearman’s rho (rs) bivariate correlations revealed a moderate positive relationship between frailty and health care utilization (rs = .444, p < .01). A stepwise backward linear regression analysis was conducted and in the final model, age, gender, health care utilization, nutrition, and resilience were significantly related to frailty. Over the next two decades, there is an anticipated increase in the number of homeless adults which will necessitate a greater understanding of the needs of this hard-to-reach population. PMID:23676627

Salem, Benissa E.; Nyamathi, Adeline M.; Brecht, Mary-Lynn; Phillips, Linda R.; Mentes, Janet C.; Sarkisian, Catherine; Leake, Barbara

2013-01-01

248

Correlates of frailty among homeless adults.  

PubMed

Frailty, a relatively unexplored concept among vulnerable populations, may be a significant issue for homeless adults. This cross-sectional study assessed correlates of frailty among middle age and older homeless adults (N = 150, 40-73). A Pearson (r) bivariate correlation revealed a weak relationship between frailty and being female (r = .230, p < .01). Significant moderate negative correlations were found between frailty and resilience (r = -.395, p < .01), social support (r = -.377, p < .01), and nutrition (r = -.652, p < .01). Furthermore, Spearman's rho (r s) bivariate correlations revealed a moderate positive relationship between frailty and health care utilization (r(s) = .444, p < .01). A stepwise backward linear regression analysis was conducted and in the final model, age, gender, health care utilization, nutrition, and resilience were significantly related to frailty. Over the next two decades, there is an anticipated increase in the number of homeless adults which will necessitate a greater understanding of the needs of this hard-to-reach population. PMID:23676627

Salem, Benissa E; Nyamathi, Adeline M; Brecht, Mary-Lynn; Phillips, Linda R; Mentes, Janet C; Sarkisian, Catherine; Leake, Barbara

2013-10-01

249

Applying Deeper Learning and Confucian Values in Enhancing School Effectiveness: Empirical Results and Findings  

ERIC Educational Resources Information Center

The study investigates how school teachers' personal background influences their deeper learning capacity and the school effectiveness. Furthermore, the study examines the correlation between teachers' learning capacity and school effectiveness. Four sets of analyses are performed: t tests, one-way ANOVAs, Pearson correlations, and stepwise…

Ho, Li-An; Lin, Chin-Yen; Kuo, Tsung-Hsien; Kuo, Yen-Ku; Kuo, Yen-Lin

2008-01-01

250

Estimating membrane voltage correlations from extracellular spike trains.  

PubMed

The cross-correlation coefficient between neural spike trains is a commonly used tool in the study of neural interactions. Two well-known complications that arise in its interpretation are 1) modulations in the correlation coefficient may result solely from changes in the mean firing rate of the cells and 2) the mean firing rates of the neurons impose upper and lower bounds on the correlation coefficient whose absolute values differ by an order of magnitude or more. Here, we propose a model-based approach to the interpretation of spike train correlations that circumvents these problems. The basic idea of our proposal is to estimate the cross-correlation coefficient between the membrane voltages of two cells from their extracellular spike trains and use the resulting value as the degree of correlation (or association) of neural activity. This is done in the context of a model that assumes the membrane voltages of the cells have a joint normal distribution and spikes are generated by a simple thresholding operation. We show that, under these assumptions, the estimation of the correlation coefficient between the membrane voltages reduces to the calculation of a tetrachoric correlation coefficient (a measure of association in nominal data introduced by Karl Pearson) on a contingency table calculated from the spike data. Simulations of conductance-based leaky integrate-and-fire neurons indicate that, despite its simplicity, the technique yields very good estimates of the intracellular membrane voltage correlation from the extracellular spike trains in biologically realistic models. PMID:12686584

Dorn, Jessy D; Ringach, Dario L

2003-04-01

251

Correlation between three color coordinates of human teeth  

NASA Astrophysics Data System (ADS)

The objective was to determine whether there were significant correlations in the three color coordinates within each of two color coordinate systems, such as the Commission Internationale de l'Eclairage (CIE) L*a*b* system, and the lightness, chroma, and hue angle system, of human vital teeth. The color of six maxillary and six mandibular anterior teeth was measured by the Shade Vision System. Pearson correlations between each pair of the color coordinates were determined (?=0.01). The influence of two color coordinates on the other color coordinate was determined with a multiple regression analysis (?=0.01). Based on correlation analyses, all the color coordinate pairs showed significant correlations except for the chroma and hue angle pair. The CIE L* was negatively correlated with the CIE a*, b*, and chroma, but positively correlated with the hue angle. The CIE a* was positively correlated with the CIE b* and chroma. Tooth color coordinates were correlated each other. Lighter teeth were less chromatic both in the CIE a* and b* coordinates. Therefore, it was postulated that the three color coordinates of human teeth were harmonized within certain color attribute ranges, and a lack of correlations in these coordinates might indicate external/internal discolorations and/or anomalies of teeth.

Lee, Yong-Keun

2014-11-01

252

An anthropometric study to evaluate the correlation between the occlusal vertical dimension and length of the thumb  

PubMed Central

Background Establishment of proper occlusal vertical dimension (OVD) is one of the important tasks for successful prosthodontic therapy. An ideal method for determining OVD in terms of cost, time, and instrument requirements has been sought in prosthodontics by various investigators. However, no such single method has been formulated. In the current anthropometric study, the relationship of the length of the thumb to the OVD was tested in two ethnic groups of Nepal, Aryans, and Mongoloids. The result of this study can be useful in determining proper OVD in edentulous patients. Aims and objectives The primary aim of the present study was to evaluate the correlation between the length of the thumb and OVD in Aryan and Mongoloid ethnic groups. The secondary aim was to compare the correlation between OVD and other anatomic measurements (eye–ear distance and pupil-to-rima oris distance) in these ethnicities. Materials and methods The OVD, thumb length, eye–ear distance and distance between pupil of eye and rima oris were measured in a total of 500 adult dentulous volunteers. The correlation between OVD and thumb length as well as other anatomic measurements was checked with Pearson’s product moment correlation coefficient. Linear regression analysis was performed to determine the relationship of OVD to the length of the thumb. Results The thumb length was significantly (P?0.05) correlated with strong and positive values (Pearson’s coefficient =0.874 in the whole population, 0.826 in Aryans, and 0.944 in Mongoloids). Regression analysis showed that thumb length was significantly related to OVD in both ethnic groups. Conclusion Within the limitations of the present study, the result implies that thumb length can be used as an adjunct for establishing OVD in the edentulous patients. PMID:25678817

Basnet, Bishal Babu; Parajuli, Prakash Kumar; Singh, Raj Kumar; Suwal, Pramita; Shrestha, Pragya; Baral, Dharanidhar

2015-01-01

253

Correlations between blood glucose and breath components from portable gas sensors and PTR-TOF-MS.  

PubMed

Acetone is one of the most abundant volatile compounds in the human breath and might be important for monitoring diabetic patients. Here, a portable acetone sensor consisting of flame-made, nanostructured, Si-doped WO3 sensing films was used to analyse the end tidal fraction of the breath (collected in Tedlar bags) from eight healthy volunteers after overnight fasting (morning) and after lunch (afternoon). After breath sampling, the gaseous components were also analysed by proton transfer reaction time-of-flight mass spectrometry (PTR-TOF-MS), and each person's blood glucose level was measured. The portable sensor accurately detected the presence of acetone with fast response/recovery times (<12 s) and a high signal-to-noise ratio. Statistical analysis of the relationship between the PTR-TOF-MS measurements of breath gases (e.g., acetone, isoprene, ethanol and methanol), sensor response and the blood glucose level was performed for both sampling periods. The best correlations were found after overnight fasting (morning): in particular, between blood glucose level and breath acetone (Pearson's 0.98 and Spearman's 0.93). Whereas the portable sensor response correlated best with the blood glucose (Pearson's 0.96 and Spearman's 0.81) and breath acetone (Pearson's 0.92 and Spearman's 0.69). PMID:23959908

Righettoni, M; Schmid, A; Amann, A; Pratsinis, S E

2013-09-01

254

Correlative Tomography  

PubMed Central

Increasingly researchers are looking to bring together perspectives across multiple scales, or to combine insights from different techniques, for the same region of interest. To this end, correlative microscopy has already yielded substantial new insights in two dimensions (2D). Here we develop correlative tomography where the correlative task is somewhat more challenging because the volume of interest is typically hidden beneath the sample surface. We have threaded together x-ray computed tomography, serial section FIB-SEM tomography, electron backscatter diffraction and finally TEM elemental analysis all for the same 3D region. This has allowed observation of the competition between pitting corrosion and intergranular corrosion at multiple scales revealing the structural hierarchy, crystallography and chemistry of veiled corrosion pits in stainless steel. With automated correlative workflows and co-visualization of the multi-scale or multi-modal datasets the technique promises to provide insights across biological, geological and materials science that are impossible using either individual or multiple uncorrelated techniques. PMID:24736640

Burnett, T. L.; McDonald, S. A.; Gholinia, A.; Geurts, R.; Janus, M.; Slater, T.; Haigh, S. J.; Ornek, C.; Almuaili, F.; Engelberg, D. L.; Thompson, G. E.; Withers, P. J.

2014-01-01

255

Correlation Correlogram  

E-print Network

Network Correlation Neural Oscillator Correlogram CrossHair cell Cochlear Filtering Signal oscillator is combination of raw input (Ir - based on segments), global inhibition and network activity oscillators is active, all others are suppressed; i.e. only one group can be active at any one time. Io Ir Wz

Wrigley, Stuart

256

Correlation spectrometer  

DOEpatents

A correlation spectrometer can detect a large number of gaseous compounds, or chemical species, with a species-specific mask wheel. In this mode, the spectrometer is optimized for the direct measurement of individual target compounds. Additionally, the spectrometer can measure the transmission spectrum from a given sample of gas. In this mode, infrared light is passed through a gas sample and the infrared transmission signature of the gasses present is recorded and measured using Hadamard encoding techniques. The spectrometer can detect the transmission or emission spectra in any system where multiple species are present in a generally known volume.

Sinclair, Michael B. (Albuquerque, NM); Pfeifer, Kent B. (Los Lunas, NM); Flemming, Jeb H. (Albuquerque, NM); Jones, Gary D. (Tijeras, NM); Tigges, Chris P. (Albuquerque, NM)

2010-04-13

257

Closure and ratio correlation analysis of lunar chemical and grain size data  

NASA Technical Reports Server (NTRS)

Major element and major element plus trace element analyses were selected from the lunar data base for Apollo 11, 12 and 15 basalt and regolith samples. Summary statistics for each of the six data sets were compiled, and the effects of closure on the Pearson product moment correlation coefficient were investigated using the Chayes and Kruskal approximation procedure. In general, there are two types of closure effects evident in these data sets: negative correlations of intermediate size which are solely the result of closure, and correlations of small absolute value which depart significantly from their expected closure correlations which are of intermediate size. It is shown that a positive closure correlation will arise only when the product of the coefficients of variation is very small (less than 0.01 for most data sets) and, in general, trace elements in the lunar data sets exhibit relatively large coefficients of variation.

Butler, J. C.

1976-01-01

258

The correlated network of acupuncture effect: a functional connectivity study.  

PubMed

A functional connectivity, which are temporally correlated in functionally related brain regions, before and after acupuncture manipulation was measured by MRI. Amygdala, as the control system of endogenetic analgesia, was selected for "seed" point. We found that compelling similarity existed in the network of resting state before and after acupuncture manipulation. A paired student t-test was implemented to investigate under the different conditions. The main difference was found in the limbic system, brainstem and cerebellum. We conclude that the default endogenous analgesia functional network exists in human brain at a low level, and it could be increased to a higher level by acupuncture modulation. PMID:17946400

Qin, Wei; Tian, Jie; Pan, Xiaohong; Yang, Lin; Zhen, Zonglei

2006-01-01

259

LUTEINIZING HORMONE CORRELATES WITH ADRENAL FUNCTION IN POSTMENOPAUSAL WOMEN  

PubMed Central

Objective In postmenopausal women, a relationship between luteinizing hormone (LH) and cortisol levels has been suggested. Furthermore, LH receptors on the adrenal gland have been shown to mediate ACTH-independent Cushing's Syndrome. In contrast, follicle stimulating hormone (FSH) receptors have not been found on the adrenal gland. Our objective was to explore the relationship of LH with adrenal function in postmenopausal women, as assessed by 24-hour urinary free cortisol (UFC) and aldosterone excretion rate (AER). Methods Participants were studied at single time point in the fasting state in the Clinical Research Center of Brigham and Women's Hospital. We studied 36 postmenopausal women in sodium balance to control for variation in endogenous levels of plasma renin activity and angiotensin II. Serum cortisol, aldosterone, LH and FSH levels were measured, as were 24-hour UFC and AER. Correlations were performed by calculation of Pearson's correlation coefficient. Results Serum LH correlated significantly with log-transformed UFC (r = 0.43, p=0.01) and inversely with log AER (r = ?0.50, p= 0.002). We found no correlation of serum LH with serum cortisol or aldosterone, nor did we find correlation of FSH with these parameters. Conclusions In postmenopausal women, serum LH levels correlate significantly with UFC (positively) and AER (negatively). LH stimulation may induce subtle shifts in adrenal function towards cortisol secretion. PMID:22713862

Saxena, Aditi R.; Seely, Ellen W.

2012-01-01

260

Substance Abuse Counselors and Moral Reasoning: Hypothetical and Authentic Dilemmas  

ERIC Educational Resources Information Center

This exploratory study examined the assumption that the level of moral reasoning (Defining Issues Test; J. R. Rest, 1986) used in solving hypothetical and authentic dilemmas is similar for substance abuse counselors (N = 188). The statistical analyses used were paired-sample t tests, Pearson product-moment correlation, and simultaneous multiple…

Sias, Shari M.

2009-01-01

261

Are the Best Higher Education Journals Really the Best? A Meta-Analysis of Writing Quality and Readability.  

ERIC Educational Resources Information Center

This study examined the relationship between writing quality, readability, and selectivity in 17 higher education journals. Readability was assessed through two indexes of readability. Data were analyzed using zero-order Pearson product-moment correlations, independent two sample t-tests, and analysis of covariance. Findings show that quality of…

Shelley, Mack C., II; Schuh, John H.

262

Information and Communication Technology (ICT) Usage and Achievement of Turkish Students in Pisa 2006  

ERIC Educational Resources Information Center

The purpose of this study is to examine the ICT usage and academic achievement of Turkish students in PISA 2006 data. The sample of the study included 4942 students from 160 schools. Frequencies, independent samples t-tests, ANOVAs, pearson correlation coefficients, exploratory factor analysis, and regression analysis were used. A high percentage…

Aypay, Ahmet

2010-01-01

263

Ninth and Tenth Grade Students' Mathematics Self-Efficacy Beliefs: The Sources and Relationships to Teacher Classroom Interpersonal Behaviors  

ERIC Educational Resources Information Center

The purpose of the mix-methods action research study was to seek how the changes in students' perceptions about teacher classroom interpersonal behaviors, the four efficacy sources and mathematics self-efficacy beliefs were related. The methods used to accomplish this were: descriptive statistics, t-test, Pearson correlation coefficient…

White, Amanda Garrett

2009-01-01

264

Type II Robustness of H0: Rho=0 for Non-Normal Distributions  

ERIC Educational Resources Information Center

Is the t test statistic for the Pearson Product Moment Correlation Coefficient robust to errors of the second kind? This investigation indirectly measured the effects of power through a type 2 error rate robustness study. The results were revealing. [The dissertation citations contained here are published with the permission of ProQuest LLC.…

Wren, Stephanie D.

2010-01-01

265

Inferring correlation networks from genomic survey data.  

PubMed

High-throughput sequencing based techniques, such as 16S rRNA gene profiling, have the potential to elucidate the complex inner workings of natural microbial communities - be they from the world's oceans or the human gut. A key step in exploring such data is the identification of dependencies between members of these communities, which is commonly achieved by correlation analysis. However, it has been known since the days of Karl Pearson that the analysis of the type of data generated by such techniques (referred to as compositional data) can produce unreliable results since the observed data take the form of relative fractions of genes or species, rather than their absolute abundances. Using simulated and real data from the Human Microbiome Project, we show that such compositional effects can be widespread and severe: in some real data sets many of the correlations among taxa can be artifactual, and true correlations may even appear with opposite sign. Additionally, we show that community diversity is the key factor that modulates the acuteness of such compositional effects, and develop a new approach, called SparCC (available at https://bitbucket.org/yonatanf/sparcc), which is capable of estimating correlation values from compositional data. To illustrate a potential application of SparCC, we infer a rich ecological network connecting hundreds of interacting species across 18 sites on the human body. Using the SparCC network as a reference, we estimated that the standard approach yields 3 spurious species-species interactions for each true interaction and misses 60% of the true interactions in the human microbiome data, and, as predicted, most of the erroneous links are found in the samples with the lowest diversity. PMID:23028285

Friedman, Jonathan; Alm, Eric J

2012-01-01

266

Correlation between the pressure-to-cornea index and both structural and functional measures of glaucoma  

PubMed Central

Purpose: the pressure-to-cornea index (PCI) was proposed in order to integrate intraocular pressure and central cornea thickness as a single-risk factor for glaucoma. The purpose of this study was to correlate the PCI with a structural and two functional measures of glaucoma. Setting: University Hospital in South America. Materials and Methods: Pressure-to-cornea index was calculated for 70 eyes of 36 subjects (glaucoma and suspects). Cup-to-disc (C/D) ratio, mean deviation (MD) and pattern standard deviation (PSD) as recorded by Humphrey automated perimetry (SITA 24-2) were correlated with PCI (Pearson's correlation coefficient). Results: Pearson's correlation coefficient between PCI and C/D was 0.329 (95% confidence interval [95% CI], 0.09–0.526; P = 0.006); between PCI and MD was ? 0.356 MD (95% CI, ?0.549 to ? 0.126; P = 0.003); and between PCI and PSD was ? 0.215 (95% CI, ?0.433 to 0.025; P = 0.07). Conclusion: In addition to serve as a single-risk factor, PCI can be used to stage glaucoma severity as well. PMID:25370390

Franco, Andrea M B V; Kasahara, Niro

2014-01-01

267

Measurement of carotid artery stenosis: correlation analysis between B-mode ultrasonography and contrast arteriography  

PubMed Central

Purpose To evaluate the efficacy of B-mode ultrasonography (US) in measurement of carotid stenosis% (CS%). Methods One hundred and thirth-three carotid arteries in 96 patients who underwent both carotid US and carotid arteriography (CA) were included in this retrospective study. To measure CS% on US, a cross sectional view of the most stenotic segment of the internal carotid artery was captured and residual diameter and original diameter of that segment were measured with electronic caliper on the same plane and in the same direction. To measure CS% on an angiogram, we used European Carotid Surgery Trial (ECST) and the North American Symptomatic Carotid Endarterectomy Trial (NASCET) methods. Pearson's correlation analysis and linear regression analysis were used to determine the correlation between CS% on an US and angiogram. Results Pearson's correlation coefficient (R) between CS% measured in US and CA were 0.853 (ECST method, P < 0.001) and 0.828 (NASCET method, P < 0.001). Accuracies of B-mode US were 93.2%, 88.0%, and 81.2% for estimating CS% by ECST method and 86.5%, 82.7%, and 82% for estimating CS% by NASCET method. Conclusion CS% measured in B-mode US was simpler and showed a strong positive correlation with that measured on an arteriogram either ECST or NASCET method. PMID:22066059

Lee, Kyo Won; Park, Yang Jin; Rho, Young-Nam; Kim, Dong-Ik

2011-01-01

268

THOMAS W. PEARSON Curriculum Vitae  

E-print Network

University of New York at Binghamton, 2009 MA, Anthropology, State University of New York at Binghamton the Hydrocarbon Commodity Chain: Frac-Sand Mining in Wisconsin. "The Implications of Hydraulic Fracturing

Wu, Mingshen

269

Correlation between ocular perfusion pressure fluctuation and glaucoma severity.  

PubMed

The aim of the study is to assess the correlation between ocular perfusion pressure (OPP) fluctuation and the severity of glaucoma. Forty-three patients with primary open-angle glaucoma (POAG) were enrolled in the study. All subjects had intraocular pressure (IOP) and blood pressure measured at three time points (7:00 a.m., 1:00 p.m. and 7:00 p.m.). OPP was calculated based upon blood pressure and IOP, and OPP fluctuation was calculated as the standard deviation of the three measurements. OPP fluctuation was correlated with a structural measure (cup-to-disk ratio) and two functional measures [mean deviation (MD) and pattern standard deviation (PSD) values from automated perimetry] with the Pearson's correlation coefficient. OPP fluctuation showed statistically significant correlation with both MD (r = -0.35, P = 0.01) and PDS (r = 0.44, P = 0.00). No correlation was found between OPP fluctuation and cup-to-disk ratio (r = 0.10, P = 0.48). POAG patients with higher OPP fluctuation have greater severity of disease as measured by functional parameters. PMID:24643517

de Oliveira, Ana Paula Chaves; Kasahara, Niro

2015-04-01

270

Pearson-Readhead Survey Sources II: The Longterm Centimeter-band Total Flux and Linear Polarization Properties of a Complete Radio Sample  

E-print Network

Using UMRAO centimeter-band total flux density and linear polarization monitoring observations of the complete Pearson-Readhead extragalactic source sample obtained between August 1984 and March 2001, we identify the range of variability in extragalactic objects as functions of optical and radio morphological classification, and relate total flux density variations to structural changes in published coeval VLBI maps in selected objects. We have identified preferred orientations of the electric vector of the polarized emission at 14.5 and 4.8 GHz in roughly half of the objects, and compared these with orientations of the flow direction indicated by VLBI morphology. When comparing the distributions of the orientation offsets for the BL Lacs and for the QSOs, we find differences in both range and mean value, in support of intrinsic class differences. In the shock-in-jet scenario, we attribute this to the allowed range of obliquities of shocks developing in the flow relative to the flow direction. The fact that we find longterm stability in EVPA over many events implies that a dominant magnetic field orientation persists; in the core-dominated objects, with small contribution from the underlying quiescent jet, this plausibly suggests that the magnetic field has a longterm memory, with subsequent shock events exhibiting similar EVPA orientation, or, alternatively, the presence of a standing shock in the core. We have looked for systematic, monotonic changes in EVPA which might be expected in the emission from a precessing jet, a model currently invoked for some AGNs; none were identified. Further, we carried out a Scargle periodogram analysis of the total flux density observations, but found no strong evidence for periodicity in any of the sample sources.

M. F. Aller; H. D. Aller; P. A. Hughes

2002-11-12

271

BDNF promoter I methylation correlates between post-mortem human peripheral and brain tissues.  

PubMed

Several psychiatric disorders have been associated with CpG methylation changes in CG rich promoters of the brain-derived neurotrophic factor (BDNF) mainly by extracting DNA from peripheral blood cells. Whether changes in peripheral DNA methylation can be used as a proxy for brain-specific alterations remains an open question. In this study we aimed to compare DNA methylation levels in BDNF promoter regions in human blood cells, muscle and brain regions using bisulfite-pyrosequencing. We found a significant correlation between the levels of BDNF promoter I methylation measured in quadriceps and vPFC tissues extracted from the same individuals (n=98, Pearson, r=0.48, p=4.5×10(-7)). In the hippocampus, BDNF promoter I and IV methylation levels were strongly correlated (Pearson, n=37, r=0.74, p=1.4×10(-7)). We found evidence for sex-dependent effect on BDNF promoter methylation levels in the various tissues and blood samples. Taken together, these data indicate a strong intra-individual correlation between peripheral and brain tissue. They also suggest that sex determines methylation patterns in BDNF promoter region across different types of tissue, including muscle, brain, and blood. PMID:25450314

Stenz, Ludwig; Zewdie, Seblewongel; Laforge-Escarra, Térèse; Prados, Julien; La Harpe, Romano; Dayer, Alexandre; Paoloni-Giacobino, Ariane; Perroud, Nader; Aubry, Jean-Michel

2015-02-01

272

Correlation of zinc with oxidative stress biomarkers.  

PubMed

Hypertension and smoking are related with oxidative stress (OS), which in turn reports on cellular aging. Zinc is an essential element involved in an individual's physiology. The aim of this study was to evaluate the relation of zinc levels in serum and urine with OS and cellular aging and its effect on the development of hypertension. In a Spanish sample with 1500 individuals, subjects aged 20-59 years were selected, whose zinc intake levels fell within the recommended limits. These individuals were classified according to their smoking habits and hypertensive condition. A positive correlation was found (Pearson's C = 0.639; p = 0.01) between Zn serum/urine quotient and oxidized glutathione levels (GSSG). Finally, risk of hypertension significantly increased when the GSSG levels exceeded the 75 percentile; OR = 2.80 (95%CI = 1.09-7.18) and AOR = 3.06 (95%CI = 0.96-9.71). Low zinc levels in serum were related with OS and cellular aging and were, in turn, to be a risk factor for hypertension. PMID:25774936

Morales-Suárez-Varela, María; Llopis-González, Agustín; González-Albert, Verónica; López-Izquierdo, Raúl; González-Manzano, Isabel; Cháves, Javier; Huerta-Biosca, Vicente; Martin-Escudero, Juan C

2015-01-01

273

Spatial correlation structure of monthly rainfall at a mesoscale region of north-eastern Bohemia  

NASA Astrophysics Data System (ADS)

The spatial correlation structure of monthly rainfall was analysed using data from 38 rain gauges located in north-eastern Bohemia. Three different inter-station correlation measures—Pearson's correlation coefficient, Spearman's rank-order correlation coefficient and Kendall's tau rank correlation coefficient—were estimated using monthly rainfall records from a recent 31-year period. Six different theoretical parametric correlation models were identified using the nonlinear least squares method. The spatial correlation structure was described using the fitted parameters. Comparison of estimated correlation models showed that, as measured by standard error, the best fitted was a two-parameter exponential model. The relationships between parameters of the exponential two-parameter model were further explored and described. The temporal variability of correlation showed trends in the fitted parameters over the studied period. On a seasonal basis, the correlation between the stations was stronger in autumn and winter than in spring and summer. The spatial variability of estimated parameters revealed that parameters of Matérn and two-parameter exponential models were dependent on altitude.

Svoboda, Vojt?ch; Máca, Petr; Hanel, Martin; Pech, Pavel

2014-08-01

274

Correlation between centrality metrics and their application to the opinion model  

NASA Astrophysics Data System (ADS)

In recent decades, a number of centrality metrics describing network properties of nodes have been proposed to rank the importance of nodes. In order to understand the correlations between centrality metrics and to approximate a high-complexity centrality metric by a strongly correlated low-complexity metric, we first study the correlation between centrality metrics in terms of their Pearson correlation coefficient and their similarity in ranking of nodes. In addition to considering the widely used centrality metrics, we introduce a new centrality measure, the degree mass. The mth-order degree mass of a node is the sum of the weighted degree of the node and its neighbors no further than m hops away. We find that the betweenness, the closeness, and the components of the principal eigenvector of the adjacency matrix are strongly correlated with the degree, the 1st-order degree mass and the 2nd-order degree mass, respectively, in both network models and real-world networks. We then theoretically prove that the Pearson correlation coefficient between the principal eigenvector and the 2nd-order degree mass is larger than that between the principal eigenvector and a lower order degree mass. Finally, we investigate the effect of the inflexible contrarians selected based on different centrality metrics in helping one opinion to compete with another in the inflexible contrarian opinion (ICO) model. Interestingly, we find that selecting the inflexible contrarians based on the leverage, the betweenness, or the degree is more effective in opinion-competition than using other centrality metrics in all types of networks. This observation is supported by our previous observations, i.e., that there is a strong linear correlation between the degree and the betweenness, as well as a high centrality similarity between the leverage and the degree.

Li, Cong; Li, Qian; Van Mieghem, Piet; Stanley, H. Eugene; Wang, Huijuan

2015-03-01

275

Correlation Between University Students' Kinematic Achievement and Learning Styles  

NASA Astrophysics Data System (ADS)

In the literature, some researches on kinematics revealed that students have many difficulties in connecting graphs and physics. Also some researches showed that the method used in classroom affects students' further learning. In this study the correlation between university students' kinematics achieve and learning style are investigated. In this purpose Kinematics Achievement Test and Learning Style Inventory were applied to 573 students enrolled in general physics 1 courses at Balikesir University in the fall semester of 2005-2006. Kinematics Test, consists of 12 multiple choose and 6 open ended questions, was developed by researchers to assess students' understanding, interpreting, and drawing graphs. Learning Style Inventory, a 24 items test including visual, auditory, and kinesthetic learning styles, was developed and used by Barsch. The data obtained from in this study were analyzed necessary statistical calculations (T-test, correlation, ANOVA, etc.) by using SPSS statistical program. Based on the research findings, the tentative recommendations are made.

Çirkino?lu, A. G.; Dem&ircidot, N.

2007-04-01

276

Diversity of the Vaginal Microbiome Correlates With Preterm Birth  

PubMed Central

Reproductive tract infection is a major initiator of preterm birth (PTB). The objective of this prospective cohort study of 88 participants was to determine whether PTB correlates with the vaginal microbiome during pregnancy. Total DNA was purified from posterior vaginal fornix swabs during gestation. The 16S ribosomal RNA gene was amplified using polymerase chain reaction primers, followed by chain-termination sequencing. Bacteria were identified by comparing contig consensus sequences with the Ribosomal Database Project. Dichotomous responses were summarized via proportions and continuous variables via means ± standard deviation. Mean Shannon Diversity index differed by Welch t test (P = .00016) between caucasians with PTB and term gestation. Species diversity was greatest among African Americans (P = .0045). Change in microbiome/Lactobacillus content and presence of putative novel/noxious bacteria did not correlate with PTB. We conclude that uncultured vaginal bacteria play an important role in PTB and race/ethnicity and sampling location are important determinants of the vaginal microbiome. PMID:23715799

Hyman, Richard W.; Fukushima, Marilyn; Jiang, Hui; Fung, Eula; Rand, Larry; Johnson, Brittni; Vo, Kim Chi; Caughey, Aaron B.; Hilton, Joan F.; Davis, Ronald W.; Giudice, Linda C.

2014-01-01

277

YKL-40 in Asthma and its correlation with different clinical parameters.  

