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1

Children's Understanding of Posterior Probability  

ERIC Educational Resources Information Center

Do young children have a basic intuition of posterior probability? Do they update their decisions and judgments in the light of new evidence? We hypothesized that they can do so extensionally, by considering and counting the various ways in which an event may or may not occur. The results reported in this paper showed that from the age of five,…

Girotto, Vittorio; Gonzalez, Michael

2008-01-01

2

Efficient search using posterior phone probability estimates.   

E-print Network

In this paper we present a novel, efficient search strategy for large vocabulary continuous speech recognition (LVCSR). The search algorithm, based on stack decoding, uses posterior phone probability estimates to substantially increase its...

Renals, Steve; Hochberg, Mike

1995-01-01

3

USING MORE INFORMATIVE POSTERIOR PROBABILITIES FOR SPEECH RECOGNITION  

E-print Network

USING MORE INFORMATIVE POSTERIOR PROBABILITIES FOR SPEECH RECOGNITION Hamed Ketabdar, Jithendra speech recognition systems by estimating more informative posteriors taking into account acoustic context knowledge). These posteriors are esti- mated based on HMM state posterior probability definition (typically

4

Computing Posterior Probabilities of Structural Features in Bayesian Networks  

E-print Network

Computing Posterior Probabilities of Structural Features in Bayesian Networks Jin Tian and Ru He) and Koivisto (2006) pre- sented algorithms that can compute the exact marginal posterior probability of a subnet- work, e.g., a single edge, in O(n2n ) time and the posterior probabilities for all n(n-1) po

Tian, Jin

5

Maximum Posterior Probability Estimators of Map Brian M. Steele  

E-print Network

Maximum Posterior Probability Estimators of Map Accuracy Brian M. Steele Correspondence should approach to map accuracy assessment based on maximum posterior probability estimators is dis- cussed-classification sampling. A calibrated maximum posterior probability estimate of map accuracy is computed by first

Steele, Brian

6

PARTIAL LIKELIHOOD FOR ESTIMATION OF MULTI-CLASS POSTERIOR PROBABILITIES  

E-print Network

PARTIAL LIKELIHOOD FOR ESTIMATION OF MULTI-CLASS POSTERIOR PROBABILITIES T d a y Adaln, Hongnzei for nonlinear signal processing [l]. In this paper, we present the general formulation for learning posterior such that the network outputs are associated with posterior class probabilities is quite attractive for a number

Adali, Tulay

7

EFFICIENT SEARCH USING POSTERIOR PHONE PROBABILITY ESTIMATES Steve Renals  

E-print Network

EFFICIENT SEARCH USING POSTERIOR PHONE PROBABILITY ESTIMATES Steve Renals Department of Computer). The search algorithm, based on stack decoding, uses posterior phone probabil­ ity estimates to substantially reduced by phone deactivation pruning where phones with a small local posterior probability

Edinburgh, University of

8

LARGE VOCABULARY DECODING AND CONFIDENCE ESTIMATION USING WORD POSTERIOR PROBABILITIES  

E-print Network

LARGE VOCABULARY DECODING AND CONFIDENCE ESTIMATION USING WORD POSTERIOR PROBABILITIES G. Evermann Email: {ge204,pcw}@eng.cam.ac.uk ABSTRACT This paper investigates the estimation of word posterior probabilities based on word lattices and presents applica- tions of these posteriors in a large vocabulary

Hain, Thomas

9

Posterior Probability Estimation Techniques Embedded in a Bayes Filter for Vibration-based  

E-print Network

Posterior Probability Estimation Techniques Embedded in a Bayes Filter for Vibration-based Terrain filter taking the posterior probability of each prediction into account. Posterior probability estimates measurements. We addressed this problem in [9]. There, we applied a Bayes filter to combine the posterior

Zell, Andreas

10

Classifier Conditional Posterior Probabilities Robert P.W. Duin, David M.J. Tax  

E-print Network

Classifier Conditional Posterior Probabilities Robert P.W. Duin, David M.J. Tax Pattern Recognition Classifiers based on probability density estimates can be used to find posterior probabilities for the objects to be classified. These probabilities can be used for rejection or for combining classifiers. Posterior

Duin, Robert P.W.

11

TO APPEAR : Statistics and Probability Letters BAYESIAN HYPOTHESES TESTING USING POSTERIOR DENSITY RATIOS  

E-print Network

TO APPEAR : Statistics and Probability Letters BAYESIAN HYPOTHESES TESTING USING POSTERIOR DENSITY 72701, USA Email : sbasu@comp.uark.edu February, 1995 Revised August, 1995 Abstract The posterior hypothesis testing. The performances of the posterior density ratio and the posterior probability of H 0

Basu, Sanjib

12

HMMs Viterbi Forward Posterior Probabilities Applications Training The Beyond Hidden Markov Models  

E-print Network

HMMs Viterbi Forward Posterior Probabilities Applications Training The Beyond Hidden Markov Models Rune Lyngsø 2nd of November 2011 #12;HMMs Viterbi Forward Posterior Probabilities Applications Training The Beyond Outline Hidden Markov Models Viterbi Algorithm Full Likelihood Computation Posterior Probabilities

Goldschmidt, Christina

13

Posterior Error Probabilities and False Discovery Rates: Two Sides of the Same Coin  

E-print Network

Posterior Error Probabilities and False Discovery Rates: Two Sides of the Same Coin Lukas Käll, the q-value and the posterior error probability, are related and complementary to one another. Keywords: q-value · posterior error probability · false discovery rate · statistical significance · peptide

Storey, John D.

14

Accurate Approximations for Posterior Moments and Marginal Densities  

Microsoft Academic Search

This article describes approximations to the posterior means and variances of positive functions of a real or vector-valued parameter, and to the marginal posterior densities of arbitrary (i.e., not necessarily positive) parameters. These approximations can also be used to compute approximate predictive densities. To apply the proposed method, one only needs to be able to maximize slightly modified likelihood functions

Luke Tierney; Joseph B. Kadane

1986-01-01

15

Efficient posterior probability mapping using Savage-Dickey ratios.  

PubMed

Statistical Parametric Mapping (SPM) is the dominant paradigm for mass-univariate analysis of neuroimaging data. More recently, a bayesian approach termed Posterior Probability Mapping (PPM) has been proposed as an alternative. PPM offers two advantages: (i) inferences can be made about effect size thus lending a precise physiological meaning to activated regions, (ii) regions can be declared inactive. This latter facility is most parsimoniously provided by PPMs based on bayesian model comparisons. To date these comparisons have been implemented by an Independent Model Optimization (IMO) procedure which separately fits null and alternative models. This paper proposes a more computationally efficient procedure based on Savage-Dickey approximations to the Bayes factor, and Taylor-series approximations to the voxel-wise posterior covariance matrices. Simulations show the accuracy of this Savage-Dickey-Taylor (SDT) method to be comparable to that of IMO. Results on fMRI data show excellent agreement between SDT and IMO for second-level models, and reasonable agreement for first-level models. This Savage-Dickey test is a bayesian analogue of the classical SPM-F and allows users to implement model comparison in a truly interactive manner. PMID:23533640

Penny, William D; Ridgway, Gerard R

2013-01-01

16

Estimating the Posterior Probabilities Using the K-Nearest Neighbor Rule  

E-print Network

Estimating the Posterior Probabilities Using the K-Nearest Neighbor Rule Amir F. Atiya Dept pattern classification problems an estimate of the posterior prob- abilities (rather than only is needed. In this paper we propose a new posterior probability estimator. The proposed estimator considers

Abu-Mostafa, Yaser S.

17

On Using Entropy Information to Improve Posterior Probability-based Confidence Measures  

E-print Network

On Using Entropy Information to Improve Posterior Probability-based Confidence Measures Tzan. In this paper, we propose a novel approach that reduces the confidence error rate of traditional posterior enhances the discriminability of confidence measures by applying entropy information to the posterior

Wang, Hsin-Min

18

130 IEEE TRANSACTIONS ON NEURAL NETWORKS, VOL. 19, NO. 1, JANUARY 2008 Multiclass Posterior Probability  

E-print Network

130 IEEE TRANSACTIONS ON NEURAL NETWORKS, VOL. 19, NO. 1, JANUARY 2008 Multiclass Posterior Abstract--Tao et al. have recently proposed the posterior proba- bility support vector machine (PPSVM) which uses soft labels de- rived from estimated posterior probabilities to be more robust to noise

Alpaydýn, Ethem

19

A Posterior Probability-Based System Hybridisation and Combination for Spoken Term Detection  

E-print Network

A Posterior Probability-Based System Hybridisation and Combination for Spoken Term Detection Javier perfor- mance, we have presented a direct posterior-based confidence measure generated from a neural posterior confidence measure, in which the deci- sion making is totally separated from the term detection

Edinburgh, University of

20

Bayesian model selection using exact and approximated posterior probabilities with applications to Star Data  

E-print Network

This research consists of two parts. The ?rst part examines the posterior probability integrals for a family of linear models which arises from the work of Hart, Koen and Lombard (2003). Applying Laplace's method to these integrals...

Pokta, Suriani

2004-11-15

21

Computation of the Posterior Probability of Linkage Using ‘High Effect’ Genetic Model Priors  

Microsoft Academic Search

Objectives: The posterior probability of linkage, or PPL, directly measures the probability that a disease gene is linked to a marker. By placing a Bayesian prior on the elements of the genetic model, it allows for an unknown genetic model without the inflationary effects of maximization. The standard technique uses essentially uniform priors over the elements of the penetrance vector.

M. W. Logue; Y. Li

2008-01-01

22

Inference of posterior inclusion probability of QTLs in Bayesian shrinkage analysis.  

PubMed

Bayesian shrinkage analysis estimates all QTLs effects simultaneously, which shrinks the effect of "insignificant" QTLs close to zero so that it does not need special model selection. Bayesian shrinkage estimation usually has an excellent performance on multiple QTLs mapping, but it could not give a probabilistic explanation of how often a QTLs is included in the model, also called posterior inclusion probability, which is important to assess the importance of a QTL. In this research, two methods, FitMix and SimMix, are proposed to approximate the posterior probabilities. Under the assumption of mixture distribution of the estimated QTL effect, FitMix and SimMix mathematically and intuitively fit mixture distribution, respectively. The simulation results showed that both methods gave very reasonable estimates for posterior probabilities. We also applied the two methods to map QTLs for the North American Barley Genome Mapping Project data. PMID:25857576

Yang, Deguang; Han, Shanshan; Jiang, Dan; Yang, Runqing; Fang, Ming

2015-01-01

23

Performance of the Rayleigh task based on the posterior probability of tomographic reconstructions  

SciTech Connect

We seek the best possible performance of the Rayleigh task in which one must decide whether a perceived object is a pair of Gaussian-blurred points or a blurred line. Two Bayesian reconstruction algorithms are used, the first based on a Gaussian prior-probability distribution with a nonnegativity constraint and the second based on an entropic prior. In both cases, the reconstructions are found that maximize the posterior probability. We compare the performance of the Rayleigh task obtained with two decision variables, the logarithm of the posterior probability ratio and the change in the mean-squared deviation from the reconstruction. The method of evaluation is based on the results of a numerical testing procedure in which the stated discrimination task is carried out on reconstructions of a randomly generated sequence of images. The ability to perform the Rayleigh task is summarized in terms of a discrimination index that is derived from the area under the receiver-operating characteristic (ROC) curve. We find that the use of the posterior probability does not result in better performance of the Rayleigh task than the mean-squared deviation from the reconstruction. 10 refs., 6 figs.

Hanson, K.M.

1991-01-01

24

An Accurate SER Estimation Method Based on Propagation Probability Ghazanfar Asadi and Mehdi B. Tahoori  

E-print Network

An Accurate SER Estimation Method Based on Propagation Probability Ghazanfar Asadi and Mehdi B}@ece.neu.edu Abstract In this paper, we present an accurate but very fast soft error rate (SER) estimation technique, arise from energetic particles, namely neutrons and alpha particles. Soft Error Rate (SER) for a device

Paris-Sud XI, Université de

25

Laser Raman detection for oral cancer based on an adaptive Gaussian process classification method with posterior probabilities  

NASA Astrophysics Data System (ADS)

The existing methods for early and differential diagnosis of oral cancer are limited due to the unapparent early symptoms and the imperfect imaging examination methods. In this paper, the classification models of oral adenocarcinoma, carcinoma tissues and a control group with just four features are established by utilizing the hybrid Gaussian process (HGP) classification algorithm, with the introduction of the mechanisms of noise reduction and posterior probability. HGP shows much better performance in the experimental results. During the experimental process, oral tissues were divided into three groups, adenocarcinoma (n = 87), carcinoma (n = 100) and the control group (n = 134). The spectral data for these groups were collected. The prospective application of the proposed HGP classification method improved the diagnostic sensitivity to 56.35% and the specificity to about 70.00%, and resulted in a Matthews correlation coefficient (MCC) of 0.36. It is proved that the utilization of HGP in LRS detection analysis for the diagnosis of oral cancer gives accurate results. The prospect of application is also satisfactory.

Du, Zhanwei; Yang, Yongjian; Bai, Yuan; Wang, Lijun; Su, Le; Chen, Yong; Li, Xianchang; Zhou, Xiaodong; Jia, Jun; Shen, Aiguo; Hu, Jiming

2013-03-01

26

ACCURATE POSTERIOR PROBABILITY ESTIMATES FOR CHANNEL EQUALIZATION USING GAUSSIAN PROCESSES FOR CLASSIFICATION  

E-print Network

by the Spanish MEC (TIC2006- 13514-C01-01/TCM). This work has been partially supported by the Spanish MEC (TEC], radial basis functions (RBFs) [3], recurrent RBFs [4], self-organizing feature maps [5], wavelet neural

Pérez-Cruz, Fernando

27

A Posterior Probability-based System Hybridisation and Combination for Spoken Term Detection   

E-print Network

Spoken term detection (STD) is a fundamental task for multimedia information retrieval. To improve the detection performance, we have presented a direct posterior-based confidence measure generated from a neural network. In this paper, we propose a...

Tejedor, Javier; Wang, Dong; King, Simon; Frankel, Joe; Colas, Jose

2009-01-01

28

The probability for anterior and posterior presentation during the second half of gestation and at delivery among albino mice  

Microsoft Academic Search

The aim of this research is to determine the probability of anterior and posterior presentation during the second half of\\u000a gestation and at delivery among albino mice. Each day from the 10th to the 21st day of gestation, foetal presentation and lie were determined in uteri of six pregnant females. The chi-square test did not\\u000a show any statistically significant difference

Slobodan Sekuli?; Dušan Laloševi?; Nada Naumovi?; Sr?an Puti?; Milka ?uli?

2007-01-01

29

A simple, accurate method to calculate spread-spectrum multiple-access error probabilities  

Microsoft Academic Search

The exact calculation of error probabilities for direct-sequence spread-spectrum multiple-access (DS\\/SSMA) systems has been addressed in the literature. The exact calculation is computationally difficult, so emphasis has been on approximations and bounds. One particularly attractive approximation is to just use a signal-to-noise ratio in a Gaussian approximation, the `standard approximation'. Unfortunately, that approximation is not generally accurate enough. An improved

Jack M. Holtzman

1992-01-01

30

Building a Model Using Bayesian Network for Assessment of Posterior Probabilities of Falling From Height at Workplaces  

PubMed Central

Background: Falls from height are one of the main causes of fatal occupational injuries. The objective of this study was to present a model for estimating occurrence probability of falling from height. Methods: In order to make a list of factors affecting falls, we used four expert group's judgment, literature review and an available database. Then the validity and reliability of designed questionnaire were determined and Bayesian networks were built. The built network, nodes and curves were quantified. For network sensitivity analysis, four types of analysis carried out. Results: A Bayesian network for assessment of posterior probabilities of falling from height proposed. The presented Bayesian network model shows the interrelationships among 37 causes affecting the falling from height and can calculate its posterior probabilities. The most important factors affecting falling were Non-compliance with safety instructions for work at height (0.127), Lack of safety equipment for work at height (0.094) and Lack of safety instructions for work at height (0.071) respectively. Conclusion: The proposed Bayesian network used to determine how different causes could affect the falling from height at work. The findings of this study can be used to decide on the falling accident prevention programs. PMID:25648498

Alizadeh, Seyed Shamseddin; Mortazavi, Seyed Bagher; Sepehri, Mohammad Mehdi

2014-01-01

31

Fig. S1: Study of the histogram of the distribution of values { };0 ;1 500i N i N N represented in Fig. 2. A. Logarithm of the posterior probability (LPP) of bin number N  

E-print Network

in Fig. 2. A. Logarithm of the posterior probability (LPP) of bin number N (as defined in ref. 36 of the LPP on the optimal number of bin. A: the Log Posterior Probability (LPP) calculated on the original dithering, the Log Posterior Probability (LPP: gray curve in A, C, E) is very noisy and the definition

Michalet, Xavier

32

Adapting the posterior probability of diagnosis index to enhance evidence-based screening: an application to ADHD in primary care.  

PubMed

This study adapts the Posterior Probability of Diagnosis (PPOD) Index for use with screening data. The original PPOD Index, designed for use in the context of comprehensive diagnostic assessments, is overconfident when applied to screening data. To correct for this overconfidence, we describe a simple method for adjusting the PPOD Index to improve its calibration when used for screening. Specifically, we compare the adjusted PPOD Index to the original index and naïve Bayes probability estimates on two dimensions of accuracy, discrimination and calibration, using a clinical sample of children and adolescents (N = 321) whose caregivers completed the Vanderbilt Assessment Scale to screen for attention-deficit/hyperactivity disorder and who subsequently completed a comprehensive diagnostic assessment. Results indicated that the adjusted PPOD Index, original PPOD Index, and naïve Bayes probability estimates are comparable using traditional measures of accuracy (sensitivity, specificity, and area under the curve), but the adjusted PPOD Index showed superior calibration. We discuss the importance of calibration for screening and diagnostic support tools when applied to individual patients. PMID:25000935

Lindhiem, Oliver; Yu, Lan; Grasso, Damion J; Kolko, David J; Youngstrom, Eric A

2015-04-01

33

Two novel quantitative trait linkage analysis statistics based on the posterior probability of linkage: application to the COGA families  

PubMed Central

Background In this paper we apply two novel quantitative trait linkage statistics based on the posterior probability of linkage (PPL) to chromosome 4 from the GAW 14 COGA dataset. Our approaches are advantageous since they use the full likelihood, use full phenotypic information, do not assume normality at the population level or require population/sample parameter estimates; and like other forms of the PPL, they are specifically tailored to accumulate linkage evidence, either for or against linkage, across multiple sets of heterogeneous data. Results The first statistic uses all quantitative trait (QT) information from the pedigree (QT-posterior probability of linkage, PPL); we applied the QT-PPL to the trait ecb21 (resting electroencephalogram). The second statistic allows simultaneous incorporation of dichotomous trait data into the QT analysis via a threshold model (QTT-PPL); we applied the QTT-PPL to combined data on ecb21 and ALDX1. We obtained a QT-PPL of 96% at GABRB1 and a QT-PPL of 18% at FABP2 while the QTT-PPL was 4% and 2% at the same two loci, respectively. By comparison, the variance-components (VC) method, as implemented in SOLAR, yielded multipoint VC LOD scores of 2.05 and 2.21 at GABRB1 and FABP2, respectively; no other VC LODs were greater than 2. Conclusion The QTT-PPL was only 4% at GABARB1, which might suggest that the underlying ecb21 gene does not also cause ALDX1, although features of the data complicate interpretation of this result. PMID:16451579

Bartlett, Christopher W; Vieland, Veronica J

2005-01-01

34

Multipoint Approximations of Identity-by-Descent Probabilities for Accurate Linkage Analysis of Distantly Related Individuals  

PubMed Central

We propose an analytical approximation method for the estimation of multipoint identity by descent (IBD) probabilities in pedigrees containing a moderate number of distantly related individuals. We show that in large pedigrees where cases are related through untyped ancestors only, it is possible to formulate the hidden Markov model of the Lander-Green algorithm in terms of the IBD configurations of the cases. We use a first-order Markov approximation to model the changes in this IBD-configuration variable along the chromosome. In simulated and real data sets, we demonstrate that estimates of parametric and nonparametric linkage statistics based on the first-order Markov approximation are accurate. The computation time is exponential in the number of cases instead of in the number of meioses separating the cases. We have implemented our approach in the computer program ALADIN (accurate linkage analysis of distantly related individuals). ALADIN can be applied to general pedigrees and marker types and has the ability to model marker-marker linkage disequilibrium with a clustered-markers approach. Using ALADIN is straightforward: It requires no parameters to be specified and accepts standard input files. PMID:18319071

Albers, Cornelis A.; Stankovich, Jim; Thomson, Russell; Bahlo, Melanie; Kappen, Hilbert J.

2008-01-01

35

Multipoint approximations of identity-by-descent probabilities for accurate linkage analysis of distantly related individuals.  

PubMed

We propose an analytical approximation method for the estimation of multipoint identity by descent (IBD) probabilities in pedigrees containing a moderate number of distantly related individuals. We show that in large pedigrees where cases are related through untyped ancestors only, it is possible to formulate the hidden Markov model of the Lander-Green algorithm in terms of the IBD configurations of the cases. We use a first-order Markov approximation to model the changes in this IBD-configuration variable along the chromosome. In simulated and real data sets, we demonstrate that estimates of parametric and nonparametric linkage statistics based on the first-order Markov approximation are accurate. The computation time is exponential in the number of cases instead of in the number of meioses separating the cases. We have implemented our approach in the computer program ALADIN (accurate linkage analysis of distantly related individuals). ALADIN can be applied to general pedigrees and marker types and has the ability to model marker-marker linkage disequilibrium with a clustered-markers approach. Using ALADIN is straightforward: It requires no parameters to be specified and accepts standard input files. PMID:18319071

Albers, Cornelis A; Stankovich, Jim; Thomson, Russell; Bahlo, Melanie; Kappen, Hilbert J

2008-03-01

36

Multipoint Approximations of Identity-by-Descent Probabilities for Accurate Linkage Analysis of Distantly Related Individuals  

Microsoft Academic Search

We propose an analytical approximation method for the estimation of multipoint identity by descent (IBD) probabilities in pedigrees containing a moderate number of distantly related individuals. We show that in large pedigrees where cases are related through untyped ancestors only, it is possible to formulate the hidden Markov model of the Lander-Green algorithm in terms of the IBD configurations of

Cornelis A. Albers; Jim Stankovich; Russell Thomson; Melanie Bahlo; Hilbert J. Kappen

2008-01-01

37

A three-step Maximum-A-Posterior probability method for InSAR data inversion of coseismic rupture with application to four recent large earthquakes in Asia  

NASA Astrophysics Data System (ADS)

We develop a three-step Maximum-A-Posterior probability (MAP) method for coseismic rupture inversion, which aims at maximizing the a posterior probability density function (PDF) of elastic solutions of earthquake rupture. The method originates from the Fully Bayesian Inversion (FBI) and the Mixed linear-nonlinear Bayesian inversion (MBI) methods , shares the same a posterior PDF with them and keeps most of their merits, while overcoming its convergence difficulty when large numbers of low quality data are used and improving the convergence rate greatly using optimization procedures. A highly efficient global optimization algorithm, Adaptive Simulated Annealing (ASA), is used to search for the maximum posterior probability in the first step. The non-slip parameters are determined by the global optimization method, and the slip parameters are inverted for using the least squares method without positivity constraint initially, and then damped to physically reasonable range. This step MAP inversion brings the inversion close to 'true' solution quickly and jumps over local maximum regions in high-dimensional parameter space. The second step inversion approaches the 'true' solution further with positivity constraints subsequently applied on slip parameters using the Monte Carlo Inversion (MCI) technique, with all parameters obtained from step one as the initial solution. Then the slip artifacts are eliminated from slip models in the third step MAP inversion with fault geometry parameters fixed. We first used a designed model with 45 degree dipping angle and oblique slip, and corresponding synthetic InSAR data sets to validate the efficiency and accuracy of method. We then applied the method on four recent large earthquakes in Asia, namely the 2010 Yushu, China earthquake, the 2011 Burma earthquake, the 2011 New Zealand earthquake and the 2008 Qinghai, China earthquake, and compared our results with those results from other groups. Our results show the effectiveness of the method in earthquake studies and a number of advantages of it over other methods. The details will be reported on the meeting.

Sun, J.; Shen, Z.; Burgmann, R.; Liang, F.

2012-12-01

38

Probability  

NSDL National Science Digital Library

This application demomstrates simple probability concepts by having student rank the probability of an event on a probability line (from impossible to certain). After several trials the application then allows students to complete a simulation and collect data based on the probability task (retrieving balls from a machine). Several guiding questions are provided throughout the activity to encourage student dialogue.

2011-01-18

39

High posterior density ellipsoids of quantum states  

E-print Network

Regions of quantum states generalize the classical notion of error bars. High posterior density (HPD) credible regions are the most powerful of region estimators. However, they are intractably hard to construct in general. This paper reports on a numerical approximation to HPD regions for the purpose of testing a much more computationally and conceptually convenient class of regions: posterior covariance ellipsoids (PCEs). The PCEs are defined via the covariance matrix of the posterior probability distribution of states. Here it is shown that PCEs are near optimal for the example of Pauli measurements on multiple qubits. Moreover, the algorithm is capable of producing accurate PCE regions even when there is uncertainty in the model.

Christopher Ferrie

2013-10-07

40

Drug testing example for conditional probability Suppose that a drug test for an illegal drug is such that it is 98% accurate in the case of a  

E-print Network

Drug testing example for conditional probability Suppose that a drug test for an illegal drug is such that it is 98% accurate in the case of a user of that drug (e.g. it produces a positive result with probability .98 in the case that the tested individual uses the drug) and 90% accurate in the case of a non

Gross, Louis J.

41

Probability  

NSDL National Science Digital Library

This lesson is designed to develop students' understanding of probability in real life situations. Students will also be introduced to running experiments, experimental probability, and theoretical probability. This lesson provides links to discussions and activities related to probability 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

42

Fast and accurate probability density estimation in large high dimensional astronomical datasets  

NASA Astrophysics Data System (ADS)

Astronomical surveys will generate measurements of hundreds of attributes (e.g. color, size, shape) on hundreds of millions of sources. Analyzing these large, high dimensional data sets will require efficient algorithms for data analysis. An example of this is probability density estimation that is at the heart of many classification problems such as the separation of stars and quasars based on their colors. Popular density estimation techniques use binning or kernel density estimation. Kernel density estimation has a small memory footprint but often requires large computational resources. Binning has small computational requirements but usually binning is implemented with multi-dimensional arrays which leads to memory requirements which scale exponentially with the number of dimensions. Hence both techniques do not scale well to large data sets in high dimensions. We present an alternative approach of binning implemented with hash tables (BASH tables). This approach uses the sparseness of data in the high dimensional space to ensure that the memory requirements are small. However hashing requires some extra computation so a priori it is not clear if the reduction in memory requirements will lead to increased computational requirements. Through an implementation of BASH tables in C++ we show that the additional computational requirements of hashing are negligible. Hence this approach has small memory and computational requirements. We apply our density estimation technique to photometric selection of quasars using non-parametric Bayesian classification and show that the accuracy of the classification is same as the accuracy of earlier approaches. Since the BASH table approach is one to three orders of magnitude faster than the earlier approaches it may be useful in various other applications of density estimation in astrostatistics.

Gupta, Pramod; Connolly, Andrew J.; Gardner, Jeffrey P.

2015-01-01

43

Probability  

NSDL National Science Digital Library

What are the chances? What is probability? Math Glossary What are the chances that you will get a baby brother or a baby sister? Boy or Girl? If you flip more than one coin, what are the combinations you could get? What are the chances you will get each combination? Probability in Flipping Coins ...

Ms. Banks

2005-05-11

44

Probability Probability  

E-print Network

Review: Probability and Statistics Sam Roweis October 2, 2002 Probability #15;We use probabilities;ne random variables and sample spaces carefully: e.g. Prisoner's paradox Entropy #15; Measures(x). #12; Statistics #15; Probability: inferring probabilistic quantities for data given #12;xed models

Roweis, Sam

45

Assessing Goodness of Fit in Item Response Theory with Nonparametric Models: A Comparison of Posterior Probabilities and Kernel-Smoothing Approaches  

ERIC Educational Resources Information Center

The distance between nonparametric and parametric item characteristic curves has been proposed as an index of goodness of fit in item response theory in the form of a root integrated squared error index. This article proposes to use the posterior distribution of the latent trait as the nonparametric model and compares the performance of an index…

Sueiro, Manuel J.; Abad, Francisco J.

2011-01-01

46

Drug testing Example for Conditional Probability and Bayes Theorem Suppose that a drug test for an illegal drug is such that it is 98% accurate in the case of a  

E-print Network

Drug testing Example for Conditional Probability and Bayes Theorem Suppose that a drug test for an illegal drug is such that it is 98% accurate in the case of a user of that drug (e.g. it produces a positive result with probability .98 in the case that the tested individual uses the drug) and 90% accurate

Gross, Louis J.

47

Posterior sagittal proctectomy.  

PubMed Central

Rectal excision for non-malignant conditions using a posterior sagittal approach is described in three patients. The technique allows excellent exposure of the rectum, meticulous haemostasis, minimal risk of pelvic nerve injury and accurate reconstruction of the pelvic floor without the need for drainage. Images Figure 2 PMID:9623381

Stringer, M. D.; Crabbe, D. C.

1998-01-01

48

A Posterior Approach for Microphone Array Based Speech Recognition   

E-print Network

posterior-based approach for array-based speech recognition. The main idea is, instead of enhancing speech signals, we try to enhance the posterior probabilities that frames belonging to recognition units, e.g., phones. These enhanced posteriors...

Wang, Dong; Himawan, Ivan; Frankel, Joe; King, Simon

2008-01-01

49

A Fast Posterior Update for Sparse Underdetermined Linear Models  

E-print Network

A Fast Posterior Update for Sparse Underdetermined Linear Models Lee C. Potter, Philip Schniter is given for updating posterior probabilities. Emphasis is given to the underdetermined and sparse case, i posterior probability and their exact posterior odds. As a byproduct, this Bayesian model averaged approach

Schniter, Philip

50

Spondylolisthesis and posterior instability.  

PubMed

We present the case of a patient with a spondylolisthesis of L5 on S1 due to spondylolysis at the level L5/S1. The vertebral slip was fixed and no anterior instability was found. Using functional magnetic resonance imaging (MRI) in an upright MRI scanner, posterior instability at the level of the spondylolytic defect of L5 was demonstrated. A structure, probably the hypertrophic ligament flava, arising from the spondylolytic defect was displaced toward the L5 nerve root, and a bilateral contact of the displaced structure with the L5 nerve root was shown in extension of the spine. To our knowledge, this is the first case described of posterior instability in patients with spondylolisthesis. The clinical implications of posterior instability are unknown; however, it is thought that this disorder is common and that it can only be diagnosed using upright MRI. PMID:19253068

Niggemann, P; Simons, P; Kuchta, J; Beyer, H K; Frey, H; Grosskurth, D

2009-04-01

51

Posterior Probabilistic Clustering using NMF CSE Department  

E-print Network

Posterior Probabilistic Clustering using NMF Chris Ding CSE Department University of Texas of Computer Science Florida International University wpeng002@cs.fiu.edu ABSTRACT We introduce the posterior probabilistic clustering (PPC), which provides a rigorous posterior probability interpretation for Non- negative

Li, Tao

52

Posterior sampling with improved efficiency  

SciTech Connect

The Markov Chain Monte Carlo (MCMC) technique provides a means to generate a random sequence of model realizations that sample the posterior probability distribution of a Bayesian analysis. That sequence may be used to make inferences about the model uncertainties that derive from measurement uncertainties. This paper presents an approach to improving the efficiency of the Metropolis approach to MCMC by incorporating an approximation to the covariance matrix of the posterior distribution. The covariance matrix is approximated using the update formula from the BFGS quasi-Newton optimization algorithm. Examples are given for uncorrelated and correlated multidimensional Gaussian posterior distributions.

Hanson, K.M.; Cunningham, G.S.

1998-12-01

53

A two-stage fast Bayesian spectral density approach for ambient modal analysis. Part I: Posterior most probable value and uncertainty  

NASA Astrophysics Data System (ADS)

A two-stage fast Bayesian spectral density approach is proposed in this study to extract modal properties for the cases of separated modes and closely spaced modes. A novel technique for variable separation is developed so that the interaction between spectrum variables (i.e., frequency, damping ratio as well as the spectral density of modal excitation and prediction error) and spatial variables (i.e., mode shape components) can be decoupled completely for both cases. In a first stage, the spectrum variables can be identified through a so-called 'fast Bayesian spectral trace approach' (FBSTA) by employing the statistical properties of the sum of auto-spectral density, while the spatial variables can be estimated in a follow up second stage through 'fast Bayesian spectral density approach' (FBSDA) by using the statistical information of the entire spectral density matrix. This study also reveals the intrinsic relationship between FBSDA and 'fast Bayesian FFT approach' formulated recently when multiple sets of measurements are available. The newly developed two-stage Bayesian approach allows for a fast computation of the most probable values and covariance matrix of modal properties. The companion paper is devoted to assembling the local mode shape components corresponding to different setups to form the overall mode shapes using a Bayesian statistical framework and verifying the proposed algorithms through simulated and field testing data.

Yan, Wang-Ji; Katafygiotis, Lambros S.

2015-03-01

54

Radiation therapy: posterior segment complications.  

PubMed

Therapeutic radiation to the posterior segment of the eye is a common option for posterior segment tumors. Such tumors are often malignant, but sometimes, benign neoplasms are treated with ionizing radiation. Also, non-neoplastic intraocular lesions like wet age-related macular degeneration may be treated with radiotherapy. Orbital disease, both neoplastic lesions like optic nerve sheath meningioma and non-neoplastic entities like Graves' ophthalmopathy may be treated with radiotherapy and this may include radiation of the optic nerve and posterior segment of the eye. Occasionally, radiotherapy of extraocular malignant disease, involving, e.g. the paranasal sinuses, may cause significant radiation damage to the eye. Complications after radiation to the posterior segment of the eye are largely related to the radiation dose to the posterior segment. The amount of irradiated volume of normal tissue and fractionation are also important for the development of radiation complications to the posterior segment. Radiation retinopathy is the most common complication of the posterior segment, but radiation optic neuropathy also occurs frequently. Radiation scleral necrosis is less frequent probably due to the radioresistance of the scleral collagen. These complications have the potential to cause blindness (radiation retinopathy and optic neuropathy) or enucleation of the eye (scleral necrosis). Although numerous treatments have been advocated, management of radiation-induced damage remains controversial. Efficacy for any treatment still needs to be proven and, if possible, the best option by far is to minimize radiation changes to normal tissue. PMID:23989132

Seregard, Stefan; Pelayes, David E; Singh, Arun D

2013-01-01

55

Posterior fossa tumor  

MedlinePLUS

Posterior fossa tumor is a type of brain tumor located in or near the bottom of the ... The posterior fossa is a small space in the skull, found near the brainstem and cerebellum. The cerebellum is ...

56

Normal Tissue Complication Probability Estimation by the Lyman-Kutcher-Burman Method Does Not Accurately Predict Spinal Cord Tolerance to Stereotactic Radiosurgery  

SciTech Connect

Purpose: To determine whether normal tissue complication probability (NTCP) analyses of the human spinal cord by use of the Lyman-Kutcher-Burman (LKB) model, supplemented by linear-quadratic modeling to account for the effect of fractionation, predict the risk of myelopathy from stereotactic radiosurgery (SRS). Methods and Materials: From November 2001 to July 2008, 24 spinal hemangioblastomas in 17 patients were treated with SRS. Of the tumors, 17 received 1 fraction with a median dose of 20 Gy (range, 18-30 Gy) and 7 received 20 to 25 Gy in 2 or 3 sessions, with cord maximum doses of 22.7 Gy (range, 17.8-30.9 Gy) and 22.0 Gy (range, 20.2-26.6 Gy), respectively. By use of conventional values for {alpha}/{beta}, volume parameter n, 50% complication probability dose TD{sub 50}, and inverse slope parameter m, a computationally simplified implementation of the LKB model was used to calculate the biologically equivalent uniform dose and NTCP for each treatment. Exploratory calculations were performed with alternate values of {alpha}/{beta} and n. Results: In this study 1 case (4%) of myelopathy occurred. The LKB model using radiobiological parameters from Emami and the logistic model with parameters from Schultheiss overestimated complication rates, predicting 13 complications (54%) and 18 complications (75%), respectively. An increase in the volume parameter (n), to assume greater parallel organization, improved the predictive value of the models. Maximum-likelihood LKB fitting of {alpha}/{beta} and n yielded better predictions (0.7 complications), with n = 0.023 and {alpha}/{beta} = 17.8 Gy. Conclusions: The spinal cord tolerance to the dosimetry of SRS is higher than predicted by the LKB model using any set of accepted parameters. Only a high {alpha}/{beta} value in the LKB model and only a large volume effect in the logistic model with Schultheiss data could explain the low number of complications observed. This finding emphasizes that radiobiological models traditionally used to estimate spinal cord NTCP may not apply to the dosimetry of SRS. Further research with additional NTCP models is needed.

Daly, Megan E.; Luxton, Gary [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Choi, Clara Y.H. [Department of Neurosurgery, Stanford University, Stanford, CA (United States); Gibbs, Iris C. [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Chang, Steven D.; Adler, John R. [Department of Neurosurgery, Stanford University, Stanford, CA (United States); Soltys, Scott G., E-mail: sgsoltys@stanford.edu [Department of Radiation Oncology, Stanford University, Stanford, CA (United States)

2012-04-01

57

Probably?.....Probability!  

NSDL National Science Digital Library

What's your chances?! Play these three probability games to find out! Let's join the circus! Read each probability question in the game Probability Circus! and try to determine the chances of each one. There will be three circus rings to choose from, so choose wisely! Let's see how good your chances are...play Probability Pond! to determine if your chances are certain, impossible, more likely, less likely, or ...

Ms. Pearce

2011-11-11

58

Posterior Ischemic Optic Neuropathy  

Microsoft Academic Search

14 cases of posterior ischemic optic neuropathy (PION) were clinically analyzed, in whom we excluded known etiologies of optic nerve disturbances and confirmed the decreased blood supply to the posterior portion of the optic nerve. On the basis of our clinical findings, we have proposed the following criteria for the diagnosis of idiopathic PION: (1) sudden onset of unilateral visual

Y. Isayama; T. Takahashi; M. Inoue; T. Jimura

1983-01-01

59

Endoscopic endonasal posterior clinoidectomy  

PubMed Central

Background: Posterior clinoidectomy is a useful procedure for maximizing exposure to the interpeduncular cistern via transcranial approaches for basilar tip aneurysms and select intracranial tumors. The value of posterior clinoidectomy during endonasal endoscopic transclival surgery is not well described. Methods: We performed endoscopic endonasal transsphenoidal extradural bilateral posterior clinoidectomy and dorsum sella removal on five silicon-injected cadaveric heads. The dorsum sella was split in the midline and removed from medial to lateral until the posterior clinoids were encountered. The posterior clinoid was dissected from the medial wall of the cavernous sinus and mobilized medially in order to detach it from the ligaments and carefully fractured it from the bony attachment to the petrous apex and carotid canal. Following this, the clival and dorsum sella dura was opened to expose the interpeduncular cistern and its contents. Results: The technical feasibility of endoscopic endonasal extradural posterior clinoidectomy was reproduced in all five cadaveric specimens. This technique was performed without damaging the vital structures, including preservation of the pituitary gland. After performing bilateral posterior clinoidectomy, the retrosellar dura was opened, allowing good visualization of the contents of the prepontine and interpeduncular cistern. Conclusion: We describe the technique of endoscopic endonasal extradural posterior clinoidectomy. We believe this approach is best suited for retrosellar pathology located in the interpeduncular cistern and is a useful adjunct to the transclival approach to increase the field of view and maximize the extent of resection. PMID:22754729

Silva, Danilo; Attia, Moshe; Kandasamy, Jothy; Alimi, Marjan; Anand, Vijay K.; Schwartz, Theodore H.

2012-01-01

60

The canal of the posterior ampullar nerve: an important anatomic landmark in the posterior fossa transmeatal approach  

Microsoft Academic Search

The canal of the posterior ampullar nerve is located between the inferior part of the internal acoustic meatus and ampulla of the posterior semicircular canal. It permits a more accurate localisation of the underlying labyrinth in inner-ear surgery. An anatomical and radiological study was undertaken to determine the importance the relationship between the canal and the labyrinth. Ten dry and

B. V. Agirdir; M. Sindel; G. Arslan; F. B. Yildirim; E. I. Balkan; O. Dinç

2001-01-01

61

Posterior-based confidence measures for spoken term detection   

E-print Network

Confidence measures play a key role in spoken term detection (STD) tasks. The confidence measure expresses the posterior probability of the search term appearing in the detection period, given the speech. Traditional approaches are based...