PubMed

It has been suggested that elevated serum level of YKL-40 could be a marker for asthma and its severity. Along with few published studies, we investigated its correlation with asthma and its severity as well as spirometric indices.114 patients with asthma and 114 healthy controls underwent the assessment of serum level of YKL-40 (by ELISA) and spirometric indices. Pearson's coefficient determined the correlation between the variables and multivariate linear regression analysis was used for adjusting the effect of different probable confounding factors.Serum levels of YKL-40 were significantly higher in the asthmatic patients compared to those in healthy people (p<0.001). We also found a significant correlation between YKL-40 serum level and spirometric indices even after adjusting the effects of other variables.We report for the first time in an Iranian population that YKL-40 may be a good diagnostic marker of asthma in serum. PMID:24659163

Saba, Mohammadali; Sharif, Mohammad Reza; Akbari, Hossein; Nikoueinejad, Hassan; Ramazani Jolfaii, Maryam

2014-08-01

278

Mucocutaneous Manifestations of HIV and the Correlation with WHO Clinical Staging in a Tertiary Hospital in Nigeria  

PubMed Central

Skin diseases are indicators of HIV/AIDS which correlates with WHO clinical stages. In resource limited environment where CD4 count is not readily available, they can be used in assessing HIV patients. The study aims to determine the mucocutaneous manifestations in HIV positive patients and their correlation with WHO clinical stages. A prospective cross-sectional study of mucocutaneous conditions was done among 215 newly diagnosed HIV patients from June 2008 to May 2012 at adult ART clinic, Wesley Guild Hospital Unit, OAU Teaching Hospitals Complex, Ilesha, Osun State, Nigeria. There were 156 dermatoses with oral/oesophageal/vaginal candidiasis (41.1%), PPE (24.4%), dermatophytic infections (8.9%), and herpes zoster (3.8%) as the most common dermatoses. The proportions of dermatoses were 4.5%, 21.8%, 53.2%, and 20.5% in stages 1–4, respectively. A significant relationship (using Pearson's Chi square with P value <0.05) was obtained between dermatoses and WHO clinical stages. Pearson's correlation coefficient showed a positive correlation between the number of dermatoses and the WHO clinical stages. Dermatoses can therefore serve as diagnostic and prognostic markers in resource limited settings to initiate HAART in clinical stages 3 and 4. PMID:25587439

Oninla, Olumayowa Abimbola

2014-01-01

279

The correlates of body mass index and risk factors for being overweight among preschoolers with motor delay.  

PubMed

This cross-sectional study investigated the correlates of body mass index (BMI) and risk factors for overweight among 91 children with motor delay (MD) aged 9-73 months. Anthropometric measurements and questionnaires regarding multiple risk factors were obtained. Simple correlations between BMI percentile classifications and potential predictors were examined using Spearman's rank/Pearson's correlations and ?2 analysis. Multiple predictors of overweight were analyzed using logistic regression. BMI was correlated positively with higher caloric intake (rs = .21, p < .05) and negatively with passive activity (rs = ?.21, p < .05). When multiple predictors were considered, more severe dysphagia (odds ratio [OR], 2.81, p = .027, 95% confidence interval [CI], 1.13-7.03) and antiepileptic drug use (OR, 19.11, p = .008, 95% CI, 2.14-170.81) had significant partial effects on overweight status. Agencies supporting early development should consider caregiver education regarding the potential implication of feeding style and medication on BMI. PMID:24762387

Hwang, Ai-Wen; Wu, I-Chin; Chen, Chiao-Nan; Cheng, Hsin-Yi Kathy; Chen, Chia-Ling

2014-04-01

280

Is there an optimal substitution matrix for contact prediction with correlated mutations?  

PubMed

Correlated mutations in proteins are believed to occur in order to preserve the protein functional folding through evolution. Their values can be deduced from sequence and/or structural alignments and are indicative of residue contacts in the protein three-dimensional structure. A correlation among pairs of residues is routinely evaluated with the Pearson correlation coefficient and the MCLACHLAN similarity matrix. In literature, there is no justification for the adoption of the MCLACHLAN instead of other substitution matrices. In this paper, we approach the problem of computing the optimal similarity matrix for contact prediction with correlated mutations, i.e., the similarity matrix that maximizes the accuracy of contact prediction with correlated mutations. We describe an optimization procedure, based on the gradient descent method, for computing the optimal similarity matrix and perform an extensive number of experimental tests. Our tests show that there is a large number of optimal matrices that perform similarly to MCLACHLAN. We also obtain that the upper limit to the accuracy achievable in protein contact prediction is independent of the optimized similarity matrix. This suggests that the poor scoring of the correlated mutations approach may be due to the choice of the linear correlation function in evaluating correlated mutations. PMID:20855922

Di Lena, Pietro; Fariselli, Piero; Margara, Luciano; Vassura, Marco; Casadio, Rita

2011-01-01

281

Late Holocene earthquake history of the Brigham City segment of the Wasatch fault zone at the Hansen Canyon, Kotter Canyon, and Pearsons Canyon trench sites, Box Elder County, Utah  

USGS Publications Warehouse

Of the five central segments of the Wasatch fault zone (WFZ) having evidence of recurrent Holocene surface-faulting earthquakes, the Brigham City segment (BCS) has the longest elapsed time since its most recent surface-faulting event (~2.1 kyr) compared to its mean recurrence time between events (~1.3 kyr). Thus, the BCS has the highest time-dependent earthquake probability of the central WFZ. We excavated trenches at three sites––the Kotter Canyon and Hansen Canyon sites on the north-central BCS and Pearsons Canyon site on the southern BCS––to determine whether a surface-faulting earthquake younger than 2.1 ka occurred on the BCS. Paleoseismic data for Hansen Canyon and Kotter Canyon confirm that the youngest earthquake on the north-central BCS occurred before 2 ka, consistent with previous north-central BCS investigations at Bowden Canyon and Box Elder Canyon. At Hansen Canyon, the most recent earthquake is constrained to 2.1–4.2 ka and had 0.6–2.5 m of vertical displacement. At Kotter Canyon, we found evidence for two events at 2.5 ± 0.3 ka and 3.5 ± 0.3 ka, with an average displacement per event of 1.9–2.3 m. Paleoseismic data from Pearsons Canyon, on the previously unstudied southern BCS, indicate that a post-2 ka earthquake ruptured this part of the segment. The Pearsons Canyon earthquake occurred at 1.2 ± 0.04 ka and had 0.1–0.8 m of vertical displacement, consistent with our observation of continuous, youthful scarps on the southern 9 km of the BCS having 1–2 m of late Holocene(?) surface offset. The 1.2-ka earthquake on the southern BCS likely represents rupture across the Weber–Brigham City segment boundary from the penultimate Weber-segment earthquake at about 1.1 ka. The Pearsons Canyon data result in a revised length of the BCS that has not ruptured since 2 ka (with time-dependent probability implications), and provide compelling evidence of at least one segment-boundary failure and multi-segment rupture on the central WFZ. Our paleoseismic investigations of the BCS clarify the timing, displacement, and extent of late Holocene earthquakes on the segment, and importantly, confirm the long elapsed time since the most recent earthquake on most of the BCS.

DuRoss, Christopher B.; Personius, Stephen F.; Crone, Anthony J.; McDonald, Greg N.; Briggs, Richard W.

2012-01-01

282

Photon correlation holography.  

PubMed

Unconventional holography called photon correlation holography is proposed and experimentally demonstrated. Using photon correlation, i.e. intensity correlation or fourth order correlation of optical field, a 3-D image of the object recorded in a hologram is reconstructed stochastically with illumination through a random phase screen. Two different schemes for realizing photon correlation holography are examined by numerical simulations, and the experiment was performed for one of the reconstruction schemes suitable for the experimental proof of the principle. The technique of photon correlation holography provides a new insight into how the information is embedded in the spatial as well as temporal correlation of photons in the stochastic pseudo thermal light. PMID:21263682

Naik, Dinesh N; Singh, Rakesh Kumar; Ezawa, Takahiro; Miyamoto, Yoko; Takeda, Mitsuo

2011-01-17

283

Correlates of loneliness among university students  

PubMed Central

Background The purpose of this study was to investigate level of loneliness, essential needs during university education, and relationships between loneliness, essential needs, and characteristics of university students. A sample comprising 721 students participated in the study. The mean age was 21.58 (SD = 1.73) with a range from 18 to 25. The majority of the students were female (70.6%) and were living in students' dormitory (67.5%) with low (87.8%) income, away from their parents. Methods The UCLA-R loneliness scale and sociodemographic questionnaire which includes an open-ended question on essential needs during university education were administered. Pearson-Product-Moment correlations were used to explore the relationships between participants' loneliness, needs, and characteristics. Results It was found that 60.2% of the participants experienced loneliness. Economical support (81.6%), social interaction (46.9%) and psychosocial support (35%) were the essential needs during university education reported by the participants. The study findings indicate that there were significant relationships between the needs of economical support, social interaction, and loneliness level of university students. Results also show that there were significant relationships among romantic relationship, parents' status and loneliness. Participants' loneliness levels were relatively higher who had not any romantic relationship and were not from married families. Conclusion The findings of this study provided essential information, about Turkish university students, concerning: level of loneliness and relationships that exist among loneliness, needs and sociodemographic characteristics. The findings also suggest implications for psychosocial practice. Because of the mean of loneliness were found to be high (45.49 ± 10.07), for this study, professionals need to pay attention to Turkish university students' psychosocial state, and need to empower them in establishing social relations. PMID:18851744

Özdemir, Ugur; Tuncay, Tarik

2008-01-01

284

Degree Correlations in Directed Scale-Free Networks  

PubMed Central

Scale-free networks, in which the distribution of the degrees obeys a power-law, are ubiquitous in the study of complex systems. One basic network property that relates to the structure of the links found is the degree assortativity, which is a measure of the correlation between the degrees of the nodes at the end of the links. Degree correlations are known to affect both the structure of a network and the dynamics of the processes supported thereon, including the resilience to damage, the spread of information and epidemics, and the efficiency of defence mechanisms. Nonetheless, while many studies focus on undirected scale-free networks, the interactions in real-world systems often have a directionality. Here, we investigate the dependence of the degree correlations on the power-law exponents in directed scale-free networks. To perform our study, we consider the problem of building directed networks with a prescribed degree distribution, providing a method for proper generation of power-law-distributed directed degree sequences. Applying this new method, we perform extensive numerical simulations, generating ensembles of directed scale-free networks with exponents between 2 and 3, and measuring ensemble averages of the Pearson correlation coefficients. Our results show that scale-free networks are on average uncorrelated across directed links for three of the four possible degree-degree correlations, namely in-degree to in-degree, in-degree to out-degree, and out-degree to out-degree. However, they exhibit anticorrelation between the number of outgoing connections and the number of incoming ones. The findings are consistent with an entropic origin for the observed disassortativity in biological and technological networks. PMID:25310101

Williams, Oliver; Del Genio, Charo I.

2014-01-01

285

Statistics Tutorials Based on SPSS and Minitab  

NSDL National Science Digital Library

This collection of tutorials, authored by Thomas W. MacFarland of Nova Southeastern University, demonstrates various statistical topics with data and provides SPSS and Minitab code. Topics covered: measures of central tendency, sign test, Chi-square, Mann-Whitney test, Wilcoxon matched-pairs signed-ranks test, Kruskal-Wallis one-way analysis of variance, Friedman two-way analysis of variance, Spearman rank correlation, Pearson product-moment correlation, multiple regression, t-test for independent samples, t-test for matched pairs, one and two-Way ANOVA. This is a nice collection of tutorials for anyone interested in a more in-depth study of statistics.

MacFarland, Thomas W.

286

IAA Correlator Center  

NASA Technical Reports Server (NTRS)

The activities of the six-station IAA RAS correlator include regular processing of national geodetic VLBI programs Ru-E, Ru-U, and Ru-F. The Ru-U sessions have been transferred in e-VLBI mode and correlated in the IAA Correlator Center automatically since 2011. The DiFX software correlator is used at the IAA in some astrophysical experiments.

Surkis, Igor; Ken, Voitsekh; Melnikov, Alexey; Mishin, Vladimir; Sokolova, Nadezda; Shantyr, Violet; Zimovsky, Vladimir

2013-01-01

287

Reverse Correlation in Neurophysiology  

ERIC Educational Resources Information Center

This article presents a review of reverse correlation in neurophysiology. We discuss the basis of reverse correlation in linear transducers and in spiking neurons. The application of reverse correlation to measure the receptive fields of visual neurons using white noise and m-sequences, and classical findings about spatial and color processing in…

Ringach, Dario; Shapley, Robert

2004-01-01

288

Probabilistic Alert Correlation  

Microsoft Academic Search

With the growing deployment of host and network intrusion detection systems, managing reports from these systems becomes critically important. We present a probabilistic approach to alert correlation, extending ideas from multisensor data fusion. Features used for alert correlation are based on alert content that anticipates evolving IETF standards. The probabilistic approach provides a unified mathematical framework for correlating alerts that

Alfonso Valdes; Keith Skinner

2001-01-01

289

What Is Strong Correlation?  

ERIC Educational Resources Information Center

Interpretation of correlation is often based on rules of thumb in which some boundary values are given to help decide whether correlation is non-important, weak, strong or very strong. This article shows that such rules of thumb may do more harm than good, and instead of supporting interpretation of correlation--which is their aim--they teach a…

Kozak, Marcin

2009-01-01

290

Correlation between lidar-derived intensity and passive optical imagery  

NASA Astrophysics Data System (ADS)

When LiDAR data are collected, the intensity information is recorded for each return, and can be used to produce an image resembling those acquired by passive imaging sensors. This research evaluated LiDAR intensity data to determine its potential for use as baseline imagery where optical imagery are unavailable. Two airborne LiDAR datasets collected at different point densities and laser wavelengths were gridded and compared with optical imagery. Optech Orion C200 laser data were compared with a corresponding 1541 nm spectral band from the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). Optech ALTM Gemini LiDAR data collected at 1064 nm were compared to the WorldView-2 (WV-2) 949 - 1043 nm NIR2 band. Intensity images were georegistered and spatially resampled to match the optical data. The Pearson Product Moment correlation coefficient was calculated between datasets to determine similarity. Comparison for the full LiDAR datasets yielded correlation coefficients of approximately 0.5. Because LiDAR returns from vegetation are known to be highly variable, a Normalized Difference Vegetation Index (NDVI) was calculated utilizing the optical imagery, and intensity and optical imagery were separated into vegetation and nonvegetation categories. Comparison of the LiDAR intensity for non-vegetated areas to the optical imagery yielded coefficients greater than 0.9. These results demonstrate that LiDAR intensity data may be useful in substituting for optical imagery where only LiDAR is available.

Metcalf, Jeremy P.; Kim, Angela M.; Kruse, Fred A.; Olsen, Richard C.

2014-06-01

291

Correlations of coronary plaque wall thickness with wall pressure and wall pressure gradient: a representative case study  

PubMed Central

Background There are two major hemodynamic stresses imposed at the blood arterial wall interface by flowing blood: the wall shear stress (WSS) acting tangentially to the wall, and the wall pressure (WP) acting normally to the wall. The role of flow wall shear stress in atherosclerosis progression has been under intensive investigation, while the impact of blood pressure on plaque progression has been under-studied. Method The correlations of wall thickness (WT) with wall pressure (WP, blood pressure on the lumen wall) and spatial wall pressure gradient (WPG) in a human atherosclerotic right coronary artery were studied. The pulsatile blood flow was simulated using a three dimensional mathematical model. The blood was treated as an incompressible viscous non-Newtonian fluid. The geometry of the artery was re-constructed using an in vivo intravascular ultrasound (IVUS) 44-slice dataset obtained from a patient with consent obtained. The WT, the WP and the WPG were averaged on each slice, respectively, and Pearson correlation analysis was performed on slice averaged base. Each slice was then divided into 8 segments and averaged vessel WT, WP and WPG were collected from all 352 segments for correlation analysis. Each slice was also divided into 2 segments (inner semi-wall of bend and outer semi-wall of bend) and the correlation analysis was performed on the 88 segments. Results Under mean pressure, the Pearson coefficient for correlation between WT and WP was r?=?? 0.52 (p?Pearson coefficient for correlation between WT and WPG was r?=?0.30 (p?=?0.004) by 2-segment analysis and r?=?0.45 (p?=?0.002) by slice averaged analysis, respectively. The r-values corresponding to systole and diastole pressure conditions were similar. Conclusions Results from this representative case report indicated that plaque wall thickness correlated negatively with wall pressure (r?=??0.81 by slice) and positively with wall pressure gradient (r?=?0.45). The slice averaged WT has a strong linear relationship with the slice averaged WP. Large-scale patient studies are needed to further confirm our findings. PMID:22839647

2012-01-01

292

Correlation of Space Shuttle Landing Performance with Post-Flight Cardiovascular Dysfunction  

NASA Technical Reports Server (NTRS)

Introduction: Microgravity induces cardiovascular adaptations resulting in orthostatic intolerance on re-exposure to normal gravity. Orthostasis could interfere with performance of complex tasks during the re-entry phase of Shuttle landings. This study correlated measures of Shuttle landing performance with post-flight indicators of orthostatic intolerance. Methods: Relevant Shuttle landing performance parameters routinely recorded at touchdown by NASA included downrange and crossrange distances, airspeed, and vertical speed. Measures of cardiovascular changes were calculated from operational stand tests performed in the immediate post-flight period on mission commanders from STS-41 to STS-66. Stand test data analyzed included maximum standing heart rate, mean increase in maximum heart rate, minimum standing systolic blood pressure, and mean decrease in standing systolic blood pressure. Pearson correlation coefficients were calculated with the null hypothesis that there was no statistically significant linear correlation between stand test results and Shuttle landing performance. A correlation coefficient? 0.5 with a p<0.05 was considered significant. Results: There were no significant linear correlations between landing performance and measures of post-flight cardiovascular dysfunction. Discussion: There was no evidence that post-flight cardiovascular stand test data correlated with Shuttle landing performance. This implies that variations in landing performance were not due to space flight-induced orthostatic intolerance.

McCluskey, R.

2004-01-01

293

The t-test Tutorial: Comparing Cultures  

NSDL National Science Digital Library

This tutorial, created by Dale Berger of Claremont Graduate University, takes the learner step-by-step in applying descriptive and inferential statistics using a real world situation. The site focuses on the cultural differences in child rearing in the countries of Belize and Samoa. Overall, this is a great site for applied statistical theories.

Berger, Dale

294

Correlation between nitrogen fixation rate and alginate productivity of an indigenous Azotobacter vinelandii from Iran  

PubMed Central

Background and Objectives Azotobacter vinelandii, a gamma-proteobacterium, is an obligate aerobic free-living gram-negative soil bacterium capable of fixing nitrogen. Oxygen transfer rate into the cell is reduced by the increase of alginate concentrations during the course of A. vinelandii cultivation. This phenomenon provides a low intracellular oxygen concentration needed for nitrogenase activity. The aim of this study was to design a simple strategy to explain the alginate production, cell growth and nitrogenase activity correlation in A. vinelandii under aerobic conditions. Material and Methods Thirty-five different soil samples were taken from the rhizosphere of agricultural crops of Iran. Enrichment and isolation strategies were employed for microbial isolation. Physiological and biochemical characteristics were determined. Molecular identification was performed using selective nifH-g1 primers. Alginate production and nitrogenase activity assay by each isolate of Azotobacter were carried out. Bacterial growth, alginate production and Nitrogenase activity were conducted by time-coursed quantitative measurements. Results Total of 26 isolates were selected after enrichment, isolation, and screening. The isolate was identified by molecular tests as A. vinelandii. The highest alginate productions of 1.02 g/l and 0.91g/l were noted after 4 days in 8 isolates, cell biomass of which were estimated 4.88-5.26 g/l. Six of 8 isolates were able to fix atmospheric N2 on nitrogen-free medium. Rates obtained in isolates were in the range of 12.1 to 326.4 nmol C2H4 h-1 vial-1. Conclusions Nitrogen fixation and alginate production yielded significant and positive Pearson's correlation coefficient of R2 = 0.760, p ? 0.02. Finally association between bacterial growth, alginate production and nitrogenase activity almost noticeable yielded significant and positive Pearson's correlation coefficient R2= 0.723, p ? 0.04. PMID:23066492

Nosrati, R; Owlia, P; Saderi, H; Olamaee, M; Rasooli, I; Akhavian, Tehrani A

2012-01-01

295

Fuzzy correlation analysis with realization  

NASA Astrophysics Data System (ADS)

The fundamental concept of fuzzy correlation is briefly discussed. Based on the correlation coefficient of classic correlation, polarity correlation and fuzzy correlation, the relationship between the correlations are analyzed. A fuzzy correlation analysis has the merits of both rapidity and accuracy as some amplitude information of random signals has been utilized. It has broad prospects for application. The form of fuzzy correlative analyzer with NLX 112 fuzzy data correlator and single-chip microcomputer is introduced.

Tang, Yue Y.; Fan, Xinrui; Zheng, Ying N.

1998-10-01

296

Giant gravitons and correlators  

E-print Network

We calculate non-extremal correlators of Schur polynomials and single trace operators. We analyse their dual descriptions from the approach of the variation of DBI and WZ actions of the giant gravitons. We show a regularization procedure under which the extremal correlators of Schur polynomials and single trace operators match exactly with string theory computation. Other aspects of the extremal and non-extremal correlators are also discussed.

Hai Lin

2012-11-20

297

Notes on correlation femtoscopy  

SciTech Connect

The particle correlations at small relative velocities are sensitive to the space-time characteristics of the production processes on a femtometer scale owing to the effects of quantum statistics and finalstate interaction. Though the final-state interaction complicates the correlation analysis, it is an important source of information allowing for coalescence femtoscopy, correlation femtoscopy with unlike particles including access to the relative space-time asymmetries in particle production, and a study of strong interactions between specific particles. I will briefly discuss the history and basics of correlation femtoscopy, some of the recent results from femtoscopy of relativistic heavy-ion collisions, and their consequences.

Lednicky, R., E-mail: lednicky@fzu.c [Joint Institute for Nuclear Research (Russian Federation)

2008-09-15

298

Almost quantum correlations.  

PubMed

Quantum theory is not only successfully tested in laboratories every day but also constitutes a robust theoretical framework: small variations usually lead to implausible consequences, such as faster-than-light communication. It has even been argued that quantum theory may be special among possible theories. Here we report that, at the level of correlations among different systems, quantum theory is not so special. We define a set of correlations, dubbed 'almost quantum', and prove that it strictly contains the set of quantum correlations but satisfies all-but-one of the proposed principles to capture quantum correlations. We present numerical evidence that the remaining principle is satisfied too. PMID:25697645

Navascués, Miguel; Guryanova, Yelena; Hoban, Matty J; Acín, Antonio

2015-01-01

299

Almost quantum correlations  

NASA Astrophysics Data System (ADS)

Quantum theory is not only successfully tested in laboratories every day but also constitutes a robust theoretical framework: small variations usually lead to implausible consequences, such as faster-than-light communication. It has even been argued that quantum theory may be special among possible theories. Here we report that, at the level of correlations among different systems, quantum theory is not so special. We define a set of correlations, dubbed ‘almost quantum’, and prove that it strictly contains the set of quantum correlations but satisfies all-but-one of the proposed principles to capture quantum correlations. We present numerical evidence that the remaining principle is satisfied too.

Navascués, Miguel; Guryanova, Yelena; Hoban, Matty J.; Acín, Antonio

2015-02-01

300

Pairwise Correlations of Eight Strong DIBs and N(H), N(H2), and EB-V  

NASA Astrophysics Data System (ADS)

We discuss the correlations between equivalent widths of eight diffuse interstellar bands (DIBs), and examine their correlations with the column densities of atomic hydrogen (N(H)) and molecular hydrogen (N(H2)), and EB-V. The DIBs are centered at ? 5780.5, 6204.5, 6283.8, 6196.0, 6613.6, 5705.1, 5797.1, and 5487.7, in decreasing order of Pearson's correlation coefficient with N(H), which ranges from 0.94 to 0.78. The equivalent width of 5780.5 is better correlated with column density of H than with EB-V or H2, and the same is true for six of the seven other DIBs presented here. Hence, they are not preferentially located in the densest, most UV shielded parts of interstellar clouds. These eight strong DIBs are not correlated well enough with each other to suggest they come from the same carrier. However, the correlations may be useful in deriving interstellar parameters, such as N(H) from W(5780.5), when more direct methods are not available. Our future plans include mapping the distribution of DIBs in interstellar clouds, closer examination of the excellent correlation between 5705.1 and 5780.5 (almost as good as the near perfect correlation of 6613.6 with 6196.0), and precise measurements of broad DIBs.

Friedman, Scott D.; York, D. G.; McCall, B. J.; Dahlstrom, J.; Sonnentrucker, P.; Welty, D. E.; Drosback, M. M.; Hobbs, L. M.; Rachford, B. L.; Snow, T. P.

2011-10-01

301

Ultrasound Thickness of Bladder Wall in Continent and Incontinent Women and Its Correlation with Cystometry  

PubMed Central

Objective. To compare bladder wall thickness in two kinds of urinary incontinent women—stress urinary incontinence (SUI) and overactive bladder (OAB) with urodynamic detrusor overactivity (DO), and to compare them with continent patients by ultrasound, also, correlate with cystometric results in incontinent women. Methods. 91 women were divided into the following groups: continent (n = 31), SUI (n = 30), and DO (n = 30) groups after clinical evaluation and urodynamic test (only in incontinent women). Transvaginal ultrasound was performed to the bladder wall thickness (BWT) measurement. The mean of BWT was calculated and data were analyzed with ANOVA and Turkey's multiple comparison tests. Pearson's correlation coefficient (r) was used to compare two variables. Receiver operating characteristic (ROC) curve was performed to study BWT as a diagnostic parameter. Results. BWT in DO group was significantly higher than that in the other groups (P < 0.005). A moderate positive correlation was found between BWT and maximum bladder pressure during involuntary bladder contraction. There was no difference in BWT between SUI and continent groups. DO group had lower first desire to void and cystometric capacity. Maximum bladder pressure at detrusor contraction had a moderate positive correlation with BWT. The ROC revealed an area under the curve of 0.962 (95%?CI, 0.90–1.01). Conclusions. DO patients have increased bladder wall thickness, lower first desire to void, and lower cystometric capacity. There was a moderate correlation between BWT and maximum bladder pressure during involuntary bladder contraction. PMID:25538959

Otsuki, Edney Norio; Oliveira, Emerson; Sartori, Marair Gracio Ferreira; Girão, Manoel João Batista Castelo; Jármy-Di Bella, Zsuzsanna Ilona Katalin

2014-01-01

302

The Correlation between Emotional Intelligence and Instable Personality in Substance Abusers  

PubMed Central

Background Substance dependence has recently turned into one of the most important social problems. Clinical findings have shown personality traits, social relations, attitudes and values, along with emotional intelligence factors such as emotions, feelings, emotions management, challenging with problems, problem solving, tolerating psychological pressure, impulse control, self esteem and interpersonal relations, to affect substance dependence. Consequently, understanding the meaning and developing tools for assessment of emotional intelligence are significantly vital in human psychological health. This study aimed to investigate the relation between emotional intelligence and instable personality in substance abusers. Methods The present correlational study selected 80 male addicts through available sampling. The subjects referred to the Therapeutic Community Center and Kimia, Yas, and Aban Clinics in Yazd, Iran. Their emotional intelligence and personality were evaluated by BarOn questionnaire and Eysenck personality questionnaire (EPQ) for adults, respectively. Pearson's correlation coefficient was used to assess the correlations between different factors. Findings There was a negative significant correlation (P = 0.050) between emotional intelligence and instable personality in substance abusers. Problem solving and optimism (P = 0.001), interpersonal relation (P = 0.010), self esteem (P = 0.013), and realities (P = 0.017) had significant effects on instable personality. Conclusion Based on our findings, emotional intelligence was significantly correlated with instable personality in substance abusers. However, using more accurate tools in order to assess all aspects of personality can give better results. PMID:24494128

Haj Hosseini, Fatemeh; Mehdizadeh Zare Anari, Ali

2011-01-01

303

Measurements of journal use: an analysis of the correlations between three methods.  

PubMed

Rapid journal price increases have made essential that libraries have reliable and efficient measures of the importance of individual journals to local clientele. Three key measures are in-house use, circulation, and citation by faculty. This paper examines the correlations between these three measures at an academic health sciences library. Data were gathered from 1992 to 1994 using each of the three methods. Each set of data was compared with the other two, and for each pair of data sets both Spearman Rank Order and Pearson Product-Moment correlation coefficients were calculated to examine the degree of correlation between the two sets. All of the correlation coefficients were positive and statistically significant (P < 0.0001). This information suggests that if gathering many types of use data is impractical, one method may be used with the confidence that it correlates with other types of use. Visual inspection of the data confirms this with one exception: many clinical review titles tend to have a low local citation rate but high in-house use and circulation rates, suggesting that these are being used for educational and clinical purposes but not for research. PMID:9934525

Blecic, D D

1999-01-01

304

Explorations in Statistics: Correlation  

ERIC Educational Resources Information Center

Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This sixth installment of "Explorations in Statistics" explores correlation, a familiar technique that estimates the magnitude of a straight-line relationship between two variables. Correlation is meaningful only when the…

Curran-Everett, Douglas

2010-01-01

305

Correlation among auto-refractor, wavefront aberration, and subjective manual refraction  

NASA Astrophysics Data System (ADS)

Three optometry methods which include auto-refractor, wavefront aberrometer and subjective manual refraction were studied and compared in measuring low order aberrations of 60 people"s 117 normal eyes. Paired t-test and linear regression were used to study these three methods" relationship when measuring myopia with astigmatism. In order to make the analysis more clear, we divided the 117 normal eyes into different groups according to their subjective manual refraction and redid the statistical analysis. Correlations among three methods show significant in sphere, cylinder and axis in all groups, with sphere"s correlation coefficients largest(R>0.98, P<0.01) and cylinder"s smallest (0.90t-test before grouping showed the difference of three optometry methods in measuring sphere was significant (P<0.01) while axis"s difference was not significant (P>0.01). Auto-refractor had significant change from the other two methods when measuring cylinder (P<0.01). The results after grouping differed a little from the analysis among total people. Although three methods showed significant change from each other in certain parameters, the amplitude of these differences were not large, which indicated that the coherence of auto-refractor, wavefront aberrometer and subjective refraction is good. However, we suggested that wavefront aberration measurement could be a good starting point of optometry, subjective refraction is still necessary for refinement.