Wang, Dong; Tejedor, Javier; Frankel, Joe; King, Simon

2009-01-01

62

STABILITY AND INFINITESIMAL ROBUSTNESS OF POSTERIOR DISTRIBUTIONS AND POSTERIOR QUANTITIES  

E-print Network

STABILITY AND INFINITESIMAL ROBUSTNESS OF POSTERIOR DISTRIBUTIONS AND POSTERIOR QUANTITIES revision February, 1998 Abstract Infinitesimal sensitivities of the posterior distribution P (\\DeltajX ) and posterior quantities ae(P ) w.r.t. the choice of the prior P are considered. In a very general setting

Basu, Sanjib

63

Bayesian inference of a lake water quality model by emulating its posterior density  

NASA Astrophysics Data System (ADS)

We use a Gaussian stochastic process emulator to interpolate the posterior probability density of a computationally demanding application of the biogeochemical-ecological lake model BELAMO to accelerate statistical inference of deterministic model and error model parameters. The deterministic model consists of a mechanistic description of key processes influencing the mass balance of nutrients, dissolved oxygen, organic particles, and phytoplankton and zooplankton in the lake. This model is complemented by a Gaussian stochastic process to describe the remaining model bias and by Normal, independent observation errors. A small subsample of the Markov chain representing the posterior of the model parameters is propagated through the full model to get model predictions and uncertainty estimates. We expect this approximation to be more accurate at only slightly higher computational costs compared to using a Normal approximation to the posterior probability density and linear error propagation to the results as we did in an earlier paper. The performance of the two techniques is compared for a didactical example as well as for the lake model. As expected, for the didactical example, the use of the emulator led to posterior marginals of the model parameters that are closer to those calculated by Markov chain simulation using the full model than those based on the Normal approximation. For the lake model, the new technique proved applicable without an excessive increase in computational requirements, but we faced challenges in the choice of the design data set for emulator calibration. As the posterior is a scalar function of the parameters, the suggested technique is an alternative to the emulation of a potentially more complex, structured output of the simulation model that allows for the use of a less case-specific emulator. This is at the cost that still the full model has to be used for prediction (which can be done with a smaller, approximately independent subsample of the Markov chain).

Dietzel, A.; Reichert, P.

2014-10-01

64

Posterior Predictive Inference Sudipto Banerjee  

E-print Network

Posterior Predictive Inference Sudipto Banerjee sudiptob@biostat.umn.edu University of Minnesota Posterior Predictive Inference ­ p. 1/ #12;Posterior Predictive Checks Assume modelling data as y = (y1(T(yrep, ) > T(y, ) | y) = 1 M M t=1 1[T(yt rep, t) > T(y, t)]. Posterior Predictive Inference ­ p. 2/ #12;Model

Carlin, Bradley P.

65

Posterior distribution Andrew Gelman  

E-print Network

Posterior distribution Andrew Gelman Volume 3, pp 1627­1628 in Encyclopedia of Environmetrics (ISBN of the vector of uncertain quantities w1, . . . , wJ, as illustrated in the following matrix: l w1 w2 Ð Ð Ð wJ 1

Gelman, Andrew

66

Posterior Cranial Fossa Meningiomas*  

PubMed Central

This study evaluated the outcomes, complications, and recurrence rates of posterior cranial fossa meningiomas. We retrospectively reviewed our surgical experience with 64 posterior cranial fossa meningiomas. Mean age was 56 years with a female preponderance (67.2%). Headache was the most common symptom. Retrosigmoid approach was the commonest surgical procedure (23.4%). The incidence of cranial nerve related complications was 28%. Postoperatively facial nerve weakness was observed in 11%. The incidence of cerebrospinal fluid leak was 4.6%. Gross total resection was achieved in 37 patients (58%). Sixteen patients (25%) with residual tumors underwent Gamma knife radiosurgery. Recurrence or tumor progression was observed in 12 patients (18.7%). Operative mortality was 3.1%. At their last follow-up, 93% of the cases achieved Glasgow Outcome Scale scores 4 or 5. Total excision is the ideal goal which can be achieved with meningiomas located in certain location, such as lateral convexity, but for other posterior fossa meningiomas the close proximity of critical structures is a major obstacle in achieving this goal. In practicality, a balance between good functional outcome and extent of resection is important for posterior cranial fossa meningiomas in proximity to critical structures. PMID:23372989

Javalkar, Vijayakumar; Banerjee, Anirban Deep; Nanda, Anil

2012-01-01

67

ESTIMATION OF MUSCLE ACTIVITY USING PROBABILITY DENSITY FUNCTIONS  

E-print Network

........................................................................................... 12 2.1 EMG Data Acquisition....................................................................................................... 14 Chapter 3: EMG Posterior Probability Density Function Estimation Using Bayes' Theorem ....................................................... 19 Chapter 4: EMG and Kinematic Data Processing

68

Persistent occiput posterior.  

PubMed

Persistent occiput posterior (OP) is associated with increased rates of maternal and newborn morbidity. Its diagnosis by physical examination is challenging but is improved with bedside ultrasonography. Occiput posterior discovered in the active phase or early second stage of labor usually resolves spontaneously. When it does not, prophylactic manual rotation may decrease persistent OP and its associated complications. When delivery is indicated for arrest of descent in the setting of persistent OP, a pragmatic approach is suggested. Suspected fetal macrosomia, a biparietal diameter above the pelvic inlet or a maternal pelvis with android features should prompt cesarean delivery. Nonrotational operative vaginal delivery is appropriate when the maternal pelvis has a narrow anterior segment but ample room posteriorly, like with anthropoid features. When all other conditions are met and the fetal head arrests in an OP position in a patient with gynecoid pelvic features and ample room anteriorly, options include cesarean delivery, nonrotational operative vaginal delivery, and rotational procedures, either manual or with the use of rotational forceps. Recent literature suggests that maternal and fetal outcomes with rotational forceps are better than those reported in older series. Although not without significant challenges, a role remains for teaching and practicing selected rotational forceps operations in contemporary obstetrics. PMID:25730235

Barth, William H

2015-03-01

69

Asteroidal collision probabilities  

NASA Astrophysics Data System (ADS)

Several past calculations of collision probabilities between pairs of bodies on independent orbits have yielded inconsistent results. We review the methodologies and identify their various problems. Greenberg's (1982) collision probability formalism (now with a corrected symmetry assumption) is equivalent to Wetherill's (1967) approach, except that it includes a way to avoid singularities near apsides. That method shows that the procedure by Namiki and Binzel (1991) was accurate for those cases where singularities did not arise.

Bottke, W. F.; Greenberg, R.

1993-05-01

70

Corneal topography of posterior keratoconus.  

PubMed

Posterior keratoconus is an unusual abnormality of the cornea generally classified as one of the anterior chamber cleavage anomalies. It is characterized clinically by the presence of a circumscribed or generalized corneal thinning with posterior depression of the cornea and is considered distinct from keratoconus. Although patients with posterior keratoconus may have visual complaints clearly related to their abnormal corneas, the surface topography of these corneas has not been studied in detail. Keratometry and photokeratoscopy provide an incomplete picture of the surface geometry of posterior keratoconus. We utilized computer assisted topographic analysis to study the cornea of a patient with posterior keratoconus. The Topographic Modeling System demonstrated that the patient's cornea showed a central steepened "cone" coincident with the area of circumscribed posterior keratoconus as well as paracentral flattening. This report documents the topographic abnormality in this rare disorder. PMID:1424657

Mannis, M J; Lightman, J; Plotnik, R D

1992-07-01

71

An Alternative Version of Conditional Probabilities and Bayes' Rule: An Application of Probability Logic  

ERIC Educational Resources Information Center

This paper presents an alternative version of formulas of conditional probabilities and Bayes' rule that demonstrate how the truth table of elementary mathematical logic applies to the derivations of the conditional probabilities of various complex, compound statements. This new approach is used to calculate the prior and posterior probabilities

Satake, Eiki; Amato, Philip P.

2008-01-01

72

Novel posterior fixation keratoprosthesis  

NASA Astrophysics Data System (ADS)

The keratoprosthesis is the last solution for corneally blind patients that cannot benefit from corneal transplants. Keratoprostheses that have been designed to be affixed anteriorly usually necessitate multi-step surgical procedures and are continuously subjected to the extrusion forces generated by the positive intraocular pressure; therefore, clinical results in patients prove inconsistent. We proposed a novel keratoprosthesis concept that utilizes posterior corneal fixation which `a priori' minimizes the risk of aqueous leakage and expulsion. This prosthesis is implanted in a single procedure thereby reducing the number of surgical complications normally associated with anterior fixation devices. In addition, its novel design makes this keratoprosthesis implantable in phakic eyes. With an average follow-up of 13 months (range 3 to 25 months), our results on 21 cases are encouraging. Half of the keratoprostheses were implanted in severe burn cases, with the remainder in cases of pseudo- pemphigus. Good visual results and cosmetic appearance were obtained in 14 of 21 eyes.

Lacombe, Emmanuel

1992-08-01

73

Posterior Based Keyword Spotting with A Priori Thresholds Hamed Ketabdar, Jithendra Vepa, Samy Bengio and Herve Bourlard  

E-print Network

Posterior Based Keyword Spotting with A Priori Thresholds Hamed Ketabdar, Jithendra Vepa, Samy propose a new posterior based scoring approach for keyword and non keyword (garbage) elements. The estimation of these scores is based on HMM state posterior probability defini- tion, taking into account long

74

Probability Spaces  

NSDL National Science Digital Library

Created by Kyle Siegrist of the University of Alabama-Huntsville, this is an online, interactive lesson on probability spaces. The resource provides examples, exercises, and applets that cover conditional probability, independence, and several modes of convergence that are appropriate for random variables. This section also covers probability space, the paradigm of a random experiment and its mathematical model as well as sample spaces, events, random variables, and probability measures. This is the second of seventeen different statistics lessons provided by Siegrist.

Siegrist, Kyle

75

Experimental Probability  

NSDL National Science Digital Library

This probability application allows the learner to conduct a large volume of experimental trials using a die or an adjustable spinner. Conducting a large volume of trials will enable the learner to make comparisons between experimental and theoretical probability. Discussion topics and a worksheet on experimental probability are provided.

2012-01-01

76

Predictable Probability  

NSDL National Science Digital Library

Probability is used to determine the likeliness of an event. Use these games to test your knowledge of this skill. You can adjust this spinner and determine the probability of the pointer landing in a certain sector. Try picking different colored marbles out of the box and determine the probability of each. Find the prize hidden behind each Door. ...

Ms. Cate

2008-04-23

77

Posterior cortical atrophy: Unique features  

Microsoft Academic Search

Posterior cortical atrophy (PCA) is a visual-cognitive syndrome caused by Creutzfeldt-Jakob disease (CJD), Alzheimer's disease (AD), or subcortical gliosis. We report a case of posterior cortical atrophy unique in (1) comprehensive documentation of clinical, radiologic, electroencephalograph, metabolic and histopathologic findings, (2) repeated clinical and laboratory assessment, and (3) establishment of unique occipital subcortical gliosis in a patient with AD. Clinical

T. Tom; J. L. Cummings; J. Pollak

1998-01-01

78

Epilepsy surgery in the posterior cortex.  

PubMed

Fourteen (74%) of 19 patients obtained a significant reduction in seizures after posterior corticectomy; 6 (32%) were seizure-free over a median follow-up of 3.7 years (range, 1 to 14 years). Surgery included limited resections of the occipital lobe in 16 patients, posterior temporal region in 11, and posterior portion of parietal lobe in 7. Surgical failure related to probable multiple areas of epileptogenesis (4 patients), or limited resections (2 patients) to preserve visual fields (2 patients) and to avoid dyslexia (1 patient). Of 14 patients without a complete hemianopia preoperatively, 6 (43%) developed a new or increased visual field deficit, 2 (14%) of which were hemianopia. Four (36%) of 11 occipital lobe resections resulted in a new or increased visual field deficit: quadrantanopia in 3 and hemianopia in 1. Visual phenomena were the most common initial ictal symptoms, occurring in 13 (68%) of the 19 patients. Twelve patients had complex partial seizures: in 2, always without warning; in 7, always following an aura, usually visual; and in 3 patients, with or without warning. Scalp electroencephalography identified the origin of most recorded seizures in 12 (63%) of the 19 patients. A principal interictal spike focus appeared in 15 patients (79%), and always correlated with the epileptogenic lobe as defined by scalp and/or subdural-recorded seizures (14 patients) or by clinical analysis and computed tomography (1 patient). PMID:1892366

Blume, W T; Whiting, S E; Girvin, J P

1991-06-01

79

Naive Probability: A Mental Model Theory of Extensional Reasoning.  

ERIC Educational Resources Information Center

Outlines a theory of naive probability in which individuals who are unfamiliar with the probability calculus can infer the probabilities of events in an "extensional" way. The theory accommodates reasoning based on numerical premises, and explains how naive reasoners can infer posterior probabilities without relying on Bayes's theorem. (Author/GCP)

Johnson-Laird, P. N.; Legrenzi, Paolo; Girotto, Vittorio; Legrenzi, Maria Sonino; Caverni, Jean-Paul

1999-01-01

80

Conditional Probability  

NSDL National Science Digital Library

This site, created by the Department of Statistics at Yale University gives an explanation, a definition and an example of conditional probability. Topics include the probabilities of intersections of events and Bayes' formula. Overall, this is a great resource for any mathematics classroom studying statistics.

Lacey, Michelle

81

Probability Calculator  

NSDL National Science Digital Library

This tool lets you calculate the probability that a random variable X is in a specified range, for a variety of probability distributions for X: the normal distribution, the binomial distribution with parameters n and p, the chi-square distribution, the exponential distribution, the geometric distribution, the hypergeometric distribution, the negative binomial distribution, the Poisson distribution, and Student's t-distribution. The first choice box lets you select a probability distribution. Depending on the distribution you select, text areas will appear for you to enter the values of the parameters of the distribution. Parameters that are probabilities (e.g., the chance of success in each trial for a binomial distribution) can be entered either as decimal numbers between 0 and 1, or as percentages. If you enter a probability as a percentage, be sure to include the percent sign (%) after the number.

Stark, Philip B.

82

Posterior Tibial Tendon Dysfunction (PTTD)  

MedlinePLUS

... ACFAS | Información en Español Advanced Search Home » Foot & Ankle Conditions » Posterior Tibial Tendon Dysfunction (PTTD) Text Size ... the arch, and an inward rolling of the ankle. As the condition progresses, the symptoms will change. ...

83

Posterior skull surgery in craniosynostosis  

Microsoft Academic Search

In 1984, two young infants with unusual “clover-leaf” patterns of skull deformity were treated by posterior skull-releasing surgery that dramatically improved their overall skull shape, to the extent that further operative intervention was not required. This focused our attention on the posterior skull and its role in craniosynostosis. In cases of multi-suture craniosynostosis and craniofacial syndromes severely raised intracranial pressure

S. Sgouros; J. H. Goldin; A. D. Hockley; M. J. C. Wake

1996-01-01

84

Plinko Probability  

NSDL National Science Digital Library

The students will play a classic game from a popular show. Through this they will see the probabilty that the ball will land each of the numbers with more accurate results coming from repeated testing.

PhET at University of Colorado

2010-08-02

85

Posterior crossbite - treatment and stability  

PubMed Central

Posterior crossbite is defined as an inadequate transversal relationship of maxillary and mandibular teeth. Even when eliminating the etiologic factors, this malocclusion does not have a spontaneous correction, and should be treated with maxillary expansion as early as possible. This treatment aims at providing a better tooth/skeletal relationship, thereby improving masticatory function, and establishing a symmetrical condyle/fossa relationship. Should posterior crossbite not be treated early, it may result in skeletal changes, demanding a more complex approach. Additionally, an overcorrection expansion protocol should be applied in order to improve the treatment stability. Although the literature has reported a high rate of relapse after maxillary expansion, the goal of this study was to demonstrate excellent stability of the posterior crossbite correction 21 years post treatment. PMID:22666850

de ALMEIDA, Renato Rodrigues; de ALMEIDA, Marcio Rodrigues; OLTRAMARI-NAVARRO, Paula Vanessa Pedron; CONTI, Ana Cláudia de Castro Ferreira; NAVARRO, Ricardo de Lima; MARQUES, Henry Victor Alves

2012-01-01

86

Pig Data and Bayesian Inference on Multinomial Probabilities  

ERIC Educational Resources Information Center

Bayesian inference on multinomial probabilities is conducted based on data collected from the game Pass the Pigs[R]. Prior information on these probabilities is readily available from the instruction manual, and is easily incorporated in a Dirichlet prior. Posterior analysis of the scoring probabilities quantifies the discrepancy between empirical…

Kern, John C.

2006-01-01

87

Primary myelolipoma in posterior mediastinum  

PubMed Central

Myelolipoma in posterior mediastinum is indeed rare. As a benign tumor, it consists of mature fat with scattered foci of haematopoietic elements resembling bone marrow. The computed tomography (CT) and magnetic resonance imaging (MRI) are effective methods to detect them, while the definite diagnosis still depends on pathological diagnosis. Up to now, there is no standard treatment for this disease. Surgery is thought to be the best choice in some literatures reports. In this paper, two patients with primary posterior mediastinal tumor are reported, both of whom were underwent Video-assisted thoracoscopic surgery (VATS). Postoperative pathological diagnosis was myelolipoma. PMID:25276393

Xiong, Yan; Wang, Yong

2014-01-01

88

Pleasant Probability  

NSDL National Science Digital Library

Have fun using different probability techniques to find answers to questions. Have fun figuring out the odds of rolling a specific number with dice! What are your Chances? What are your Chances? Make up your own experiment and list the results here! Bar Graph Chart Bar Graph Chart Figure out the answer to the experiment by using a circle graph. Adjustable Spinner Adjustable Spinner ...

Ms. Barlow

2006-11-14

89

Exploring Probability  

NSDL National Science Digital Library

This interactive mathematics resource allows the user to explore the outcomes resulting from tossing a coin, rolling a die, and using a spinner to perform single and double event probabilities. The resource includes print activities, solutions, learning strategies, and a board game.

2003-01-01

90

Probability Clouds  

NSDL National Science Digital Library

The modern view of an atom consists of a nucleus made from protons and neutrons with electrons surrounding it in regions of high probability called orbitals. In this activity, students build computer models of atoms by adding and removing electrons, protons, and neutrons.

2012-07-19

91

Probability Sampling  

NSDL National Science Digital Library

This site, created by author William M.K. Trochim, describes in detail five different types of random sampling. Some of these types include: simple random, stratified random, systematic random, cluster random, multi-stage sampling. The author provides examples, definitions, and the procedures behind the methods. Overall, this site provides a nice overview of probability sampling.

Trochim, William M.K.

92

The Neuropsychiatric Profile of Posterior Cortical Atrophy.  

PubMed

We analyzed scores obtained at the Neuropsychiatric Inventory (NPI) by 20 patients with posterior cortical atrophy (PCA) and contrasted it with 20 patients having Alzheimer disease (AD). Patients with hallucinations and delusions were not included due to the high probability of a diagnosis of Lewy body disease. Prevalence of behavioral and psychological symptoms (BPSD) was 95% in the PCA group, the most frequent being apathy and anxiety. Cluster analysis on NPI subscales highlighted a behavioral subsyndrome characterized by agitated temper and irritability. Depression, anxiety, and apathy did not cluster with any other BPSD nor with each other. The PCA group showed a significantly higher proportion of anxious patients and worse anxiety score than patients with AD. No correlation was found between NPI data and demographic, clinical, or neuropsychological features nor were there significant differences for the same variables between anxious and nonanxious cases with PCA. In agreement with anecdotal reports, anxiety seems particularly relevant in PCA. PMID:25330926

Isella, Valeria; Villa, Giulia; Mapelli, Cristina; Ferri, Francesca; Appollonio, Ildebrando Marco; Ferrarese, Carlo

2014-10-20

93

Journal of Artificial Intelligence Research 39 (2010) 1-37 Submitted 10/09; published 08/10 Active Tuples-based Scheme for Bounding Posterior Beliefs  

E-print Network

Tuples-based Scheme for Bounding Posterior Beliefs Bozhena Bidyuk bbidyuk@google.com Google Inc. 19540 Abstract The paper presents a scheme for computing lower and upper bounds on the posterior marginals that bounds the probability of evidence or posterior marginals and enhance its performance in an anytime

Dechter, Rina

94

Journal of Artificial Intelligence Research 39 (2010) 335-371 Submitted 10/09; published 09/10 Active Tuples-based Scheme for Bounding Posterior Beliefs  

E-print Network

/10 Active Tuples-based Scheme for Bounding Posterior Beliefs Bozhena Bidyuk bbidyuk@google.com Google Inc Abstract The paper presents a scheme for computing lower and upper bounds on the posterior marginals that bounds the probability of evidence or posterior marginals and enhance its performance in an anytime

Dechter, Rina

95

Unilateral posterior crossbite and mastication  

Microsoft Academic Search

ObjectiveThis study was designed to characterize masticatory-cycle morphology, and distance of the contact glide in the closing masticatory stroke, in adult subjects with uncorrected unilateral posterior crossbite (UPXB), comparing the results obtained with those obtained in a parallel group of normal subjects.