Li, Qi; Ren, Qiushi

2005-01-01

306

Explorations in statistics: correlation  

NSDL National Science Digital Library

Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This sixth installment of Explorations in Statistics explores correlation, a familiar technique that estimates the magnitude of a straight-line relationship between two variables. Correlation is meaningful only when the two variables are true random variables: for example, if we restrict in some way the variability of one variable, then the magnitude of the correlation will decrease. Correlation cannot help us decide if changes in one variable result in changes in the second variable, if changes in the second variable result in changes in the first variable, or if changes in a third variable result in concurrent changes in the first two variables. Correlation can help provide us with evidence that study of the nature of the relationship between x and y may be warranted in an actual experiment in which one of them is controlled.

PhD Douglas Curran-Everett (National Jewish Medical and Research Center Div. Biostatistics, Depts. Prev. Med./Biometrics, Physiology/Biophys)

2010-10-01

307

Spatial and time correlation of thermometers and pluviometers in a weather network database  

NASA Astrophysics Data System (ADS)

A basic issue that arises when analysing data bases from weather networks is the correlation system that characterizes the set of weather stations. Some statistical models being used for simulating temperature and precipitation or estimating missing data often exploit the Pearson's correlation coefficient, whereby a selection of predictors is carried out. In this paper, a specific analysis was made to understand the relationship between the distances (between the stations) and the correlation structure (of the network) and to assess the evolution of the stations ranking over the time from the network establishment, given that they were ranked on the basis of their correlation coefficient values with a target station. This study was first carried out over the whole of the Veneto region in Northeast Italy, and subsequently, it was repeated, subdividing the area into three main climatic zones: mountain, plain and coast. The variables that are involved in this study are the following: daily precipitation and daily maximum, mean and minimum temperature. Generally, the correlation coefficients of the database of precipitation are, on average, inversely proportional to the mean distances from the target station. Considering that the same behaviour was not detected on analysing the temperature database, the main results of this work can be summarized as follows: (1) the most correlated stations of precipitation are generally closer to a target station than the most correlated stations of temperature (entire area); (2) starting from 5.5 years after the network was established, the temperature variable is characterized by a high stability (over time) of the correlation rankings, up to a wide radius from the target station; (3) this trend is not so clear in precipitation data. However, when taking into account the first result, (4) generally, the most correlated stations are placed within the radius of stability, more frequently so for precipitation than for temperature.

Tardivo, Gianmarco

2014-04-01

308

Correlations for the Stroop Color and Word Test with measures of reading and language achievement.  

PubMed

The present investigation examined the relationships for scores on the Stroop Color and Word Test with measures of reading and language achievement within an adult population. The Stroop Color and Word Test, Nelson-Denny Reading Test, Woodcock-Johnson Psycho-Educational Battery-Revised, and Wide Range Achievement Test-3 were administered to 99 men ranging in age from 18 to 27 years. Pearson product-moment correlations indicated that the Stroop Word task was positively associated with scores on the WRAT-3 Spelling task, the Woodcock-Johnson Basic and Broad Reading tasks, and the Nelson-Denny Rcading Rate and Comprehension tasks. These and other significant relationships were discussed in terms of possible implications regarding the assessment of reading achievement. PMID:12027339

Leverett, J Patrick; Lassiter, Kerry S; Buchanan, Gray M

2002-04-01

309

High correlation of double Debye model parameters in skin cancer detection.  

PubMed

The double Debye model can be used to capture the dielectric response of human skin in terahertz regime due to high water content in the tissue. The increased water proportion is widely considered as a biomarker of carcinogenesis, which gives rise of using this model in skin cancer detection. Therefore, the goal of this paper is to provide a specific analysis of the double Debye parameters in terms of non-melanoma skin cancer classification. Pearson correlation is applied to investigate the sensitivity of these parameters and their combinations to the variation in tumor percentage of skin samples. The most sensitive parameters are then assessed by using the receiver operating characteristic (ROC) plot to confirm their potential of classifying tumor from normal skin. Our positive outcomes support further steps to clinical application of terahertz imaging in skin cancer delineation. PMID:25570059

Truong, Bao C Q; Tuan, H D; Fitzgerald, Anthony J; Wallace, Vincent P; Nguyen, H T

2014-08-01

310

Diagnostic role of magnetic resonance cholangiopancreatography in evaluation of obstructive biliopathies and correlating it with final diagnosis and clinical profile of patients  

PubMed Central

Aims and Objective: We assessed the utility of magnetic resonance cholangiopancreatography (MRCP) as a noninvasive diagnostic tool in patients with obstructive biliopathies. Materials and Methods: A prospective study was conducted on 54 patients with clinically suspected biliary obstruction. MRCP in these patients was compared and correlated with final diagnosis and their clinical profile. Statistical Analysis: Sample profile was described in terms of sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy. Pearson's Chi-square statistics was used to assess the strength of association between diagnostic accuracy of MRCP and final diagnosis. Results: Out of the 54 patients, 50 had biliary obstruction. The cause of biliary obstruction was finally identified on the basis of direct cholangiography/surgery/histopathology. In 52 of the 54 patients, MRCP agreed with final diagnosis in identifying the level of block. MRCP agreed with final diagnosis in identifying the cause of obstruction in 48 of the 54 patients (89%). Sensitivity of MRCP in identifying the level of obstruction in comparison with final diagnosis was 100%, while diagnostic accuracy of MRCP in identifying the level of obstruction in comparison with final diagnosis was 96.29%. The correlation between MRCP and final diagnosis in diagnosing cause of obstruction was 0.95 (Pearson's correlation coefficient, P = 0.017). Conclusion: MRCP is a safe ionizing radiation and iodinated contrast free modality which has the ability to display the biliary tree by combining the advantages of projectional and cross-sectional imaging.

Parashari, Umesh Chandra; Khanduri, Sachin; Bhadury, Samarjit; Upadhyay, Deepika; Kishore, Kaushal

2015-01-01

311

Haystack Observatory VLBI Correlator  

NASA Technical Reports Server (NTRS)

This report summarizes the activities of the Haystack Correlator during 2012. Highlights include finding a solution to the DiFX InfiniBand timeout problem and other DiFX software development, conducting a DBE comparison test following the First International VLBI Technology Workshop, conducting a Mark IV and DiFX correlator comparison, more broadband delay experiments, more u- VLBI Galactic Center observations, and conversion of RDV session processing to the Mark IV/HOPS path. Non-real-time e-VLBI transfers and engineering support of other correlators continued.

Titus, Mike; Cappallo, Roger; Corey, Brian; Dudevoir, Kevin; Niell, Arthur; Whitney, Alan

2013-01-01

312

Slowness to develop force contributes to weakness after stroke  

Microsoft Academic Search

Objective: To examine weakness after stroke, in terms of both level and rate of torque generation.Design: Descriptive. T tests for dependent and independent samples and Pearson's product moment correlation coefficients were performed.Setting: A rehabilitation unit.Participants: Ten stroke subjects, aged 56 to 81 years, undergoing rehabilitation. Ten neurologically normal subjects aged 55 to 78 years were the controls.Outcome Measures: Peak isometric

Colleen G. Canning; Louise Ada; Nicholas O'Dwyer

1999-01-01

313

Correlation of Standardized Uptake Value and Apparent Diffusion Coefficient in Integrated Whole-Body PET/MRI of Primary and Recurrent Cervical Cancer  

PubMed Central

Background To evaluate a potential correlation of the maximum standard uptake value (SUVmax) and the minimum apparent diffusion coefficient (ADCmin) in primary and recurrent cervical cancer based on integrated PET/MRI examinations. Methods 19 consecutive patients (mean age 51.6 years; range 30–72 years) with histopathologically confirmed primary cervical cancer (n?=?9) or suspected tumor recurrence (n?=?10) were prospectively enrolled for an integrated PET/MRI examination. Two radiologists performed a consensus reading in random order, using a dedicated post-processing software. Polygonal regions of interest (ROI) covering the entire tumor lesions were drawn into PET/MR images to assess SUVmax and into ADC parameter maps to determine ADCmin values. Pearson’s correlation coefficients were calculated to assess a potential correlation between the mean values of ADCmin and SUVmax. Results In 15 out of 19 patients cervical cancer lesions (n?=?12) or lymph node metastases (n?=?42) were detected. Mean SUVmax (12.5±6.5) and ADCmin (644.5±179.7×10?5 mm2/s) values for all assessed tumor lesions showed a significant but weak inverse correlation (R?=??0.342, p<0.05). When subdivided in primary and recurrent tumors, primary tumors and associated primary lymph node metastases revealed a significant and strong inverse correlation between SUVmax and ADCmin (R?=??0.692, p<0.001), whereas recurrent cancer lesions did not show a significant correlation. Conclusions These initial results of this emerging hybrid imaging technique demonstrate the high diagnostic potential of simultaneous PET/MR imaging for the assessment of functional biomarkers, revealing a significant and strong correlation of tumor metabolism and higher cellularity in cervical cancer lesions. PMID:24804676

Grueneisen, Johannes; Beiderwellen, Karsten; Heusch, Philipp; Buderath, Paul; Aktas, Bahriye; Gratz, Marcel; Forsting, Michael; Lauenstein, Thomas; Ruhlmann, Verena; Umutlu, Lale

2014-01-01

314

Lower Urinary Tract Symptoms, Erectile Dysfunction, and Their Correlation in Men Aged 50 Years and Above: A Cross-Sectional Survey in Beijing, China  

PubMed Central

Background The aim of this study was to investigate the correlation between incidence of lower urinary tract symptoms and erectile dysfunction in men aged ?50 years. Material/Methods A cross-sectional study was performed in 1644 men aged >50 years in Beijing. The International Index of Erectile Function (IIEF)-5 and International Prostate Symptom Score were recorded for each patient. Pearson’s chi-square test and Spearman correlation coefficients were used to analyze the International Prostate Symptom Scores and lower urinary tract symptoms, and their correlations with erectile dysfunction. Results The incidence rates of erectile dysfunction among men with mild, moderate, and severe lower urinary tract symptoms were 85.7, 93.7, and 97.9%, respectively. Interestingly, the total IIEF-5 score significantly correlated with the total International Prostate Symptom Score (r=?0.335; P<0.01), obstructive symptoms (r=?0.276; P<0.01), and irritative symptoms (r=?0.326; P<0.01). The correlation between the severity of lower urinary tract symptoms and that of erectile dysfunction was consistently maintained (r=0.304; P<0.01). Age significantly correlated with International Prostate Symptom Score (r=0.388; P<0.01), lower urinary tract symptoms severity (r=0.457; P<0.01), total IIEF-5 score (r=?0.533; P<0.01), and erectile dysfunction severity (r=0.529; P<0.01). Conclusions The incidence of lower urinary tract symptoms and erectile dysfunction in aging men increase with age, and the severity of erectile dysfunction is positively correlated with the severity of lower urinary tract symptoms. PMID:25543209

Song, Jian; Shao, Qiang; Tian, Ye; Chen, Shan

2014-01-01

315

Correlation of free-response and receiver-operating-characteristic area-under-the-curve estimates: Results from independently conducted FROC/ROC studies in mammography  

PubMed Central

Purpose: From independently conducted free-response receiver operating characteristic (FROC) and receiver operating characteristic (ROC) experiments, to study fixed-reader associations between three estimators: the area under the alternative FROC (AFROC) curve computed from FROC data, the area under the ROC curve computed from FROC highest rating data, and the area under the ROC curve computed from confidence-of-disease ratings. Methods: Two hundred mammograms, 100 of which were abnormal, were processed by two image-processing algorithms and interpreted by four radiologists under the FROC paradigm. From the FROC data, inferred-ROC data were derived, using the highest rating assumption. Eighteen months afterwards, the images were interpreted by the same radiologists under the conventional ROC paradigm; conventional-ROC data (in contrast to inferred-ROC data) were obtained. FROC and ROC (inferred, conventional) data were analyzed using the nonparametric area-under-the-curve (AUC), (AFROC and ROC curve, respectively). Pearson correlation was used to quantify the degree of association between the modality-specific AUC indices and standard errors were computed using the bootstrap-after-bootstrap method. The magnitude of the correlations was assessed by comparison with computed Obuchowski-Rockette fixed reader correlations. Results: Average Pearson correlations (with 95% confidence intervals in square brackets) were: Corr(FROC, inferred ROC) = 0.76[0.64, 0.84] > Corr(inferred ROC, conventional ROC) = 0.40[0.18, 0.58] > Corr (FROC, conventional ROC) = 0.32[0.16, 0.46]. Conclusions: Correlation between FROC and inferred-ROC data AUC estimates was high. Correlation between inferred- and conventional-ROC AUC was similar to the correlation between two modalities for a single reader using one estimation method, suggesting that the highest rating assumption might be questionable. PMID:23039631

Zanca, Federica; Hillis, Stephen L.; Claus, Filip; Van Ongeval, Chantal; Celis, Valerie; Provoost, Veerle; Yoon, Hong-Jun; Bosmans, Hilde

2012-01-01

316

Correlation of free-response and receiver-operating-characteristic area-under-the-curve estimates: Results from independently conducted FROC/ROC studies in mammography  

SciTech Connect

Purpose: From independently conducted free-response receiver operating characteristic (FROC) and receiver operating characteristic (ROC) experiments, to study fixed-reader associations between three estimators: the area under the alternative FROC (AFROC) curve computed from FROC data, the area under the ROC curve computed from FROC highest rating data, and the area under the ROC curve computed from confidence-of-disease ratings. Methods: Two hundred mammograms, 100 of which were abnormal, were processed by two image-processing algorithms and interpreted by four radiologists under the FROC paradigm. From the FROC data, inferred-ROC data were derived, using the highest rating assumption. Eighteen months afterwards, the images were interpreted by the same radiologists under the conventional ROC paradigm; conventional-ROC data (in contrast to inferred-ROC data) were obtained. FROC and ROC (inferred, conventional) data were analyzed using the nonparametric area-under-the-curve (AUC), (AFROC and ROC curve, respectively). Pearson correlation was used to quantify the degree of association between the modality-specific AUC indices and standard errors were computed using the bootstrap-after-bootstrap method. The magnitude of the correlations was assessed by comparison with computed Obuchowski-Rockette fixed reader correlations. Results: Average Pearson correlations (with 95% confidence intervals in square brackets) were: Corr(FROC, inferred ROC) = 0.76[0.64, 0.84] > Corr(inferred ROC, conventional ROC) = 0.40[0.18, 0.58] > Corr (FROC, conventional ROC) = 0.32[0.16, 0.46]. Conclusions: Correlation between FROC and inferred-ROC data AUC estimates was high. Correlation between inferred- and conventional-ROC AUC was similar to the correlation between two modalities for a single reader using one estimation method, suggesting that the highest rating assumption might be questionable.

Zanca, Federica; Hillis, Stephen L.; Claus, Filip; Van Ongeval, Chantal; Celis, Valerie; Provoost, Veerle; Yoon, Hong-Jun; Bosmans, Hilde [Department of Radiology, University Hospitals Leuven, 3000 Leuven (Belgium); Departments of Radiology and Biostatistics, University of Iowa, Iowa City, Iowa 52242-1077 and Comprehensive Access and Delivery Research and Evaluation (CADRE) Center, Iowa City VA Health Care System, Iowa City, Iowa 52246-2208 (United States); Department of Radiology, University Hospitals Leuven, 3000 Leuven (Belgium); Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213 (United States); Department of Radiology, University Hospitals Leuven, 3000 Leuven (Belgium)

2012-10-15

317

Gas-correlation lidar.  

PubMed

Basic principles for the extension of gas-correlation techniques to the lidar situation are discussed. Favorable signal-to-noise ratios and relaxed laser requirements characterize the technique. Preliminary experiments on atomic mercury are reported. PMID:19721644

Edner, H; Svanberg, S; Unéus, L; Wendt, W

1984-11-01

318

Gas-correlation lidar  

SciTech Connect

Basic principles for the extension of gas-correlation techniques to the lidar situation are discussed. Favorable signal-to-noise ratios and relaxed laser requirements characterize the technique. Preliminary experiments on atomic mercury are reported.

Edner, H.; Svanberg, S.; Uneus, L.; Wendt, W.

1984-11-01

319

Fluorescence Correlation Spectroscopy  

NSDL National Science Digital Library

This paper, which was previously published as part of an online biophysics textbook, provides detailed information about concepts related to fluorescence correlation spectroscopy. Sections of the document include writing on experimental realization, theoretical concepts, and applications of this technology.

Haustein, Elke

320

Extractable work from correlations  

E-print Network

Work and quantum correlations are two fundamental resources in thermodynamics and quantum information theory. In this work we study how to use correlations among quantum systems to optimally store work. We analyse this question for isolated quantum ensembles, where the work can be naturally divided into two contributions: a local contribution from each system, and a global contribution originating from correlations among systems. We focus on the latter and consider quantum systems which are locally thermal, thus from which any extractable work can only come from correlations. We compute the maximum extractable work for general entangled states, separable states, and states with fixed entropy. Our results show that while entanglement gives an advantage for small quantum ensembles, this gain vanishes for a large number of systems.

Martí Perarnau-Llobet; Karen V. Hovhannisyan; Marcus Huber; Paul Skrzypczyk; Nicolas Brunner; Antonio Acín

2014-11-11

321

Ozone Correlative Measurements Workshop  

NASA Technical Reports Server (NTRS)

A study was conducted to determine the necessary parameters for the correlation of data on Earth ozone. Topics considered were: (1) measurement accuracy; (2) equipment considerations (SBUV); and (3) ground based measurements to support satellite data.

Hilsenrath, E. (editor)

1985-01-01

322

Linear Regression and Correlation  

NSDL National Science Digital Library

This lesson is designed to further students' understanding of the concept of correlation as it relates to linear regression. This lesson provides links to discussions and activities related to scatter plots, correlation, and lines of best-fit as well as suggested ways to integrate them into the lesson. Finally, the lesson provides links to follow-up lessons designed for use in succession with the current one.

2011-05-24

323

Co-occurrence correlations of heavy metals in sediments revealed using network analysis.  

PubMed

In this study, the correlation-based study was used to identify the co-occurrence correlations among metals in marine sediment of Hong Kong, based on the long-term (from 1991 to 2011) temporal and spatial monitoring data. 14 stations out of the total 45 marine sediment monitoring stations were selected from three representative areas, including Deep Bay, Victoria Harbour and Mirs Bay. Firstly, Spearman's rank correlation-based network analysis was conducted as the first step to identify the co-occurrence correlations of metals from raw metadata, and then for further analysis using the normalized metadata. The correlations patterns obtained by network were consistent with those obtained by the other statistic normalization methods, including annual ratios, R-squared coefficient and Pearson correlation coefficient. Both Deep Bay and Victoria Harbour have been polluted by heavy metals, especially for Pb and Cu, which showed strong co-occurrence with other heavy metals (e.g. Cr, Ni, Zn and etc.) and little correlations with the reference parameters (Fe or Al). For Mirs Bay, which has better marine sediment quality compared with Deep Bay and Victoria Harbour, the co-occurrence patterns revealed by network analysis indicated that the metals in sediment dominantly followed the natural geography process. Besides the wide applications in biology, sociology and informatics, it is the first time to apply network analysis in the researches of environment pollutions. This study demonstrated its powerful application for revealing the co-occurrence correlations among heavy metals in marine sediments, which could be further applied for other pollutants in various environment systems. PMID:24559934

Liu, Lili; Wang, Zhiping; Ju, Feng; Zhang, Tong

2015-01-01

324

Stature and gender determination and their correlation using odontometry and skull anthropometry  

PubMed Central

Background: When the body has been mutilated, it is common to have the extremities or head amputated from the trunk. In concern with forensic odontology, an estimate must have been made based on the correlation of osteometry along with odontometry in determining sex, race and stature. Objective: The objective of this study is to investigate and correlate height and gender from odontometry and anthropometric data of the skull. Materials and Methods: The study was conducted in the Department of Oral and Maxillofacial Pathology and Microbiology, I.T.S Center for Dental studies and Research, Muradnagar, Ghaziabad (UP) with the representative study subjects of 60 patients as 30 males and 30 females in the age group of 15-25 years. The selected parameters were measured and then correlated to investigate stature and gender from odontometry and anthropometric data of the skull. Results: On linear regression analysis, the selected parameters were found to be statistically significant predictor of height. It was also established by Karl Pearson's coefficient correlation that the left mandibular canine index for female was statistically significant to show sexual dimorphism. Conclusion: In the emerging field of forensic odontology, skull anthropometry, odontometry exhibits stature determination and strong sexual dimorphism. PMID:25125917

Gupta, Amit; Kumar, Kiran; Shetty, Devi Charan; Wadhwan, Vijay; Jain, Anshi; Khanna, Kaveri Surya

2014-01-01

325

Hand skeletal maturity and its correlation with mandibular dental development  

PubMed Central

Objectives: Assessment of pubertal status and pubertal growth spurt in orthodontic patients has a considerable impact on the diagnosis, treatment plan and the outcome of orthodontic treatments. Hand-wrist radiography is routinely used to evaluate skeletal development. Some studies have shown that there is an association between bone development and different stages of dental calcification; therefore, the stages of dental calcification can be used as the first tool for diagnosis, in case there is an association. This study was performed with the aim to evaluate the association between the phases of dental development and the stages of skeletal maturity. Study design: In this study, a total of 52 patients (26 males and 26 females), referring to Mashhad School of Dentistry for orthodontic treatment, were evaluated; the subjects were within the age range of 9-14 years. Hand-wrist radiographic evaluation of skeletal maturation was performed using Fishman method. Also, the Demirjian method was used to identify the stages of dental calcification by panoramic radiographs. Independent t-test and Spearman correlation coefficient were used for data analyses. Results: The mean age of males and females was 11.05 ± 1.05 and 10.62 ± 1.12 years, respectively (p=0.156). The Spearman correlation coefficients between skeletal maturity indicators (SMIs) and developmental stages of mandibular left and right canines and second molars were significant in males only (p<0.05). Also, correlation coefficients were significant between adductor sesamoid ossification and mandibular right and left canines developmental stages in males (p<0.05). Conclusions: Findings of this study showed that the correlation between dental developmental stages and skeletal maturity only were significant in males; thus, different skeletal maturity patterns in males and females might be perceptible. Key words:Skeletal maturation, hand-wrist radiography, panoramic radiography. PMID:25136430

Pousti, Maryam; Adelianfar, Elahe

2014-01-01

326

Prevalence and Correlates of Depressive Symptoms and Resiliency among African American Women in a Community-Based Primary Health Care Center  

PubMed Central

The purpose of this cross-sectional pilot study was to determine the prevalence and correlates of depressive symptoms and resiliency among 290 African American women (AAW) in a community-based primary health care center. Descriptive statistics, Pearson product-moment correlation, and logistic regression analyses were conducted. Findings indicate that depressive symptoms are experienced by 49% of the participants, while 10% indicated a history of suicidal ideation. Participants had moderately high resiliency scores that had a statistically significant inverse relationship with depressive symptoms. This suggests that resiliency is potentially a protective factor for depressive symptoms. Depressive symptoms were positively correlated with participants’ diagnosis of at least one chronic disease. The strongest predictors of depressive symptoms were previous diagnoses of a mental health condition and unemployment. This study identifies risk and potential protective factors for depression among a clinic sample of AAW. PMID:24241263

Holden, Kisha B.; Bradford, L. Dianne; Hall, Stephanie P.; Belton, Allyson S.

2014-01-01

327

Serum Lactate Is not Correlated with Mixed or Central Venous Oxygen Saturation for Detecting Tissue Hypo Perfusion During Coronary Artery Bypass Graft Surgery: A Prospective Observational Study  

PubMed Central

Objectives: Effective assessment of tissue perfusion is highly important during Coronary Artery Bypass Graft (CABG). Mixed venous O2 saturation (Svo2) is one of the best and routinely used markers of tissue perfusion. However, this method is costly and leads to considerable complications. Thus, the present study aimed to determine whether the Svo2 can be substituted with central venous saturation (Scvo2) and if there is any correlation between lactate level and Svo2. Methods: This prospective observational study was conducted on 62 patients scheduled for CABG. After induction and maintenance of anesthesia, blood samples drawn from central venous, pulmonary artery, and radial artery were used to measure Scvo2, Svo2 and serum lactate level respectively before and after Cardio Pulmonary Bypass (CPB). Pearson’s correlation test was used to determine the correlation between Svo2 and Scvo2 as well as between Svo2 and serum lactate level. Besides, P < 0.05 was considered as statistically significant. Results: Overall, 62 Patients, 33 males (53.2%) and 29 females (46.8%) were enrolled into the present study. The most common coexisting illness was hypertension detected in 33 patients (53.2%) followed by hypercholesterolemia in 28 ones (44.4%). In this study, Svo2 was positively correlated with Scvo2 (r = 0.63, P < 0.001). However, no correlation was found between Svo2 and lactate (r = 0.124, P = 0.348). Conclusions: In summary, Scvo2 is considered as the best substitute of Svo2 for detecting tissue hypo perfusion during CPB. Although the lactate level had been considered as an appropriate marker of tissue perfusion and ischemia, it was not correlated to Svo2 during CABG. PMID:24757637

Shahbazi, Shahrbano; Khademi, Saeed; Shafa, Masih; Joybar, Reza; Hadibarhaghtalab, Maryam; Sahmeddini, Mohammad Ali

2013-01-01

328

Scatter Plots and Correlation  

NSDL National Science Digital Library

This webpage will be helpful for students learning to analyze data and create scatter plots. Specifically, these examples demonstrate how to determine correlations, or relationships, between sets of data. The slope of the line created by the data will show if there is a positive, negative, or no correlation between the sets of data. At the bottom of the page, a link is included for students who would like to learn how to create scatter plots with a graphing calculator. These examples are explained clearly and include useful graphics.

2012-08-14

329

Spinning Conformal Correlators  

E-print Network

We develop the embedding formalism for conformal field theories, aimed at doing computations with symmetric traceless operators of arbitrary spin. We use an index-free notation where tensors are encoded by polynomials in auxiliary polarization vectors. The efficiency of the formalism is demonstrated by computing the tensor structures allowed in n-point conformal correlation functions of tensors operators. Constraints due to tensor conservation also take a simple form in this formalism. Finally, we obtain a perfect match between the number of independent tensor structures of conformal correlators in d dimensions and the number of independent structures in scattering amplitudes of spinning particles in (d+1)-dimensional Minkowski space.

Miguel S. Costa; Joao Penedones; David Poland; Slava Rychkov

2015-01-23

330

Correlation between BPI Gene Upstream CpG Island Methylation and mRNA Expression in Piglets  

PubMed Central

Diarrhea and edematous disease are two major causes of mortality in postweaning piglets, and these conditions lead to huge economic losses in the swine industry. E. coli F18 is the primary causative agent of these two diseases. Bactericidal/permeability-increasing protein (BPI) plays an important role in the natural defense of the host. The aim of this study was to determine the correlation between BPI gene upstream CpG island methylation and mRNA expression. In this study, bisulfite sequencing PCR (BSP) was used to detect the methylation status of the BPI gene upstream CpG island and fluorescence quantitative PCR was used to detect BPI expression in the duodenum of piglets from birth to weaning age. BPI upstream CpG islands were shown to have many putative transcription factor binding sites, 10 CpG sites and every CpG site was methylated. The CpG island methylation level was lowest in 30-day piglets and was significantly lower than levels in 8-day piglets (p < 0.05). BPI mRNA expression was significantly higher in 30-day piglets than at any other age (p < 0.05). Pearson’s correlation analysis showed that the methylation status of the CpG island was negatively correlated with BPI mRNA expression. Statistical significances were found in CpG_1, CpG_3, CpG_4, CpG_7 and CpG_10 (p < 0.05). The data indicate that BPI expression is improved by demethylation of the BPI gene upstream CpG island. Furthermore, CpG_1, CpG_3, CpG_4, CpG_7 and CpG_10 may be critical sites in the regulation of BPI gene expression. PMID:24945309

Wang, Jing; Yin, Xuemei; Sun, Li; Sun, Shouyong; Zi, Chen; Zhu, Guoqiang; Wu, Shenglong; Bao, Wenbin

2014-01-01

331

DISCUSS: Regression and Correlation  

NSDL National Science Digital Library

This module introduces correlation and regression through topics like scatterplots, lines, slopes, intercepts, applications of regression analysis, the line of best fit, goodness of fit, assumptions and how to check them, prediction, interpolation, extrapolation, and reliability. Excel spreadsheets are used to provide examples and exercises.

Hunt, Neville

332

Image correlation velocimetry  

Microsoft Academic Search

This paper focuses on the correlation of two successive scalar images for the purpose of measuring imaged fluid motions. A method is presented for deforming, or transforming, one image to another. Taylor series expansions of the Lagrangian displacement field are used, in conjunction with an integral form of the equations of motion, to approximate this transformation. The proposed method locally

P. T. Tokumaru; P. E. Dimotakis

1995-01-01

333

Graphic Correlation Exercise  

NSDL National Science Digital Library

This is a graphic correlation lab exercise. It uses real data from a peer-reviewed journal publication by Lucy Edwards (1989). (I have manipulated the data set a little bit.) Students can finish the activity in two hours or less.

Dan Stephen

334

Correlation at sea  

NASA Astrophysics Data System (ADS)

This paper discusses an optical correlator interfaces to a FLIR and laser rangefinder to aid aircraft landing aboard an aircraft carrier. The purpose was to recognize aircraft and provide precision track in spite of the engine plume which is visible in IR images. Toward the end of the program, an opportunity arose to piggyback on tests of a Navy FLIR system, on board the USS Enterprise. The Navy's developmental FLIR and laser rangefinder were mounted on the carrier and provided excellent imagery with concurrent range data. The correlator performed a limited set of experiments at sea, tracking an aircraft from 8000 feet until almost touchdown. The challenges to the correlator we operation in a harsh environment and real time interfacing with other hardware. Real time range information controlled a series of filters in the correlator. The system fit into a standard panel rack and utilized remote alignment. The system operated during the chock of aircraft launch and landing, with no need to open up the optical box.

Hartman, Richard L.; Farr, Keith B.; McColgan, Michele W.; Smith, Ralph G.

1997-03-01

335

Yangian symmetric correlators  

NASA Astrophysics Data System (ADS)

Similarity transformations and eigenvalue relations of monodromy operators composed of Jordan-Schwinger type L matrices are considered and used to define Yangian symmetric correlators of n-dimensional theories. Explicit expressions are obtained and relations are formulated. In this way basic notions of the Quantum inverse scattering method provide a convenient formulation for high symmetry and integrability not only in lower dimensions.

Chicherin, D.; Kirschner, R.

2013-12-01

336

Point Biserial Correlation Coefficient  

NSDL National Science Digital Library

This page calculates the point biserial correlation coefficient for the case where one variable is dichotomous and the other is non-dichotomous. This page allows the user to input the data directly or copy and paste from a spreadsheet application and provides data summary.

Lowry, Richard, 1940-

337

Correlation and Regression  

NSDL National Science Digital Library

This applet allows the user to explore basic principles of correlation and regression. The user can manipulate points on a scatterplot. The user can then place a regression line on the plot and evaluate the resulting sums of squares error. An interesting feature of this applet is that it allows viewing of the sum of squares error as squares.

Berger, Dale

338

Correlates of School Stress.  

ERIC Educational Resources Information Center

As part of a continuing series of research studies on stress in schools, this study examined the construct validity of peripheral temperature at the fingertips as a measure of school stress. Measurements were made in classes selected at random from 11 volunteer schools in South Carolina. Three types of correlational studies were undertaken: (1)…

Matthews, Doris B.

339

Neuroanatomical Correlates of Intelligence  

ERIC Educational Resources Information Center

With the advancement of image acquisition and analysis methods in recent decades, unique opportunities have emerged to study the neuroanatomical correlates of intelligence. Traditional approaches examining global measures have been complemented by insights from more regional analyses based on pre-defined areas. Newer state-of-the-art approaches…

Luders, Eileen; Narr, Katherine L.; Thompson, Paul M.; Toga, Arthur W.

2009-01-01

340

DISCO: Distance and Spectrum Correlation Optimization Alignment for Two Dimensional Gas Chromatography Time-of-Flight Mass Spectrometry-based Metabolomics  

PubMed Central

A novel peak alignment algorithm using a distance and spectrum correlation optimization (DISCO) method has been developed for two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC/TOF-MS) based metabolomics. This algorithm uses the output of the instrument control software, ChromaTOF, as its input data. It detects and merges multiple peak entries of the same metabolite into one peak entry in each input peak list. After a z-score transformation of metabolite retention times, DISCO selects landmark peaks from all samples based on both two-dimensional retention times and mass spectrum similarity of fragment ions measured by Pearson’s correlation coefficient. A local linear fitting method is employed in the original two-dimensional retention time space to correct retention time shifts. A progressive retention time map searching method is used to align metabolite peaks in all samples together based on optimization of the Euclidean distance and mass spectrum similarity. The effectiveness of the DISCO algorithm is demonstrated using data sets acquired under different experiment conditions and a spiked-in experiment. PMID:20476746

Wang, Bing; Fang, Aiqin; Heim, John; Bogdanov, Bogdan; Pugh, Scott; Libardoni, Mark; Zhang, Xiang

2010-01-01

341

Chapter 8 Weather 2015 Pearson Education, Inc.  

E-print Network

of air mass and describe air masses that affect North America, and relate their qualities to source of orographic precipitation, and review an example of orographic effects in North America. · Identify various is the long-term average (e.g., over decades) of weather conditions and extremes in a region. #12;© 2015

Pan, Feifei

342

Gates, Pearson Partner on Common Core  

ERIC Educational Resources Information Center

As states and school districts grapple with how to teach the skills outlined in the new common standards, two foundations have announced a partnership aimed at crafting complete, online curricula for those standards in mathematics and English/language arts that span nearly every year of a child's precollegiate education. The announcement last…

Gewertz, Catherine

2011-01-01

343

Partner's Influences and Other Correlates of Prenatal Alcohol Use.  

PubMed

To investigate the influence of partners on alcohol consumption in pregnant women within the context of other factors. A Dutch nationwide online cross-sectional study among 158 pregnant women and their partners was conducted. To identify correlates of prenatal alcohol use, including perceived and reported partner norm (i.e. partner's belief regarding acceptability of prenatal alcohol use), partner modeling (i.e. partner's alcohol use during the woman's pregnancy) and partner support (i.e. partner's help in abstaining from alcohol during pregnancy), independent sample T-tests and Chi square tests were conducted. Correlation analyses tested the relationship between perceived and reported partner influence. Multivariate logistic hierarchical regression analyses tested the independent impact of partner's perceived and reported influence next to other correlates from the I-Change Model. Pregnant women who consumed alcohol perceived a weaker partner norm (p < 0.001) and less partner modeling (p < 0.05), with the partner reporting a weaker norm (p < 0.001), more drinking days per week (p < 0.05) and weaker support (p < 0.05). Perceived and reported partner norm, modeling and support were positively related (respectively p < 0.01, p < 0.01 and p < 0.05). The multivariate analyses demonstrated that pregnant women with a higher education who perceived lower severity of harm due to prenatal alcohol use and a weaker partner norm were more likely to use alcohol (R(2) = 0.42). This study demonstrated that perceived partner norm was the most critical of the constructs of perceived and reported partner influences in explaining prenatal alcohol use. PMID:25087003

van der Wulp, Nickie Y; Hoving, Ciska; de Vries, Hein

2015-04-01

344

[Correlation between quality of life and morbidity of the caregivers of elderly stroke patients].  

PubMed

The objective of this study was to describe the sociodemographic characteristics and the quality of life of the caregivers of elderly individuals with a stroke history, and correlate morbidity with the caregivers' quality of life scores. This is a cross-sectional household survey that interviewed the caregivers of elderly individuals using the following tools: a semi-structured instrument; the World Health Organization Quality of life-BREF; and the Brazilian Multidimensional Functional Assessment Questionnaire. Descriptive analysis and Pearson's correlation (p<0.05) were performed. Most participants were female (93.5%), with a mean age of 55.4±14.17 years, married or living with a partner (58.7%), with four to eight years of education (28.3%), and an income equivalent to one minimum wage salary (34.8%). The highest quality of life score was in the social relations domain (67.57) and the lowest was in the environmental domain (54.82). The highest number of caregiver morbidities correlated with the lowest scores in all quality of life domains. PMID:23018408

Santos, Nilce Maria de Freitas; Tavares, Darlene Mara Dos Santos

2012-08-01

345

Isoflavones profiling of soybean [Glycine max (L.) Merrill] germplasms and their correlations with metabolic pathways.  

PubMed

The isoflavone diversity (44 varieties) of the soybean, Glycine max (L.) Merrill, from China, Japan, and Korea was examined by high-performance liquid chromatography. The profiles of 12 isoflavones identified from the grains were subjected to data-mining processes, including partial least-squares discriminant analysis (PLS-DA), Pearson's correlation analysis, and hierarchical clustering analysis (HCA). Although PLS-DA did not reveal significant differences among extracts of soybean from 3 countries, the results clearly show that the variation between varieties was low. The CS02554 variety was separate from the others in the first 2 principal components of PLS-DA. HCA of these phytochemicals resulted in clusters derived from closely related biochemical pathways. Daidzin, genistin, and glycitin contents were significantly correlated with their respective malonyl glycoside contents. Daidzein content correlated positively with genistein content (r=0.8189, P<0.0001). The CS02554 variety appears to be a good candidate for future breeding programs, as it contains high levels of isoflavone compounds. These results demonstrate the use of metabolite profiling combined with chemometrics as a tool for assessing the quality of food and identifying metabolic links in biological systems. PMID:24491728

Kim, Jae Kwang; Kim, Eun-Hye; Park, Inmyoung; Yu, Bo-Ra; Lim, Jung Dae; Lee, Young-Sang; Lee, Joo-Hyun; Kim, Seung-Hyun; Chung, Ill-Min

2014-06-15

346

``A Desideratum in Spectrology'': an Editor's Lament in the Great Correlation Era  

NASA Astrophysics Data System (ADS)

Of all the known observable characteristics of the stars in the late 19th Century, classification by the appearance of their spectra was by far the most problematic. In 1904, Edwin Frost lamented that some 23 distinct classification systems had been created, yet none were universally accepted. In 1908, the applied mathematician Karl Pearson and a student evaluated correlations between spectra and other characteristics of the stars, hoping to ``look upon the stellar universe as an orderly whole ... by which we pass from chaos to an organised and locally differentiated cosmos.'' None of the major spectral systems, however, allowed them to draw any conclusions, other than state a high correlation with color. Yet, by 1917, astronomers were making correlations, and applying them, to make some pretty strong statements about the nature and history of the sidereal system as well as the lives of the stars. One of the strongest was the technique of spectroscopic parallaxes. But even its discoverer, Walter Sydney Adams, worried about what it all meant. Writing to Eddington in 1917, Adams wished that ``we had more physical knowledge regarding the interpretations of stellar spectra.'' And as E. A. Milne observed some years later, in retrospect, ``[t]here was a gap in the logical argument.'' My talk will address some historiographical issues arising from this phase in the development of modern astrophysics that hopefully will illuminate why the gap was closed in the way it was closed, and the effect it had on the continuing process of spectral classification.

DeVorkin, David

2012-09-01

347

Growth Patterns of Subway/Metro Systems Tracked by Degree Correlation  

E-print Network

Urban transportation systems grow over time as city populations grow and move and their transportation needs evolve. Typical network growth models, such as preferential attachment, grow the network node by node whereas rail and metro systems grow by adding entire lines with all their nodes. The objective of this paper is to see if any canonical regular network forms such as stars or grids capture the growth patterns of urban metro systems for which we have historical data in terms of old maps. Data from these maps reveal that the systems' Pearson degree correlation grows increasingly from initially negative values toward positive values over time and in some cases becomes decidedly positive. We have derived closed form expressions for degree correlation and clustering coefficient for a variety of canonical forms that might be similar to metro systems. Of all those examined, only a few types patterned after a wide area network (WAN) with a "core-periphery" structure show similar positive-trending degree correl...

Whitney, Daniel E

2012-01-01

348

Possible correlation of selenoprotein W with inflammation factors in chicken skeletal muscles.  

PubMed

The aim of the present study was to investigate the possible correlation of selenoprotein W (SelW) with inflammatory injury induced by dietary selenium (Se) deficiency in chicken. One-day-old male chickens were fed either a commercial diet or a Se-deficient diet for 55 days. Then, the expression levels of SelW messenger RNA (mRNA) and inflammation-related genes (NF-?B, TNF-?, iNOS, COX-2, and PTGES) in chicken skeletal muscles (wing muscle, pectoral muscle, and thigh muscle) were determined at 15, 25, 35, 45, and 55 days old, respectively. In addition, the correlation between SelW mRNA expression and inflammation-related genes were assessed. The results showed that dietary Se deficiency reduced the mRNA expression of SelW in chicken wing, pectorals, and thigh muscles. In contrast, Se deficiency increased the mRNA expression levels of inflammation-related genes in chicken skeletal muscle tissues at different time points. The Pearson's correlation coefficients showed that the mRNA expression levels of inflammation-related genes were significantly negative related to SelW (p?

Wu, Qiong; Yao, Hai-Dong; Tan, Si-Ran; Zhang, Zi-Wei; Zhu, Yao-Hong; Xu, Shiwen

2014-11-01

349

FINCH: Fresnel Incoherent Correlation Hologram  

E-print Network

6 FINCH: Fresnel Incoherent Correlation Hologram Joseph Rosen1, Barak Katz1 and Gary Brooker2 1Ben hologram is dubbed Fresnel incoherent correlation hologram (FINCH) (Rosen & Brooker, 2007a). The FINCH, in the FINCH the object is correlated with quadratic phase functions, but the correlation is carried out

Rosen, Joseph

350

Psychiatric symptoms correlate with metabolic indices in the hippocampus and cingulate in patients with mitochondrial disorders  

PubMed Central

There is increasing recognition that mitochondrial dysfunction may have a critical role in the pathophysiology of major psychiatric illnesses. Patients with mitochondrial disorders offer a unique window through which we can begin to understand the association between psychiatric symptoms and mitochondrial dysfunction in vivo. Using proton magnetic resonance spectroscopy (1H-MRS), we investigated metabolic indices in mitochondrial patients in regions of the brain that have been implicated in psychiatric illness: the caudate, cingulate cortex and hippocampus. In all, 15 patients with mitochondrial disorders and 15 age- and sex-matched controls underwent a comprehensive psychiatric assessment, including the administration of standardized psychiatric rating scales, followed by single voxel 1H-MRS of the caudate, cingulate cortex and hippocampus to measure N-acetyl aspartate (NAA), creatine (Cr), glycerophosphocholine (GPC), myoinositol and glutamate+glutamine (Glx). Pearson's correlation coefficients were used to determine correlations between metabolites and the psychiatric rating scales. Anxiety symptoms in these patients correlated with higher GPC, Glx, myoinositol and Cr in the hippocampus. Impaired level of function as a result of psychiatric symptoms correlated with higher Glx and GPC in the cingulate cortex. In summary, we found remarkably consistent, and statistically significant, correlations between anxiety and metabolic indices in the hippocampus in patients with mitochondrial disorders, while overall impairment of functioning due to psychiatric symptoms correlated with metabolic markers in the cingulate cortex. These findings lend support to the notion that mitochondrial dysfunction in specific brain regions can give rise to psychiatric symptoms. In particular, they suggest that metabolic processes in the hippocampus may have an important role in the neurobiology of anxiety. PMID:23149451

Anglin, R E; Rosebush, P I; Noseworthy, M D; Tarnopolsky, M; Mazurek, M F

2012-01-01

351

A correlation between hard gamma-ray sources and cosmic voids along the line of sight  

DOE PAGESBeta

We estimate the galaxy density along lines of sight to hard extragalactic gamma-ray sources by correlating source positions on the sky with a void catalog based on the Sloan Digital Sky Survey (SDSS). Extragalactic gamma-ray sources that are detected at very high energy (VHE; E > 100 GeV) or have been highlighted as VHE-emitting candidates in the Fermi Large Area Telescope hard source catalog (together referred to as “VHE-like” sources) are distributed along underdense lines of sight at the 2.4#27; level. There is also a less suggestive correlation for the Fermi hard source population (1.7#27;). A correlation between 10-500 GeV flux and underdense fraction along the line of sight for VHE-like and Fermi hard sources is found at 2.4#27; and 2.6#27;, calculated from the Pearson correlation coefficients of r = 0.57 and 0.47, respectively. The preference for underdense sight lines is not displayed by gamma-ray emitting galaxies within the second Fermi catalog, containing sources detected above 100 MeV, or the SDSS DR7 quasar catalog. We investigate whether this marginal correlation might be a result of lower extragalactic background light (EBL) photon density within the underdense regions and find that, even in the most extreme case of a entirely underdense sight line, the EBL photon density is only 2% less than the nominal EBL density. Translating this into gamma-ray attenuation along the line of sight for a highly attenuated source with opacity #28;(E, z) #24; 5, we estimate that the attentuation of gamma-rays decreases no more than 10%. This decrease, although non-neglible, is unable to account for the apparent hard source correlation with underdense lines of sight.

Furniss, A.; Sutter, P. M.; Primack, J. R.; Dominguez, A.

2014-11-25

352

Correlation Between Dental Arch Width and Sagittal Dento-Skeletal Morphology in Untreated Adults  

PubMed Central

Objective: Dental arch form is one of the most important characteristics of dentition. However, this dimension usually receives less attention in diagnosis or treatment planning and orthodontic patients are traditionally classified with regard to their sagittal characteristics. The objectives of this study were to investigate if a relationship exists between the dental arch width (transverse dimension) and sagittal skeletal and dental parameters in orthodontic patients. Materials and Methods: Dental casts and lateral cephalograms of 108 consecutive untreated Iranian patients (47 males and 61 females) between 16 and 31 years of age were evaluated. Arch width (AW) parameters including upper and lower inter-molar width (UIMW and LIMW) and upper and lower inter-canine width (UICW and LICW) were measured by a digital caliper. Sagittal parameters included SNA and SNB angle and Wits’ appraisal obtained from lateral cephalograms in addition to upper and lower arch length (UAL and LAL) obtained from dental casts. The correlation between the aforementioned parameters was evaluated applying Pearson correlation coefficients. Molar and canine relationship according to Angle’s classification was also recorded and the means of all parameters were compared between three occlusal relationship classes and two gender groups by means of two-way ANOVA. Results: According to statistical analysis a significant positive correlation between sagittal parameters and arch width measures exists between SNA and UICW and between LICW and LAL. Upper and lower ICW were significantly correlated, the relationship between upper and lower IMW and between UAL and LAL were significant. Among sagittal measures, both UAL and LAL were correlated with the ANB angle. The means of arch width parameters in three occlusal classes were not significantly different. Conclusion: The only significant correlation between arch width and sagittal parameters existed between UICW and SNA angle and between LICW and LAL. No significant difference of the arch width parameter was observed between the three occlusal classes. PMID:24910663

Shahroudi, Atefe Saffar; Etezadi, Tahura

2013-01-01

353

A correlation between hard gamma-ray sources and cosmic voids along the line of sight  

NASA Astrophysics Data System (ADS)

We estimate the galaxy density along lines of sight to hard extragalactic gamma-ray sources by correlating source positions on the sky with a void catalogue based on the Sloan Digital Sky Survey (SDSS). Extragalactic gamma-ray sources that are detected at very high energy (VHE; E > 100 GeV) or have been highlighted as VHE-emitting candidates in the Fermi Large Area Telescope hard source catalogue (together referred to as `VHE-like' sources) are distributed along underdense lines of sight at the 2.4? level. There is also a less suggestive correlation for the Fermi hard source population (1.7?). A correlation between 10 and 500 GeV flux and underdense fraction along the line of sight for VHE-like and Fermi hard sources is found at 2.4? and 2.6?, calculated from the Pearson correlation coefficients of r = 0.57 and 0.47, respectively. The preference for underdense sight lines is not displayed by gamma-ray emitting galaxies within the second Fermi catalogue, containing sources detected above 100 MeV, or the SDSS Data Release 7 quasar catalogue. We investigate whether this marginal correlation might be a result of lower extragalactic background light (EBL) photon density within the underdense regions and find that, even in the most extreme case of a entirely underdense sight line, the EBL photon density is only 2 per cent less than the nominal EBL density. Translating this into gamma-ray attenuation along the line of sight for a highly attenuated source with opacity ?(E, z) ˜ 5, we estimate that the attenuation of gamma-rays decreases no more than 10 per cent. This decrease, although non-negligible, is unable to account for the apparent hard source correlation with underdense lines of sight.

Furniss, A.; Sutter, P. M.; Primack, J. R.; Domínguez, A.

2015-01-01

354

Optic Nerve Head Morphology in Glaucoma Patients of African Descent is Strongly Correlated to Retinal Blood Flow  

PubMed Central

BACKGROUND/AIMS To examine the relationship between change in optic nerve head (ONH) morphology and retinal blood flow in patients with open-angle glaucoma (OAG) of African (AD) and European descent (ED) over three years. METHODS 112 patients with OAG (29 AD; 83 ED) underwent assessment of ONH morphology using Heidelberg retinal tomography (HRT-III) and retinal blood flow using confocal scanning laser Doppler. Repeated measures analysis of covariance was used to compare baseline and 3-year measurements and Pearson correlations were calculated to evaluate the relationships. RESULTS In OAG patients of AD, change in superior mean retinal blood flow was strongly, negatively correlated with change in cup/disc (C/D) area ratio (r=?0.78, p=0.020) and cup area (r=?0.75, p=0.0283) and strongly, positively correlated with change in rim area (r=0.74, p=0.0328) over three years. In OAG patients of AD, change in inferior mean retinal blood flow was strongly, negatively correlated with changes in C/D area ratio (r=?0.88, p=0.0156) and linear C/D ratio (r=?0.86, p=0.0265) over three years. In OAG patients of ED, these correlations were weak and did not reach statistical significance. DISCUSSION OAG patients of AD may have a stronger vascular component to their glaucoma pathophysiology than patients of ED. PMID:24964797

Kanakamedala, Priyanka; Harris, Alon; Siesky, Brent; Tyring, Ariel; Muchnik, Michael; Eckert, George; Tobe, Leslie Abrams

2014-01-01

355

Single nanowire optical correlator.  

PubMed

Integration of miniaturized elements has been a major driving force behind modern photonics. Nanowires have emerged as potential building blocks for compact photonic circuits and devices in nanophotonics. We demonstrate here a single nanowire optical correlator (SNOC) for ultrafast pulse characterization based on imaging of the second harmonic (SH) generated from a cadmium sulfide (CdS) nanowire by counterpropagating guided pulses. The SH spatial image can be readily converted to the temporal profile of the pulses, and only an overall pulse energy of 8 ?J is needed to acquire a clear image of 200 fs pulses. Such a correlator should be easily incorporated into a photonic circuit for future use of on-chip ultrafast optical technology. PMID:24807852

Yu, Huakang; Fang, Wei; Wu, Xiaoqin; Lin, Xing; Tong, Limin; Liu, Weitao; Wang, Aimin; Shen, Y Ron

2014-06-11

356

Digital demodulator-correlator  

NASA Technical Reports Server (NTRS)

An apparatus for demodulation and correlation of a code modulated 10 MHz signal is presented. The apparatus is comprised of a sample and hold analog-to-digital converter synchronized by a frequency coherent 40 MHz pulse to obtain four evenly spaced samples of each of the signal. Each sample is added or subtracted to or from one of four accumulators to or from the separate sums. The correlation functions are then computed. As a further feature of the invention, multipliers are each multiplied by a squarewave chopper signal having a period that is long relative to the period of the received signal to foreclose contamination of the received signal by leakage from either of the other two terms of the multipliers.

Layland, J. W.; Martin, W. L.; Zygielbaum, A. I.; Goldstein, R. M.; Hubbard, W. P. (inventors)

1978-01-01

357

Correlators in nontrivial backgrounds  

SciTech Connect

Operators in N=4 super Yang-Mills theory with an R-charge of O(N{sup 2}) are dual to backgrounds which are asymtotically AdS{sub 5}xS{sup 5}. In this article we develop efficient techniques that allow the computation of correlation functions in these backgrounds. We find that (i) contractions between fields in the string words and fields in the operator creating the background are the field theory accounting of the new geometry, (ii) correlation functions of probes in these backgrounds are given by the free field theory contractions but with rescaled propagators and (iii) in these backgrounds there are no open string excitations with their special end point interactions; we have only closed string excitations.

Mello Koch, Robert de [National Institute for Theoretical Physics, Department of Physics and Centre for Theoretical Physics, University of the Witwatersrand, Wits, 2050 (South Africa); Stellenbosch Institute for Advanced Studies, Stellenbosch (South Africa); Ives, Norman; Stephanou, Michael [National Institute for Theoretical Physics, Department of Physics and Centre for Theoretical Physics, University of the Witwatersrand, Wits, 2050 (South Africa)

2009-01-15

358

CORRELATES OF AVOWED HAPPINESS  

Microsoft Academic Search

DATA ON AVOWED HAPPINESS ARE SUMMARIZED UNDER THE HEADINGS OF (1) MEASUREMENT, RELIABILITY, AND VALIDITY; (2) DIMENSIONS; AND (3) CORRELATES. THE HAPPY PERSON EMERGES AS A YOUNG, HEALTHY, WELL-EDUCATED, WELL-PAID, EXTRAVERTED, OPTIMISTIC, WORRY-FREE, RELIGIOUS, MARRIED PERSON WITH HIGH SELF-ESTEEM, HIGH JOB MORALE, MODEST ASPIRATIONS, OF EITHER SEX, AND OF A WIDE RANGE OF INTELLIGENCE. (2 P. REF.)

WARNER R. WILSON

1967-01-01

359

DD correlations in photoproduction  

Microsoft Academic Search

Kinematic correlations between the charmed D and D mesons produced by a photon beam of mean energy 100 GeV\\/c have been measured by the NA14\\/2 experiment at CERN using a sample of almost background-free fully reconstructed DD events. The observed D and DD distributions are compared to the predictions of production models using different parameters for the charm fragmentation function

M. P. Alvarez; R. Barate; D. Bloch; P. Bonamy; P. Borgeaud; M. Burchell; H. Burmeister; J. M. Brunet; F. Calvino; M. Cattaneo; J. M. Crespo; B. D'Almagne; M. David; L. di Ciaccio; J. Dixon; P. Druet; A. Duane; J. P. Engel; A. Ferrer; T. A. Filippas; E. Fokitis; R. W. Forty; P. Foucault; E. N. Gazis; J. P. Gerber; Y. Giomataris; T. Hofmokl; E. C. Katsoufis; M. Koratzinos; C. Krafft; B. Lefievre; Y. Lemoigne; A. Lopez; W. K. Lui; C. Magneville; A. Maltezos; J. G. McEwen; T. Papadopoulou; B. Pattison; D. Poutot; M. Primout; H. Rahmani; P. Roudeau; C. Seez; R. Strub; D. Treille; P. Triscos; G. Tristram; G. Villet; A. Volte; M. Wayne; D. M. Websdale; G. Wormser; Y. Zolnierowski

1992-01-01

360

True RF correlation receiver  

NASA Astrophysics Data System (ADS)

Interferoceiver is a true correlation receiver and capable of overcoming severe problems caused by conventional super heterodyne receivers, such as range inaccuracy, Doppler range ambiguity, fratricides, excessive clutter contamination, undue inter system interference, etc. We had discussed the above capabilities in our early publications. In this paper, we will present the experimental progresses on interferoceiver as well as encountered obstacles. The technological revolution in radar and electronic warfare is within sight.

Li, Ming-Chiang

2009-05-01

361

Propensities, correlations, and metaphysics  

NASA Astrophysics Data System (ADS)

An attempt is made to defend realism and the absence of space-like causation in quantum mechanics, by invoking indeterminism and a new necessary condition for stochastic causality, we term robustness. This condition is defended against recent critical attacks by Cartwright and Jones, and by Healey, and the violation of the robustness condition in Bell-type correlation experiments is shown to follow if an appropriate interpretation of the state vector is employed.

Redhead, Michael

1992-03-01

362

Correlated model for ? hypernuclei  

NASA Astrophysics Data System (ADS)

We study the properties of hypernuclei containing one ? hyperon in the framework of the correlated basis function theory with Jastrow correlations. Fermi hypernetted chain integral equations are derived and used to evaluate energies and one-body densities of ? hypernuclei having a doubly closed shell nucleonic core in the jj coupling scheme, from carbon to lead. We also study hypernuclei having the least bound neutron substituted by the ? particle. The semirealistic Afnan and Tang nucleon-nucleon potential and Bodmer and Usmani ?-nucleon potential are adopted. The effect of many-body forces are considered by means either of a three-body ?-nucleon-nucleon potential of the Argonne type or of a density-dependent modification of the ?-nucleon interaction, fitted to reproduce the ? binding energy in nuclear matter. While Jastrow correlations underestimate the attractive contribution of the three-body ? interaction, the density-dependent potential provides a good description of the ? binding energies over all the nuclear masses range, in spite of the relative simplicity of the model.

Arias de Saavedra, F.; Co', G.; Fabrocini, A.

2001-06-01

363

Cots Correlator Platform  

NASA Astrophysics Data System (ADS)

Moore’s law is best exploited by using consumer market hardware. In particular, the gaming industry pushes the limit of processor performance thus reducing the cost per raw flop even faster than Moore’s law predicts. Next to the cost benefits of Common-Of-The-Shelf (COTS) processing resources, there is a rapidly growing experience pool in cluster based processing. The typical Beowulf cluster of PC’s supercomputers are well known. Multiple examples exists of specialised cluster computers based on more advanced server nodes or even gaming stations. All these cluster machines build upon the same knowledge about cluster software management, scheduling, middleware libraries and mathematical libraries. In this study, we have integrated COTS processing resources and cluster nodes into a very high performance processing platform suitable for streaming data applications, in particular to implement a correlator. The required processing power for the correlator in modern radio telescopes is in the range of the larger supercomputers, which motivates the usage of supercomputer technology. Raw processing power is provided by graphical processors and is combined with an Infiniband host bus adapter with integrated data stream handling logic. With this processing platform a scalable correlator can be built with continuously growing processing power at consumer market prices.

Schaaf, Kjeld; Overeem, Ruud

2004-06-01

364

Variable angle correlation spectroscopy  

SciTech Connect

In this dissertation, a novel nuclear magnetic resonance (NMR) technique, variable angle correlation spectroscopy (VACSY) is described and demonstrated with {sup 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.

Lee, Y.K. [Univ. of California, Berkeley, CA (United States)]|[Lawrence Berkeley Lab., CA (United States). Chemical Biodynamics Div.

1994-05-01

365

Pairwise Correlations Of Eight Strong DIBs And N(H), N(H2), And E(B-V)  

NASA Astrophysics Data System (ADS)

We establish correlations between equivalent widths of eight diffuse interstellar bands (DIBs), and examine their correlations with N(H), N(H2), and E(B-V). The DIBs are centered at 5780.5, 6204.5, 6283.8, 6196.0, 6613.6, 5705.1, 5797.1, and 5487.7, in decreasing order of Pearson's correlation coefficient with N(H), which range from 0.96 to 0.82. We find the equivalent width of 5780.5 is better correlated with column densities of H than with E(B-V) or H2, confirming earlier results, and the same is true for six of the seven other DIBs presented here. Despite this similarity, the eight strong DIBs chosen are not correlated well enough with each other to suggest they come from the same carrier. These DIBs are more likely to be associated with H than with H2, and hence are not preferentially located in the densest, most UV shielded parts of interstellar clouds. The correlations may be useful in deriving interstellar parameters, such as N(H) from W(5780.5), when more direct methods are not available. Our future plans include closer examination the excellent correlation between 5705.1 and 5780.5 (almost as good as the near perfect correlation of 6613.6 with 6196.0), and on precise measurements of broad DIBS (e.g. 4428.83, 4881.06) and inclusion of these better measurements in correlation studies with the main DIBs noted in this poster.

Friedman, Scott David; York, D. G.; McCall, B. J.; Dahlstrom, J.; Sonnentrucker, P.; Welty, D. E.; Drosback, M. M.; Hobbs, L. M.; Rachford, B. L.; Snow, T. P.

2011-05-01

366

Computed tomography-guided in vivo cardiac orientation and correlation with ECG in individuals without structural heart disease and in age-matched obese and older individuals.  