Benito Rilo; José Luis da Silva; María Jesús Mora; Carmen Cadarso-Suárez; Urbano Santana

2007-01-01

96

Multiple model cardinalized probability hypothesis density filter  

NASA Astrophysics Data System (ADS)

The Probability Hypothesis Density (PHD) filter propagates the first-moment approximation to the multi-target Bayesian posterior distribution while the Cardinalized PHD (CPHD) filter propagates both the posterior likelihood of (an unlabeled) target state and the posterior probability mass function of the number of targets. Extensions of the PHD filter to the multiple model (MM) framework have been published and were implemented either with a Sequential Monte Carlo or a Gaussian Mixture approach. In this work, we introduce the multiple model version of the more elaborate CPHD filter. We present the derivation of the prediction and update steps of the MMCPHD particularized for the case of two target motion models and proceed to show that in the case of a single model, the new MMCPHD equations reduce to the original CPHD equations.

Georgescu, Ramona; Willett, Peter

2011-09-01

97

Accuracy Enhancement for Fingerprint-Based WLAN Indoor Probability Positioning Algorithm  

Microsoft Academic Search

This paper proposed an accuracy enhancement for fingerprint-based WLAN indoor probability positioning algorithm. Based on Bayes' probability theory, the traditional probability positioning algorithm converts the new sample location coordinates corresponding to the posterior probability to a priori marginal probability, which leads to the reference point having the greatest product for the estimated location as the terminal coordinates. However, due to

Ma Lin; Xu Yubin; Zhou Mu

2010-01-01

98

Posterior cruciate ligament (PCL) injury - aftercare  

MedlinePLUS

... of tissue that connects bone to bone. The posterior cruciate ligament (PCL) is located inside your knee ... Curtis C, Bienkowski P, Micheli LJ. Posterior cruciate ligament ... of Physical Medicine and Rehabilitation. 2nd ed. St. Louis, ...

99

Nanotherapy for posterior eye diseases.  

PubMed

It is assumed that more than 50% of the most enfeebling ocular diseases have their origin in the posterior segment. Furthermore, most of these diseases lead to partial or complete blindness, if left untreated. After cancer, blindness is the second most dreaded disease world over. However, treatment of posterior eye diseases is more challenging than the anterior segment ailments due to a series of anatomical barriers and physiological constraints confronted for delivery to this segment. In this regard, nanostructured drug delivery systems are proposed to defy ocular barriers, target retina, and act as permeation enhancers in addition to providing a controlled release. Since an important step towards developing effective treatment strategies is to understand the course or a route a drug molecule needs to follow to reach the target site, the first part of the present review discusses various pathways available for effective delivery to and clearance from the posterior eye. Promise held by nanocarrier systems, viz. liposomes, nanoparticles, and nanoemulsion, for effective delivery and selective targeting is also discussed with illustrative examples, tables, and flowcharts. However, the applicability of these nanocarrier systems as self-administration ocular drops is still an unrealized dream which is in itself a huge technological challenge. PMID:24862316

Kaur, Indu Pal; Kakkar, Shilpa

2014-11-10

100

Cerebellar medulloblastoma: the importance of posterior fossa dose to survival and patterns of failure  

SciTech Connect

Fifty patients with biopsy-proven cerebellar medulloblastoma were retrospectively analyzed for prognostic factors, survival and patterns of failure. Five- and ten-year actuarial survivals for the entire group were 51% and 42%. Survival and local control were significantly better for the 21 patients who received doses greater that 5000 rad to the posterior fossa (85% and 80% respectively) than for the remaining patients (38% and 38%, respectively). Significant prognostic factors included achievement of local control in the posterior fossa (p = .0001) and dose to the posterior fossa (p = .0005). Sex, age, duration of symptoms, extent of surgery and initial T-stage of disease were not significant. Posterior fossa was the predominant site of failure (71% of failures), but 10% of patients failed in the cerebrum and 12% outside the CNS. This experience confirms that survival rates of 70-80% are achievable with current treatment policies but accurate and consistent dose delivery to the posterior fossa is essential.

Silverman, C.L.; Simpson, J.R.

1982-11-01

101

Cerebellar medulloblastoma: the importance of posterior fossa dose to survival and patterns of failure  

SciTech Connect

Fifty patients with biopsy-proven cerebellar medulloblastoma were retrospectively analyzed for prognostic factors, survival and patterns of failure. Five- and ten-year actuarial survivals for the entire group were 51% and 42%. Survival and local control were significantly better for the 21 patients who received doses greater than 5000 rad to the posterior fossa (85% and 80% respectively) than for the remaining patients (38% and 38%, respectively). Significant prognostic factors included achievement of local control in the posterior fossa (p = .0001) and dose to the posterior fossa (p = .0005). Sex, age, duration of symptoms, extent of surgery and initial T-stage of disease were not significant. Posterior fossa was the predominant site of failure (71% of failures), but 10% of patients failed in the cerebrum and 12% outside the CNS. This experience confirms that survival rates of 70-80% are achievable with current treatment policies but accurate and consistent dose delivery to the posterior fossa is essential.

Silverman, C.L.; Simpson, J.R.

1982-11-01

102

Isolated posterior cruciate ligament injuries in athletes  

Microsoft Academic Search

The literature is divided as to the necessity of an intact posterior cruciate ligament for functional stability. Pre sented here is a prospective study of isolated posterior cruciate injuries seen in the acute stage in 13 patients, 6 males and 7 females. The diagnosis of posterior cruciate ligament tear was made clinically and con firmed by arthroscopy. The average age

P. J. Fowler; S. S. Messieh

1987-01-01

103

Posterior Integration in Dynamic Models Peter Mueller  

E-print Network

Posterior Integration in Dynamic Models Peter Mueller Institute of Statistics & Decision Sciences of posterior distributions corresponding to the subsequent stages of the dynamic model. In the absence of these posterior distri­ butions. This paper reviews some previously suggested Monte Carlo based algorithms

West, Mike

104

Posterior Implementation vs Ex-Post Implementation  

E-print Network

Posterior Implementation vs Ex-Post Implementation by Philippe Jehiel, Moritz Meyer-ter-Vehn, Benny Moldovanu and William R. Zame1 This version: 1.9.2006 In this short note we discuss how posterior, posterior implemen- tation is de...ned with respect to the information released by the mechanism

Franz, Sven Oliver

105

Visualizing highdimensional posterior distributions in Bayesian modeling  

E-print Network

Visualizing high­dimensional posterior distributions in Bayesian modeling Jarkko Venna and Samuel on the posterior distribution of the model parameters. The closed­form solution is seldom known and samples of the posterior have to be computed with Markov Chain Monte Carlo (MCMC) methods. The problem is that for large

Kaski, Samuel

106

UNIFORM STABILITY OF POSTERIORS Sanjib Basu  

E-print Network

UNIFORM STABILITY OF POSTERIORS by Sanjib Basu Northern Illinois University DeKalb, IL 60115, USA E­mail: basu@niu.edu Abstract Infinitesimal sensitivities of the posterior distribution P (\\DeltajX ) and posterior quantities ae(P ) w.r.t. the choice of the prior P are considered. In a very general setting

Basu, Sanjib

107

Consistency of Posterior Distributions for Neural Networks  

E-print Network

Consistency of Posterior Distributions for Neural Networks Herbert Lee \\Lambda May 21, 1998 Abstract In this paper we show that the posterior distribution for feedforward neural networks is asymp problem, then uses bounds on the bracketing entropy to show that the posterior is consistent over

108

Introduction In normal eyes, the posterior corneal  

E-print Network

Introduction In normal eyes, the posterior corneal aberration has a relatively small impact. However, in keratoconic eyes, contribution of the posterior corneal aberration to the total ocular aberration can also be compensated by the posterior corneal aberration. The goal of this study

Yoon, Geunyoung

109

CONCENTRATION OF POSTERIOR DISTRIBUTIONS WITH MISSPECIFIED MODELS  

E-print Network

CONCENTRATION OF POSTERIOR DISTRIBUTIONS WITH MISSPECIFIED MODELS Christophe ABRAHAMa and Benoît investigate the asymptotic properties of posterior distributions when the model is misspecified, i the asymptotic of the posterior distribution when the model is correctly specified i.e. q is equal to h for some

Boyer, Edmond

110

The feature-based posterior crown design in a dental CAD\\/CAM system  

Microsoft Academic Search

This paper presents a newly developed CAD approach for a quick and accurate design of a dental posterior prosthesis. The approach\\u000a arises from the basic idea that every human tooth has its own specific features. Based upon the features of the standard posterior\\u000a tooth, the initial data containing the defined feature points are firstly acquired from the scanned points of

Ya-Li Song; Jia Li; Ling Yin; Tian Huang; Ping Gao

2007-01-01

111

Posterior consistency for Bayesian inverse problems through stability and regression results  

NASA Astrophysics Data System (ADS)

In the Bayesian approach, the a priori knowledge about the input of a mathematical model is described via a probability measure. The joint distribution of the unknown input and the data is then conditioned, using Bayes’ formula, giving rise to the posterior distribution on the unknown input. In this setting we prove posterior consistency for nonlinear inverse problems: a sequence of data is considered, with diminishing fluctuations around a single truth and it is then of interest to show that the resulting sequence of posterior measures arising from this sequence of data concentrates around the truth used to generate the data. Posterior consistency justifies the use of the Bayesian approach very much in the same way as error bounds and convergence results for regularization techniques do. As a guiding example, we consider the inverse problem of reconstructing the diffusion coefficient from noisy observations of the solution to an elliptic PDE in divergence form. This problem is approached by splitting the forward operator into the underlying continuum model and a simpler observation operator based on the output of the model. In general, these splittings allow us to conclude posterior consistency provided a deterministic stability result for the underlying inverse problem and a posterior consistency result for the Bayesian regression problem with the push-forward prior. Moreover, we prove posterior consistency for the Bayesian regression problem based on the regularity, the tail behaviour and the small ball probabilities of the prior.

Vollmer, Sebastian J.

2013-12-01

112

Posterior subcapsular cataract in Degos disease  

Microsoft Academic Search

PURPOSE: To report an association of posterior subcapsular cataract with Degos disease.METHOD: Case report of a 42-year-old man.RESULTS: A posterior subcapsular cataract developed in the patient’s left eye at age 43 years, 1 year before his death. The diagnosis of Degos disease was confirmed pathologically by skin biopsy and at necropsy.CONCLUSION: Posterior subcapsular cataract may be associated with Degos disease

Robert Egan; Simmons Lessell

2000-01-01

113

Minimally Invasive Posterior Hamstring Harvest  

PubMed Central

Autogenous hamstring harvesting for knee ligament reconstruction is a well-established standard. Minimally invasive posterior hamstring harvest is a simple, efficient, reproducible technique for harvest of the semitendinosus or gracilis tendon or both medial hamstring tendons. A 2- to 3-cm longitudinal incision from the popliteal crease proximally, in line with the semitendinosus tendon, is sufficient. The deep fascia is bluntly penetrated, and the tendon or tendons are identified. Adhesions are dissected. Then, an open tendon stripper is used to release the tendon or tendons proximally; a closed, sharp tendon stripper is used to release the tendon or tendons from the pes. Layered, absorbable skin closure is performed, and the skin is covered with a skin sealant, bolster dressing, and plastic adhesive bandage for 2 weeks. PMID:24266003

Wilson, Trent J.; Lubowitz, James H.

2013-01-01

114

Posterior Lamellar Keratoplasty in Perspective  

Microsoft Academic Search

\\u000a \\u000a \\u000a \\u000a \\u000a \\u000a • \\u000a \\u000a \\u000a Posterior lamellar keratoplasty (PLK) offers many substantial benefits compared to penetrating keratoplasty (PK) including:\\u000a closed eye surgery elimination of both regular and irregular postoperative astigmatism leading to full visual rehabilitation\\u000a with spectacles within 3–6 months, elimination of postoperative corneal anaesthesia, and a reduced risk of postoperative globe\\u000a rupture.\\u000a \\u000a \\u000a \\u000a \\u000a • \\u000a \\u000a \\u000a Disadvantages of PLK compared to PK include: corneal stromal scarring

F Arnalich-Montiel; JKG Dart

115

Multinomial mixture model with heterogeneous classification probabilities  

USGS Publications Warehouse

Royle and Link (Ecology 86(9):2505-2512, 2005) proposed an analytical method that allowed estimation of multinomial distribution parameters and classification probabilities from categorical data measured with error. While useful, we demonstrate algebraically and by simulations that this method yields biased multinomial parameter estimates when the probabilities of correct category classifications vary among sampling units. We address this shortcoming by treating these probabilities as logit-normal random variables within a Bayesian framework. We use Markov chain Monte Carlo to compute Bayes estimates from a simulated sample from the posterior distribution. Based on simulations, this elaborated Royle-Link model yields nearly unbiased estimates of multinomial and correct classification probability estimates when classification probabilities are allowed to vary according to the normal distribution on the logit scale or according to the Beta distribution. The method is illustrated using categorical submersed aquatic vegetation data. ?? 2010 Springer Science+Business Media, LLC.

Holland, M.D.; Gray, B.R.

2011-01-01

116

Endovascular treatment of posterior circulation aneurysms.  

PubMed

Endovascular techniques are well suited for the treatment of posterior circulation aneurysms. This review describes the endovascular management of these aneurysms and discusses relevant technical advances. PMID:24617934

Eller, Jorge L; Dumont, Travis M; Mokin, Maxim; Sorkin, Grant C; Levy, Elad I; Snyder, Kenneth V; Nelson Hopkins, L; Siddiqui, Adnan H

2014-04-01

117

Non-Gaussian Posteriors arising from Marginal Detections  

E-print Network

We show that in cases of marginal detections (~ 3\\sigma), such as that of Baryonic Acoustic Oscillations (BAO) in cosmology, the often-used Gaussian approximation to the full likelihood is very poor, especially beyond ~3\\sigma. This can radically alter confidence intervals on parameters and implies that one cannot naively extrapolate 1\\sigma-errorbars to 3\\sigma, and beyond. We propose a simple fitting formula which corrects for this effect in posterior probabilities arising from marginal detections. Alternatively the full likelihood should be used for parameter estimation rather than the Gaussian approximation of a just mean and an error.

Bruce A. Bassett; Niayesh Afshordi

2012-03-16

118

Posterior Cruciate Ligament Removal Contributes to Abnormal Knee Motion during Posterior Stabilized Total Knee Arthroplasty  

E-print Network

Posterior Cruciate Ligament Removal Contributes to Abnormal Knee Motion during Posterior Stabilized Total Knee Arthroplasty Melinda J. Cromie,1,2 Robert A. Siston,1,2,3,4 Nicholas J. Giori,2,5 Scott L (20­608) following posterior stabilized total knee arthroplasty. The underlying biomechanical causes

Delp, Scott

119

14 CFR 417.224 - Probability of failure analysis.  

Code of Federal Regulations, 2014 CFR

...probability in a consistent manner. A launch vehicle failure probability estimate must use accurate data, scientific principles, and a method that is statistically or probabilistically valid. For a launch vehicle with fewer than two...

2014-01-01

120

14 CFR 417.224 - Probability of failure analysis.  

Code of Federal Regulations, 2012 CFR

...probability in a consistent manner. A launch vehicle failure probability estimate must use accurate data, scientific principles, and a method that is statistically or probabilistically valid. For a launch vehicle with fewer than two...

2012-01-01

121

14 CFR 417.224 - Probability of failure analysis.  

Code of Federal Regulations, 2010 CFR

...probability in a consistent manner. A launch vehicle failure probability estimate must use accurate data, scientific principles, and a method that is statistically or probabilistically valid. For a launch vehicle with fewer than two...

2010-01-01

122

14 CFR 417.224 - Probability of failure analysis.  

Code of Federal Regulations, 2013 CFR

...probability in a consistent manner. A launch vehicle failure probability estimate must use accurate data, scientific principles, and a method that is statistically or probabilistically valid. For a launch vehicle with fewer than two...

2013-01-01

123

14 CFR 417.224 - Probability of failure analysis.  

Code of Federal Regulations, 2011 CFR

...probability in a consistent manner. A launch vehicle failure probability estimate must use accurate data, scientific principles, and a method that is statistically or probabilistically valid. For a launch vehicle with fewer than two...

2011-01-01

124

Nonoperatively treated isolated posterior cruciate ligament injuries  

Microsoft Academic Search

To evaluate the theory that isolated posterior cruciate ligament injuries do well when treated nonoperatively, we reviewed 40 patients (mean age, 33 years at fol lowup ; average interval from injury, 6 years) who com pleted a modified Noyes knee questionnaire and were reevaluated by physical examination, radiographs, and isokinetic testing. Thirty of the injuries to the posterior cruciate ligament

Paul M. Keller; K. Donald Shelbourne; John R. McCarroll; Arthur C. Rettig

1993-01-01

125

Visualizing the emergence of posterior cortical atrophy  

Microsoft Academic Search

Posterior cortical atrophy (PCA) is a neurodegenerative condition characterized by a progressive loss of visual processing skills and other posterior functions. Diagnosis is often delayed in PCA as symptoms can be difficult for the patient to articulate and for the clinician to detect. Diagnosis is particularly challenging in the earliest stages of the disease since visual symptoms are often mistaken

Jonathan Kennedy; Manja Lehmann; Magdalena J. Sokolska; Hilary Archer; Elizabeth K. Warrington; Nick C. Fox; Sebastian J. Crutch

2012-01-01

126

Visualizing the emergence of posterior cortical atrophy  

Microsoft Academic Search

Posterior cortical atrophy (PCA) is a neurodegenerative condition characterized by a progressive loss of visual processing skills and other posterior functions. Diagnosis is often delayed in PCA as symptoms can be difficult for the patient to articulate and for the clinician to detect. Diagnosis is particularly challenging in the earliest stages of the disease since visual symptoms are often mistaken

Jonathan Kennedy; Manja Lehmann; Magdalena J. Sokolska; Hilary Archer; Elizabeth K. Warrington; Nick C. Fox; Sebastian J. Crutch

2011-01-01

127

Cerebral Palsy Spasticity. Selective Posterior Rhizotomy  

Microsoft Academic Search

We have performed selective posterior rhizotomies on 60 children with cerebral palsy. The procedure involves lumbar laminectomy with stimulation of the rootlets (fascicles) of the second lumbar to the first sacral posterior roots bilaterally; those rootlets associated with an abnormal motor response, as evidenced by sustained or diffused muscular contraction, are divided leaving intact rootlets associated with a brief localized

Warwick J. Peacock; Leila J. Arens; Barbara Berman

1987-01-01

128

[Posterior epispadias with unknown complete duplicated urethra].  

PubMed

The authors report a case of posterior epispadias associated with complete ventral urethra only discovered during the urethroplasty phase of the operation. This malformation is a rare form of urethral duplication and should be considered in any case of apparently isolated posterior epispadias. PMID:1302070

Aubert, D; Rigaud, P; Destuynder, O; Zoupanos, G

1992-04-01

129

Probability mapping of contaminants  

SciTech Connect

Exhaustive characterization of a contaminated site is a physical and practical impossibility. Descriptions of the nature, extent, and level of contamination, as well as decisions regarding proposed remediation activities, must be made in a state of uncertainty based upon limited physical sampling. The probability mapping approach illustrated in this paper appears to offer site operators a reasonable, quantitative methodology for many environmental remediation decisions and allows evaluation of the risk associated with those decisions. For example, output from this approach can be used in quantitative, cost-based decision models for evaluating possible site characterization and/or remediation plans, resulting in selection of the risk-adjusted, least-cost alternative. The methodology is completely general, and the techniques are applicable to a wide variety of environmental restoration projects. The probability-mapping approach is illustrated by application to a contaminated site at the former DOE Feed Materials Production Center near Fernald, Ohio. Soil geochemical data, collected as part of the Uranium-in-Soils Integrated Demonstration Project, have been used to construct a number of geostatistical simulations of potential contamination for parcels approximately the size of a selective remediation unit (the 3-m width of a bulldozer blade). Each such simulation accurately reflects the actual measured sample values, and reproduces the univariate statistics and spatial character of the extant data. Post-processing of a large number of these equally likely statistically similar images produces maps directly showing the probability of exceeding specified levels of contamination (potential clean-up or personnel-hazard thresholds).