PubMed

The cardiac axis in a structurally normal heart is influenced by a number of factors. We investigated the anatomical and electrical cardiac axes in middle-aged individuals without structural heart disease and compared this with age-matched obese and older individuals without structural heart disease. A retrospective study of controls included those between 30 and 60 years old with a normal body mass index (BMI), who were then compared with obese individuals between 30 and 60 years old and with individuals more than 60 years old with a normal BMI. The anatomical cardiac axis was determined along the long axis by cardiac computed tomography (CT) and correlated with the electrical cardiac axis on a surface electrocardiogram (ECG) in the frontal plane. A total of 124 patients were included. In the controls (n?=?59), the mean CT axis was 38.1°?±?7.8° whilst the mean ECG axis was 51.8°?±?26.6°, Pearson r value 0.12 (P?=?0.365). In the obese (n?=?36), the mean CT axis was 25.1°?±?6.2° whilst the mean ECG axis was 20.1°?±?23.9°, Pearson r value 0.05 (P?=?0.808). In the older group (n?=?29), the mean CT axis was 34.4°?±?9.1° whilst the mean ECG axis was 34.4°?±?30.3°, Pearson r value 0.26 (P?=?0.209). Obese individuals have a more leftward rotation of both axes than age-matched normals (P <0.0001), which could be secondary to elevation of the diaphragm. Older individuals have a more leftward rotation only of their electrical cardiac axis (P?=?0.01), which could be a normal variant or reflect underlying conduction disturbances in this age group. Clin. Anat. 28:487-493, 2015. © 2015 Wiley Periodicals, Inc. PMID:25832755

Sathananthan, Gnalini; Aggarwal, Gunjan; Zahid, Simmi; Byth, Karen; Chik, William; Friedman, Daniel; Thiagalingam, Aravinda

2015-05-01

367

APPROXIMATING POWER OF THE UNCONDITIONAL TEST FOR CORRELATED BINARY PAIRS.  

PubMed

We provide a simple and good approximation of power of the unconditional test for two correlated binary variables. Suissa and Shuster (1991) described the exact unconditional test. The most commonly used statistical test in this setting, McNemar's test, is exact conditional on the sum of the discordant pairs. Although asymptotically the conditional and unconditional versions coincide, a long-standing debate surrounds the choice between them. Several power approximations have been studied for both methods (Miettinen, 1968; Bennett and Underwood, 1970; Connett, Smith, and McHugh, 1987; Connor, 1987; Suissa and Shuster, 1991; Lachenbruch, 1992; Lachin, 1992). For the unconditional approach most existing power approximations use the Gaussian distribution, while the accurate ("exact") method is computationally burdensome. A new approximation uses the F statistic corresponding to a paired-data T test computed from the difference scores of the binary outcomes. Enumeration of all possible 2 × 2 tables for small sample sizes allowed evaluation of both test size and power. The new approximation compares favorably to others due to the combination of ease of use and accuracy. PMID:24465078

Selicato, Grace R; Muller, Keith E

1998-01-01

368

Distinctive Clinical Correlates of Psychotic Major Depression: The CRESCEND Study  

PubMed Central

Objective The purpose of this investigation was to identify distinctive clinical correlates of psychotic major depression (PMD) as compared with non-psychotic major depression (NPMD) in a large cohort of Korean patients with major depressive disorder (MDD). Methods We recruited 966 MDD patients of age over 18 years from the Clinical Research Center for Depression of South Korea (CRESCEND) study. Diagnoses of PMD (n=24) and NPMD (n=942) were made with the DSM-IV definitions and confirmed with SCID. Psychometric scales were used to assess overall psychiatric symptoms (BPRS), depression (HAMD), anxiety (HAMA), global severity (CGI-S), suicidal ideation (SSI-Beck), functioning (SOFAS), and quality of life (WHOQOL-BREF). Using independent t-tests and ?2 tests, we compared clinical characteristics of patients with PMD and NPMD. A binary logistic regression model was constructed to identify factors independently associated with increased likelihood of PMD. Results PMD subjects were characterized by a higher rate of inpatient enrollment, and higher scores on many items on BPRS (somatic concern, anxiety, emotional withdrawal, guilt feelings, tension, depression, suspiciousness, hallucination, motor retardation, blunted affect and excitement) global severity (CGI-s), and suicidal ideation (SSI-Beck). The explanatory factor model revealed that high levels of tension, excitement, and suicidal ideation were associated with increased likelihood of PMD. Conclusion Our findings partly support the view that PMD has its own distinctive clinical manifestation and course, and may be considered a diagnostic entity separate from NPMD. PMID:25110501

Park, Seon-Cheol; Lee, Hwa-Young; Sakong, Jeong-Kyu; Jun, Tae-Youn; Lee, Min-Soo; Kim, Jae-Min; Kim, Jung-Bum; Yim, Hyeon-Woo

2014-01-01

369

Dynamics of Nonclassical Correlations with an Initial Correlation  

NASA Astrophysics Data System (ADS)

We investigate the dynamics of nonclassical correlations including concurrence and local quantum uncertainty in the damped Jaynes–Cummings model with an initial system–reservoir correlation. The dynamics of qubit–reservoir correlation and the influence of non-Markovian effect are studied. Furthermore, we consider the double damped Jaynes–Cummings model consisting of two noninteracting qubits locally coupled to independent reservoirs and explore the properties of both qubit–qubit and reservoir–reservoir correlations. The influences of initial correlation and non-Markovian effect on the dynamics of nonclassical correlations are analyzed. It is found that the dynamics for both qubit–qubit and reservoir–reservoir correlations can be significantly changed by the initial correlation and the non-Markovian effect. Finally, we explore the sudden changes of local quantum uncertainty and find that they are closely related to the initial system–environment entanglement.

Hu, Zheng-Da; Wang, Jicheng; Zhang, Yixin; Zhang, Ye-Qi

2014-11-01

370

Organochlorine compound residues in the eggs of broad-snouted caimans (Caiman latirostris) and correlation with measures of reproductive performance.  

PubMed

Organochlorine compounds (OCCs), like pesticides (OCPs) and polychlorinated biphenyls (PCBs), are persistent lipophilic chemicals classified as endocrine-disruptors. Caiman latirostris inhabits wetlands throughout north-eastern Argentina and may accumulate OCCs. The aims of this study were to determine OCC residues in the eggs of C. latirostris and to correlate OCC burden with clutch size, hatching success and hatchling survival as measures of reproductive performance. Fourteen caiman clutches were harvested from sites with different degrees of anthropogenic intervention on wetlands surrounding Paraná River tributaries. Two to four eggs by clutch were used to quantify OCCs. OCP residues were found in all clutches. The principal contributors to the OCPs burden were the DDT family (range BDL-153.0 ng g(-1) lipid) and oxychlordane (range BDL-34.3 ng g(-1) lipid). PCBs were present in 92.9% of the clutches (range BDL-136.6 ng g(-1) lipid). Both higher concentrations and higher diversity of pesticides, including endosulfan sulfate, were found in the nests harvested close to croplands. A negative correlation was found between clutch size and ?OCCs (p=0.02, Pearson r=-0.53, r(2)=0.28), mainly due to the ?OCPs (p=0.04, Pearson r=-0.54, r(2)=0.30). Since egg OCCs concentrations predict maternal burden, present findings suggest that higher OCCs exposure could lead to smaller clutches. Although, other factors like mother age could influence clutch size. Additionally, as caimans are a long-lived and non-migratory species, the maternal OCCs burden reflects the environmental status throughout their home range; thus, caiman eggs could be useful as a biomonitor of local contamination. PMID:21531435

Stoker, C; Repetti, M R; García, S R; Zayas, M A; Galoppo, G H; Beldoménico, H R; Luque, E H; Muñoz-de-Toro, M

2011-06-01

371

Are secular correlations between sunspots, geomagnetic activity, and global temperature significant?  

USGS Publications Warehouse

Recent studies have led to speculation that solar-terrestrial interaction, measured by sunspot number and geomagnetic activity, has played an important role in global temperature change over the past century or so. We treat this possibility as an hypothesis for testing. We examine the statistical significance of cross-correlations between sunspot number, geomagnetic activity, and global surface temperature for the years 1868-2008, solar cycles 11-23. The data contain substantial autocorrelation and nonstationarity, properties that are incompatible with standard measures of cross-correlational significance, but which can be largely removed by averaging over solar cycles and first-difference detrending. Treated data show an expected statistically- significant correlation between sunspot number and geomagnetic activity, Pearson p < 10-4, but correlations between global temperature and sunspot number (geomagnetic activity) are not significant, p = 0.9954, (p = 0.8171). In other words, straightforward analysis does not support widely-cited suggestions that these data record a prominent role for solar-terrestrial interaction in global climate change. With respect to the sunspot-number, geomagnetic-activity, and global-temperature data, three alternative hypotheses remain difficult to reject: (1) the role of solar-terrestrial interaction in recent climate change is contained wholly in long-term trends and not in any shorter-term secular variation, or, (2) an anthropogenic signal is hiding correlation between solar-terrestrial variables and global temperature, or, (3) the null hypothesis, recent climate change has not been influenced by solar-terrestrial interaction. ?? 2011 by the American Geophysical Union.

Love, J.J.; Mursula, K.; Tsai, V.C.; Perkins, D.M.

2011-01-01

372

Preoperative Change in 6-Minute Walk Distance Correlates With Early Weight Loss After Sleeve Gastrectomy  

PubMed Central

Introduction: The 6-minute walk test (6MWT) is an objective preoperative measure of functional capacity and response to intervention in patients with heart or lung disease. In bariatric surgery, there has been no reliable preoperative measure predictive of postoperative success. Here we investigated the impact of bariatric surgery on changes in distance traveled in the 6MWT (the 6MWD) and whether preoperative changes in 6MWD correlated with weight change after surgery. Methods: This is a retrospective study of consecutive patients in which the 6MWT was performed before and after laparoscopic sleeve gastrectomy for weight loss. 6MWD and total weight were measured. Pearson correlation was used to determine association between variables. Results: Of 100 patients who underwent laparoscopic sleeve gastrectomy, 31 patients had a preoperative 6MWT. Thirty patients (97%) were available for follow-up after surgery. Percentage of excess weight loss was 45.7% over an average of 7 months after surgery. There was a weak correlation between the postoperative weight loss and the change in preoperative and postoperative 6MWD (r = 0.28; P = .13). In a subset of patients who demonstrated a change in distance traveled in 2 separate preoperative 6MWD measurements (average 18.5% increase in distance), there was a strong correlation with postoperative weight loss (r = 0.82; P = .02). Conclusions: A demonstrated increase in 6MWD before surgery correlates strongly with early postoperative weight loss after laparoscopic sleeve gastrectomy. A multidisciplinary team that includes a physical therapist is useful in preparing bariatric patients for surgery. PMID:25392673

Hansen, Nathan; Hardin, Eric; Bates, Cheryl; Bellatorre, Nina

2014-01-01

373

Midwifery and Nursing Students’ Communication Skills and Life Orientation: Correlation with Stress Coping Approaches  

PubMed Central

Background: Methods learnt by nursing and midwifery students’ such as communication skills, optimisim and coping with stress would be used in their profeesional life. It is very important to promote their positive thinking and communication skills to raise coping with stress. Objectives: This cross sectional study was performed to examine the nursing and midwifery students’ communication skills and optimistic life orientation and its correlation with coping strategies with stress. Materials and Methods: The study population included 2572 students who were studying in departments of nursing and midwifery in Istanbul. The sample was included 1419 students. Three questionnaires including Communication Skills Test, Life Orientation Test and Ways of Coping Inventory were used for data collection. The data were evaluated by calculating frequency, percentage, arithmetic mean, standard deviation and Pearson correlation coefficient. Results: Students’ total mean score from the Communication Skills Scale was 165.27 ± 15.39 and for the Life Orientation Test was 18.51 ± 4.54. There was a positive correlation between their Life Orientation scores and the scores for self confidence (r = 0.34, P < 0.001), optimistic approach (r = 0.42, P < 0.001), and seeking social help (r = 0.17, P < 0.001). Also there was a significant positive correlation between Communication skill scores and self confidence (r = 0.46, P < 0.001), optimistic (r = 0.37, P < 0.001) and seeking social help approaches (r = 0.29, P < 0.001), but there was a significant negative correlation between communication skill scores and scores for helpless (r = -0.29, P < 0.001) and submissive approaches (r = -0.36, P < 0.001). Conclusions: As scores of students in optimistic life orientation and communication skills increased self confidence approach, optimistic, and social support seeking scores increased, whereas helpless, and submissive scores decreased. PMID:25414859

Özdemir, Gülsün; Kaya, Hatice

2013-01-01

374

Quantum Correlations in Dimers  

E-print Network

It has been proven that the quantum discord is a more general tool to capture non-classical correlation than quantum entanglement, because there is a non-zero quantum discord in several mixed states that could not be measured by quantum entanglement. But because of optimization part in formulating quantum discord, it is very difficult and nearly impossible to find quantum discord for some quantum states. So people proposed geometric quantum discord, which in a bipartite state could be describe as the distance of the states from the closest zero-discord state. To understand better geometric quantum discord, this paper is devoted to compare it with quantum discord and measurement induced non-locality that is in some sense dual to the geometric quantum discord. As studying the quantum correlation experimentally is one of the important thing in quantum information processing, so as our example for illustrating the difference of geometric quantum discord, quantum discord and measurement induced non-locality, our quantum system is a dimer (two spin-1/2 particles) in multiple quantum nuclear magnetic resonance.

N. Doustimotlagh

2015-03-19

375

Confinement from correlation functions  

NASA Astrophysics Data System (ADS)

We compute the Polyakov loop potential in Yang-Mills theory from the fully dressed primitively divergent correlation functions only. This is done in a variety of functional approaches ranging from functional renormalization group equations over Dyson-Schwinger equations to two-particle irreducible functionals. We present a confinement criterion that links the infrared behavior of propagators and vertices to the Polyakov loop expectation value. The present work extends the works of [J. Braun , Phys. Lett. B 684, 262 (2010)PYLBAJ0370-2693; F. Marhauser and J. M. Pawlowski, arXiv:0812.1144; J. Braun , Eur. Phys. J. C 70, 689 (2010)EPCFFB1434-6044] to general functional methods and sharpens the confinement criterion presented there. The computations are based on the thermal correlation functions in the Landau gauge calculated in [L. Fister and J. M. Pawlowski, arXiv:1112.5440; L. Fister and J. M. Pawlowski, arXiv:1112.5429; L. Fister, Ph.D. thesis, Heidelberg University, 2012].

Fister, Leonard; Pawlowski, Jan M.

2013-08-01

376

Correlation of advanced glycation endproducts estimated from skin fluorescence in first-degree relatives: the impact of adjustment for skin pigmentation.  

PubMed

The objective was to assess the relationship of skin advanced glycation endproducts (AGEs) between first-degree relatives estimated from skin fluorescence (SF) after adjustment for skin pigmentation. SF was excited by LEDs centered at 375, 405, and 420 nm from children with type 1 diabetes and their mothers. Data were adjusted to generate measures of skin intrinsic fluorescence (SIF) at the various excitation wavelengths, using 2 different pairs of correction coefficients for excitation (kx) and emission (km): kx = 0.5, km = 0.5 (not associated with skin pigmentation) and kx = 1.0, km = 0.0 (strongly associated with skin pigmentation). Pearson correlation analysis was performed, as well as a multiple variable analysis with maternal SIF adjusted for the effects of maternal age and race. There were 50 matched pairs of children and their mothers. Children were 13.3 ± 3.7 years of age and there were 19 boys/31 girls and 15 black/35 white. Mothers were 41.8 ± 6.8 years of age. The age of mother and child was highly correlated, r = .64, P < .0001. In Pearson correlation analysis, child's SIF (kx = 1.0, km = 0.0) the had strongest association with maternal SIF, while with SIF (kx = 0.5, km = 0.5) there was a trend for association. In the multiple variable model child SIF was associated with maternal SIF for all corrections and wavelengths but was stronger for kx = 1.0, km = 0.0. Even after adjustment for skin pigmentation and race, correlation of SIF between family members persists, suggesting that other genetic and/or environmental factors shared by parent and child may influence estimated skin AGEs. PMID:25411062

Báez, Eileen A; Shah, Shreepal; Felipe, Dania; Maynard, John; Chalew, Stuart

2015-03-01

377

Multichannel analysis of correlation length of SEVIRI images around ground-based cloud observatories to determine their representativeness  

NASA Astrophysics Data System (ADS)

Images of the geostationary Meteosat-9 SEVIRI instrument during the year 2012 are analyzed with respect to the representativeness of the observations of eight cloud observatories in Europe. Cloudy situations are selected to get a time series for every pixel in a 300 km × 300 km area centered around each ground station. Then the Pearson correlation coefficient of each time series to the one of the pixel nearest to the corresponding ground site is calculated. The area for which a station is representative is defined by the characteristic radius around each station for each SEVIRI channel, where the average correlation falls below 0.9. It is found that measurements in the visible and near infrared channels, which respond to cloud microphysics, are correlated in an area with a 1 to 4 km radius, while the thermal channels, that correspond to cloud top temperature, are correlated to a distance of about 20 km. The defined radius even increases for the water vapor and ozone channels. While all stations in Central Europe are quite alike, the correlations around the station in the mountains of southern Italy are much lower. Additionally correlations at different distances corresponding to the grid box sizes of forecast models were compared. The results show good comparability between regional forecast models (grid size ? 10 km) and ground-based measurements since the correlations in less than 10 km distance are in all cases higher than 0.8. For larger distances like they are typical for global models (grid size ? 20 km) the correlations decrease to 0.6, especially for shortwave measurements and corresponding cloud products. By comparing daily means, the characteristic radius of each station is increased to about 3 to 10 times the value of instantaneous measurements and also the comparability to models grows.

Slobodda, J.; Hünerbein, A.; Lindstrot, R.; Preusker, R.; Ebell, K.; Fischer, J.

2014-06-01

378

Validation of Sensor Alert Correlators  

Microsoft Academic Search

The authors describe the first experimental validation of correlation systems with the goal of assessing the overall progress in the field. Their experiment set out to measure the collective ability of correlators to recognize cyber attacks and designate their targets.

Joshua W. Haines; Dorene Kewley Ryder; Laura Tinnel; Stephen Taylor

2003-01-01

379

Magnitude correlations in global seismicity  

SciTech Connect

By employing natural time analysis, we analyze the worldwide seismicity and study the existence of correlations between earthquake magnitudes. We find that global seismicity exhibits nontrivial magnitude correlations for earthquake magnitudes greater than M{sub w}6.5.

Sarlis, N. V. [Solid State Section and Solid Earth Physics Institute, Physics Department, University of Athens, Panepistimiopolis, Zografos GR-157 84, Athens (Greece)

2011-08-15

380

Fecal Calprotectin is an Accurate Tool and Correlated to Seo Index in Prediction of Relapse in Iranian Patients With Ulcerative Colitis  

PubMed Central

Background: The natural clinical course of Ulcerative Colitis (UC) is characterized by episodes of relapse and remission. Fecal Calprotectin (FC) is a relatively new marker of intestinal inflammation and is an available, non-expensive tool for predicting relapse of quiescent UC. The Seo colitis activity index is a clinical index for assessment of the severity of UC. Objectives: The present study aimed to evaluate the accuracy of FC and the Seo colitis activity index and their correlation in prediction of UC exacerbation. Patients and Methods: In this prospective cohort study, 157 patients with clinical and endoscopic diagnosis of UC selected randomly from 1273 registered patients in Fars province’s IBD registry center in Shiraz, Iran, were followed from October 2012 to October 2013 for 12 months or shorter, if they had a relapse. Two patients left the study before completion and one patient had relapse because of discontinuation of drugs. The participants' clinical and serum factors were evaluated every three months. Furthermore, stool samples were collected at the beginning of study and every three months and FC concentration (commercially available enzyme linked immunoassay) and the Seo Index were assessed. Then univariate analysis, multiple variable logistic regression, Receiver Operating Characteristics (ROC) curve analysis, and Pearson’s correlation test (r) were used for statistical analysis of data. Results: According to the results, 74 patients (48.1%) relapsed during the follow-up (33 men and 41 women). Mean ± SD of FC was 862.82 ± 655.97 ?g/g and 163.19 ± 215.85 ?g/g in relapsing and non-relapsing patients, respectively (P < 0.001). Multiple logistic regression analysis revealed that age, number of previous relapses, FC and the Seo index were significant predictors of relapse. ROC curve analysis of FC level and Seo activity index for prediction of relapse demonstrated area under the curve of 0.882 (P < 0.001) and 0.92 1(P < 0.001), respectively. Besides, FC level of 341 ?g/g was identified as the cut-off point with 11.2% and 79.7% relapse rate below and above this point, respectively. Additionally, Pearson correlation coefficient (r) between FC and the Seo index was significant in prediction of relapse (r = 0.63, P < 0.001). Conclusions: As a simple and noninvasive marker, FC is highly accurate and significantly correlated to the Seo activity index in prediction of relapse in the course of quiescent UC in Iranian patients.

Hosseini, Seyed Vahid; Jafari, Peyman; Taghavi, Seyed Alireza; Safarpour, Ali Reza; Rezaianzadeh, Abbas; Moini, Maryam; Mehrabi, Manoosh

2015-01-01

381

Correlation between Duffy blood group phenotype and breast cancer incidence  

PubMed Central

Background Different ethnicities have different distribution of Duffy blood group (DBG) phenotypes and different breast cancer morbidity. A study in our lab demonstrated that Duffy antigen/receptor for chemokines (DARC, also known as DBGP, the Duffy protein phenotype), led to the inhibition of tumorigenesis. Therefore, we tested the hypothesis that DBGP is correlated with breast cancer occurrence. Methods DBGP proteins were examined by indirect antiglobulin testing with anti-FYa and anti-FYb antibodies. The phenotypes were classified into four groups according to the agglutination reactions: FYa + FYb+, FYa + FYb-, FYa-FYb + and FYa-FYb-. The phenotypes and pathological diagnosis of consecutively hospitalized female patients (n = 5,022) suffering from breast cancer at the Shanghai Cancer Hospital and Henan Province Cancer Hospital were investigated. The relationships between DBGP expression with breast cancer occurrence, axillary lymph status, histological subtype, tumor size pathological grade and overall survival were analyzed. Results The incidence of breast cancer was significantly different between FYa + FYb + (29.8%), FYa + FYb- (33.2%), FYa-FYb + (45.6%) and FYa-FYb- (59.1%; P = 0.001). Significant different numbers of breast cancer patients had metastases to the axillary lymph nodes in the FYa + FYb + group (25.1%), FYa + FYb- (36.9%), FYa-FYb + (41.0%) and FYa-FYb- (50.0%, (P = 0.005). There was a statistical significance (p = 0.022) of the overall survival difference between patients with difference phenotypes. No significant difference was observed in cancer size (t-test, p > 0.05), histological cancer type (Fisher's exact test, p > 0.05) or histological grade (Fisher's exact test, p > 0.05) between every each DBGP group. Conclusions DBGP is correlated with breast cancer incidence and axillary lymph node metastasis and overall survival. Further investigations are required to determine the underlying mechanism of Duffy blood group phenotype on breast cancer risk. PMID:22928984

2012-01-01

382

Lack of correlation between microbial penetration method and electro chemical technique for assessment of leakage through the root canal fillings  

PubMed Central

Aims: The purpose of this study was to compare microbial penetration method and electrochemical technique for evaluation of the apical seal. Materials and Methods: A total of 28 teeth were prepared using the step-back technique to ISO size 40 master apical files. The specimens were randomly divided into an experimental group, two positive and two negative controls. Root canals in the experimental and negative control group were filled with gutta-percha (GP) and sealer, using lateral condensation technique. In the positive control group, canals were filled with GP without any sealer. The external surface of each tooth was coated with two layers of the nail varnish, except for the access opening and the apical foramen. In the negative control group, the teeth were completely covered with nail varnish. The apical seal was recorded with two methods, each successively used on the same teeth: An electrochemical method and a bacterial penetration method. Statistical Analysis Used: The correlation of the electro chemical readings with the results obtained from bacterial micro leakage test was evaluated by Pearson's correlation coefficient. Results: Correlation coefficient of the measurements obtained from the two evaluation methods, was 0.23 (r = 0.23), so the correlation was not statistically significant (P = 0.275). Conclusions: This study shows that several studies by different methods are necessary before evaluation of the marginal leakage. PMID:24808699

Kazemipoor, Maryam; Modaresi, Jalil; Zandi, Hengameh; Vasee, Narges; Farzaneh, Vaziri

2014-01-01

383

Correlation between hybrid layer thickness, resin tag length and microtensile bond strength of a self-etching adhesive system.  

PubMed

The purpose of this study was to evaluate the correlation between the hybrid layer thickness, resin tag length and resin bond strength of a self-etching adhesive system to sound dentin tissue "in vivo". After performing restorative procedures and tooth extractions, ten specimens were sectioned in a mesiodistal direction. One dental section was used for light microscope analysis, in which both the resin tag length and hybrid layer thickness were measured, while the other section was analyzed using a microtensile test (0.5 mm/min). The fractured surface of the latter section was characterized using a stereoscopic magnifying glass (40x magnifcation). The results were subject to statistical analysis using the Pearson Correlation Test (a = 0.05). The hybrid layer thickness, resin tag length and resin bond strength mean values were 2.19 microm (0.34), 4.34 microm (0.28) and 9.73 MPa (5,55), respectively. In addition, correlation tests between the resin tag length and the resin bond strength (r=0.014) and also between the hybrid layer thickness and bond strength (r=0.43), showed no statistically significant correlation. The microtensile bond strength of Adper Prompt L Pop self-etching adhesive system does not depend on hybrid layer thickness or resin tag length. PMID:23230647

Rahal, Vanessa; de Oliveira, Fernanda G; Briso, André L F; dos Santos, Paulo H; Sundefeld, Maria L M M; Sundfeld, Renato H

2012-01-01

384

Correlations between CT perfusion parameters and vascular endothelial growth factor expression and microvessel density in implanted VX2 lung tumors.  

PubMed

To evaluate the correlation between CT perfusion parameters and tumor angiogenesis, expression of VEGF is implanted in VX2 lung tumor. VX2 tumor cells were injected in 15 healthy New Zealand rabbits. After 20 days, tumors with diameter over 7 mm were scanned with 16 row spiral CT. Using Software Perfusion 3, blood flow (BF), blood volume (BV), permeability surface area product (PS), and the maximum attenuation value (MAV) were obtained. After CT examination, rabbit was sacrificed, and slices from tumor tissue were prepared and checked with immunohistochemical staining with anti-CD34 and anti-VEGF monoclonal antibodies. Correlation of CT perfusion parameters with MVD and VEGF expression was determined by using Pearson correlation analysis. Blood supply of tumor and regions around tumor was higher than that of normal lung tissue. PS value increased sharply in tumor tissue. PS value in regions around tumor was also higher than that of normal lung tissue but lower than that of tumor tissue. Significant positive correlation was observed between CT perfusion parameters (BF, BV, PS, and MAV) and expression of VEGF and MVD in tumor tissue. CT perfusion parameters provide reliable information of the microcirculation in tumor tissue; therefore, it can be used as indexes to characterize angiogenesis of tumor. PMID:24777810

Ling, Shoujia; Deng, Dong; Mo, Yan; Zhang, Xiaobo; Guan, Xuechun; Wei, Qijun

2014-09-01

385

Significant correlation between salivary and serum Ca 15-3 in healthy women and breast cancer patients.  

PubMed

The tumor marker CA 15-3 is one of the most import reliable for metastatic breast cancer monitoring. While it is generally assessed in serum of patients, blood sampling is an invasive method compared to saliva sampling which is simple and could be an alternative to blood according to many studies. The aim of this investigation was to assess the relationship between serum and salivary concentrations of the protein CA 15-3 in patients with breast cancer and healthy asymptomatic volunteers. A case-control study was conducted with 60 women: 29 breast cancer patients from the Maternity Hospital Souissi Rabat (Morocco) and 31 healthy asymptomatic women. The CA 15-3 concentrations in saliva and serum samples were assessed using an enzyme immune assay (EIA kits) and comparison between cases and controls was made by the Mann-Whitney test. The correlation between serum and saliva CA 15-3 concentration was tested using Pearson correlation. The comparison result of CA15-3 concentration in saliva and serum level in cases and controls was not statistically significant (p>0.05). However, the correlation between salivary and serum CA 15-3 concentration was positive and statistically significant (r=0.27, p=0.03). In conclusion, the positive correlation between salivary and serum expression found in our study suggests that saliva could be an alternative to blood sampling to help breast cancer monitoring. PMID:24969900

Laidi, Fatna; Bouziane, Amal; Lakhdar, Amina; Khabouze, Samira; Amrani, Mariam; Rhrab, Brahim; Zaoui, Fatima

2014-01-01

386

Interaural correlation discrimination from diffuse field reference correlations.  

PubMed

Just noticeable differences in interaural correlation (?-jnds) from diffuse sound field reference correlations are obtained. In a three-interval, three-alternative forced-choice procedure, ?-jnds are measured for positive and negative deviations from nine narrowband reference conditions. Stimuli are 1 equivalent rectangular bandwidth wide noise bursts with center frequencies between 165 and 1500 Hz. The frequency dependent reference correlation (?ref) is determined by the simulated interaural correlation under ideal diffuse sound field conditions. Results show that the interaural correlation at threshold for deviation toward the positive correlation range follows the reference curve in a nonlinear fashion. For deviation toward the negative correlation range the interaural correlation at threshold is further afar the reference curve and does not markedly resemble its trend. The results indicate that the previously found asymmetry for correlation discrimination from uncorrelated broadband stimuli to the positive and negative correlation range becomes less pronounced for narrowband stimuli. For positive deviation, the highest jnds are found for the region where the reference curve occupies the global minimum in ?ref; despite that, the interaural correlation at threshold for positive deviation exhibits its lowest value at that point. PMID:23464020

Walther, Andreas; Faller, Christof

2013-03-01

387

Total correlations and mutual information  

E-print Network

In quantum information theory it is generally accepted that quantum mutual information is an information-theoretic measure of total correlations of a bipartite quantum state. We argue that there exist quantum states for which quantum mutual information cannot be considered as a measure of total correlations. Moreover, for these states we propose a different way of quantifying total correlations.

Zbigniew Walczak

2012-11-15

388

Truncation Of Images For Correlation  

NASA Technical Reports Server (NTRS)

Correlation performed on relatively small computer. Proposed method for processing video images in slowly changing scenes, renditions of complicated objects truncated to points, lines, polygons, or other simplified geometrical objects. Processed by image-correlating algorithms to extract information: recognize features and to track displacements of features in subsequent image frames to determine velocities. Entails correlation of far fewer data than original images.

Shimada, Katsunori

1990-01-01

389

Correlates of Desistance  

NSDL National Science Digital Library

Research has shown that marital status and employment are correlates of desistance. That is, adolescents involved with crime were more likely to discontinue offending in adulthood if they were married and had a good job. Most of what criminologists know about the process of desistance from crime is based on a sample of adult males in the 1950's. There is no question that life in America has changed drastically in the past fifty years. Given the importance of examining historical change inherent in the life course perspective, it is important to determine how changes in the social structure over time impact individuals. Therefore, the goals of this data analysis exercise are to examine changes in marriage and employment over the last fifty years. The purposes are to identify the changes that have taken place, and to hypothesize how these changes may affect the process of desistance from crime today.

Ford, Jason

390

Ultraviolet Mirau correlation microscopy  

NASA Astrophysics Data System (ADS)

We report our work towards improving the resolution performance of a conventional Mirau correlation microscope (MCM) by operating in the UV. We have modified the Mirau interferometer with the introduction of new thin-film beamsplitters that are nonattenuative in the ultra-violet, and new interferometer structure that can be made to work with short working distance objectives. Along with special UV optics, the new MCM can be made to operate in the ultra- violet region. By operating at 248 nm mercury line, the expected resolution improvement in both transverse and depth directions should be nearly doubled. A fully working MCM UV system at 325 nm is described in detail, and demonstrates the feasibility for a 248 nm system once a high quality 248 nm objective becomes available.

Chang, Fang Cheng; Kino, Gordon S.

1997-04-01

391

Hadron Correlations in CMS  

NASA Astrophysics Data System (ADS)

The measurements of the anisotropic flow of single particles and particle pairs have provided some of the most compelling evidence for the creation of a strongly interacting quark-gluon plasma (sQGP) in relativistic heavy ion collisions, first at RHIC, and more recently at the LHC. Using PbPb collision data taken in the 2010 and 2011 heavy ion runs at the LHC, the CMS experiment has investigated a broad scope of these flow phenomena. The v2 elliptic flow coefficient has been extracted with four different methods to cross-check contributions from initial state fluctuations and non-flow correlations. The measurements of the v2 elliptic anisotropy have been extended to a transverse momentum of 60 GeV/c, which will enable the placement of new quantitative constraints on parton energy loss models as a function of path length in the sQGP medium. Additionally, for the first time at the LHC, the CMS experiment has extracted precise elliptic anisotropy coefficients for the ?0 meson in the centrality range 20-80% and over a transverse momentum range 1.6 to 8 GeV/c. These results are compared with both the ?0 results reported by the PHENIX detector at RHIC, and with the inclusive charged particle anisotropy results reported from the LHC. Finally, the CMS experiment has mounted an extensive study of charged hadron pair azimuthal correlations using a Fourier harmonic decomposition to fit the data. The relationship between these pair coefficients and the single particle harmonic flow coefficients can be explored for its insight into the early dynamics of this viscous medium.

Maguire, Charles F.

2013-08-01

392

Wiener-like correlation filters  

NASA Astrophysics Data System (ADS)

We introduce a new, to our knowledge, design for a Wiener-like correlation filter, which consists of cascading a phase-only filter (POF) with a photorefractive Wiener-like filter. Its performance is compared with that of the POF and the Wiener correlation filter (WCF). Correlation results show that for intermediate and higher levels of noise this correlation filter has a peak-to-noise ratio that is larger than that of either the POF or the WCF while still preserving a correlation peak that is almost as high as that of the POF.

Khoury, Jehad; Gianino, Peter D.; Woods, Charles L.

2000-01-01

393

Wiener-like correlation filters.  

PubMed

We introduce a new, to our knowledge, design for a Wiener-like correlation filter, which consists of cascading a phase-only filter (POF) with a photorefractive Wiener-like filter. Its performance is compared with that of the POF and the Wiener correlation filter (WCF). Correlation results show that for intermediate and higher levels of noise this correlation filter has a peak-to-noise ratio that is larger than that of either the POF or the WCF while still preserving a correlation peak that is almost as high as that of the POF. PMID:18337890

Khoury, J; Gianino, P D; Woods, C L

2000-01-10

394

Additivity relations in quantum correlations  

E-print Network

Does the sum of correlations in subsystems constitute the correlation in the total system? Such a concept can be expressed by an additivity relationship of correlations. From a strong subadditivity condition of von Neumann entropy, four different additivity relations in total correlation are derived and quantified. Based upon the classification of the additivity in total correlation, we identify the corresponding additive relationships in entanglement. It is also discussed that similar relationships are satisfied for quantum discord of pure states, but it is not always true for mixed states.

Seungho Yang; Hyunseok Jeong; Wonmin Son

2013-05-15

395

Correlation between brain volume loss and clinical and MRI outcomes in multiple sclerosis  

PubMed Central

Objective: We investigated the determinants and clinical correlations of MRI-detected brain volume loss (BVL) among patients with relapsing-remitting multiple sclerosis from the phase 3 trials of fingolimod: FREEDOMS, FREEDOMS II, and TRANSFORMS. Methods: Post hoc analyses were conducted in the intent-to-treat populations from each trial and in a combined dataset of 3,635 patients from the trials and their extensions. The relationship between brain volume changes and demographic, clinical, and MRI parameters was studied in pairwise correlations (Pearson) and in multiple regression models. The relative frequency of confirmed disability progression was evaluated in the combined dataset by strata of concurrent BVL at up to 4 years. Results: Increasing age, disease duration, T2 lesion volume, T1-hypointense lesion volume, and disability were associated with reduced brain volume (p < 0.001, all). The strongest individual baseline predictors of on-study BVL were T2 lesion volume, gadolinium-enhancing lesion count, and T1-hypointense lesion volume (p < 0.01, all). During each study, BVL correlated most strongly with cumulative gadolinium-enhancing lesion count, new/enlarged T2 lesion count (p < 0.001, both), and number of confirmed on-study relapses (p < 0.01). Over 4 years in the combined dataset (mean exposure to study drug, 2.4 years), confirmed disability progression was most frequent in patients with greatest BVL. Conclusions: Rate of BVL in patients during the fingolimod trials correlated with disease severity at baseline and new disease activity on study, and was associated with worsening disability. PMID:25632085

Radue, Ernst-Wilhelm; Barkhof, Frederik; Sprenger, Till; Häring, Dieter A.; de Vera, Ana; von Rosenstiel, Philipp; Bright, Jeremy R.; Francis, Gordon; Cohen, Jeffrey A.

2015-01-01

396

Correlation of visual in vitro cytotoxicity ratings of biomaterials with quantitative in vitro cell viability measurements.  

PubMed

Medical devices and implanted biomaterials are often assessed for biological reactivity using visual scores of cell-material interactions. In such testing, biomaterials are assigned cytotoxicity ratings based on visual evidence of morphological cellular changes, including cell lysis, rounding, spreading, and proliferation. For example, ISO 10993 cytotoxicity testing of medical devices allows the use of a visual grading scale. The present study compared visual in vitro cytotoxicity ratings to quantitative in vitro cytotoxicity measurements for biomaterials to determine the level of correlation between visual scoring and a quantitative cell viability assay. Biomaterials representing a spectrum of biological reactivity levels were evaluated, including organo-tin polyvinylchloride (PVC; a known cytotoxic material), ultra-high molecular weight polyethylene (a known non-cytotoxic material), and implantable tissue adhesives. Each material was incubated in direct contact with mouse 3T3 fibroblast cell cultures for 24 h. Visual scores were assigned to the materials using a 5-point rating scale; the scorer was blinded to the material identities. Quantitative measurements of cell viability were performed using a 3-(4,5-dimethylthiozol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay; again, the assay operator was blinded to material identities. The investigation revealed a high degree of correlation between visual cytotoxicity ratings and quantitative cell viability measurements; a Pearson's correlation gave a correlation coefficient of 0.90 between the visual cytotoxicity score and the percent viable cells. An equation relating the visual cytotoxicity score and the percent viable cells was derived. The results of this study are significant for the design and interpretation of in vitro cytotoxicity studies of novel biomaterials. PMID:17932777

Bhatia, Sujata K; Yetter, Ann B

2008-08-01

397

Correlation of transcriptomic responses and metal bioaccumulation in Mytilus edulis L. reveals early indicators of stress.  

PubMed

Marine biomonitoring programs in the U.S. and Europe have historically relied on monitoring tissue concentrations of bivalves to monitor contaminant levels and ecosystem health. By integrating 'omic methods with these tissue residue approaches we can uncover mechanistic insight to link tissue concentrations to potential toxic effects. In an effort to identify novel biomarkers and better understand the molecular toxicology of metal bioaccumulation in bivalves, we exposed the blue mussel, Mytilus edulis L., to sub-lethal concentrations (0.54 ?M) of cadmium, lead, and a Cd+Pb mixture. Metal concentrations were measured in gill tissues at 1, 2, and 4 weeks, and increased linearly over the 4 week duration. In addition, there was evidence that Pb interfered with Cd uptake in the mixture treatment. Using a 3025 sequence microarray for M. edulis, we performed transcriptomic analysis, identifying 57 differentially expressed sequences. Hierarchical clustering of these sequences successfully distinguished the different treatment groups demonstrating that the expression profiles were reproducible among the treatments. Enrichment analysis of gene ontology terms identified several biological processes that were perturbed by the treatments, including nucleoside phosphate biosynthetic processes, mRNA metabolic processes, and response to stress. To identify transcripts whose expression level correlated with metal bioaccumulation, we performed Pearson correlation analysis. Several transcripts correlated with gill metal concentrations including mt10, mt20, and contig 48, an unknown transcript containing a wsc domain. In addition, three transcripts directly involved in the unfolded protein response (UPR) were induced in the metal treatments at 2 weeks and were further up-regulated at 4 weeks. Overall, correlation of tissue concentrations and gene expression responses indicates that as mussels accumulate higher concentrations of metals, initial stress responses are mobilized to protect tissues. However, given the role of UPR in apoptosis, it serves as an early indicator of stress, which once overwhelmed will result in adverse physiological effects. PMID:25016106

Poynton, Helen C; Robinson, William E; Blalock, Bonnie J; Hannigan, Robyn E

2014-10-01

398

Correlation between reflux and multichannel intraluminal impedance pH monitoring in untreated volunteers  

PubMed Central

Objective While probable causative agents have been identified (e.g., refluxate components, tobacco smoke), the definitive mechanism for inflammation-related laryngeal mucosal damage remains elusive. Multichannel intraluminal impedance combined with pH monitoring (MII/pH) has emerged as a sensitive tool for diagnosis and characterization of gastroesophageal reflux disease (GERD) with laryngopharyngeal manifestations. To determine the relationship between laryngeal signs and MII/pH, we examined correlations between Reflux Finding Score (RFS) ratings of videostroboscopic laryngeal examinations and findings from MII/pH. Study Design Correlational study. Methods Healthy, untreated volunteers (n =142) underwent reflux diagnosis using data acquired from MII/pH testing. Eight trained clinicians performed RFS ratings of corresponding laryngeal examinations. Averaged RFS ratings were compared to MII/pH data using Pearson correlation coefficients. The relationship between RFS and MII/pH findings and demographic/clinical information (age, sex, smoking status, reflux) was assessed using general linear modeling. Rater reliability was evaluated. Results Posterior commissure hypertrophy was negatively correlated with minutes of nonacid refluxate (R=-0.21, p=0.0115). General linear modeling revealed that 28-40% of the variance in ratings of ventricular obliteration, erythema/hyperemia, vocal fold edema, diffuse laryngeal edema, posterior commissure hypertrophy, and granulation/granuloma could be explained by main and interaction effects of age, sex, smoking status, and reflux. Intra- and inter-rater reliability for RFS were poor-fair. Conclusion These results support the theory that the RFS is not specific for reflux in healthy, untreated volunteers, suggesting there may be alternate explanations for inflammatory clinical signs commonly ascribed to reflux in this population. PMID:24782404

Jetté, Marie E.; Gaumnitz, Eric A.; Birchall, Martin A.; Welham, Nathan V.; Thibeault, Susan L.

2014-01-01

399

Bone marrow angiogenesis in multiple myeloma and its correlation with clinicopathological factors.  

PubMed

Increased angiogenesis has been found to be an adverse prognostic factor in solid tumors but evidences show that angiogenesis also plays an important role in hematological malignancies including multiple myeloma (MM). In this report we studied the various angiogenesis parameters like microvessel density (MVD) and total vascular area (TVA), on bone marrow biopsies in 50 newly diagnosed cases of MM. The aim was to study bone marrow angiogenesis in MM using light microscopy (MVD-A) and computerized image analyzer (MVD-B and TVA) and correlate it with clinical features, laboratory findings, histological features, and response to treatment on follow-up. Bone marrow biopsies of test cases (n = 50) were immunohistochemically stained with CD34 for visualization of microvessels. MVD-A (range 8-80; mean 50.4; SD 17.5), MVD-B (5.2-33.2; mean 16.3; SD 5.1), and TVA in percentage (range 0.42-7.20; mean 2.8; SD 1.5) were measured. Ten age- and sex-matched controls were studied and their parameters were taken as grade I. There was a significant correlation between these angiogenesis parameters (MVD-A vs MVD-B, Pearson's correlation coefficient (pcc) = 0.724; MVD-A vs TVA, pcc = 0.370; MVD-B vs TVA, pcc = 0.406). The angiogenesis was significantly higher in cases as compared to controls. Patients with residual disease had a higher MVD as compared to the complete responders. High tumor burden and diffuse pattern of infiltration were also associated with grade III MVD and TVA. Hence, it can be concluded that angiogenesis correlates with other histological features associated with prognosis and is also a good predictor for complete response in patients with multiple myeloma. PMID:20177896

Rana, Chanchal; Sharma, Seema; Agrawal, Vinita; Singh, Uttam

2010-08-01

400

Quantum correlation swapping  

NASA Astrophysics Data System (ADS)

Quantum correlations (QCs), including quantum entanglement and those different, are important quantum resources and have attracted much attention recently. Quantum entanglement swapping as a kernel technique has already been applied to quantum repeaters for successfully generating long-distance shared maximally entangled qubit states. Long-distance shared QCs containing shared entanglements are useful and important for some quantum information processing in future quantum networks. In this paper, the concept of quantum entanglement repeater is extended to that of QC repeater by generalizing quantum entanglement swapping to QC swapping. Specifically, the swapping of QCs in a pair of Werner states through a local bipartite von Neumann measurement is treated. Four different QC measures, i.e., entanglement of formation (William in Phys Rev Lett 80:2245, 1998), quantum discord (Ollivier and Zurek in Phys Rev Lett 88:017901, 2001), measurement-induced disturbance (MID) (Luo in Phys Rev A 77:022301, 2008) and ameliorated MID (Girolami et al. in J Phys A 44:352002, 2011), are employed to characterize and quantify QCs. Properties and thresholds of all QCs which occur in the swapping process are revealed, and two different phenomena are exposed and explained. It is found that a long-distance shared QC can be generated from two short-distance ones via QC swapping indeed; however, its amount cannot exceed the minimum one among the QCs in the two initial states and in the measuring state as far as the four quantifiers are concerned.

Xie, Chuanmei; Liu, Yimin; Xing, Hang; Chen, Jianlan; Zhang, Zhanjun

2015-02-01

401

Correlation of a Novel Non-Invasive Tissue Oxygen Saturation Monitor to Serum Central Venous Oxygen Saturation in Pediatric Postoperative Congenital Cyanotic Heart Disease Patients  

PubMed Central

Background Using a novel non-invasive, visible-light optical diffusion oximeter (T-Stat VLS Tissue Oximeter, Spectros Corporation, Portola Valley, CA, USA) to measure the tissue oxygen saturation (StO2) of the buccal mucosa, the correlation between StO2 and central venous oxygen saturation (ScvO2) was examined in children with congenital cyanotic heart disease undergoing a cardiac surgical procedure. Methods Paired StO2 and serum ScvO2 measurements were obtained postoperatively and statistically analyzed for agreement and association. Thirteen children (9 male) participated in the study (age range, 4 days-18 months). Surgeries included Glenn shunt procedures, Norwood procedures, unifocalization procedures with Blalock-Taussig shunt placement, a Kawashima/Glenn shunt procedure, a Blalock-Taussig shunt placement and a modified Norwood procedure. Results A total of 45 paired StO2- ScvO2 measurements were obtained. Linear regression demonstrated a Pearson’s correlation of 0.58 (95% CI: 0.35–0.75, P < 0.0001). The regression slope coefficient estimate was 0.95 (95% CI: 0.54–1.36) with an interclass-correlation coefficient of 0.48 (95% CI: 0.22–0.68). Below a clinically-relevant average ScvO2 value, a receiver operator characteristic analysis yielded an area under the curve of 0.78. Statistical methods to control for repeatedly measuring the same subjects produced similar results. Conclusion This study shows a moderate relationship and agreement between StO2 and ScvO2 measurements in pediatric patients with a history of congenital cyanotic heart disease undergoing a cardiac surgical procedure. This real-time monitoring device can act as a valuable adjunct to standard non-invasive monitoring where serum ScvO2 sampling currently assists in the diagnosis of low cardiac output following pediatric cardiac surgery. PMID:23691783

2015-01-01

402

Correlation of neurocognitive function and brain parenchyma volumes in children surviving cancer  

NASA Astrophysics Data System (ADS)

This research builds on our hypothesis that white matter damage and associated neurocognitive symptoms, in children treated for cancer with cranial spinal irradiation, spans a continuum of severity that can be reliably probed using non-invasive MR technology. Quantitative volumetric assessments of MR imaging and psychological assessments were obtained in 40 long-term survivors of malignant brain tumors treated with cranial irradiation. Neurocognitive assessments included a test of intellect (Wechsler Intelligence Test for Children, Wechsler Adult Intelligence Scale), attention (Conner's Continuous Performance Test), and memory (California Verbal Learning Test). One-sample t-tests were conducted to evaluate test performance of survivors against age-adjusted scores from the test norms; these analyses revealed significant impairments in all apriori selected measures of intelligence, attention, and memory. Partial correlation analyses were performed to assess the relationships between brain tissues volumes (normal appearing white matter (NAWM), gray matter, and CSF) and neurocognitive function. Global intelligence (r = 0.32, p = 0.05) and global attentional (r = 0.49, p < 0.01) were significantly positively correlated with NAWM volumes, whereas global memory was significantly positively correlated with overall brain parenchyma (r = 0.38, p = 0.04). We conclude that quantitative assessment of MR examinations in survivors of childhood cancer treated with cranial irradiation reveal that loss of NAWM is associated with decreased intellectual and attentional deficits, whereas overall parenchyma loss, as reflected by increased CSF and decreased white matter, is associated with memory-related deficits.

Reddick, Wilburn E.; White, Holly A.; Glass, John O.; Mulhern, Raymond K.

2002-04-01

403

Changes in nasal airflow and heat transfer correlate with symptom improvement after surgery for nasal obstruction  

PubMed Central

Surgeries to correct nasal airway obstruction (NAO) often have less than desirable outcomes, partly due to the absence of an objective tool to select the most appropriate surgical approach for each patient. Computational fluid dynamics (CFD) models can be used to investigate nasal airflow, but variables need to be identified that can detect surgical changes and correlate with patient symptoms. CFD models were constructed from pre- and post-surgery computed tomography scans for 10 NAO patients showing no evidence of nasal cycling. Steady-state inspiratory airflow, nasal resistance, wall shear stress, and heat flux were computed for the main nasal cavity from nostrils to posterior nasal septum both bilaterally and unilaterally. Paired t-tests indicated that all CFD variables were significantly changed by surgery when calculated on the most obstructed side, and that airflow, nasal resistance, and heat flux were significantly changed bilaterally as well. Moderate linear correlations with patient-reported symptoms were found for airflow, heat flux, unilateral allocation of airflow, and unilateral nasal resistance as a fraction of bilateral nasal resistance when calculated on the most obstructed nasal side, suggesting that these variables may be useful for evaluating the efficacy of nasal surgery objectively. Similarity in the strengths of these correlations suggests that patient-reported symptoms may represent a constellation of effects and that these variables should be tracked concurrently during future virtual surgery planning. PMID:24063885

Kimbell, J.S.; Frank, D.O.; Laud, Purushottam; Garcia, G.J.M.; Rhee, J.S.

2014-01-01

404

Is there a correlation between intravaginal ejaculatory latency time and enuresis? An exploratory study  

PubMed Central

Introduction Premature ejaculation (PE) is the most common male sexual dysfunction. Monosymptomatic enuresis (ME) is nocturnal bed wetting, without any daytime symptoms. Recent clinical studies report an association between lifelong PE and ME. The purpose of this study was to compare the intravaginal ejaculatory time (IELT) between lifelong PE in men with and without ME. The goal was to determine if there is an association between the severity of ME and of IELT. Material and methods A total of 137 men with lifelong PE were included in this study. Subjects were asked if they had childhood ME. The characteristics and mean IELTs of patients with and without ME were compared using the student's t–test, and the correlation between severity of ME and IELT was assessed with trend test. Results Of the 137 lifelong PE patients, 57 reported ME. There was a strong negative correlation in patients with ME between the severity of enuresis and IELT, with IELT being shorter in patients with severe ME. Conclusions A strong correlation between IELT and the severity of ME suggests a common underlying mechanism. Further studies are required to confirm these findings and elucidate the exact pathophysiology. PMID:24982787

Serefoglu, Ege Can; Karacay, Safak; Ozdemir, Ahmet Tunc; Kalkan, Mehmet; Yencilek, Faruk

2014-01-01

405

SAW correlator spread spectrum receiver  

DOEpatents

A surface acoustic wave (SAW) correlator spread-spectrum (SS) receiver is disclosed which utilizes a first demodulation stage with a chip length n and a second demodulation stage with a chip length m to decode a transmitted SS signal having a code length l=n.times.m which can be very long (e.g. up to 2000 chips or more). The first demodulation stage utilizes a pair of SAW correlators which demodulate the SS signal to generate an appropriate code sequence at an intermediate frequency which can then be fed into the second demodulation stage which can be formed from another SAW correlator, or by a digital correlator. A compound SAW correlator comprising two input transducers and a single output transducer is also disclosed which can be used to form the SAW correlator SS receiver, or for use in processing long code length signals.

Brocato, Robert W

2014-04-01

406

Quantum correlations in spin models  

SciTech Connect

Bell nonlocality, entanglement and nonclassical correlations are different aspects of quantum correlations for a given state. There are many methods to measure nonclassical correlations. In this paper, nonclassical correlations in two-qubit spin models are measured by the use of measurement-induced disturbance (MID) [S. Luo, Phys. Rev. A 77 (2008) 022301] and geometric measure of quantum discord (GQD) [B. Dakic, V. Vedral, C. Brukner, Phys. Rev. Lett. 105 (2010) 190502]. Their dependences on external magnetic field, spin-spin coupling, and the Dzyaloshinskii-Moriya (DM) interaction are presented in detail. We also compare Bell nonlocality, entanglement measured by concurrence, MID and GQD and illustrate their different characteristics. - Highlights: > Various quantum correlations in spin models are investigated. > Nonclassical correlations are measured by measurement-induced disturbance and Geometric measure of quantum discord. > Also, we investigate Bell nonlocality and concurrence. > We compare these quantum quantities and illustrate their different characteristics.

Zhang Guofeng, E-mail: gf1978zhang@buaa.edu.cn [Department of Physics, School of Physics and Nuclear Energy Engineering, Beihang University, Xueyuan Road No. 37, Beijing 100191 (China); Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Fan Heng; Ji Ailing [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Jiang Zhaotan [Department of Physics, Beijing Institute of Technology, Beijing 100081 (China); Abliz, Ahmad [School of Mathematics, Physics and Informatics, Xinjiang Normal University, Urumchi 830054 (China); Liu Wuming [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

2011-10-15

407

Spectroscopy with Multichannel Correlation Radiometers  

E-print Network

Correlation radiometers make true differential measurements in power with high accuracy and small systematic errors. This receiver architecture has been used in radio astronomy for measurements of continuum radiation for over 50 years; this article examines spectroscopy over broad bandwidths using correlation techniques. After general discussions of correlation and the choice of hybrid phase, experimental results from tests with a simple laboratory multi-channel correlation radiometer are shown. Analysis of the effect of the input hybrid's phase shows that a 90 degree hybrid is likely to be the best general choice for radio astronomy, depending on its amplitude match and phase flatness with frequency. The laboratory results verify that the combination of the correlation architecture and an analog lag correlator is an excellent method for spectroscopy over very wide bandwidths.

A. I. Harris

2005-04-20

408

Correlational effect size benchmarks.  

PubMed

Effect size information is essential for the scientific enterprise and plays an increasingly central role in the scientific process. We extracted 147,328 correlations and developed a hierarchical taxonomy of variables reported in Journal of Applied Psychology and Personnel Psychology from 1980 to 2010 to produce empirical effect size benchmarks at the omnibus level, for 20 common research domains, and for an even finer grained level of generality. Results indicate that the usual interpretation and classification of effect sizes as small, medium, and large bear almost no resemblance to findings in the field, because distributions of effect sizes exhibit tertile partitions at values approximately one-half to one-third those intuited by Cohen (1988). Our results offer information that can be used for research planning and design purposes, such as producing better informed non-nil hypotheses and estimating statistical power and planning sample size accordingly. We also offer information useful for understanding the relative importance of the effect sizes found in a particular study in relationship to others and which research domains have advanced more or less, given that larger effect sizes indicate a better understanding of a phenomenon. Also, our study offers information about research domains for which the investigation of moderating effects may be more fruitful and provide information that is likely to facilitate the implementation of Bayesian analysis. Finally, our study offers information that practitioners can use to evaluate the relative effectiveness of various types of interventions. (PsycINFO Database Record (c) 2015 APA, all rights reserved). PMID:25314367

Bosco, Frank A; Aguinis, Herman; Singh, Kulraj; Field, James G; Pierce, Charles A

2015-03-01

409

Medial thalamic 18-FDG uptake following inescapable shock correlates with subsequent learned helpless behavior  

SciTech Connect

The learned helplessness paradigm has been repeatedly shown to correlate with neurobiological aspects of depression in humans. In this model, rodents are exposed inescapable foot-shock in order to reveal susceptibility to escape deficit, defined as 'learned helplessness' (LH). Few methods are available to probe the neurobiological aspects underlying the differences in susceptibility in the living animal, thus far being limited to studies examining regional neurochemical changes with microdialysis. With the widespread implementation of small animal neuroimaging methods, including positron emission tomography (PET), it is now possible to explore the living brain on a systems level to define regional changes that may correlate with vulnerability to stress. In this study, 12 wild type Sprague-Dawley rats were exposed to 40 minutes of inescapable foot-shock followed by metabolic imaging using 2-deoxy-2[{sup 18}F]fluoro-D-glucose (18-FDG) 1 hour later. The escape test was performed on these rats 48 hours later (to accommodate radiotracer decay), where they were given the opportunity to press a lever to shut off the shock. A region of interest (ROI) analysis was used to investigate potential correlations (Pearson Regression Coefficients) between regional 18-FDG uptake following inescapable shock and subsequent learned helpless behavior (time to finish the test; number of successful lever presses within 20 seconds of shock onset). ROI analysis revealed a significant positive correlation between time to finish and 18-FDG uptake, and a negative correlation between lever presses and uptake, in the medial thalamic area (p=0.033, p=0.036). This ROI included the paraventricular thalamus, mediodorsal thalamus, and the habenula. In an effort to account for possible spillover artifact, the posterior thalamic area (including ventral medial and lateral portions) was also evaluated but did not reveal significant correlations (p=0.870, p=0.897). No other significant correlations were found in additional regions analyzed including the nucleus accumbens, caudate putamen, substantia nigra, and amygdala. These data suggest that medial thalamic 18-FDG uptake during inescapable shock may contribute to subsequent escape deficits, and are not confounded by shock effects per se, since all animals received the same treatment prior to scanning. We have previously explored 18-FDG differences following the escape test session which also showed hyperactivity in the medial thalamus of learned helpless animals compared to non-learned helpless, and included additional cortical-limbic changes. Given the neuroanatomical connections between the medial thalamus (and habenula) with the prefrontal cortex and monoaminergic brain stem, one possible speculation is that abnormal neuronal activity in these areas during stress may set in motion circuitry changes that correlate with learned helpless behavior.

Mirrione,M.M.; Mirrione, M.M.; Schulz, D.; Dewey, S.L.; Henn, F.A.

2009-12-06

410

Image correlation and sampling study  

NASA Technical Reports Server (NTRS)

The development of analytical approaches for solving image correlation and image sampling of multispectral data is discussed. Relevant multispectral image statistics which are applicable to image correlation and sampling are identified. The general image statistics include intensity mean, variance, amplitude histogram, power spectral density function, and autocorrelation function. The translation problem associated with digital image registration and the analytical means for comparing commonly used correlation techniques are considered. General expressions for determining the reconstruction error for specific image sampling strategies are developed.

Popp, D. J.; Mccormack, D. S.; Sedwick, J. L.

1972-01-01

411

Electronic correlation strength of Pu  

NASA Astrophysics Data System (ADS)

An electronic quantity, the correlation strength, is defined as a necessary step for understanding the properties and trends in strongly correlated electronic materials. As a test case, this is applied to the different phases of elemental Pu. Within the GW approximation we have surprisingly found a “universal” scaling relationship, where the f-electron bandwidth reduction due to correlation effects is shown to depend only on the local density approximation bandwidth and is otherwise independent of crystal structure and lattice constant.

Svane, A.; Albers, R. C.; Christensen, N. E.; van Schilfgaarde, M.; Chantis, A. N.; Zhu, Jian-Xin

2013-01-01

412

The Interpretation of Correlation Data.  

E-print Network

and offspring may be the case as a consequence of genetic variability. On the other hand, "modifiability" may be a factor determining the value of the correlation. Babcock and Clausen7 state that Pearl and Surface show a lack of correlation between mothers... of breeding must be adopted that will discount at their proper values the influences of modifiability and genetic variability attending segregation. Hayes and Garbers discuss the early work in correlation of plant characters and yield, particularly...

Conner, A. B. (Arthur Benjamin)

1923-01-01

413

Interpreting Near-side Correlations  

E-print Network

Recent data from heavy ion collisions at RHIC show strong near-side correlations extending over several units of rapidity. This ridge-like correlation exhibits an abrupt onset with collision centrality. In this talk, I argue that the centrality and beam-energy dependence of these near-angle correlations could provide access to information about the Quark Gluon Plasma phase boundary and the Equation of State of nuclear matter. A beam-energy-scan at RHIC will better reveal the true source of these correlations and should be a high priority at RHIC.