Rautman, C.A.; Kaplan, P.G. [Sandia National Labs., Albuquerque, NM (United States); McGraw, M.A. [Univ. of California, Berkeley, CA (United States); Istok, J.D. [Oregon State Univ., Corvallis, OR (United States); Sigda, J.M. [New Mexico Inst. of Mining and Technology, Socorro, NM (United States)

1994-04-01

130

Validation of Bayesian posterior distributions using a multidimensional Kolmogorov--Smirnov test  

E-print Network

We extend the Kolmogorov--Smirnov (K-S) test to multiple dimensions by suggesting a $\\mathbb{R}^n \\rightarrow [0,1]$ mapping based on the probability content of the highest probability density region of the reference distribution under consideration; this mapping reduces the problem back to the one-dimensional case to which the standard K-S test may be applied. The universal character of this mapping also allows us to introduce a simple, yet general, method for the validation of Bayesian posterior distributions of any dimensionality. This new approach goes beyond validating software implementations; it provides a sensitive test for all assumptions, explicit or implicit, that underlie the inference. In particular, the method assesses whether the inferred posterior distribution is a truthful representation of the actual constraints on the model parameters. We illustrate our multidimensional K-S test by applying it to a simple two-dimensional Gaussian toy problem, and demonstrate our method for posterior validat...

Harrison, Diana; Carvalho, Pedro; Hobson, Michael

2014-01-01

131

Adaptive approximation of higher order posterior statistics  

SciTech Connect

Filtering is an approach for incorporating observed data into time-evolving systems. Instead of a family of Dirac delta masses that is widely used in Monte Carlo methods, we here use the Wiener chaos expansion for the parametrization of the conditioned probability distribution to solve the nonlinear filtering problem. The Wiener chaos expansion is not the best method for uncertainty propagation without observations. Nevertheless, the projection of the system variables in a fixed polynomial basis spanning the probability space might be a competitive representation in the presence of relatively frequent observations because the Wiener chaos approach not only leads to an accurate and efficient prediction for short time uncertainty quantification, but it also allows to apply several data assimilation methods that can be used to yield a better approximate filtering solution. The aim of the present paper is to investigate this hypothesis. We answer in the affirmative for the (stochastic) Lorenz-63 system based on numerical simulations in which the uncertainty quantification method and the data assimilation method are adaptively selected by whether the dynamics is driven by Brownian motion and the near-Gaussianity of the measure to be updated, respectively.

Lee, Wonjung, E-mail: leew@maths.ox.ac.uk

2014-02-01

132

Conditional Probability and Probability of Simultaneous Events  

NSDL National Science Digital Library

This lesson is designed to further students' practice with probability as well as introduce them to conditional probability and probabilities of simultaneous independent events. The lesson provides links to discussions and activities related to conditional and simultaneous probabilities as well as suggested ways to integrate them into the lesson. Finally, this lesson provides links to follow-up lessons designed for use in succession with this one.

2010-01-01

133

Action-intentional spatial bias in a patient with Posterior Cortical Atrophy  

Microsoft Academic Search

Patients without sensory neglect might demonstrate a spatial deviation when drawing. To better understand the mechanism of this deviation, we examined a 61-year-old woman with probable posterior cortical atrophy (PCA) who on imaging showed right hemisphere atrophy and dysfunction. When drawing a clock she correctly made a circle, but when writing the numbers deviated to the left. A blindfolded midsagittal

Matthew L. Cohen; Brandon Burtis; Jay Cheol Kwon; John Williamson; Kenneth M. Heilman

2010-01-01

134

POSTERIOR-BASED CONFIDENCE MEASURES FOR SPOKEN TERM DETECTION , Javier Tejedor1,2  

E-print Network

Frankel1 , Simon King1 and Jose Col´as2 1. The Centre for Speech Technology Research, University of Edinburgh, UK 2. Human Computer Technology Laboratory, Escuela Politecnica Superior, Universidad Autonoma de, confidence measure, posterior probabilities, MLP 1. INTRODUCTION We adopt the definition of the spoken term

Edinburgh, University of

135

Accurately determining inflationary perturbations  

E-print Network

Cosmic microwave anisotropy satellites promise extremely accurate measures of the amplitude of perturbations in the universe. We use a numerical code to test the accuracy of existing approximate expressions for the amplitude of perturbations produced by single-field inflation models. We find that the second-order Stewart-Lyth calculation gives extremely accurate results, typically better than one percent. We use our code to carry out an expansion about the general power-law inflation solution, providing a fitting function giving results of even higher accuracy.

Andrew R Liddle; Ian J Grivell

1997-01-08

136

Alien hand syndrome in left posterior stroke.  

PubMed

Alien hand syndrome is a rare neurological disorder characterized by involuntary and uncontrollable motor behaviour, usually of an arm or hand. The patient perceives the affected limb as alien, and may personify it. The case of a 61-year-old right-handed woman who developed right posterior AHS after ischaemic stroke in the left posterior cerebral artery territory is reported. Neuroimaging studies disclosed no frontal or parietal involvement, while a posterior thalamic lesion was detected. A possible role of the thalamus in the genesis of AHS is discussed. PMID:21327399

Bartolo, Michelangelo; Zucchella, C; Pichiecchio, A; Pucci, E; Sandrini, G; Sinforiani, E

2011-06-01

137

Passionate About Probability  

NSDL National Science Digital Library

In this probability unit plan, three lessons guide students through the use of probability vocabulary, displaying probability on a number line, writing probability as a fraction, and making predictions based on probability. The unit begins with students learning and applying new vocabulary to the book "Probably Pistachio" by Stuart J. Murphy. In lesson two students use dice, spinners, and real life events to write probability as fractions and make predictions based on these fractions, while still using the probability vocabulary. The third lesson includes another probability experiment and a summative assessment. All student worksheet are included with answer keys in PDF format.

Jeanine Pearce

2009-01-01

138

Practice with Probability  

NSDL National Science Digital Library

This set of probability lesson plans includes a variety of activities that engage students and reinforce the concepts of probability. Through these lessons students play a traditional Native American Stick game, they read Probably Pistachio, by Stuart J. Murphy, and they demonstrate probability with probability bags and dice. Included in this resource is teacher background information, student worksheets (pdf), and extension suggestions.

2004-10-15

139

A fast and accurate \\  

Microsoft Academic Search

We present a new ldquoshoeboxrdquo room acoustics simulator that is designed to support research into signal processing algorithms that are robust to reverberation. It is an improvement over existing room acoustics simulators because it is computationally fast, portable to many kinds of research environments, and flexible to use. The proposed simulator is also perceptually accurate because it models both specular

Steven M. Schimmel; Martin F. Müller; Norbert Dillier

2009-01-01

140

POSTERIOR CONSISTENCY IN NONPARAMETRIC REGRESSION PROBLEMS UNDER GAUSSIAN PROCESS PRIORS  

E-print Network

POSTERIOR CONSISTENCY IN NONPARAMETRIC REGRESSION PROBLEMS UNDER GAUSSIAN PROCESS PRIORS By Taeryon Choi and Mark J. Schervish Carnegie Mellon University Posterior consistency can be thought processes. In this paper, we study posterior consistency in nonparametric regression problems using Gaussian

141

Shining a light on posterior cortical atrophy Sebastian J. Crutcha  

E-print Network

Shining a light on posterior cortical atrophy Sebastian J. Crutcha , Jonathan M. Schotta , Gil D Posterior cortical atrophy (PCA) is a clinicoradiologic syndrome characterized by progressive de- cline; Posterior cortical atrophy; Atypical dementia; Simultanagnosia; Visual disturbances; Differential diagnosis

Dickerson, Brad

142

Use of an aiming device in posterior atlantoaxial transarticular screw fixation. Technical note.  

PubMed

Posterior atlantoaxial transarticular screw fixation is an excellent procedure associated with high fusion rates. There is, however, the potential risk of vertebral artery (VA) injury. The authors designed a special aiming device that allows a cannulated screw to be inserted accurately in the most posterior part of the C1-2 joint via the most posterior and medial part of the isthmus of C-2; this screw pathway most safely avoids VA injury. The instruments include an aiming device and a flexible screw-inserting system. The tip of the aiming device is placed on the ridge of the C-2 isthmus just posterior to the atlantoaxial joint. The guide wire should then pass 1 mm below the device tip. The system consists of flexible guide wires, a drill, a tap, and a screwdriver, and the screw is inserted easily via a posterior approach in which the patient's back is not obstructive. Ten patients with atlantoaxial subluxation or osteoarthritis underwent surgery in which the device was used. In all cases, the screws were inserted safely without causing VA injury, although preoperative computerized tomography (CT) reconstructions revealed a high-risk high-riding unilateral VA in three patients. Postoperative CT reconstructions demonstrated that all screws but one were inserted as planned, and successfully cleared the vertebral groove. In conclusion, this newly designed device is practical and useful for the accurate insertion of screws, thus avoiding VA injury during atlantoaxial transarticular screw fixation. PMID:12120635

Neo, Masasi; Matsushita, Mutsumi; Yasuda, Tadashi; Sakamoto, Takeshi; Nakamura, Takashi

2002-07-01

143

Passive Posterior Tibial Subluxation on Routine Knee MRI as a Secondary Sign of PCL Tear  

PubMed Central

The posterior drawer test is an accurate clinical test to diagnose posterior cruciate ligament (PCL), indicating laxity of the PCL that allows posterior tibial translation. This study aimed to determine whether posterior tibial translation relative to the femur on routine MRI could serve as an additional sign of PCL tear. Routine knee MRI in eleven patients (7 males, 4 females) with arthroscopically confirmed isolated PCL tears were reviewed independently by two musculoskeletal radiologists. Measurements of tibial translation were made in the medial and lateral compartments of patients and controls (10 males, 12 females) without clinical or MRI evidence of ligament injury. Significant medial compartment posterior tibial translation was present in patients with PCL tear compared to controls (+2.93?mm versus +0.03?mm, P = 0.002) with excellent interobserver agreement (intraclass correlation coefficient (ICC) = 0.94). No significant difference in lateral compartment tibial translation was observed (+0.17?mm versus ?0.57?mm, P = 0.366) despite excellent interobserver agreement (ICC = 0.96). Posterior tibial translation in the midmedial compartment may be a secondary sign of isolated PCL tear on routine knee MRI with passive extension without manipulation or weight bearing. Additional work in a larger cohort may better address the accuracy of this finding. PMID:25587446

Degnan, Andrew J.; Maldjian, Catherine; Adam, Richard J.; Harner, Christopher D.

2014-01-01

144

Echocardiographic examination of the posterior atrioventricular groove.  

PubMed

Abnormalities of the posterior atrioventricular (AV) groove may be mischaracterized or overlooked in the course of routine echocardiographic imaging. Vascular abnormalities in this location include plethora of the coronary sinus and ectasia of the circumflex coronary artery. Excess accumulation of calcium (mitral annular calcification) and of fat (lipomatosis of the posterior AV groove) may also occur in this region. Masses (tumors or thrombus) arising from the floor of the left atrium or extrinsic to it (hiatal hernia, lymph nodes) may occupy the posterior AV groove. Abnormalities of the left ventricle, including aneurysms and pseudoaneurysms may present as masses in the posterior AV groove. This article discusses the echocardiographic features, differential diagnosis, and clinical significance of these abnormalities. PMID:24495083

Silbiger, Jeffrey J

2014-02-01

145

Subjectivistic Interpretations of Probability  

E-print Network

Subjectivistic Interpretations of Probability The most recent and one of the most- abilities concern actual degrees of belief. Although this interpretation of probability was presented de Finetti, the subjectivistic interpretation o/ probability had no great effects on English

Fitelson, Branden

146

Probability 1/e  

ERIC Educational Resources Information Center

Quite a number of interesting problems in probability feature an event with probability equal to 1/e. This article discusses three such problems and attempts to explain why this probability occurs with such frequency.

Koo, Reginald; Jones, Martin L.

2011-01-01

147

[Pathogenesis of posterior capsule opacification in pseudophakia].  

PubMed

The lens epithelial cells of A and E type are involved in pathogenesis of posterior capsule opacification (PCO). They undergo metaplasia into microfibroblasts, then migrate towards posterior capsule where they proliferate and form opacification. These processes are stimulated by cytokines and interleukines. The extracellular matrix which constitutes a scaffold for migration and attachment of epithelial cells plays an important role in PCO formation. Integrines intercede in this process. PMID:20169899

?ukaszewska-Smyk, Agnieszka; Ka?uzny, Józef

2009-01-01

148

Cognitive rehabilitation in posterior cortical atrophy  

Microsoft Academic Search

Posterior cortical atrophy (PCA) is a rare early-onset dementing syndrome presenting with visuo-perceptual deficits. Clinicopathologically, it is most commonly considered a form of Alzheimer's disease. We present the case of a 64-year-old male patient with posterior cortical atrophy who took part in a cognitive rehabilitation programme that included psychoeducation, compensatory strategies, and cognitive exercises. After the cognitive rehabilitation programme, subtle

María Roca; Ezequiel Gleichgerrcht; Teresa Torralva; Facundo Manes

2010-01-01

149

Posterior atlantoaxial dislocation without associated fracture.  

PubMed

We report on a 38-year-old man with post-traumatic posterior displacement of the atlas with respect to the axis without any associated fracture or neurological deficit caused by the displacement. Radiographs, computed tomography (CT) and magnetic resonance imaging (MRI) revealed posterior displacement of the atlas with the odontoid peg lying anterior and to the right of the anterior arch of the atlas. PMID:12195506

Sud, S; Chaturvedi, S; Buxi, T B S; Singh, S

2002-09-01

150

Posterior odds ratios for selected regression hypotheses  

Microsoft Academic Search

Summary  Bayesian posterior odds ratios for frequently encountered hypotheses about parameters of the normal linear multiple regression\\u000a model are derived and discussed. For the particular prior distributions utilized, it is found that the posterior odds ratios\\u000a can be well approximated by functions that are monotonic in usual sampling theoryF statistics. Some implications of this finding and the relation of our work

A. Zellner; A. Siow

1980-01-01

151

High-resolution OCT: an innovative tool for posterior segment imaging.  

PubMed

Optimal management of posterior segment disorders requires a high-resolution and preferably noninvasive imaging tool for better definition of diseases. High-resolution optical coherence tomography can provide noninvasive, high-definition imaging of the posterior segment, allowing earlier diagnosis, better follow-up of chronic cases, and more accurate and timely monitoring of the effect of therapeutic agents. Recent findings suggest an individualized approach to vitreoretinal and choroidal diseases is possible based not only on traditional ophthalmic investigations, but also on high-resolution optical coherence tomography. This innovative tool has the combined advantages of high speed, high resolution, and safe use. PMID:23357319

Abdallah, Walid F; Olmos de Koo, Lisa C; Abdulkader, Mohamed M; Barnett, Cullen; Chader, Gerald J; Humayun, Mark S

2012-01-01

152

Accurate Unlexicalized Parsing  

Microsoft Academic Search

We demonstrate that an unlexicalized PCFG can parse much more accurately than previously shown, by making use of simple, linguistically motivated state splits, which break down false independence assumptions latent in a vanilla treebank grammar. Indeed, its performance of 86.36% (LP\\/LR F PCFG models, and surprisingly close to the current state-of-the-art. This result has potential uses beyond establishing a strong

Dan Klein; Christopher D. Manning

2003-01-01

153

Probability Calculus Bayesian Networks  

E-print Network

Probability Calculus Bayesian Networks Logic and Bayesian Networks Part 1: Probability Calculus and Bayesian Networks Jinbo Huang Jinbo Huang Probability Calculus and Bayesian Networks 1/ 31 #12;Probability Calculus Bayesian Networks What This Course Is About Probabilistic reasoning with Bayesian networks

Huang, Jinbo

154

Probability Calculus Bayesian Networks  

E-print Network

Probability Calculus Bayesian Networks Logic and Bayesian Networks Part 1: Probability Calculus and Bayesian Networks Jinbo Huang NICTA and ANU Jinbo Huang Probability Calculus and Bayesian Networks 1/ 31 #12;Probability Calculus Bayesian Networks What This Course Is About Probabilistic reasoning

Huang, Jinbo

155

The Gaussian sum convolution probability hypothesis density filter  

Microsoft Academic Search

A new multi-target tracking algorithm, termed as the Gaussian sum convolution probability hypothesis density (GSCPHD) filter, is proposed. The filter is calculated by a bank of convolution filters with Gaussian approximations to the predicted and posterior densities. It is shown that the ability to deal with complex observation model, non or small observation noise of the GSCPHD over the Gaussian

Jian Jun Yin; Jian Qiu Zhang; Ze Sen Zhuang

2008-01-01

156

Frequency versus probability formats in statistical word problems  

Microsoft Academic Search

Three experiments examined people's ability to incorporate base rate information when judging posterior probabilities. Specifically, we tested the (Cosmides, L., & Tooby, J. (1996). Are humans good intuitive statisticians after all? Rethinking some conclusions from the literature on judgement under uncertainty. Cognition, 58, 1–73) conclusion that people's reasoning appears to follow Bayesian principles when they are presented with information in

Jonathan St. B. t. Evans; Simon J. Handley; Nick Perham; David E. Over; Valerie A. Thompson

2000-01-01

157

Anterior versus posterior plating in cervical corpectomy.  

PubMed

This is a prospective study comparing anterior and posterior plating in cervical corpectomy. Each group comprised 30 patients who were candidates for corpectomy. In the first group, anterior plating was done using Orosco-type titanium plates. In the second group, lateral mass plating was done. In all cases, titanium cages were used to replace the removed vertebral body or bodies. The mean follow-up was 12.68 months (SD 3.85 months). Pseudarthrosis was not encountered in either group. Posterior plating was better than anterior plating in terms of the stability of the construct and problems related to the hardware. Screw breakage was encountered in seven patients with anterior plating (23.33%). This complication was not seen in the group with posterior plating. The difference between the groups was statistically significant (chi-square = 7.92, p = 0.004). Screw loosening was encountered in 2 patients in the group with anterior plating and in only 1 patient in the group with posterior plating. The difference between the incidence of screw loosening in both groups was not statistically significant (chi-square = 0.35, p = 0.5). Sinking-in of the cage was encountered in 7 cases with anterior plating and in only 3 cases with posterior plating. However, the difference between the groups was not statistically significant (chi-square = 1.92, p = 0.16). PMID:11110134

ElSaghir, H; Böhm, H

2000-01-01

158

[Clinical report of posterior leukoencephalopathy syndrome].  