Paul Sorensen

2008-11-18

414

Producing and Detecting Correlated atoms  

E-print Network

We discuss experiments to produce and detect atom correlations in a degenerate or nearly degenerate gas of neutral atoms. First we treat the atomic analog of the celebrated Hanbury Brown Twiss experiment, in which atom correlations result simply from interference effects without any atom interactions.We have performed this experiment for both bosons and fermions. Next we show how atom interactions produce correlated atoms using the atomic analog of spontaneous four-wavemixing. Finally, we briefly mention experiments on a one dimensional gas on an atom chip in which correlation effects due to both interference and interactions have been observed.

Christoph I. Westbrook; Martijn Schellekens; Aurélien Perrin; Valentina Krachmalnicoff; Jose Carlos Viana Gomes; Jean-Baptiste Trebbia; Jérôme Estève; Hong Chang; Isabelle Bouchoule; Denis Boiron; Alain Aspect; Tom Jeltes; John McNamara; Wim Hogervorst; Wim Vassen

2006-09-04

415

Three-Particle Azimuthal Correlations  

E-print Network

Two-particle azimuthal correlations reveal broadened and softened away-side correlations. Several different physics mechanisms are possible: large angle gluon radiation, deflected jets, and conical flow or Cerenkov radiation. Three-particle correlations are investigated to try to discriminate these mechanisms. We present results on 3-particle azimuthal correlations between a trigger particle of 3

Jason Glyndwr Ulery

2006-09-29

416

Correlation between eminence steepness and condyle disc movements in temporomandibular joints with internal derangements on magnetic resonance imaging.  

PubMed

A steep articular eminence is reported to be a predisposing factor for the development of disc displacement. The purpose of this study was to evaluate the biomechanics of the temporomandibular joint (TMJ) in internal derangements and, additionally, to investigate whether a relationship exists between the steepness of the articular eminence and disc displacement, with (DDR) and without reduction (DDWR). The material consisted of the sagittal TMJ magnetic resonance images (MRIs) of 39 joints (26 DDR and 13 DDWR). Sagittal and coronal TMJ MRIs were obtained at maximum inter-cuspation and in the maximum mouth-opening position. The steepness of the articular eminence, disc, and condyle rotation, and condyle translation were investigated. A Student's t-test was performed and correlation coefficients calculated. The results revealed an increase in disc rotation in the DDR group and in condyle translation in the DDWR group (P < 0.01). Condyle rotation and the steepness of the articular eminence were similar in both groups. Disc rotation was positively correlated with condyle rotation and negatively correlated with condyle translation in the DDR group (P < 0.05, r = 0.44). Condyle translation was positively correlated with steepness of the articular eminence in the DDWR group (P < 0.01, r = 0.74). There was no correlation between movements of the disc-condyle assembly and the steepness of the articular eminence in the DDR group. Nevertheless, a relationship between condyle translation and the steepness of the articular eminence was found in the DDWR subjects. PMID:11668877

Gökalp, H; Türkkahraman, H; Bzeizi, N

2001-10-01

417

PostPost--CorrelationCorrelation RFIRFI--ExcisionExcision  

E-print Network

The Problem Existing radio telescope systems do not routinelyExisting radio telescope systems do not routinely by the radio telescopes or their supporting systems.telescopes or their supporting systems. As a userPostPost--CorrelationCorrelation RFIRFI--ExcisionExcision at Low Radio Frequenciesat Low Radio

Ellingson, Steven W.

418

Detecting protein atom correlations using correlation of probability of recurrence.  

PubMed

The dynamic cross-correlation Map(DCCM) technique has been used extensively to study protein dynamics. In this work, we introduce the use of the method of correlation of probability of recurrence (CPR) as a complementary method to detect correlations between protein residue atoms. Time series of the distances of the C? atoms of the ?-lactamase inhibitory protein (BLIP) from a reference position are analyzed using CPR and mutual information (MI). The results are compared to those provided by DCCM. In comparison to MI, CPR is found to detect more of the correlations present in DCCM. It is also able to detect a small number of significant correlations between distant residues that are not detected by DCCM. PMID:24723469

Fataftah, Hiba; Karain, Wael

2014-09-01

419

City-City Correlations to Introduce Galaxy-Galaxy Correlations  

NASA Astrophysics Data System (ADS)

The large-scale structure of the Universe, vividly displayed by the spatial distribution of galaxies, is characterised quanti- tatively by the two-point galaxy-galaxy correlation function. But the meaning of the correlation function is somewhat abstract because it does not have a ready analogy. This work computes the two-dimensional, two-point city-city correlation function for three populous regions of the United States, demonstrating that the city-city correlation function is analogous to the galaxy-galaxy correlation function determined from Sloan Digital Sky Survey data. City radii are analogous to galaxy cluster radii, and city-to-city distances are analogous to distances between galaxy clusters. Part of this work has been adapted for a lab suitable for non-experts.

Smith, D. M.

2014-07-01

420

Correlation of Palatal Rugoscopy with Gender, Palatal Vault Height and ABO Blood Groups in Three Different Indian Populations  

PubMed Central

Background: Palatal rugae (PR) are asymmetrical irregular elevations, recorded during maxillary cast fabrication, that can be used for identification purpose if previous comparative sources are available. Aim: This study investigated uniqueness of PR patterns in relation to gender, palatal vault forms, and ABO blood groups in three (North-East [N-E], Northern and Western) populations of India. Subjects and Methods: The study was conducted on randomly selected 90 students, 30 from each sub population. Design - The palatal vault was recorded as Types I, II, and III. The maxillary casts were analyzed for each subject. The blood group of each subject was also recorded. Pearson's correlation coefficient tests were performed on cross-tabulations to evaluate significant relationship among different variables. Results: The PR number was more among females with an insignificant correlation among gender and mean rugae size on both sides. Types I and II hard palate vaults were seen associated with straight forwardly directed PR pattern, while Type III with curved forwardly directed PR. On the right side, straight rugae shape was most common type. On the left side, straight rugae shape was most common in Northern population while in N-E and Western populations curved rugae was the dominating type. A highly significant correlation was found between ABO blood groups and different PR patterns. Conclusions: PR possesses unique characteristics and can be used along with palatal vault forms as well as ABO blood groups for racial and individualistic soft tissue oral print in forensic cases. PMID:25328791

Verma, KG; Verma, P; Bansal, N; Basavaraju, S; Sachdeva, SK; Khosa, R

2014-01-01

421

Correlation of general anxiety and dental anxiety in children aged 3 to 5 years: A clinical survey  

PubMed Central

Background: The aim of this study was to determine the prevalence of dental anxiety in a group of children aged 3 to 5 years and to explore the relationships between dental anxiety and general fearful nature of the child. Materials & Methods: A total of 250 children were selected for the study after due selection via inclusion criteria. Pre-school anxiety scale by Spence and Rapee (1999) was used to assess the general fear of the child and was filled by the parent during the first visit. Venham’s anxiety scale was used to assess the dental anxiety which was seen during routine dental examination of the child on his first visit. Results: The results were statistically analyzed using Chi square test and Karl Pearson coefficient of correlation. Conclusion: It was concluded that 24% of children showed association between high level of dental anxiety and high level of general fear; 56% of children also exhibited high level of dental anxiety with moderate score of general fear and 20% of children exhibited positive correlation between low level of dental anxiety and fear. How to cite this article: Nigam AG, Marwah N, Goenka P, Chaudhry A. Correlation of general anxiety and dental anxiety in children aged 3 to 5 years: A clinical survey. J Int Oral Health 2013;5(6):18-24 . PMID:24453440

Nigam, Anant Gopal; Marwah, Nikhil; Goenka, Puneet; Chaudhry, Ajay

2013-01-01

422

HMG-CoA reductase expression in primary colorectal cancer correlates with favourable clinicopathological characteristics and an improved clinical outcome  

PubMed Central

Background An association between tumor-specific HMG-CoA reductase (HMGCR) expression and good prognosis has previously been demonstrated in breast and ovarian cancer. In this study, the expression, clinicopathological correlates and prognostic value of HMGCR expression in colorectal cancer was examined. Findings Immunohistochemical expression of HMGCR was assessed in tissue microarrays with primary tumours from 557 incident cases of colorectal cancer in the Malmö Diet and Cancer Study. Pearson’s Chi Square test was applied to explore the associations between HMGCR expression and clinicopathological factors and other investigative biomarkers. Kaplan Meier analysis and Cox proportional hazards modeling were used to assess the relationship between HMGCR expression and cancer-specific survival (CSS) according to negative vs positive HMGCR expression. A total number of 535 (96.0%) tumours were suitable for analysis, of which 61 (11.4%) were HMGCR negative. Positive cytoplasmic HMGCR expression was associated with distant metastasis-free disease at diagnosis (p = 0.002), lack of vascular invasion (p = 0.043), microsatellite-instability (p = 0.033), expression of cyclin D1 (p = <0.001) and p21 (p = <0.001). Positive HMGCR expression was significantly associated with a prolonged CSS in unadjusted Cox regression analysis in the entire cohort (HR = 1.79; 95% CI 1.20-2.66) and in Stage III-IV disease (HR = 1.71; 95% CI 1.09-2.68), but not after adjustment for established clinicopathological parameters. Conclusions Findings from this prospective cohort study demonstrate that HMGCR is differentially expressed in colorectal cancer and that positive expression is associated with favourable tumour characteristics and a prolonged survival in unadjusted analysis. The utility of HMGCR as a predictor of response to neoadjuvant or adjuvant statin treatment in colorectal cancer merits further study. Virtual slides The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2115647072103464. PMID:24708688

2014-01-01

423

Clinical Correlates to Laboratory Measures for use in Non-Contact Anterior Cruciate Ligament Injury Risk Prediction Algorithm  

PubMed Central

Background Prospective measures of high knee abduction moment during landing identify female athletes at high risk for non-contact anterior cruciate ligament injury. Biomechanical laboratory measurements predict high knee abduction moment landing mechanics with high sensitivity (85%) and specificity (93%). The purpose of this study was to identify correlates to laboratory-based predictors of high knee abduction moment for use in a clinic-based anterior cruciate ligament injury risk prediction algorithm. The hypothesis was that clinically obtainable correlates derived from the highly predictive laboratory-based models would demonstrate high accuracy to determine high knee abduction moment status. Methods Female basketball and soccer players (N=744) were tested for anthropometrics, strength and landing biomechanics. Pearson correlation was used to identify clinically feasible correlates and logistic regression to obtain optimal models for high knee abduction moment prediction. Findings Clinical correlates to laboratory-based measures were identified and predicted high knee abduction moment status with 73% sensitivity and 70% specificity. The clinic-based prediction algorithm, including (Odds Ratio: 95% confidence interval) knee valgus motion (1.43:1.30–1.59 cm), knee flexion range of motion (.98:0.96–1.01 deg), body mass (1.04:1.02–1.06 kg), tibia length (1.38:1.25–1.52 cm) and quadriceps to hamstring ratio (1.70:1.06–2.70) predicted high knee abduction moment status with C statistic 0.81. Interpretation The combined correlates of increased knee valgus motion, knee flexion range of motion, body mass, tibia length and quadriceps to hamstrings ratio predict high knee abduction moment status in female athletes with high sensitivity and specificity. PMID:20554101

Myer, Gregory D.; Ford, Kevin R.; Khoury, Jane; Succop, Paul; Hewett, Timothy E.

2010-01-01

424

OA01.25.The first direct experimental evidence correlating ayurveda based tridosha prakriti, with western constitutional psychology somatotypes  

PubMed Central

Purpose: Ayurveda is one of the most ancient systems of medical health care. The basic principles, diagnosis of the diseases and their treatment are based on individual prakriti (constitutional type). Ayurveda further classifies the prakriti of an individual on the basis of a set of psychosomatic attributes of personality, depending on whether this individual belongs to Vata, Pitta, or Kapha prakriti, or any combination of them (Patwardhan et al., 2005). The appropriate prakriti assessment is done by several means including questionnaires (Rastogi, 2012; Shilpa and Venkatesha-Murthy, 2011). We aimed to obtain experimental evidence correlating Ayurveda based tridosha-prakriti with western constitutional psychology somatotypes (Rizzo-Sierra, 2011). Method: We employed our Tridosha-prakriti questionnaire (Ramakrishna and Nagendra, 2012), and compared its results with a set of body composition parameters: Height, body weight, body mass index (BMI), muscle mass, fat mass, and fat percentage in normal healthy volunteers (25 males and 25 females, mean age was 26 (± 4) and 25 (± 6) years respectively). Moreover, two-tailed Pearson's correlations were investigated to match the extreme prakriti types with the western constitutional psychology somatotypes, through the mentioned body composition measures. Result: Significant negative correlations were observed between the percentage of Vata attributes as per the questionnaire in the individuals and their BMI, body weight and fat mass respectively (p<0.05). Similarly, there was a significant positive correlation between the percentage of Pitta attributes with the height, body weight, and muscle mass respectively. Also, a significant positive correlation was observed between the percentage of Kapha attributes with fat mass and fat percentage, along with a negative correlation with height. Conclusion: We provide evidence-linking Ayurveda to modern constitutional psychology. In this way, a concept such as prakriti is suggested to lie behind the body mass composition of an individual, and deserves attention within the scientific community.

Metri, Kashinath G; Bhargav, Hemant; Ramarao, Nagendra Hongasandra; Rizzo-Sierra; Basavakatti, Ramakrishna R

2012-01-01

425

Studies of Diffuse Interstellar Bands V. Pairwise Correlations of Eight Strong DIBs and Neutral Hydrogen, Molecular Hydrogen, and Color Excess  

NASA Astrophysics Data System (ADS)

We establish correlations between equivalent widths of eight diffuse interstellar bands (DIBs), and examine their correlations with atomic hydrogen, molecular hydrogen, and E B-V . The DIBs are centered at ?? 5780.5, 6204.5, 6283.8, 6196.0, 6613.6, 5705.1, 5797.1, and 5487.7, in decreasing order of Pearson's correlation coefficient with N(H) (here defined as the column density of neutral hydrogen), ranging from 0.96 to 0.82. We find the equivalent width (EW) of ?5780.5 is better correlated with column densities of H than with E B-V or H2, confirming earlier results based on smaller data sets. We show that the same is true for six of the seven other DIBs presented here. Despite this similarity, the eight strong DIBs chosen are not correlated well enough with each other to suggest they come from the same carrier. We further conclude that these eight DIBs are more likely to be associated with H than with H2, and hence are not preferentially located in the densest, most UV shielded parts of interstellar clouds. We suggest that they arise from different molecules found in diffuse H regions with very little H2 (molecular fraction f < 0.01). Of the 133 stars with available data in our study, there are three with significantly weaker ?5780.5 than our mean H-?5780.5 relationship, all of which are in regions of high radiation fields, as previously noted by Herbig. The correlations will be useful in deriving interstellar parameters when direct methods are not available. For instance, with care, the value of N(H) can be derived from W ?(5780.5).

Friedman, Scott D.; York, Donald G.; McCall, Benjamin J.; Dahlstrom, Julie; Sonnentrucker, Paule; Welty, Daniel E.; Drosback, Meredith M.; Hobbs, L. M.; Rachford, Brian L.; Snow, Theodore P.

2011-01-01

426

STUDIES OF DIFFUSE INTERSTELLAR BANDS V. PAIRWISE CORRELATIONS OF EIGHT STRONG DIBs AND NEUTRAL HYDROGEN, MOLECULAR HYDROGEN, AND COLOR EXCESS  

SciTech Connect

We establish correlations between equivalent widths of eight diffuse interstellar bands (DIBs), and examine their correlations with atomic hydrogen, molecular hydrogen, and E{sub B-V}. The DIBs are centered at {lambda}{lambda} 5780.5, 6204.5, 6283.8, 6196.0, 6613.6, 5705.1, 5797.1, and 5487.7, in decreasing order of Pearson's correlation coefficient with N(H) (here defined as the column density of neutral hydrogen), ranging from 0.96 to 0.82. We find the equivalent width (EW) of {lambda}5780.5 is better correlated with column densities of H than with E{sub B-V} or H{sub 2}, confirming earlier results based on smaller data sets. We show that the same is true for six of the seven other DIBs presented here. Despite this similarity, the eight strong DIBs chosen are not correlated well enough with each other to suggest they come from the same carrier. We further conclude that these eight DIBs are more likely to be associated with H than with H{sub 2}, and hence are not preferentially located in the densest, most UV shielded parts of interstellar clouds. We suggest that they arise from different molecules found in diffuse H regions with very little H{sub 2} (molecular fraction f < 0.01). Of the 133 stars with available data in our study, there are three with significantly weaker {lambda}5780.5 than our mean H-{lambda}5780.5 relationship, all of which are in regions of high radiation fields, as previously noted by Herbig. The correlations will be useful in deriving interstellar parameters when direct methods are not available. For instance, with care, the value of N(H) can be derived from W{sub {lambda}}(5780.5).

Friedman, Scott D.; Sonnentrucker, Paule [Space Telescope Science Institute, Baltimore, MD 21218 (United States); York, Donald G.; Hobbs, L. M. [Department of Astronomy and Astrophysics and the Enrico Fermi Institute, University of Chicago, Chicago, IL (United States); McCall, Benjamin J. [Departments of Chemistry, Astronomy, and Physics, University of Illinois at Urbana-Champaign, IL (United States); Dahlstrom, Julie [Department of Physics and Astronomy, Carthage College, Kenosha, WI (United States); Welty, Daniel E. [Department of Astronomy, University of Illinois at Urbana-Champaign, IL (United States); Drosback, Meredith M. [Department of Astronomy, University of Virginia, Charlottesville, VA (United States); Rachford, Brian L. [Department of Physics, Embry-Riddle Aeronautical University, Prescott, AZ (United States); Snow, Theodore P., E-mail: friedman@stsci.edu [Center for Astrophysics and Space Astronomy, University of Colorado, Boulder, CO (United States)

2011-01-20

427

Reference values, intertest correlations, and test-retest repeatability of selected tear film tests in healthy cats.  

PubMed

Objective-To determine reference values, intertest correlations, and test-retest repeatability of Schirmer tear test 1 (STT-1), phenol red thread test (PRTT), tear film breakup time (TFBUT), tear osmolarity, and meibometry in healthy cats. Design-Evaluation study. Animals-135 healthy domestic cats aged 0.5 to 12.8 years. Procedures-Each test was performed once in 120 cats and repeated in 40. Pearson correlation was used to assess correlation among tests. Intraclass correlation coefficients (ICCs) and 95% limits of agreement (LOA) were used to evaluate test-retest repeatability. Results-Median (95% central range) values were 18 mm/min (9 to 34 mm/min) for STT-1, 29 mm/15 s (15 to 37 mm/15 s) for PRTT, 12.4 seconds (9.1 to 17.7 seconds) for TFBUT, 322 mOsm/L (297 to 364 mOsm/L) for osmolarity, and 32 meibometry units (MU; 11 to 114 MU) for peak meibometry value. The STT-1 and PRTT values were positively correlated. Age was weakly associated with TFBUT and osmolarity. Meibometry measurements were higher for strips that contacted the tear film (285 MU) than for those that touched the eyelid margin only (32 MU). All ICCs were < 0.75, and 95% LOA were wide. Conclusions and Clinical Relevance-Tear deficiency should be suspected in cats with STT-1 < 9 mm/min, PRTT < 15 mm/15 s, or TFBUT < 9 to 10 seconds. Generally poor correlation among tests suggested that thorough tear film analysis requires performance of multiple tests in concert. Relatively poor test-retest repeatability should be considered when repeated tests are used to monitor tear film dysfunction and response to treatment. PMID:25632817

Sebbag, Lionel; Kass, Philip H; Maggs, David J

2015-02-15

428

Melatonin and its correlation with testosterone in polycystic ovarian syndrome  

PubMed Central

CONTEXT: Polycystic ovarian syndrome (PCOS) is considered to be the most common endocrine disorder affecting women. Melatonin, a small lipophilic indoleamine, and reproductive hormones may be interrelated. Melatonin influences sex steroid production at different stages of ovarian follicular maturation as melatonin receptors have been demonstrated at multiple sites in ovary and in intrafollicular fluid. It plays role as an antioxidant and free radical scavanger which protects follicles from oxidative stress, rescuing them from atresia, leading to complete follicular maturation and ovulation. AIMS: To study the role of melatonin in PCOS and to investigate its correlation with testosterone in patients suffering from PCOS. SETTINGS AND DESIGN: A total of 50 women with PCOS (Rotterdam criteria, 2003) and 50 age and weight matched healthy controls were selected and serum melatonin estimation was done in both the groups and correlated with serum total testosterone levels. MATERIALS AND METHODS: In a case-control study, detailed history, clinical examination and hormonal evaluation [basal levels of leutinizing hormone, follicle-stimulating hormone, thyroid-stimulating hormone, prolactin, insulin, total testosterone, progesterone and melatonin] were carried out in all the participants including both cases and controls. For melatonin estimation, blood samples were collected between 12:00 am and 04:00 am on day 2nd of menstrual cycle and analyzed by using commercially available enzyme-linked immunosorbent assay kit. STATISTICAL ANALYSIS: Student's t-test was used to compare the significant difference in mean values between cases and control groups. Chi-square test was used to test the significant association between the qualitative variables. Linear correlation coefficient and regression analysis were done to see the amount and direction of relationship between quantitative variables. RESULTS: The mean melatonin level was observed to be significantly increased in patients (63.27 ± 10.97 pg/mL) than in controls (32.51 ± 7.55 pg/mL). Melatonin was found to be raised in all the cases of PCOS (above cut-off value of ?45 pg/mL, P < 0.001). Total testosterone level was also raised in 72% of patients. Melatonin levels were found to be positively associated with increased testosterone (P < 0.001). In regression analysis using melatonin as dependent variable and testosterone as an independent variable, the value of R2 ? 100 (percent variation) was found to be 72.1%. CONCLUSIONS: Women with PCOS have significantly raised serum melatonin levels and hyperandrogenemia along with increased number of atretic follicles. Further studies are required to establish a definite role of melatonin in PCOS cases with disturbed hormonal milieu. This could open up the way for therapeutic role of melatonin in treatment of patients suffering from PCOS. PMID:24672165

Jain, Priyanka; Jain, Madhu; Haldar, Chandana; Singh, Tej Ball; Jain, Shuchi

2013-01-01

429

The relationship between English language learning strategies and proficiency of pre-university students: A study case of UMS  

NASA Astrophysics Data System (ADS)

This paper seeks to investigate the relationship between language learning strategies and proficiency in English. Fifty-six pre-university students (22 males, 34 females) of University Malaysia Sabah participated in this study. Oxford's Strategy Inventory for Language Learning (SILL) self-report questionnaire was adopted to identify the students' language learning strategies, whereas their proficiencies were judged based on their Malaysian University English Test (MUET) Results. Pearson's correlation coefficient, Spearman's rank correlation coefficient and the t-test were utilized to make statistical interpretation about the relationship. The knowledge obtained from this study will be helpful for future studies on how to improve the quality of learning and proficiency in English.

Kiram, Johannah Jamalul; Sulaiman, Jumat; Swanto, Suyansah; Din, Wardatul Akmam

2014-07-01

430

Illusory correlations in graphological inference  

Microsoft Academic Search

The authors investigate the illusory correlation phenomenon as a possible contributor to the persistence of graphology's use to predict personality. Participants unfamiliar with graphology inspected handwriting samples paired with fabricated personality profiles. In Experiment 1, handwriting samples and person- ality profiles were randomly paired. In Experiment 2, discernible correlations near unity were set between targeted handwriting-feature-personality-trait pairs in a congruent

Roy N. King; Derek J. Koehler

2000-01-01

431

Illusory Correlations in Graphological Inference  

Microsoft Academic Search

The authors investigate the illusory correlation phenomenon as a possible contributor to the persistence of graphology's use to predict personality. Participants unfamiliar with graphology inspected handwriting samples paired with fabricated personality profiles. In Experiment 1, handwriting samples and personality profiles were randomly paired. In Experiment 2, discernible correlations near unity were set between targeted handwriting-feature–personality-trait pairs in a congruent or

Roy N. King; Derek J. Koehler

2000-01-01

432

Correlation filters for orientation estimation  

NASA Technical Reports Server (NTRS)

An important task in many vision applications is that of rapidly estimating the orientation of an object with respect to some frame of reference. Because of their speed and parallel processing capabilities, optical correlators should prove valuable in this application. This paper considers two algorithms for object orientation estimation based on optical correlations and presents some initial simulation results.

Kumar, B. V. K. Vijaya; Lee, Andrew J.; Connelly, James M.

1988-01-01

433

Magnitude correlations in global seismicity.  

PubMed

By employing natural time analysis, we analyze the worldwide seismicity and study the existence of correlations between earthquake magnitudes. We find that global seismicity exhibits nontrivial magnitude correlations for earthquake magnitudes greater than M(w) 6.5. PMID:21929043

Sarlis, N V

2011-08-01

434

Measuring correlations in symbol sequences  

Microsoft Academic Search

The paper is devoted to relations between correlation functions and mutual information. It is shown that, in sequences over an alphabet of ? symbols, statistical dependences are measured by (? ? 1)2 independent parameters. However, not all of them can be determined by autocorrelation functions. Appropriate sets of correlation functions (including crosscorrelations) are introduced, which allow the detection of all

Hanspeter Herzel; Ivo Große

1995-01-01

435

Personality Correlates of Polydrug Abuse.  

ERIC Educational Resources Information Center

Although the personality correlates of heroin addiction, LSD use, and marijuana smoking have been frequently investigated, relatively few data are available to describe the personality or lifestyle variables correlated with the pattern of polydrug abuse. In an attempt to gather such information, 17 polydrug users, selected from a group of 224…

Kilpatrick, Dean G.; And Others

436

Polarization correlations of Dirac particles  

SciTech Connect

We calculate the polarization correlation function in the Einstein-Podolsky-Rosen-type experiments with relativistic spin-1/2 particles. This function depends monotonically on the particle momenta. Moreover, we also show that the polarization correlation function violates the Clauser-Horn-Shimony-Holt inequality and the degree of this violation can depend on the particle momenta and the motion of observers.

Caban, Pawel; Dziegielewska, Agnieszka; Karmazyn, Anna; Okrasa, Malgorzata [Department of Theoretical Physics, University of Lodz, Pomorska 149/153, 90-236 Lodz (Poland)

2010-03-15

437

Level Correlations in Integrable Systems  

Microsoft Academic Search

We derive a simple analytical expression for the level correlation function of an integrable system. It accounts for both the lack of correlations at smaller energy scales and for global rigidity (level number conservation) at larger scales. We apply our results to a rectangle with incommensurate sides and show that they are in excellent agreement with the limiting cases established

R. A. Serota

2002-01-01

438

Level correlations in integrable systems  

Microsoft Academic Search

We derive a simple analytical expression for the level correlation function of an integrable system. It accounts for both the lack of correlations at smaller energy scales and for global rigidity (level number conservation) at larger scales. We apply our results to a rectangle with incommensurate sides and show that they are in excellent agreement with the limiting cases established

R. A. Serota

2002-01-01

439

Correlation Weights in Multiple Regression  

ERIC Educational Resources Information Center

A general theory on the use of correlation weights in linear prediction has yet to be proposed. In this paper we take initial steps in developing such a theory by describing the conditions under which correlation weights perform well in population regression models. Using OLS weights as a comparison, we define cases in which the two weighting…

Waller, Niels G.; Jones, Jeff A.

2010-01-01

440

Drizzle correlations with giant nuclei  

Microsoft Academic Search

Giant nuclei (GN) concentrations (NGN) below RICO small cumulus clouds were substantially correlated with drizzle drop concentrations (Nd), especially at higher cloud altitudes. The NGN-Nd correlation coefficients (R) progressively increased with altitude whereas R for CCN concentrations with Nd were negative with mostly decreasing magnitudes at increasing altitudes. These results indicate that the positive influence of GN [or CCN with

James G. Hudson; Vandana Jha; Stephen Noble

2011-01-01

441

Correlates of Cognitive Student Outcomes.  

ERIC Educational Resources Information Center

A study of the correlates of cognitive achievement in Pennsylvania's Educational Quality Assessment Program was conducted by examining both individual (student level) and ecological (building level) correlations. Analyses were completed for grade levels 5, 8 and 11 for the 1985 state assessment. Twenty-four student derived condition variables or…

Kohr, Richard L.

442

Different Luminosity Correlation of GRBs  

NASA Astrophysics Data System (ADS)

We report our recent understanding about a tight correlation between relative spectral lag and luminosity (or redshift) for ?-ray bursts. The latest investigations indicate that the empirical correlations got from BATSE bursts also exist for Swift/BAT ones. The special luminosity-lag correlation is much similar to that of the luminosity with pulse number proposed by Schaefer (2003), but largely different from most of others ever discovered. Note that our newly built luminosity-lag correlation predicts that luminosity should evolve with cosmological redshift as L p ? (1 + z)2.4±0.7 that is excellently confirmed by Salvaterra et al. (2012) and Geng & Huang (2013). In addition, it is also surprisingly found that the luminosity-lag correlation can account for both long and short Swift/BAT bursts, which might be an evidence of the same radiation mechanism for diverse burst groups.

Zhang, Z. B.; Liu, H. C.; Jiang, L. Y.; Chen, D. Y.