PubMed

The article describes the case history of posterior leukoencephalopathy syndrome - a brain disorder that predominantly affects the cerebral white matter. Edematous lesions involve the posterior parietal and occipital lobes, and may spread to basal ganglia, brain stem and cerebellum. This rapidly evolving neurological condition is clinically characterized by headache, nausea and vomiting, seizures, visual disturbances and altered sensorial functions, and occasionally focal neurological deficit. Posterior leukoencephalopathy syndrome is often associated with an abrupt increase in blood pressure and is usually seen in patients with eclampsia, renal disease and hypertensive encephalopathy. It is also seen in the patients treated with cytotoxic and immunosuppressive drugs such as cyclosporine A, tacrolimus /FK-506, cisplatin, cytarabine, IVIg, erytrophoietin, and interferon alpha. The study demonstrated that lesions of posterior leukoencephalopathy syndrome are best visualized with magnetic resonance [MR] imaging. T2 weighted MR Images, at the height of symptoms, characteristically show diffuse hyper intensity selectively involving the parieto - occipital white matter. Occasionally the lesions also involve the grey matter. Computed tomography can also be used satisfactorily to detect hypodense lesions of posterior leukoencephalopathy. Early recognition of this condition is of paramount importance because prompt control of blood pressure, withdrawal of immunosuppressive agents will cause reversal of the syndrome. Delay in the diagnosis and treatment can result in permanent damage to affected brain tissues. The clinical data and radiological findings depicted in the study add to the investigation of the disorder. PMID:18323587

Akhvlediani, R; Mogylevsky, A; Contant, S

2008-01-01

159

The Dirichlet process, related priors and posterior asymptotics  

E-print Network

2 The Dirichlet process, related priors and posterior asymptotics Subhashis Ghosal Here we review properties of posterior distributions. Starting with the definition of posterior consistency and examples posterior convergence rates and briefly outline how such rates can be computed in nonparametric examples. We

Ghoshal, Subhashis

160

The Local Sensitivity of Posterior Expectations Paul Gustafson 1  

E-print Network

The Local Sensitivity of Posterior Expectations Paul Gustafson 1 Carnegie Mellon University We investigate the degree to which posterior expectations are sensitive to prior distributions, using a local of posteriors (or perhaps just a particular posterior quantity), that arises from a specified class of priors

161

Improving power posterior estimation of statistical evidence , Merrilee Hurn  

E-print Network

Improving power posterior estimation of statistical evidence Nial Friel , Merrilee Hurn and Jason. This paper focuses on refining the power posterior approach to improve estimation of the evidence. The power posterior method involves transitioning from the prior to the posterior by powering the likelihood

Hurn, Merrilee

162

Clinical evaluation of posterior canal benign paroxysmal positional vertigo  

PubMed Central

Background: Benign paroxysmal positional vertigo (BPPV) is a mechanical peripheral vestibular disorder which may involve any of the three semicircular canals but principally the posterior. In as much as the literature has described theories to explain the mechanism of BPPV and also contains scholarly works that elucidate BPPV; its management remains an enigma to most clinicians. To this end, this work was aimed at outlining an evidence-based best practice for most common form of BPPV. Materials and Methods: A systematic review of the literature was conducted between 1948 and June 2011 in PubMed, Embase, Ovid, and Cochrane database through the online Library of the University of Cape Town. Seventy-nine worthy articles that addressed the study were selected on consensus of the two authors. Conclusion: There is consensus for the use of canalith repositioning procedures as the best form of treatment for posterior canal canalolithiasis. However, successful treatment is dependent on accurate identification of the implicated canal and the form of lithiasis. Furthermore, clinicians should note that there is no place for pharmacological treatment of BPPV; unless it is to facilitate repositioning. PMID:23271854

Ibekwe, Titus S.; Rogers, C.

2012-01-01

163

Probability and paternity testing.  

PubMed Central

A probability can be viewed as an estimate of a variable that is sometimes 1 and sometimes 0. To have validity, the probability must equal the expected value of that variable. To have utility, the average squared deviation of the probability from the value of that variable should be small. It is shown that probabilities of paternity calculated by the use of Bayes' theorem under appropriate assumptions are valid, but they can vary in utility. In particular, a recently proposed probability of paternity has less utility than the usual one based on the paternity index. Using an arbitrary prior probability in the calculation cannot lead to a valid probability unless, by chance, the chosen prior probability happens to be appropriate. Appropriate assumptions regarding both the prior probability and gene or genotypic frequencies can be estimated from prior experience. Images Fig. 3 PMID:3752078

Elston, R C

1986-01-01

164

Giant epidermoid cyst of the posterior neck.  

PubMed

A 49-year-old man was presented for evaluation of a painless mass on his right posterior neck. The mass had gradually enlarged for a 25-year period without inflammation or rupture. On physical examination, a round, nontender, soft-tissue mass, 8 cm in diameter, was noted on the right posterior neck. The neck is a common site of epidermoid cysts, but a mass more than 5 cm in diameter is rare. A contrast-enhanced neck computed tomographic (CT) scan revealed a 7.6 × 6.5 × 5.7 cm unilocular hypodense mass adjacent to the posterior neck muscles.The mass was completely excised under general anesthesia. A histopathologic examination of the excised specimen resulted in a diagnosis of an epidermoid cyst. The patient was discharged from the hospital on the third postoperative day. There were no recurrences in a 2-year follow-up period. PMID:21586972

Kim, Cheesun; Park, Myong Chul; Seo, Seung Jo; Yoo, Young Moon; Jang, Yu Jin; Lee, Il Jae

2011-05-01

165

Late presentation of posterior urethral valves.  

PubMed

Presence of posterior urethral valves (PUV) is the most common cause of urinary tract obstruction in the male neonate. Late presentation occurs in 10% of cases. We present a case of PUVs in an adult male who presented with history of obstructive lower urinary tract symptoms and hematuria. On evaluation, he was found to have raised serum creatinine level. A voiding cystourethrogram (VCUG) could not be completely performed because of narrowing in the posterior urethra. A rigid urethrocystoscopy was performed at which he was found to have type-I posterior urethral valve which were fulgurated. A repeat uroflowmetry revealed maximum flow rate of 12 ml/second. This case highlights that PUVs is not solely a disease of infancy but may also present late. VCUG is the radiological investigation of choice but the diagnosis may be missed. A urethrocystoscopy is advised if there is a high index of suspicion. PMID:24906275

Jalbani, Imran Khan; Biyabani, Syed Raziuddin

2014-05-01

166

Accurate quantum chemical calculations  

NASA Technical Reports Server (NTRS)

An important goal of quantum chemical calculations is to provide an understanding of chemical bonding and molecular electronic structure. A second goal, the prediction of energy differences to chemical accuracy, has been much harder to attain. First, the computational resources required to achieve such accuracy are very large, and second, it is not straightforward to demonstrate that an apparently accurate result, in terms of agreement with experiment, does not result from a cancellation of errors. Recent advances in electronic structure methodology, coupled with the power of vector supercomputers, have made it possible to solve a number of electronic structure problems exactly using the full configuration interaction (FCI) method within a subspace of the complete Hilbert space. These exact results can be used to benchmark approximate techniques that are applicable to a wider range of chemical and physical problems. The methodology of many-electron quantum chemistry is reviewed. Methods are considered in detail for performing FCI calculations. The application of FCI methods to several three-electron problems in molecular physics are discussed. A number of benchmark applications of FCI wave functions are described. Atomic basis sets and the development of improved methods for handling very large basis sets are discussed: these are then applied to a number of chemical and spectroscopic problems; to transition metals; and to problems involving potential energy surfaces. Although the experiences described give considerable grounds for optimism about the general ability to perform accurate calculations, there are several problems that have proved less tractable, at least with current computer resources, and these and possible solutions are discussed.

Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.

1989-01-01

167

Endoscopic treatment of posteriorly localized talar cysts  

Microsoft Academic Search

Purpose  This study presents the short-term follow-up results from our case series of patients with posteriorly localized intraosseous\\u000a talar cysts. Patients were treated via hindfoot endoscopy in the prone position.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  We evaluated six ankles of five patients treated with hindfoot endoscopy for intraosseous cysts localized to the posterior\\u000a portion of talus. Three patients were men and two were women. The median

Tahir Ogut; Ali Seker; Fulya Ustunkan

2011-01-01

168

Systematic Review of Cadaveric Studies on Anatomic Posterior Cruciate Ligament Reconstruction: The Landmarks in Anatomic Posterior Cruciate Ligament Reconstruction  

PubMed Central

Recently, several new techniques for anatomic posterior cruciate ligament reconstruction (PCLR) have emerged and are believed to restore the normal anatomy of the posterior cruciate ligament more accurately. Despite the latest trend, the optimal methods for anatomic PCLR remain controversial. The purpose of this research is to review surgical techniques for PCLR in cadaver studies and suggest consistent and reproducible technical criteria. For the review of the literature, MEDLINE and EMBASE were screened for articles on anatomic PCLR. Only basic science studies on PCLR performed on human cadavers and written in English were included. Seventeen studies were included in this systematic review. Only the tunnel positions, graft types, and surgical techniques were reported in the majority of the studies. There were many variations of the reported tunnel positions, graft types, and surgical techniques among the studies. In most studies, surgical techniques for consistent and reproducible anatomic PCLR were not explained clearly. Therefore, high level medical research should be encouraged in order to establish standard surgical techniques for anatomic PCLR. PMID:25505700

Lee, Dong Yeong; Kim, Dong Hee; Park, Jin Sung; Nam, Dae Cheol; Cho, Seong Hee; Jeong, Jin Hoon

2014-01-01

169

Popliteal pseudoaneurysm after arthroscopic posterior cruciate ligament reconstruction.  

PubMed

This report presents the case of a 30-year-old motocross (BMX) cyclist with a third-degree posterior cruciate ligament rupture. The technique used for reconstruction was the transtibial single-bundle autologous hamstring technique. Unfortunately, the procedure was complicated by a popliteal pseudoaneurysm, which was located in line with the tibial canal. The pseudoaneurysm was treated with an end-to-end anastomosis and the patient recovered without further complaints. In this case, the popliteal artery was damaged most probably by the edge of the reamer or the guide wire during removal. Vascular complications can be limb- and life-threatening. This case report aims to increase the awareness of this serious complication with a review of the literature. PMID:25229050

van Dorp, Karin B; Breugem, Stefan J M; Driessen, Marcel J M

2014-09-01

170

Popliteal Pseudoaneurysm after Arthroscopic Posterior Cruciate Ligament Reconstruction  

PubMed Central

This report presents the case of a 30-year-old motocross (BMX) cyclist with a third-degree posterior cruciate ligament rupture. The technique used for reconstruction was the transtibial single-bundle autologous hamstring technique. Unfortunately, the procedure was complicated by a popliteal pseudoaneurysm, which was located in line with the tibial canal. The pseudoaneurysm was treated with an end-to-end anastomosis and the patient recovered without further complaints. In this case, the popliteal artery was damaged most probably by the edge of the reamer or the guide wire during removal. Vascular complications can be limb- and life-threatening. This case report aims to increase the awareness of this serious complication with a review of the literature. PMID:25229050

Breugem, Stefan J.M.; Driessen, Marcel J.M.

2014-01-01

171

Arthroscopic Posterior Bone Block Procedure: A New Technique Using Suture Anchor Fixation  

PubMed Central

We present a novel all-arthroscopic technique of posterior shoulder stabilization that uses suture anchors for both bone block fixation and capsulolabral repair. The bone graft, introduced inside the glenohumeral joint through a cannula, is fixed with 2 suture anchors. The associated posteroinferior capsulolabral repair places the bone block in an extra-articular position. In this article we present the detailed arthroscopic technique performed in a consecutive series of 15 patients and report the early results. We also report the positioning, healing, and remodeling of the bone block using postoperative 3-dimensional computed tomography. The benefits of this new technique are as follows: (1) it is all arthroscopic, preserving the posterior deltoid and posterior rotator cuff muscles; (2) it is accurate, resulting in appropriate bone block positioning; (3) it is efficient, allowing for consistent bone graft healing; (4) it is anatomic, both restoring the glenoid bone stock and repairing the injured posterior labrum; and (5) it is safe, limiting hardware-related complications and eliminating the risk of injury to vital structures associated with drilling or screw insertion from posterior to anterior. We believe that this technique is advantageous because it does not use screws for fixation and may be safer for the patient. PMID:24892011

Boileau, Pascal; Hardy, Marie-Béatrice; McClelland, Walter B.; Thélu, Charles-Edouard; Schwartz, Daniel G.

2013-01-01

172

BIODEGRADATION PROBABILITY PROGRAM (BIODEG)  

EPA Science Inventory

The Biodegradation Probability Program (BIODEG) calculates the probability that a chemical under aerobic conditions with mixed cultures of microorganisms will biodegrade rapidly or slowly. It uses fragment constants developed using multiple linear and non-linear regressions and d...

173

Introduction to Probability  

NSDL National Science Digital Library

This resource is designed to introduce students to the concept of probability: the probability of a rare event is represented by a positive number close to zero, the probability of a nearly certain event occurring is represented by a positive number slightly less than one. Students will indicate the approximate probability of events on a number line and determine which events are more likely than others.

Steven Blumsack

2012-09-14

174

Probability - Lesson Plan  

NSDL National Science Digital Library

This probability lesson plan requires students to use probability vocabulary to describe events as likely, unlikely, equally likely, impossible, or certain. Students then use this information to help them conduct experiments and interpret probability as a fraction or on a number line as a value between 0 and 1. This lesson plan includes links to an online probability game (cataloged separately), an online quiz, and two documents (rtf) for student work.

2012-10-05

175

Data Analysis & Probability  

NSDL National Science Digital Library

Probability is fun! First, guess the magicians number in Magician Probability! Next, answer the questions on 'which is more likely" in the game Probability comparisons. Then, Help sort our Earth in the sorting game. All you have to do is pick up the trash and sort it into the correct pile. Finally, try pumpkin sorting. Just drag the pumpkins into a sorting ...

Ms. Taylor

2009-05-03

176

Dependent Probability Spaces  

ERIC Educational Resources Information Center

The mathematical model used to describe independence between two events in probability has a non-intuitive consequence called dependent spaces. The paper begins with a very brief history of the development of probability, then defines dependent spaces, and reviews what is known about finite spaces with uniform probability. The study of finite…

Edwards, William F.; Shiflett, Ray C.; Shultz, Harris

2008-01-01

177

Searching with probabilities  

SciTech Connect

This book examines how probability distributions can be used as a knowledge representation technique. It presents a mechanism that can be used to guide a selective search algorithm to solve a variety of tactical chess problems. Topics covered include probabilities and searching the B algorithm and chess probabilities - in practice, examples, results, and future work.

Palay, A.J.

1985-01-01

178

Fundamentals of probability  

NSDL National Science Digital Library

This is a free digital textbook on probability theory. It is ideal for a second-year undergraduate course in probability theory. It aims to fill the gap between elementary treatments of probability theory and more advanced treatments based on measure theory.

Dr. Marco Taboga

2010-08-23

179

INTENTIONAL MAPS IN POSTERIOR PARIETAL CORTEX  

Microsoft Academic Search

? Abstract The posterior parietal cortex (PPC), historically believed to be a sensory structure, is now viewed as an area important for sensory-motor integration. Among its functions is the forming of intentions, that is, high-level cognitive plans for movement. There is a map of intentions within the PPC, with different subregions dedicated to the planning of eye movements, reaching movements,

Richard A. Andersen; Christopher A. Buneo

2002-01-01

180

Posterior cruciate ligament tibial inlay reconstruction  

Microsoft Academic Search

A patellar bone-tendon-bone tibial inlay reconstruction of the posterior cruciate ligament using a popliteal arthrotomy was designed to minimize graft-tunnel wall abrasion. Arthroscopic techniques are used for femoral graft fixation. In a small series, the procedure decreased the quadriceps active drawer in 70° of flexion by an average of 4 mm and improved patellofemoral symptoms.

Eugene E. Berg

1995-01-01

181

Markov Chains for Exploring Posterior Distributions  

Microsoft Academic Search

Several Markov chain methods are available for sampling from a posterior distribution. Two important examples are the Gibbs sampler and the Metropolis algorithm. In addition, several strategies are available for constructing hybrid algorithms. This paper outlines some of the basic methods and strategies and discusses some related theoretical and practical issues. On the theoretical side, results from the theory of

Luke Tierney

1994-01-01

182

Abnormal visual phenomena in posterior cortical atrophy  

Microsoft Academic Search

Individuals with posterior cortical atrophy (PCA) report a host of unusual and poorly explained visual disturbances. This preliminary report describes a single patient (CRO), and documents and investigates abnormally prolonged colour afterimages (concurrent and prolonged perception of colours complimentary to the colour of an observed stimulus), perceived motion of static stimuli, and better reading of small than large letters. We

Sebastian J. Crutch; Manja Lehmann; Nikos Gorgoraptis; Diego Kaski; Natalie Ryan; Masud Husain; Elizabeth K. Warrington

2011-01-01

183

Benson's syndrome or Posterior Cortical Atrophy  

Microsoft Academic Search

Key-words Disease name and synonyms Definition \\/ diagnostic criteria Epidemiology Genetic Etiology Abstract Benson's syndrome or Posterior Cortical Atrophy (PCA) is a rare degenerative disorder clinically distinct from Alzheimer's disease (AD). Its frequency is unknown. PCA refers to a clinical syndrome in which higher order visual processing is disrupted owing to a neurodegenerative disorder. The patients present with progressive and

Alexis Brice

2004-01-01

184

Visual neglect in posterior cortical atrophy  

Microsoft Academic Search

BACKGROUND: In posterior cortical atrophy (PCA), there is a progressive impairment of high-level visual functions and parietal damage, which might predict the occurrence of visual neglect. However, neglect may pass undetected if not assessed with specific tests, and might therefore be underestimated in PCA. In this prospective study, we aimed at establishing the side, the frequency and the severity of

Katia Andrade; Dalila Samri; Marie Sarazin; Leonardo C de Souza; Laurent Cohen; Michel Thiebaut de Schotten; Bruno Dubois; Paolo Bartolomeo

2010-01-01

185

Imaging correlates of posterior cortical atrophy  

Microsoft Academic Search

The aim of this study was to compare patterns of cerebral atrophy on MRI, and neurochemistry on magnetic resonance spectroscopy (MRS), in patients with posterior cortical atrophy (PCA) and typical Alzheimer's disease (AD). Voxel-based morphometry was used to assess grey matter atrophy in 38 patients with PCA, 38 patients with typical AD, and 38 controls. Clinical data was assessed in

Jennifer L. Whitwell; Clifford R. Jack Jr.; Kejal Kantarci; Stephen D. Weigand; Bradley F. Boeve; David S. Knopman; Daniel A. Drubach; David F. Tang-Wai; Ronald C. Petersen; Keith A. Josephs

2007-01-01

186

“Apperceptive” Alexia in Posterior Cortical Atrophy  

Microsoft Academic Search

The most common presenting complaint in posterior cortical atrophy (PCA) is reading difficulty. Although often described as an alexia without agraphia, alexia in PCA may have multiple causes, including a primary visuoperceptual etiology, attentional alexia, and central reading difficulty. This study evaluated 14 patients with early PCA and disturbances in reading ability in comparison to 14 normal controls. All 14

Mario F. Mendez; Jill S. Shapira; David G. Clark

2007-01-01

187

Progressive visual agnosia with posterior cortical atrophy  

Microsoft Academic Search

A patient of posterior cortical atrophy, characterized by early signs of progressive visual agnosia documented by repeated neuropsychological tests, is reported. SPECT and MRI findings showed left unilateral parieto-occipital involvement in the earlier stage. A PET study executed eight months later showed bilateral parieto-occipital hypometabolism, but predominantly in the left hemisphere. This suggests that the degeneration may have developed asymmetrically,

Masafumi Mizuno; Giuseppe Sartori; Davide Liccione; Lorella Battelli; Rosario Campo

1996-01-01

188

Hearing results after posterior fossa vestibular neurectomy  

Microsoft Academic Search

The effect of posterior fossa vestibular neurectomy on postoperative hearing levels of 172 patients was studied at 1 week, 1 month, 1 year, and 18 to 24 months. According to the 1985 American Academy of Otolaryngology - Head and Neck Surgery guidelines for reporting treatment outcome, 66% of patients had improved or unchanged hearing at 18 to 24 months. One-week

SETH I. ROSENBERG; HERBERT SILVERSTEIN; MICHAEL E. HOFFER; ERICA THALER

1996-01-01

189

BAER suppression during posterior fossa dural opening  

PubMed Central

Background: Intraoperative monitoring with brainstem auditory evoked responses (BAER) provides an early warning signal of potential neurological injury and may avert tissue damage to the auditory pathway or brainstem. Unexplained loss of the BAER signal in the operating room may present a dilemma to the neurosurgeon. Methods: This paper documents two patients who displayed a unique mechanism of suppression of the BAER apparent within minutes following dural opening for resection of a posterior fossa meningioma. Results: In two patients with anterior cerebellopontine angle and clival meningiomas, there was a significant deterioration of the BAER soon after durotomy but prior to cerebellar retraction and tumor removal. Intracranial structures in the posterior fossa lying between the tumor and dural opening were shifted posteriorly after durotomy. Conclusion: We hypothesized that the cochlear nerve and vessels entering the acoustic meatus were compressed or stretched when subjected to tissue shift. This movement caused cochlear nerve dysfunction that resulted in BAER suppression. BAER was partially restored after the tumor was decompressed, dura repaired, and bone replaced. BAER was not suppressed following durotomy for removal of a meningioma lying posterior to the cochlear complex. Insight into the mechanisms of durotomy-induced BAER inhibition would allay the neurosurgeon's anxiety during the operation.

Shields, Christopher B.; Shields, Lisa B. E.; Jiang, Yi Dan; Yao, Tom; Zhang, Yi Ping; Sun, David A.

2015-01-01

190

Myopericytoma of the posterior cranial fossa.  

PubMed

Myopericytoma is a soft tissue tumour believed to be derived from perivascular myoid cells. They are typically found in subcutaneous tissues in the extremities. Intracranial myopericytomas are exceptionally rare. Here we report a man with an asymptomatic posterior fossa myopericytoma with evidence of dural infiltration. PMID:25177778

Zhang, Catherine H; Hasegawa, Harutomo; Johns, Paul; Martin, Andrew J

2014-09-01

191

Correction of Posterior Crossbites: Diagnosis and Treatment  

Microsoft Academic Search

The correction of posterior crossbites is more complex than it appears. To develop an appropriate treatment plan, it is first necessary to determine if: (1) there is a functional jaw shift on closing; (2) the crossbite is unilateral or bilateral; (3) it is dental, skeletal, or a combination of both; and (4) it is related only to the maxilla or

Robert E. Binder

2004-01-01

192

Subspecialization in the human posterior medial cortex.  

PubMed

The posterior medial cortex (PMC) is particularly poorly understood. Its neural activity changes have been related to highly disparate mental processes. We therefore investigated PMC properties with a data-driven exploratory approach. First, we subdivided the PMC by whole-brain coactivation profiles. Second, functional connectivity of the ensuing PMC regions was compared by task-constrained meta-analytic coactivation mapping (MACM) and task-unconstrained resting-state correlations (RSFC). Third, PMC regions were functionally described by forward/reverse functional inference. A precuneal cluster was mostly connected to the intraparietal sulcus, frontal eye fields, and right temporo-parietal junction; associated with attention and motor tasks. A ventral posterior cingulate cortex (PCC) cluster was mostly connected to the ventromedial prefrontal cortex and middle left inferior parietal cortex (IPC); associated with facial appraisal and language tasks. A dorsal PCC cluster was mostly connected to the dorsomedial prefrontal cortex, anterior/posterior IPC, posterior midcingulate cortex, and left dorsolateral prefrontal cortex; associated with delay discounting. A cluster in the retrosplenial cortex was mostly connected to the anterior thalamus and hippocampus. Furthermore, all PMC clusters were congruently coupled with the default mode network according to task-unconstrained but not task-constrained connectivity. We thus identified distinct regions in the PMC and characterized their neural networks and functional implications. PMID:25462801

Bzdok, Danilo; Heeger, Adrian; Langner, Robert; Laird, Angela R; Fox, Peter T; Palomero-Gallagher, Nicola; Vogt, Brent A; Zilles, Karl; Eickhoff, Simon B

2015-02-01

193

Posterior vertebral injury; is this a burst fracture or a flexion-distraction injury?  

PubMed

In thoracolumbar spinal fractures with posterior column injury for applying proper management, it is important to distinguish a flexion-distraction injury (FDI) from a three column burst fracture (BF) as in clinical examination, both may have a similar significant tenderness on direct spinal palpation. Careful attention to the comprehensive clinical examination and detailed imaging features are essential in making an accurate diagnosis and thus appropriate treatment. PMID:25207330

Omidi-Kashani, Farzad

2014-06-01

194

Predicted probabilities' relationship to inclusion probabilities.  

PubMed

It has been shown that under a general multiplicative intercept model for risk, case-control (retrospective) data can be analyzed by maximum likelihood as if they had arisen prospectively, up to an unknown multiplicative constant, which depends on the relative sampling fraction. (1) With suitable auxiliary information, retrospective data can also be used to estimate response probabilities. (2) In other words, predictive probabilities obtained without adjustments from retrospective data will likely be different from those obtained from prospective data. We highlighted this using binary data from Medicare to determine the probability of readmission into the hospital within 30 days of discharge, which is particularly timely because Medicare has begun penalizing hospitals for certain readmissions. (3). PMID:25790398

Fang, Di; Chong, Jenny; Wilson, Jeffrey R

2015-05-01

195

Accurate Model Selection of Relaxed Molecular Clocks in Bayesian Phylogenetics  

PubMed Central

Recent implementations of path sampling (PS) and stepping-stone sampling (SS) have been shown to outperform the harmonic mean estimator (HME) and a posterior simulation-based analog of Akaike’s information criterion through Markov chain Monte Carlo (AICM), in Bayesian model selection of demographic and molecular clock models. Almost simultaneously, a Bayesian model averaging approach was developed that avoids conditioning on a single model but averages over a set of relaxed clock models. This approach returns estimates of the posterior probability of each clock model through which one can estimate the Bayes factor in favor of the maximum a posteriori (MAP) clock model; however, this Bayes factor estimate may suffer when the posterior probability of the MAP model approaches 1. Here, we compare these two recent developments with the HME, stabilized/smoothed HME (sHME), and AICM, using both synthetic and empirical data. Our comparison shows reassuringly that MAP identification and its Bayes factor provide similar performance to PS and SS and that these approaches considerably outperform HME, sHME, and AICM in selecting the correct underlying clock model. We also illustrate the importance of using proper priors on a large set of empirical data sets. PMID:23090976

Baele, Guy; Li, Wai Lok Sibon; Drummond, Alexei J.; Suchard, Marc A.; Lemey, Philippe

2013-01-01

196

Accurate model selection of relaxed molecular clocks in bayesian phylogenetics.  

PubMed

Recent implementations of path sampling (PS) and stepping-stone sampling (SS) have been shown to outperform the harmonic mean estimator (HME) and a posterior simulation-based analog of Akaike's information criterion through Markov chain Monte Carlo (AICM), in bayesian model selection of demographic and molecular clock models. Almost simultaneously, a bayesian model averaging approach was developed that avoids conditioning on a single model but averages over a set of relaxed clock models. This approach returns estimates of the posterior probability of each clock model through which one can estimate the Bayes factor in favor of the maximum a posteriori (MAP) clock model; however, this Bayes factor estimate may suffer when the posterior probability of the MAP model approaches 1. Here, we compare these two recent developments with the HME, stabilized/smoothed HME (sHME), and AICM, using both synthetic and empirical data. Our comparison shows reassuringly that MAP identification and its Bayes factor provide similar performance to PS and SS and that these approaches considerably outperform HME, sHME, and AICM in selecting the correct underlying clock model. We also illustrate the importance of using proper priors on a large set of empirical data sets. PMID:23090976

Baele, Guy; Li, Wai Lok Sibon; Drummond, Alexei J; Suchard, Marc A; Lemey, Philippe

2013-02-01

197

Accurate spectral color measurements  

NASA Astrophysics Data System (ADS)

Surface color measurement is of importance in a very wide range of industrial applications including paint, paper, printing, photography, textiles, plastics and so on. For a demanding color measurements spectral approach is often needed. One can measure a color spectrum with a spectrophotometer using calibrated standard samples as a reference. Because it is impossible to define absolute color values of a sample, we always work with approximations. The human eye can perceive color difference as small as 0.5 CIELAB units and thus distinguish millions of colors. This 0.5 unit difference should be a goal for the precise color measurements. This limit is not a problem if we only want to measure the color difference of two samples, but if we want to know in a same time exact color coordinate values accuracy problems arise. The values of two instruments can be astonishingly different. The accuracy of the instrument used in color measurement may depend on various errors such as photometric non-linearity, wavelength error, integrating sphere dark level error, integrating sphere error in both specular included and specular excluded modes. Thus the correction formulas should be used to get more accurate results. Another question is how many channels i.e. wavelengths we are using to measure a spectrum. It is obvious that the sampling interval should be short to get more precise results. Furthermore, the result we get is always compromise of measuring time, conditions and cost. Sometimes we have to use portable syste or the shape and the size of samples makes it impossible to use sensitive equipment. In this study a small set of calibrated color tiles measured with the Perkin Elmer Lamda 18 and the Minolta CM-2002 spectrophotometers are compared. In the paper we explain the typical error sources of spectral color measurements, and show which are the accuracy demands a good colorimeter should have.

Hiltunen, Jouni; Jaeaeskelaeinen, Timo; Parkkinen, Jussi P. S.

1999-08-01

198

Ophthalmic Impairment or Higher-Order Visual Deficit? Posterior Cortical Atrophy: A Case Report  

Microsoft Academic Search

A 64-year-old man (GK) was referred to our memory clinic because of progressive memory and concentration problems. His symptoms had started 3 years earlier with gradually increasing visual problems for which no ophthalmologic explanations could be found. Neuropsychological assessment with detailed examination of the visuoperception revealed striking impairments in the higher-order visual functions, leading to a probable diagnosis of posterior

Carla Ruis; Esther van den Berg; Martine J. E. van Zandvoort; Kim Boshuisen; Catharina J. M. Frijns

2012-01-01

199

Posterior Pole Sparing Laser Photocoagulation Combined with Intravitreal Bevacizumab Injection in Posterior Retinopathy of Prematurity  

PubMed Central

Purpose. To report the results of the posterior pole sparing laser photocoagulation combined with intravitreal bevacizumab injection (IVB) in retinopathy of prematurity (ROP). Methods. A retrospective chart review of premature babies with ROP, all of whom received laser photocoagulation with IVB. Eleven eyes of 6 infants with advanced zone I ROP underwent laser ablation sparing posterior pole with concurrent IVB. The results were compared with those of full-laser treatment combined with IVB to 8 eyes of 5 infants with advanced ROP without involvement of the posterior pole. Results. The posterior pole sparing laser with IVB was performed with zone I, stage 3+ ROP at the mean postmenstrual age of 36 weeks and 5 days. The plus sign decreased significantly at postoperative day 1, the neovascular proliferation regressed by postoperative week 1, and the normal vascularization started at postoperative day 32 on the average. Two months after treatment, vascularization of the spared avascular area was completed. There was no macular dragging, tractional retinal detachment, foveal destruction by laser scars, or any other adverse event. No significant anatomical differences were identified from those of full-laser ablation combined with IVB. Conclusions. Posterior pole sparing laser with IVB can give favorable results without destruction of posterior pole retina. PMID:25614828

Kim, Rebecca; Kim, Yu Cheol

2014-01-01

200

P-values, q-values and posterior probabilities for equivalence in genomics studies  

E-print Network

or treatment regimens provide comparable therapeutic effects within pre-defined clinical and statistical limits treatment, or is less costly to produce. In such trials, a fixed level of statistical significance are required as part of the statistical inferential framework. Illustration 2: Experimental study of regulatory

Solomon, Patty

201

A model for equine breed identification using microsatellites and posterior probability testing  

E-print Network

, migration, interbreeding and natural selection pressures. Although breeds can be characterized by their blood types, the very recent divergence (approximately 300 years) of Thoroughbred horses from their Arabian ancestors restricts variation at this level..., Valdes et al. 1993) and reptiles (Dutton 1995, Fitzsimmons et al. 1995; Forstner 1995) as well as insects (Estoup et al. 1995). For example, genetic variation at hypervariable loci has been used for the successful resolution of human evolutionary trees...

Chastain, Pepper Alise

1996-01-01

202

Computing posterior probabilities for score-based alignments using ppALIGN.  

PubMed

Score-based pairwise alignments are widely used in bioinformatics in particular with molecular database search tools, such as the BLAST family. Due to sophisticated heuristics, such algorithms are usually fast but the underlying scoring model unfortunately lacks a statistical description of the reliability of the reported alignments. In particular, close to gaps, in low-score or low-complexity regions, a huge number of alternative alignments arise which results in a decrease of the certainty of the alignment. ppALIGN is a software package that uses hidden Markov Model techniques to compute position-wise reliability of score-based pairwise alignments of DNA or protein sequences. The design of the model allows for a direct connection between the scoring function and the parameters of the probabilistic model. For this reason it is suitable to analyze the outcomes of popular score based aligners and search tools without having to choose a complicated set of parameters. By contrast, our program only requires the classical score parameters (the scoring function and gap costs). The package comes along with a library written in C++, a standalone program for user defined alignments (ppALIGN) and another program (ppBLAST) which can process a complete result set of BLAST. The main algorithms essentially exhibit a linear time complexity (in the alignment lengths), and they are hence suitable for on-line computations. We have also included alternative decoding algorithms to provide alternative alignments. ppALIGN is a fast program/library that helps detect and quantify questionable regions in pairwise alignments. Due to its structure, the input/output interface it can to be connected to other post-processing tools. Empirically, we illustrate its usefulness in terms of correctly predicted reliable regions for sequences generated using the ROSE model for sequence evolution, and identify sensor-specific regions in the denitrifying betaproteobacterium Aromatoleum aromaticum. PMID:22628350

Wolfsheimer, Stefan; Hartmann, Alexander; Rabus, Ralf; Nuel, Gregory

2012-01-01

203

Applied Probability Trust (6 June 2008) ASYMPTOTICS OF POSTERIORS FOR BINARY BRANCHING  

E-print Network

of polymerase chain reaction. Probabilistic models of polymerase chain reactions were proposed and studied and Sagitov (2002). In models of polymerase chain reactions and in similar contexts, the initial pop- ulation processes; Bayesian estimation; Polymerase chain reac- tions 2000 Mathematics Subject Classification

Paris-Sud XI, Université de

204

Applied Probability Trust (11 March 2008) ASYMPTOTICS OF POSTERIORS FOR BINARY BRANCHING  

E-print Network

of polymerase chain reaction. Probabilistic models of polymerase chain reactions were proposed and studied and Sagitov (2002). In models of polymerase chain reactions and in similar contexts, the initial pop- ulation processes; Bayesian estimation; Polymerase chain reac- tions 2000 Mathematics Subject Classification

Paris-Sud XI, Université de

205

Right Haar Measure for Convergence in Probability to Quasi Posterior Distributions  

Microsoft Academic Search

Many statistical problems contain an infinite parameter space or are analyzed as if they contained one. In a Bayesian analysis of such a problem, there is often, for one or more of several reasons, an attraction in employing an infinite measure on parameter space in the role of `prior distribution' of the parameter. The employment of such a quasi prior

M. Stone

1965-01-01

206

Anterior canal BPPV and apogeotropic posterior canal BPPV: two rare forms of vertical canalolithiasis.  

PubMed

Posterior canal benign paroxysmal positional vertigo (BPPV) is the most frequent form of BPPV. It is characterized by a paroxysmal positioning nystagmus evoked through Dix-Hallpike and Semont positioning tests. Anterior canal BPPV (AC) is more rare than posterior canal BPPV; it presents a prevalent down beating positioning nystagmus, with a torsional component clockwise for the left canal, counterclockwise for the right canal. Due to the possible lack of the torsional component, it is sometimes difficult to identify the affected ear. An apogeotropic variant of posterior BPPV (APC) has recently been described, characterised by a paroxysmal positional nystagmus in the opposite direction to the one evoked in posterior canal BPPV: the linear component is down-beating, the torsional component is clockwise for the right canal, counter-clockwise for the left canal, so that a contra-lateral anterior canal BPPV could be simulated. During a 16 month period, of 934 BPPV patients observed, the authors identified 23 (2.5%) cases of apogeotropic posterior canal BPPV and 11 (1.2%) cases of anterior canal BPPV, diagnosed using the specific oculomotor patterns described in the literature. Anterior canal BPPV was treated with the repositioning manoeuvre proposed by Yacovino, which does not require identification of the affected side, whereas apogeotropic posterior canal BPPV was treated with the Quick Liberatory Rotation manoeuvre for the typical posterior canal BPPV, since in the Dix-Hallpike position otoliths are in the same position if they come either from the ampullary arm or from the non-ampullary arm. The direct resolution of BPPV (one step therapy) was obtained in 12/34 patients, 8/23 patients with APC and 4/11 patients with AC; canalar conversion into typical posterior canal BPPV, later treated through Quick Liberatory Rotation (two-step therapy), was obtained in 19 patients,14/23 with APC and 5/11 with AC. Three patients were lost to follow-up. Considering the effects of therapeutic manoeuvres, the authors propose a grading system for diagnosis of AC and APC: "certain" when a canalar conversion in ipsilateral typical posterior canal BPPV is obtained; "probable" when APC or AC are directly resolved; "possible" when disease is not resolved and cerebral neuroimaging is negative for neurological diseases. Our results show that the oculomotor patterns proposed in the literature are effective in diagnosing APC and AC, and that APC is more frequent than AC. Both of these rare forms of vertical canal BPPV can be treated effectively with liberatory manoeuvres. PMID:24882928

Califano, L; Salafia, F; Mazzone, S; Melillo, M G; Califano, M

2014-06-01

207

Earthquake Probability Mapping  

NSDL National Science Digital Library

This mapping tool allows users to generate Earthquake Probability Maps (EPMs) for a region within 50 kilometers of a location specified by latitude and longitude or by ZIP code. The maps are color-coded; higher earthquake probabilities are indicated by orange and red colors, while lower probabilities are indicated by green or blue. Fault traces are marked in white; rivers are in blue. The maps are also produced in downloadable, printable format (PDF).

208

Pseudoexfoliation material on posterior chamber intraocular lenses  

PubMed Central

The presence of pseudoexfoliation material on the surface of an intraocular lens (IOL) is a rare finding. We report a series of seven cases with different patterns of pseudoexfoliation material deposition on the posterior chamber IOLs, recognized 2–20 years after cataract surgery. Six patients had an IOL implanted in the capsular bag and one in the ciliary sulcus. Two patients had undergone posterior capsulotomy. Although the pathophysiological mechanisms and clinical significance of this finding remain unknown, the careful follow-up of pseudophakic patients with known or suspected pseudoexfoliation syndrome is essential to monitor the development or progression of glaucoma, since deposition of pseudoexfoliation material continues even after cataract surgery. PMID:25143707

da Rocha-Bastos, Ricardo António; Silva, Sérgio Estrela; Prézia, Flávio; Falcão-Reis, Fernando; Melo, António B

2014-01-01

209

Posterior tibial nerve lesions in ankle arthroscopy.  

PubMed

Ankle arthroscopy provides a minimally invasive approach to the diagnosis and treatment of certain ankle disorders. Neurological complications resulting from ankle arthroscopy have been well documented in orthopaedic and podiatric literature. Owing to the superficial location of the ankle joint and the abundance of overlying periarticular neurovascular structures, complications reported in ankle arthroscopy are greater than those reported for other joints. In particular, all reported neurovascular injuries following ankle arthroscopy have been the direct result of distractor pin or portal placement. The standard posteromedial portal has recognized risks because of the proximity of the posterior neurovascular structures. There can be considerable variability in the course of these portals and their proximity to the neurovascular structures. We found one report of intra-articular damage to the posterior tibial nerve as a result of ankle arthroscopy in the English-language literature and we report this paper as a second case described in the literature. PMID:17618442

Cugat, Ramon; Ares, Oscar; Cuscó, Xavier; Garcia, Montserrat; Samitier, Gonzalo; Seijas, Roberto

2008-05-01

210

Posterior fossa lesions associated with neuropsychiatric symptomatology.  

PubMed

We reviewed 7 cases with posterior fossa structural abnormalities (3 tumors, 2 megacisterna magna and 2 Dandy-Walker syndrome) presenting with neuropsychiatric symptomatology. Derangement in the balance of dopamine, serotonin and noradrenergic networks has been implicated in the pathogenesis of schizophrenia, affective and even personality disorders. Disruption of the cerebellar output to mesial dopaminergic areas, locus coeruleus and raphe nuclei, or deafferentation of the thalamolimbic circuits by a cerebellar lesion may lead to behavioral changes. Seven patients (pts) (comprising 4 men and 3 women with mean age 22 years) were diagnosed as suffering from psychosis (2 pts), major depression (1 pt), personality disorders (2 pts) and somatoform disorders (2 pts) (DSM-IV criteria). Brain CT scan (7 pts) and MRI (4 pts) revealed tumors of the posterior fossa (2 pts), megacisterna magna (2 pts) and Dandy-Walker variant (2 pts). In one patient a IVth ventricle tumor was removed in childhood. PMID:9003973

Pollak, L; Klein, C; Rabey, J M; Schiffer, J

1996-11-01

211

Approaching system equilibrium with accurate or not accurate feedback information in a two-route system  

NASA Astrophysics Data System (ADS)

With the development of intelligent transport system, advanced information feedback strategies have been developed to reduce traffic congestion and enhance the capacity. However, previous strategies provide accurate information to travelers and our simulation results show that accurate information brings negative effects, especially in delay case. Because travelers prefer to the best condition route with accurate information, and delayed information cannot reflect current traffic condition but past. Then travelers make wrong routing decisions, causing the decrease of the capacity and the increase of oscillations and the system deviating from the equilibrium. To avoid the negative effect, bounded rationality is taken into account by introducing a boundedly rational threshold BR. When difference between two routes is less than the BR, routes have equal probability to be chosen. The bounded rationality is helpful to improve the efficiency in terms of capacity, oscillation and the gap deviating from the system equilibrium.