2014-09-01

443

Correlation Between Haemoglobin Level and Electrocardiographic (ECG) Findings in Anaemia: A Cross-Sectional Study  

PubMed Central

Background: Anaemia affects the body by decreased oxygen (O2) carrying capacity of the blood. There is growing evidence that anaemia contributes to cardiac disease and death. It causes O2 supply – demand myocardial mismatch causing myocardial ischemia. There is diversity of opinion available in literature on reports of electrocardiographic (ECG) changes in anaemia. Aim: To study the ECG changes in anemic population and to correlate ECG changes seen with increasing severity of anaemia. Materials and Methods: In hundred anemic adults, haemoglobin level and resting ECG were recorded. They were grouped according to haemoglobin level. ECG findings and varying severity of haemoglobin (Hb) level of each group were correlated using Pearson ’s co-relation co-efficient and association was calculated using Chi-square test. Results: ECG changes in patients with Hb level of 0-5gm% showed ST segment depression in 50-75%, T wave changes in 29-50% and Left Ventricular Hypertrophy (LVH) in 25-30% of patients. Less percentage of patients with 5-7gm% Hb showed such changes, and patients with 7-8gm% Hb, showed no changes. As the Hb level decreased there was more percentage of patients having tachycardia and ECG changes. There was a strong negative correlation between Hb level and tachycardia and ECG changes. Conclusion: Diagnosing anaemia in critical care can be supported by ECG changes like ST depression, T wave changes, with/without associated QRS abnormalities to avoid misdiagnosis and also as dramatic clinical and ECG recovery can be achieved with anaemia correction. PMID:24959433

PK, Shashidhar; Herur, Anita; Chinagudi, Surekharani; Patil, Shailaja S; Ankad, Roopa B; Badami, Sukanya V

2014-01-01

444

Perception of better nasal patency correlates with increases in mucosal cooling after surgery for nasal obstruction  

PubMed Central

Objectives 1. Quantify mucosal cooling (i.e., heat loss) spatially in the nasal passages of nasal airway obstruction (NAO) patients before and after surgery using computational fluid dynamics (CFD). 2. Correlate mucosal cooling with patient-reported symptoms, as measured by the Nasal Obstruction Symptom Evaluation (NOSE) and a visual analog scale (VAS) for sensation of nasal airflow. Study Design Prospective Setting Academic tertiary medical center. Subjects and Methods Computed tomography (CT) scans and NOSE and VAS surveys were obtained from 10 patients before and after surgery to relieve NAO. Three-dimensional models of each patient’s nasal anatomy were used to run steady-state CFD simulations of airflow and heat transfer during inspiration. Heat loss across the nasal vestibule and the entire nasal cavity, and the surface area of mucosa exposed to heat fluxes > 50 W/m2 were compared pre- and post-operatively. Results After surgery, heat loss increased significantly on the pre-operative most obstructed side (p values < 0.0002). A larger surface area of nasal mucosa was exposed to heat fluxes > 50 W/m2 after surgery. The best correlation between patient-reported and CFD measures of nasal patency was obtained for NOSE against surface area in which heat fluxes > 50 W/m2 (Pearson r = ?0.76). Conclusion A significant post-operative increase in mucosal cooling correlates well with patients’ perception of better nasal patency after NAO surgery. CFD-derived heat fluxes may prove to be a valuable predictor of success in NAO surgery. PMID:24154749

Sullivan, Corbin D.; Garcia, Guilherme J. M.; Frank, Dennis O.; Kimbell, Julia S.; Rhee, John S.

2014-01-01

445

Correlation between vertical misfits and stresses over implants from castable frameworks made of different alloys.  

PubMed

This study aims to investigate a possible correlation between vertical misfits and the stresses transmitted to implants from one-piece casted frameworks fabricated with 3 different materials: commercially pure titanium, cobalt chromium alloy, and nickel chromium titanium alloy. Twelve frameworks simulating screw-retained prosthesis were fabricated from a master cast with 5 implants. Each framework was screwed (20 Ncm) over a metal cast and the vertical mesial and distal misfits were measured using an optical microscope. The stresses transmitted to the implants were measured in a third model by a quantitative photoelastic analysis. Stress and vertical misfit data were statistically analyzed by ANOVA and least significant difference tests and the correlation tests were performed using Pearson Correlation Test (? = 0.05). Mean and standard deviation values of vertical misfit and stress over implants are presented, respectively: commercially pure titanium (29.09 ± 13.24 ?m and 11.38 ± 9.23 kPa), cobalt chromium alloy (27.05 ± 10.30 ?m and 15.83 ± 9.30 kPa), nickel chromium titanium alloy (24.95 ± 11.14 ?m and 16.39 ± 9.51 kPa). There were no significant differences for vertical misfit (P = 0.285). Regarding the stress analysis, there were significant differences between commercially pure titanium, cobalt chromium alloy, and nickel chromium titanium alloy (P = 0.035), with the lowest values for the commercially pure titanium. It may be concluded that stress over implants was affected by different procedures and materials for framework production. PMID:25329843

Barbosa, Gustavo Augusto Seabra; Bernardes, Sérgio Rocha; de França, Danilo Gonzaga Bernardo; das Neves, Flávio Domingues; de Mattos, Maria da Glória Chiarello; Ribeiro, Ricardo Faria

2014-11-01

446

Evaluation of correlation between chemical dosimetry and subharmonic spectrum analysis to examine the acoustic cavitation.  

PubMed

Currently several therapeutic applications of ultrasound in cancer treatment are under progress which uses cavitation phenomena to deliver their effects. There are several methods to evaluate cavitation activity such as chemical dosimetry and measurement of subharmonic signals. In this study, the cavitation activity induced by the ultrasound irradiation on exposure parameters has been measured by terephthalic acid chemical dosimetry and subharmonic analysis. Experiments were performed in the near 1 MHz fields in the progressive wave mode and effect of duty cycles changes with 2 W/cm(2) intensity (I(SATA)) and acoustic intensity changes in continuous mode on both fluorescence intensity and subharmonic intensity were measured. The dependence between fluorescence intensity of terephthalic acid chemical dosimetry and subharmonic intensity analysis were analyzed by Pearson correlation (p-value <0.05). It has been shown that the subharmonic intensity and the fluorescence intensity for continuous mode is higher than for pulsing mode (p-value <0.05). Also results show that there is a significant difference between the subharmonic intensity and the fluorescence intensity with sonication intensity (p-value <0.05). A significant correlation between the fluorescence intensity and subharmonic intensity at different duty cycles (R=0.997, p-value <0.05) and different intensities (R=0.985, p-value <0.05) were shown. The subharmonic intensity (microW/cm(2)) significantly correlated with the fluorescence intensity (count) (R=0.901; p<0.05) and the fluorescence intensity due to chemical dosimetry could be estimated with subharmonic intensity due to subharmonic spectrum analysis. It is concluded that there is dependence between terephthalic acid chemical dosimetry and subharmonic spectrum analysis to examine the acoustic cavitation activity. PMID:20236851

Hasanzadeh, Hadi; Mokhtari-Dizaji, Manijhe; Bathaie, S Zahra; Hassan, Zuhair M

2010-06-01

447

Correlates of Bone Mineral Density and Sagittal Spinal Balance in the Aged  

PubMed Central

Objective To investigate the relationship between bone mineral density (BMD) and sagittal spinal balance in the Korean elderly population. Methods The retrospective study included subjects aged 60 years and above, who had whole-spine lateral radiography and dual-energy X-ray absorptiometry (DEXA) within a year's gap between each other. Sagittal vertical axis (SVA) for evaluation of sagittal spinal balance and five spinopelvic parameters were measured through radiography. The presence of compression fracture was identified. Correlations of BMD T-scores with SVA and with the spinopelvic parameters were assessed using Pearson correlation coefficient (PCC). Linear regression analyses were performed between SVA and the clinical and radiologic variables. Results One hundred twenty-two subjects (42 males and 80 females; mean age, 69.93±5.5 years) were included in the study. BMD, femur or spine, was not correlated with SVA or any spinopelvic parameters in both genders (PCC<±0.2), except that spine BMD in men was associated with sacral slope. Univariate regression analysis revealed association between SVA and lumbar lordosis, pelvic tilt, and compression fractures in both genders; it was also associated with age and pelvic incidence in females and with sacral slope in males. Multivariate linear regression model showed lumbar lordosis and compression fracture as variables affecting SVA in both sexes; pelvic incidence was another factor affecting SVA in women only. Conclusion BMD was not associated with sagittal spinal balance in the aged. Sagittal spinal balance was explained partly by lumbar lordosis and compression fracture. Further study is warranted to understand progression of sagittal imbalance with age.

Cho, Yung; Lee, Gangpyo; Aguinaldo, Jhoan; Lee, Kun-Jai

2015-01-01

448

Rac1 is correlated with aggressiveness and a potential therapeutic target for gastric cancer.  

PubMed

Rac1 is a member of the Rho GTPase family. Rac1 activity is critical in regulating cytoskeleton organization and thus, modulates a diverse spectrum of cellular functions in normal and malignant cells. The aims of the present study were to investigate the expression pattern and clinical significance of Rac1, as well as the role of Rac1 in gastric cancer tumorigenesis and metastasis. The expression of Rac1 in human gastric cancer was explored by immunohistochemistry. The correlation of Rac1 expression with the clinicopathological characteristics and the survival of patients were analyzed by Pearson's Chi-square and Kaplan-Meier analyses, respectively. Rac1 overexpression cell model was used to examine in vitro and in vivo effects of Rac1 in cell growth, migration and invasion. Rac1 was highly expressed in gastric cancer tissues and correlated with differentiation, local invasion, lymph node metastasis and Lauren's classification. Rac1 expression in gastric cancer predicted shorter survival. Overexpression of Rac1 in gastric cancer cells dramatically induced Rac1 activation and rendered a more aggressive phenotype such as increased cell growth and migration/invasion in vitro and in vivo. Inhibiting Rac1 activity by specific inhibitor abrogated the effects of Rac1 on the malignant phenotype. Our clinical findings demonstrated that Rac1 was well correlated with aggressiveness and a negative prognostic factor. In addition, our data on experimental cell models supported the fundamental role of Rac1 in gastric cancer. Given its pivotal role in gastric tumorigenesis and progression, Rac1 can serve as a promising therapeutic target for gastric cancer. PMID:25585795

Ji, Jun; Feng, Xiaojing; Shi, Min; Cai, Qu; Yu, Yingyan; Zhu, Zhenggang; Zhang, Jun

2015-03-01

449

A Correlational Study of Scoliosis and Trunk Balance in Adult Patients with Mandibular Deviation  

PubMed Central

Previous studies have confirmed that patients with mandibular deviation often have abnormal morphology of their cervical vertebrae. However, the relationship between mandibular deviation, scoliosis, and trunk balance has not been studied. Currently, mandibular deviation is usually treated as a single pathology, which leads to poor clinical efficiency. We investigated the relationship of spine coronal morphology and trunk balance in adult patients with mandibular deviation, and compared the finding to those in healthy volunteers. 35 adult patients with skeletal mandibular deviation and 10 healthy volunteers underwent anterior X-ray films of the head and posteroanterior X-ray films of the spine. Landmarks and lines were drawn and measured on these films. The axis distance method was used to measure the degree of scoliosis and the balance angle method was used to measure trunk balance. The relationship of mandibular deviation, spine coronal morphology and trunk balance was evaluated with the Pearson correlation method. The spine coronal morphology of patients with mandibular deviation demonstrated an “S” type curve, while a straight line parallel with the gravity line was found in the control group (significant difference, p<0.01). The trunk balance of patients with mandibular deviation was disturbed (imbalance angle >1°), while the control group had a normal trunk balance (imbalance angle <1°). There was a significant difference between the two groups (p<0.01). The degree of scoliosis and shoulder imbalance correlated with the degree of mandibular deviation, and presented a linear trend. The direction of mandibular deviation was the same as that of the lateral bending of thoracolumbar vertebrae, which was opposite to the direction of lateral bending of cervical vertebrae. Our study shows the degree of mandibular deviation has a high correlation with the degree of scoliosis and trunk imbalance, all the three deformities should be clinically evaluated in the management of mandibular deviation. PMID:23555836

Yang, Yang; Wang, Na; Wang, Wenyong; Ding, Yin; Sun, Shiyao

2013-01-01

450

Determining $?$ from cluster correlation function  

E-print Network

It is shown how data on the cluster correlation function can be used in order to reconstruct the density of the pregalactic density field on the cluster mass scale. The method is applied to the data on the cluster correlation amplitude -- richness dependence. The spectrum of the recovered density field has the same shape as the density field derived from data on the galaxy correlation function which is measured as function of linear scales. Matching the two amplitudes relates the mass to the comoving scale it contains and thereby leads to a direct determination of $\\Omega$. The resultant density parameter turns out to be $\\Omega$=0.25.

A. Kashlinsky

1998-06-17

451

Correlation, Cost Risk, and Geometry  

NASA Technical Reports Server (NTRS)

The geometric viewpoint identifies the choice of a correlation matrix for the simulation of cost risk with the pairwise choice of data vectors corresponding to the parameters used to obtain cost risk. The correlation coefficient is the cosine of the angle between the data vectors after translation to an origin at the mean and normalization for magnitude. Thus correlation is equivalent to expressing the data in terms of a non orthogonal basis. To understand the many resulting phenomena requires the use of the tensor concept of raising the index to transform the measured and observed covariant components into contravariant components before vector addition can be applied. The geometric viewpoint also demonstrates that correlation and covariance are geometric properties, as opposed to purely statistical properties, of the variates. Thus, variates from different distributions may be correlated, as desired, after selection from independent distributions. By determining the principal components of the correlation matrix, variates with the desired mean, magnitude, and correlation can be generated through linear transforms which include the eigenvalues and the eigenvectors of the correlation matrix. The conversion of the data to a non orthogonal basis uses a compound linear transformation which distorts or stretches the data space. Hence, the correlated data does not have the same properties as the uncorrelated data used to generate it. This phenomena is responsible for seemingly strange observations such as the fact that the marginal distributions of the correlated data can be quite different from the distributions used to generate the data. The joint effect of statistical distributions and correlation remains a fertile area for further research. In terms of application to cost estimating, the geometric approach demonstrates that the estimator must have data and must understand that data in order to properly choose the correlation matrix appropriate for a given estimate. There is a general feeling by employers and managers that the field of cost requires little technical or mathematical background. Contrary to that opinion, this paper demonstrates that a background in mathematics equivalent to that needed for typical engineering and scientific disciplines at the masters or doctorate level is appropriate within the field of cost risk.

Dean, Edwin B.

1992-01-01

452

Optical coherence correlation spectroscopy (OCCS).  

PubMed

We present a new method called optical coherence correlation spectroscopy (OCCS) using nanoparticles as reporters of kinetic processes at the single particle level. OCCS is a spectral interferometry based method, thus giving simultaneous access to several sampling volumes along the optical axis. Based on an auto-correlation analysis, we extract the diffusion coefficients and concentrations of nanoparticles over a large concentration range. The cross-correlation analysis between adjacent sampling volumes allows to measure flow parameters. This shows the potential of OCCS for spatially resolved diffusion and flow measurements. PMID:24515038

Broillet, Stephane; Sato, Akihiro; Geissbuehler, Stefan; Pache, Christophe; Bouwens, Arno; Lasser, Theo; Leutenegger, Marcel

2014-01-13

453

Correlations among Stress Parameters, Meat and Carcass Quality Parameters in Pigs  

PubMed Central

Relationships among different stress parameters (lairage time and blood level of lactate and cortisol), meat quality parameters (initial and ultimate pH value, temperature, drip loss, sensory and instrumental colour, marbling) and carcass quality parameters (degree of rigor mortis and skin damages, hot carcass weight, carcass fat thickness, meatiness) were determined in pigs (n = 100) using Pearson correlations. After longer lairage, blood lactate (p<0.05) and degree of injuries (p<0.001) increased, meat became darker (p<0.001), while drip loss decreased (p<0.05). Higher lactate was associated with lower initial pH value (p<0.01), higher temperature (p<0.001) and skin blemishes score (p<0.05) and more developed rigor mortis (p<0.05), suggesting that lactate could be a predictor of both meat quality and the level of preslaughter stress. Cortisol affected carcass quality, so higher levels of cortisol were associated with increased hot carcass weight, carcass fat thickness on the back and at the sacrum and marbling, but also with decreased meatiness. The most important meat quality parameters (pH and temperature after 60 minutes) deteriorated when blood lactate concentration was above 12 mmol/L. PMID:25656214

Dokmanovic, Marija; Baltic, Milan Z.; Duric, Jelena; Ivanovic, Jelena; Popovic, Ljuba; Todorovic, Milica; Markovic, Radmila; Pantic, Srdan

2015-01-01

454

Correlations among Stress Parameters, Meat and Carcass Quality Parameters in Pigs.  

PubMed

Relationships among different stress parameters (lairage time and blood level of lactate and cortisol), meat quality parameters (initial and ultimate pH value, temperature, drip loss, sensory and instrumental colour, marbling) and carcass quality parameters (degree of rigor mortis and skin damages, hot carcass weight, carcass fat thickness, meatiness) were determined in pigs (n = 100) using Pearson correlations. After longer lairage, blood lactate (p<0.05) and degree of injuries (p<0.001) increased, meat became darker (p<0.001), while drip loss decreased (p<0.05). Higher lactate was associated with lower initial pH value (p<0.01), higher temperature (p<0.001) and skin blemishes score (p<0.05) and more developed rigor mortis (p<0.05), suggesting that lactate could be a predictor of both meat quality and the level of preslaughter stress. Cortisol affected carcass quality, so higher levels of cortisol were associated with increased hot carcass weight, carcass fat thickness on the back and at the sacrum and marbling, but also with decreased meatiness. The most important meat quality parameters (pH and temperature after 60 minutes) deteriorated when blood lactate concentration was above 12 mmol/L. PMID:25656214

Dokmanovic, Marija; Baltic, Milan Z; Duric, Jelena; Ivanovic, Jelena; Popovic, Ljuba; Todorovic, Milica; Markovic, Radmila; Pantic, Srdan

2015-03-01

455

Correlating multispectral imaging and compositional data from the Mars Exploration Rovers and implications for Mars Science Laboratory  

USGS Publications Warehouse

In an effort to infer compositional information about distant targets based on multispectral imaging data, we investigated methods of relating Mars Exploration Rover (MER) Pancam multispectral remote sensing observations to in situ alpha particle X-ray spectrometer (APXS)-derived elemental abundances and Mössbauer (MB)-derived abundances of Fe-bearing phases at the MER field sites in Gusev crater and Meridiani Planum. The majority of the partial correlation coefficients between these data sets were not statistically significant. Restricting the targets to those that were abraded by the rock abrasion tool (RAT) led to improved Pearson’s correlations, most notably between the red–blue ratio (673 nm/434 nm) and Fe3+-bearing phases, but partial correlations were not statistically significant. Partial Least Squares (PLS) calculations relating Pancam 11-color visible to near-IR (VNIR; ?400–1000 nm) “spectra” to APXS and Mössbauer element or mineral abundances showed generally poor performance, although the presence of compositional outliers led to improved PLS results for data from Meridiani. When the Meridiani PLS model for pyroxene was tested by predicting the pyroxene content of Gusev targets, the results were poor, indicating that the PLS models for Meridiani are not applicable to data from other sites. Soft Independent Modeling of Class Analogy (SIMCA) classification of Gusev crater data showed mixed results. Of the 24 Gusev test regions of interest (ROIs) with known classes, 11 had >30% of the pixels in the ROI classified correctly, while others were mis-classified or unclassified. k-Means clustering of APXS and Mössbauer data was used to assign Meridiani targets to compositional classes. The clustering-derived classes corresponded to meaningful geologic and/or color unit differences, and SIMCA classification using these classes was somewhat successful, with >30% of pixels correctly classified in 9 of the 11 ROIs with known classes. This work shows that the relationship between SWIR multispectral imaging data and APXS- and Mössbauer-derived composition/mineralogy is often weak, a perhaps not entirely unexpected result given the different surface sampling depths of SWIR imaging (uppermost few microns) vs. APXS (tens of ?m) and MB measurements (hundreds of ?m). Results from the upcoming Mars Science Laboratory (MSL) rover’s ChemCam Laser Induced Breakdown Spectroscopy (LIBS) instrument may show a closer relationship to Mastcam SWIR multispectral observations, however, because the initial laser shots onto a target will analyze only the upper few micrometers of the surface. The clustering and classification methods used in this study can be applied to any data set to formalize the definition of classes and identify targets that do not fit in previously defined classes.

Anderson, Ryan B.; Bell, James F., III

2013-01-01

456

WIDAR Correlator Backend Software Design  

E-print Network

WIDAR Correlator Backend Software Design Martin Pokorny #12;i Revision history Revision Date and console app; added description of pipelinefs to head node soft- ware section. mpp 0.2 19 Sep 2007 Changed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 Head node software

Groppi, Christopher

457

Illusory correlations in graphological inference.  

PubMed

The authors investigate the illusory correlation phenomenon as a possible contributor to the persistence of graphology's use to predict personality. Participants unfamiliar with graphology inspected handwriting samples paired with fabricated personality profiles. In Experiment 1, handwriting samples and personality profiles were randomly paired. In Experiment 2, discernible correlations near unity were set between targeted handwriting-feature-personality-trait pairs in a congruent or incongruent direction with graphologists' claims. In both experiments, participants' judgments of the correlation between designated handwriting-feature-personality-trait pairs agreed with graphologists' claims, even after controlling for their actual statistical association. Semantic association between words used to describe handwriting features and personality traits was the source of biases in perceived correlation. Results may partially account for continued use of graphology despite overwhelming evidence against its predictive validity. PMID:11218342

King, R N; Koehler, D J

2000-12-01

458

Modernizing the JPL VLBI Correlator  

NASA Astrophysics Data System (ADS)

This poster will present the current capabilities of the JPL VLBI Correlator (JVC) and the general architecture of the equipment. In addition, the scientific and navigation uses of the JVC will be enumerated for background purposes. The JVC is a software correlator based on a Beowulf cluster of computers. It replaces a thirty year old correlator based on custom designed digital hardware. General comparisons between the old and new equipment will be made. The JVC makes use of a separate program, SoftC, to do the actual correlations. The JVC manages the sending of data to multiple machines in a Beowulf cluster each running SoftC in parallel on small chunks of the data. The basic architecture of SoftC will also be described.

Rogstad, S.; Goodhart, C. E.; Clark, J. E.; Finley, S.; Lanyi, G. E.; White, L. A.; Jacobs, Christopher S.>

459

Digital correlator with fewer IC's  

NASA Technical Reports Server (NTRS)

Digital correlator requires only few integrated circuits to determine synchronization of two 24-bit digital words. Circuit is easily reduced or expanded to accommodate shorter or longer words and can be utilized in industrial and commercial data processing and telecommunications.

Apple, G. G.; Rubin, L.

1979-01-01

460

Correlation and Regression Worksheet 1  

E-print Network

Correlation and Regression Worksheet 1 1. Global warming has many indirect effects on climate. As the climate warms and winter snow cover in Europe and Asia decreases, the land heats up more rapidly in summer

Watkins, Joseph C.

461

Multiple Correlation versus Multiple Regression.  

ERIC Educational Resources Information Center

Describes differences between multiple correlation analysis (MCA) and multiple regression analysis (MRA), showing how these approaches involve different research questions and study designs, different inferential approaches, different analysis strategies, and different reported information. (SLD)

Huberty, Carl J.

2003-01-01

462

Acoustic Correlates of Information Structure.  

E-print Network

This paper reports three studies aimed at addressing three questions about the acoustic correlates of information structure in English: (1) do speakers mark information structure prosodically, and, to the extent they do; ...

Breen, Mara

463

Does the intensity of diffuse thyroid gland uptake on F-18 fluorodeoxyglucose positron emission tomography/computed tomography scan predict the severity of hypothyroidism? Correlation between maximal standardized uptake value and serum thyroid stimulating hormone levels  

PubMed Central

Context: F-18 fluorodeoxyglucose (F-18 FDG) positron emission tomography/computed tomography (PET/CT) scan and hypothyroidism. Aims: The aim was to determine whether the intensity of diffuse thyroid gland uptake on F-18 FDG PET/CT scans predicts the severity of hypothyroidism. Materials and Methods: A retrospective analysis of 3868 patients who underwent F-18 FDG PET/CT scans, between October 2012 and June 2013 in our institution for various oncological indications was done. Out of them, 106 (2.7%) patients (79 females, 27 males) presented with bilateral diffuse thyroid gland uptake as an incidental finding. These patients were investigated retrospectively and various parameters such as age, sex, primary cancer site, maximal standardized uptake value (SUVmax), results of thyroid function tests (TFTs) and fine-needle aspiration cytology results were noted. The SUVmax values were correlated with serum thyroid stimulating hormone (S. TSH) levels using Pearson's correlation analysis. Statistical Analysis Used: Pearson's correlation analysis. Results: Clinical information and TFT (serum FT3, FT4 and TSH levels) results were available for 31 of the 106 patients (27 females, 4 males; mean age 51.5 years). Twenty-six out of 31 patients (84%) were having abnormal TFTs with abnormal TSH levels in 24/31 patients (mean S. TSH: 22.35 ?IU/ml, median: 7.37 ?IU/ml, range: 0.074-211 ?IU/ml). Among 7 patients with normal TSH levels, 2 patients demonstrated low FT3 and FT4 levels. No significant correlation was found between maximum standardized uptake value and TSH levels (r = 0.115, P > 0.05). Conclusions: Incidentally detected diffuse thyroid gland uptake on F-18 FDG PET/CT scan was usually associated with hypothyroidism probably caused by autoimmune thyroiditis. Patients should be investigated promptly irrespective of the intensity of FDG uptake with TFTs to initiate replacement therapy and a USG examination to look for any suspicious nodules. PMID:25589800

Pruthi, Ankur; Choudhury, Partha Sarathi; Gupta, Manoj; Taywade, Sameer

2015-01-01

464

Correlated Lloyd model: Exact solution  

NASA Astrophysics Data System (ADS)

We describe an exactly solvable model of a disordered system that is a generalized Lloyd model; it differs from the classical model because the random potential is not a ?-correlated random process. We show that the exact average Green's function in this case is independent of the correlation radius of the random potential and, as in the classical Lloyd model, is a crystal Green's function whose energy argument acquires an imaginary part dependent on the disorder degree.

Kozlov, G. G.

2014-11-01

465

Magnetic correlations and neutron scattering  

Microsoft Academic Search

An introduction is given to the methods and results of some recent researches into statistical thermodynamics bearing upon the correlation functions of magnetic moments in Heisenberg-coupled spin-only magnets, and their intimate connection with neutron-scattering theory and practice is brought out. The interrelationships between the correlation function, the relaxation function, the generalized susceptibility, the power spectrum of the fluctuations and the

W. Marshall; R. D. Lowde

1968-01-01

466

Classical, Quantum and Superquantum Correlations  

NASA Astrophysics Data System (ADS)

A deeper understanding of the origin of quantum correlations is expected to allow a better comprehension of the physical principles underlying quantum mechanics. In this work, we reconsider the possibility of devising "crypto-nonlocal theories", using a terminology firstly introduced by Leggett. We generalize and simplify the investigations on this subject which can be found in the literature. At their deeper level, such theories allow nonlocal correlations which can overcome the quantum limit.

Ghirardi, Giancarlo; Romano, Raffaele

2013-01-01

467

Classical, Quantum and Superquantum Correlations  

NASA Astrophysics Data System (ADS)

A deeper understanding of the origin of quantum correlations is expected to allow a better comprehension of the physical principles underlying quantum mechanics. In this work, we reconsider the possibility of devising "crypto-nonlocal theories", using a terminology firstly introduced by Leggett. We generalize and simplify the investigations on this subject which can be found in the literature. At their deeper level, such theories allow nonlocal correlations which can overcome the quantum limit.

Ghirardi, Giancarlo; Romano, Raffaele

2012-04-01

468

Quantum Games with Correlated Noise  

E-print Network

We analyze quantum game with correlated noise through generalized quantization scheme. Four different combinations on the basis of entanglement of initial quantum state and the measurement basis are analyzed. It is shown that the advantage that a quantum player can get by exploiting quantum strategies is only valid when both the initial quantum state and the measurement basis are in entangled form. Furthermore, it is shown that for maximum correlation the effects of decoherence diminish and it behaves as a noiseless game.

Ahmad Nawaz; A. H. Toor

2006-07-20

469

UWB communication using SAW correlators  

Microsoft Academic Search

A simple approach to ultra-wideband (UWB) communication has been demonstrated using surface acoustic wave (SAW) correlators to provide direct RF-to-baseband conversion. The SAW correlators used are bi-phase shift key (BPSK) coded devices that can directly generate or detect an RF signal. This continuous wave (CW) approach to UWB communication is markedly different from the prevailing pulse-based techniques and offers advantages

Robert Brocato; Edwin Heller; J. Wendt; J. Blaich; G. Wouters; E. Gurule; G. Omdahl; D. Palmer

2004-01-01

470

Statistical Applets: Correlation and Regression  

NSDL National Science Digital Library

Created for W.H. Freeman and Co., this applet is designed to help students see correlations in data and see how outliers can affect the correlation and least-squares line. Users can input their own data points and then try to fit a line to the data and see how the sum of squares changed. The user can then also see what the lest-square line is for that set of data.

471

Level correlations in integrable systems  

Microsoft Academic Search

We derive a simple analytical expression for the level correlation function\\u000aof an integrable system. It accounts for both the lack of correlations at\\u000asmaller energy scales and for global rigidity (level number conservation) at\\u000alarger scales. We apply our results to a rectangle with incommensurate sides\\u000aand show that they are in excellent agreement with the limiting cases\\u000aestablished

R. A. Serota

2001-01-01

472

Cluster correlations in redshift space  

Microsoft Academic Search

We test an analytic model for the two-point correlations of galaxy clusters\\u000ain redshift space using the Hubble Volume N-body simulations. The correlation\\u000afunction of clusters shows no enhancement along the line of sight, due to the\\u000alack of any virialised structures in the cluster distribution. However, the\\u000adistortion of the clustering pattern due to coherent bulk motions is clearly

Nelson D. Padilla; Carlton M. Baugh

2001-01-01

473

Computable measure of quantum correlation  

NASA Astrophysics Data System (ADS)

A general state of an system is a classical-quantum state if and only if its associated -correlation matrix (a matrix constructed from the coherence vector of the party , the correlation matrix of the state, and a function of the local coherence vector of the subsystem ), has rank no larger than . Using the general Schatten -norms, we quantify quantum correlation by measuring any violation of this condition. The required minimization can be carried out for the general -norms and any function of the local coherence vector of the unmeasured subsystem, leading to a class of computable quantities which can be used to capture the quantumness of correlations due to the subsystem . We introduce two special members of these quantifiers: The first one coincides with the tight lower bound on the geometric measure of discord, so that such lower bound fully captures the quantum correlation of a bipartite system. Accordingly, a vanishing tight lower bound on the geometric discord is a necessary and sufficient condition for a state to be zero-discord. The second quantifier has the property that it is invariant under a local and reversible operation performed on the unmeasured subsystem, so that it can be regarded as a computable well-defined measure of the quantum correlations. The approach presented in this paper provides a way to circumvent the problem with the geometric discord. We provide some examples to exemplify this measure.

Akhtarshenas, S. Javad; Mohammadi, Hamidreza; Karimi, Saman; Azmi, Zahra

2015-01-01

474

The Murchison Widefield Array Correlator  

NASA Astrophysics Data System (ADS)

The Murchison Widefield Array is a Square Kilometre Array Precursor. The telescope is located at the Murchison Radio-astronomy Observatory in Western Australia. The MWA consists of 4 096 dipoles arranged into 128 dual polarisation aperture arrays forming a connected element interferometer that cross-correlates signals from all 256 inp