Zhao, Xiao-mei; Xie, Dong-fan; Li, Qi

2015-02-01

212

Statistics and Probability Tutorial  

NSDL National Science Digital Library

This tutorial, created by Harvey Berman of Stat Trek, provides a basic introduction to many topics in statistics and probability. Topics include: sets and subsets, statistical experiments, counting, basic probability rules, Bayes' theorem, probability distributions, discrete versus continuous, binomial, negative binomial, hypergeometric, multinomial, Poisson, normal, sampling theory, central tendency, variability, sampling distributions, t-distribution, Chi-square distribution, F-distribution, estimation problems, hypothesis testing, power, survey sampling, simple random samples, stratified samples, cluster samples, sample size. This is a general overview of statistics and probability. It is geared towards a high school advanced placement level.

Berman, Harvey

213

Statistics and Probability  

NASA Astrophysics Data System (ADS)

This ourse constitutes a brief introduction to probability applications in high energy physis. First the mathematical tools related to the diferent probability conepts are introduced. The probability distributions which are commonly used in high energy physics and their characteristics are then shown and commented. The central limit theorem and its consequences are analysed. Finally some numerical methods used to produce diferent kinds of probability distribution are presented. The full article (17 p.) corresponding to this lecture is written in french and is provided in the proceedings of the book SOS 2008.

Laktineh, Imad

2010-04-01

214

Posterior vaginal prolapse and bowel function  

Microsoft Academic Search

Objective: This study’s objectives were to describe symptoms related to bowel dysfunction in women with uterovaginal prolapse and to compare these symptoms according to extent of posterior vaginal prolapse. Study Design: One hundred forty-three women completed a questionnaire assessment of bowel function and underwent standardized physical examination according to the International Continence Society’s system for grading uterovaginal prolapse. Results: The

Anne M. Weber; Mark D. Walters; Lester A. Ballard; Delbert L. Booher; Marion R. Piedmonte

1998-01-01

215

Posterior cortical atrophy: A brief review  

Microsoft Academic Search

Posterior cortical atrophy is a striking clinical syndrome in which a dementing illness begins with visual symptoms. Initially,\\u000a the problem may seem to be loss of elementary vision, but over time the patient develops features of visual agnosia, topographical\\u000a difficulty, optic ataxia, simultanagnosia, ocular apraxia (Balint’s syndrome), alexia, acalculia, right-left confusion, and\\u000a agraphia (Gerstmann’s syndrome), and later a more generalized

Howard S. Kirshner; Patrick J. M. Lavin

2006-01-01

216

Posterior atlantoaxial arthrodesis. A simplified method.  

PubMed

A simplified method of posterior atlantoaxial arthrodesis allowing immediate stabilization and mobilization is described. This method of fixation has been used since 1984 in 33 cases, with the indications being nonunion of odontoid peg fractures, atlantoaxial dislocation, and other traumatic conditions about the axis. A solid fusion was noted in all 33 patients by 3 months postsurgery, and the complication rate was minimal. This method of atlantoaxial arthrodesis is simple, allows immediate mobilization, controls rotation and lateral bending, and is inexpensive. PMID:1948372

Rodrigues, F A; Hodgson, B F; Craig, J B

1991-08-01

217

Posterior approach to ventrally located spinal meningiomas  

PubMed Central

For the resection of anteriorly located meningiomas, various approaches have been used. Posterior approach is less invasive and demanding; however, it has been associated with increased risk of spinal cord injury. We evaluated ten consecutive patients that underwent surgery for spinal meningiomas. All patients were preoperative assessed by neurological examination, computed tomography and magnetic resonance imaging. All tumors were ventrally located and removed via a posterior approach. Transcranial motor-evoked potentials (TcMEPs), somatosensory-evoked potential (SSEP) and free running electromyography (EMG) were monitored intraoperative. Postoperative all patients had regular follow-up examinations. There were four males and six females. The mean age was 68.2 years (range 39–82 years). In nine out of ten cases, the tumor was located in the thoracic spine. A case of a lumbar meningioma was recorded. The most common presenting symptom was motor and sensory deficits and unsteady gait, whereas no patient presented with paraplegia. All meningiomas were operated using a microsurgical technique via a posterior approach. During the operation, free running EMG monitoring prompted a surgical alert in case of irritation, whereas TcMEP and SSEP amplitudes remained unchanged. Histopathology revealed the presence of typical (World Health Organisation grade I) meningiomas. The mean Ki-67/MIB-1 index was 2.75% (range 0.5–7). None of our patients sustained a transient or permanent motor deficit. After a mean follow-up period of 26 months (range 56–16 months), no tumor recurrence and no instability were found. Posterior approach for anteriorly located meningiomas is a safe procedure with the use of intraoperative monitoring, less invasive and well-tolerated especially in older patients. Complete tumor excision can be performed with satisfactory results. PMID:20127494

Voulgaris, Spyridon; Mihos, Evaggelos; Karagiorgiadis, Dimitrios; Zigouris, Andreas; Fotakopoulos, George; Drosos, Dimitrios; Pahaturidis, Dimitrios

2010-01-01

218

Material Properties of the Posterior Human Sclera?  

PubMed Central

To characterize the material properties of posterior and peripapillary sclera from human donors, and to investigate the macro- and micro-scale strains as potential control mechanisms governing mechanical homeostasis. Posterior scleral shells from 9 human donors aged 57–90 years were subjected to IOP elevations from 5 to 45 mmHg and the resulting full-field displacements were recorded using laser speckle interferometry. Eye-specific finite element models were generated based on experimentally measured scleral shell surface geometry and thickness. Inverse numerical analyses were performed to identify material parameters for each eye by matching experimental deformation measurements to model predictions using a microstructure-based constitutive formulation that incorporates the crimp response and anisotropic architecture of scleral collagen fibrils. The material property fitting produced models that fit both the overall and local deformation responses of posterior scleral shells very well. The nonlinear stiffening of the sclera with increasing IOP was well reproduced by the uncrimping of scleral collagen fibrils, and a circumferentially-aligned ring of collagen fibrils around the scleral canal was predicted in all eyes. Macroscopic in-plane strains were significantly higher in peripapillary region then in the mid-periphery. In contrast, the meso- and micro-scale strains at the collagen network and collagen fibril level were not significantly different between regions. The elastic response of the posterior human sclera can be characterized by the anisotropic architecture and crimp response of scleral collagen fibrils. The similar collagen fibril strains in the peripapillary and mid-peripheral regions support the notion that the scleral collagen architecture including the circumpapillary ring of collagen fibrils evolved to establish optimal load bearing conditions at the collagen fibril level. PMID:23684352

Grytz, Rafael; Fazio, Massimo A.; Girard, Michael J.A.; Libertiaux, Vincent; Bruno, Luigi; Gardiner, Stuart; Girkin, Christopher A.; Downs, J. Crawford

2013-01-01

219

Posterior Reversible Encephalopathy Syndrome Unmasking Acute Glomerulonephritis  

PubMed Central

Posterior reversible encephalopathy syndrome (PRES) is a recently described condition, wherein there is vasogenic oedema, seen on neuroimaging, predominantly over the parieto occipital regions of the cerebrum. Though, as the name implies, the condition is reversible, there may be fatalities and neurological sequelae. We are reporting a 9-year-old female child in whom the typical clinical and neurological findings of PRES were caused by an atypical presentation of acute glomerulonephritis. PMID:24596763

Kumar S., Sathish; M., Kumar; S., Shobhana; Sampath, Sowmya; Kasthuri, R. Kulandai

2014-01-01

220

Posterior right diagonal artery. An angiographic study.  

PubMed

The purpose of this prospectively performed study was the angiographic visualization of the posterior right diagonal artery (PRDA) and its differentiation from the epicardial branches of the right coronary artery (RCA), that is, the right marginal artery and the posterior descending artery (PDA). The authors prospectively studied the angiographic findings of 607 patients who underwent coronary angiography. The incidence of the angiographically demonstrated PRDA and its distinction from other epicardial branches arising from the distal third of the RCA was the main point of interest. Two types of PDA in those cases where PRDA was present were also demonstrated. Of the patients examined, 535 had dominant right coronary circulation, 59 had left dominant coronary circulation, and 13 had balanced coronary circulation. PRDA was present in 81 patients with right dominant coronary circulation (15.1%), in 2 patients with balanced coronary circulation (15.4%), and in none with left dominant coronary circulation. PRDA was revealed in 48 (40%) of 120 patients with a short PDA and in only 33 (8%) of 415 patients having long PDA. It is imperative to search always for the PRDA, when one is studying coronary arteriographies, bearing in mind that this artery may perfuse the inferior part of the posterior interventricular septum and the adjoining are, depending on the type of PDA. PMID:9269136

Margaris, N G; Kostopoulos, K G; Nerantzis, C E; Filippatos, G S; Kardaras, F G; Salahas, A I; Antonellis, J P; Ifandis, G P; Kranidis, A I; Tavernarakis, A G

1997-08-01

221

Posterior mini-incision hamstring harvest.  

PubMed

Many orthopedists looking for alternatives to autograft bone-patellar-tendon-bone grafts are uncertain of their ability to harvest a hamstring graft of adequate length. They may use an allograft instead for this reason despite recent reports of high failure rates. This article presents step-by-step instructions for a posterior mini-incision hamstring harvest that offers a safe and simple method of reliably harvesting sufficient hamstring for 4 or 6 strand repair, while using tiny incisions for excellent cosmesis and minimal pain. Access from the posterior mini-incision allows easy identification and differentiation of the semitendinosus and gracilis (Gr) tendons, as well as precise placement of the anterior mini-incision for tibial tunnel drilling and fixation. Most importantly sectioning of the intertendinous cross-connections is performed under easy direct vision posteriorly, instead of at a distance from the typical anterior incision under retractors. This prevents the tendons from being cut too short by the tendon stripper and is particularly useful in large patients. In addition to the surgical procedure, details on the required equipment are presented. PMID:20160624

Prodromos, Chadwick C

2010-03-01

222

Subarachnoid Hemorrhage Following Posterior Spinal Artery Aneurysm  

PubMed Central

Summary Isolated posterior spinal artery aneurysms are rare vascular lesions. We describe the case of a 43-year-old man presenting with spinal subarachnoid hemorrhage after a minor trauma who was found to have a dissecting aneurysm of a posterior spinal artery originating from the right T4 level. Endovascular treatment was not contemplated because of the small size of the feeding artery, whereas surgical resection was deemed more appropriate because of the posterolateral perimedullary location that was well appreciated on CT angiography. After surgical resection of the aneurysm the patient had a complete neurological recovery. In comparison to anterior spinal artery aneurysms whose pathogenesis is diverse, posterior spinal aneurysms are most often secondary to a dissection and represent false or spurious aneurysms. Although the definite diagnosis still requires spinal angiography, MRI and CT may better delineate the relationship of the aneurysm to the spinal cord in order to determine the best treatment method. Prompt treatment is recommended as they have high rebleeding and mortality rates. PMID:20642894

Geibprasert, S.; Krings, T.; Apitzsch, J.; Reinges, M.H.T.; Nolte, K.W.; Hans, F.J.

2010-01-01

223

Indocyanine green angiography in posterior uveitis.  

PubMed

Literature review for indocyanine green angiography and evaluate the role of indocyanine green angiogram (ICGA) in patients with posterior uveitis seen at a tertiary referral eye care centre. Detailed review of the literature on ICGA was performed. Retrospective review of medical records of patients with posterior uveitis and dual fundus and ICGA was done after institutional board approval. Eighteen patients (26 eyes) had serpiginous choroiditis out of which 12 patients had active choroiditis and six patients had healed choroiditis, six patients (12 eyes) had ampiginous choroiditis, six patients (12 eyes) had acute multifocal posterior placoid pigment epitheliopathy, eight patients (10 eyes) had multifocal choroiditis, four patients (eight eyes) had presumed ocular histoplasmosis syndrome, four patients (eight eyes) had presumed tuberculous choroiditis, two patients (four eyes) had multiple evanescent white dot syndrome and two patients (four eyes) had Vogt Koyanagi Harada (VKH) syndrome. The most characteristic feature noted on ICGA was the presence of different patterns of hypofluorescent dark spots, which were present at different stages of the angiogram. ICGA provides the clinician with a powerful adjunctive tool in choroidal inflammatory disorders. It is not meant to replace already proven modalities such as the fluorescein angiography, but it can provide additional information that is useful in establishing a more definitive diagnosis in inflammatory chorioretinal diseases associated with multiple spots. It still needs to be determined if ICGA can prove to be a follow up parameter to evaluate disease progression. PMID:23685486

Agrawal, Rupesh V; Biswas, Jyotirmay; Gunasekaran, Dinesh

2013-04-01

224

Indocyanine green angiography in posterior uveitis  

PubMed Central

Literature review for indocyanine green angiography and evaluate the role of indocyanine green angiogram (ICGA) in patients with posterior uveitis seen at a tertiary referral eye care centre. Detailed review of the literature on ICGA was performed. Retrospective review of medical records of patients with posterior uveitis and dual fundus and ICGA was done after institutional board approval. Eighteen patients (26 eyes) had serpiginous choroiditis out of which 12 patients had active choroiditis and six patients had healed choroiditis, six patients (12 eyes) had ampiginous choroiditis, six patients (12 eyes) had acute multifocal posterior placoid pigment epitheliopathy, eight patients (10 eyes) had multifocal choroiditis, four patients (eight eyes) had presumed ocular histoplasmosis syndrome, four patients (eight eyes) had presumed tuberculous choroiditis, two patients (four eyes) had multiple evanescent white dot syndrome and two patients (four eyes) had Vogt Koyanagi Harada (VKH) syndrome. The most characteristic feature noted on ICGA was the presence of different patterns of hypofluorescent dark spots, which were present at different stages of the angiogram. ICGA provides the clinician with a powerful adjunctive tool in choroidal inflammatory disorders. It is not meant to replace already proven modalities such as the fluorescein angiography, but it can provide additional information that is useful in establishing a more definitive diagnosis in inflammatory chorioretinal diseases associated with multiple spots. It still needs to be determined if ICGA can prove to be a follow up parameter to evaluate disease progression. PMID:23685486

Agrawal, Rupesh V; Biswas, Jyotirmay; Gunasekaran, Dinesh

2013-01-01

225

Electrocardiographic diagnosis of remote posterior wall myocardial infarction using unipolar posterior lead V9  

SciTech Connect

The accuracy of four electrocardiographic criteria for diagnosing remote posterior myocardial infarction was assessed prospectively in 369 patients undergoing exercise treadmill testing with thallium scintigraphy. Criteria included the following: (1) R-wave width greater than or equal to 0.04 s and R-wave greater than or equal to S-wave in V1; (2) R-wave greater than or equal to S-wave in V2; (3) T-wave voltage in V2 minus V6 greater than or equal to 0.38 mV (T-wave index); (4) Q-wave greater than or equal to 0.04 s in left paraspinal lead V9. Twenty-seven patients (7.3 percent) met thallium criteria for posterior myocardial infarction, defined as a persistent perfusion defect in the posterobase of the left ventricle. Sensitivities for the four criteria ranged from 4 to 56 percent, and specificities ranged from 64 to 99 percent. Posterior paraspinal lead V9 provided the best overall predictive accuracy (94 percent), positive predictive value (58 percent), and ability to differentiate patients with and without posterior myocardial infarction of any single criterion (p less than .0001). Combining the T-wave index with lead V9 further enhanced the diagnostic yield: the sensitivity for detecting posterior infarction by at least one of these criteria was 78 percent, and when both criteria were positive, specificity was 98.5 percent. It is concluded that a single, unipolar posterior lead in the V9 position is superior to standard 12-lead electrocardiographic criteria in diagnosing remote posterior myocardial infarction, and that combining V9 with the T-wave index maximizes the diagnostic yield.

Rich, M.W.; Imburgia, M.; King, T.R.; Fischer, K.C.; Kovach, K.L. (Jewish Hospital Washington University Medical Center, St. Louis (USA))

1989-09-01

226

LOCAL SENSITIVITY, FUNCTIONAL DERIVATIVES AND NONLINEAR POSTERIOR QUANTITIES  

E-print Network

LOCAL SENSITIVITY, FUNCTIONAL DERIVATIVES AND NONLINEAR POSTERIOR QUANTITIES by Sanjib Basu 1 University of Arkansas, Fayetteville, AR 72701 February, 1994 Abstract The local sensitivity of a posterior'echet and Gâ??ateaux derivatives (Huber (1981)) are thus used. Differentiability of ratio linear posterior

Basu, Sanjib

227

Simulating from the posterior density of Bayesian wavelet regression estimates  

E-print Network

Simulating from the posterior density of Bayesian wavelet regression estimates STUART BARBER;k, and updated by the observed data y to form a posterior for each coefficient. We then estimate each coefficient by the median of its posterior distribution and the inverse DWT is used upon the resulting estimates to form

Barber, Stuart

228

On Posterior Consistency in Selection Models Jaeyong Lee  

E-print Network

On Posterior Consistency in Selection Models Jaeyong Lee National Institute of Statistical Sciences process prior for the weight function is considered and it is proved that the posterior is consistent under the weak topology. Key words and Phrases: Dirichlet process, posterior consistency, selection

West, Mike

229

Posterior Covariance vs. Analysis Error Covariance in Data Assimilation  

E-print Network

Posterior Covariance vs. Analysis Error Covariance in Data Assimilation F.-X. Le Dimet(1), I (INRIA) Posterior covariance September 27, 2013 1 / 1 hal-00932577,version1-17Jan2014 #12;Overview Introduction Analysis Error Covariance via Hessian Posterior Covariance : A Bayesian approach Effective

Boyer, Edmond

230

A REVIEW OF CONSISTENCY AND CONVERGENCE OF POSTERIOR DISTRIBUTION  

E-print Network

A REVIEW OF CONSISTENCY AND CONVERGENCE OF POSTERIOR DISTRIBUTION By Subhashis Ghosal Indian and conver- gence of posterior distribution, that arise in Bayesian inference with large samples. Both and convergence of posterior distri- bution. This review is aimed for non-specialists. Technical conditions (like

Ghoshal, Subhashis

231

Power-Expected-Posterior Priors for Variable Selection  

E-print Network

Power-Expected-Posterior Priors for Variable Selection in Gaussian Linear Models D. Fouskakis , I. Expected-posterior priors are defined via imaginary training samples coming from a common underlying of the main advantages of the expected-posterior priors is that impropriety of baseline priors causes

Draper, David

232

On Posterior Consistency of Survival Models Yongdai Kim  

E-print Network

On Posterior Consistency of Survival Models Yongdai Kim Hankuk University of Foreign Studies, Korea. Jaeyong Lee National Institute of Statistical Science July 2, 1999 1 #12; Posterior consistency 2 Abstract Ghosh and Ramamoorthi (1995) studied the posterior consistency for survival mod­ els and showed

West, Mike

233

POSTERIOR MOMENTS OF THE CAUCHY DISTRIBUTION DAVID R. WOLF  

E-print Network

POSTERIOR MOMENTS OF THE CAUCHY DISTRIBUTION DAVID R. WOLF NASA Ames Research Center MS 269­2 Moffet Field CA 94035­1000 y Abstract. The posterior moments of parameters specifying distributions always exist. In this paper the posterior moments of the posi­ tion parameter of the Cauchy distribution

Wolf, David R.

234

Bayesian Posterior Comprehension via Message from Monte Carlo  

E-print Network

Bayesian Posterior Comprehension via Message from Monte Carlo Leigh J. Fitzgibbon, David L. Dowe an epitome, or brief summary, of a Bayesian posterior distribution - and then investigate a general solution comprehension, and fast approximation of posterior expectations. We call these the properties of Bayesian

Allison, Lloyd

235

Detecting Poor Convergence of Posterior Samplers due to Multimodality  

E-print Network

Detecting Poor Convergence of Posterior Samplers due to Multimodality Dawn B. Woodard Department techniques such as Markov chain Monte Carlo (MCMC). The convergence of the sampler to the posterior that this approach may be in- sufficient when the posterior distribution is multimodal­that lack of convergence due

West, Mike

236

Posterior Scleritis and Its Association with HLA B27 Haplotype  

Microsoft Academic Search

Background: Posterior scleritis is most commonly idiopathic but is also found in association with systemic disorders like rheumatoid arthritis. HLA B27 spondyloarthropathy manifests itself mainly in the form of anterior uveitis and anterior scleritis. Posterior scleritis has not been previously reported in patients with HLA B27 haplotype. We document the likely association between posterior scleritis and HLA B27 haplotype in

Arundhati Anshu; Soon Phaik Chee

2007-01-01

237

Probability and Geometry (elementary)  

NSDL National Science Digital Library

This lesson is designed to introduce students to geometric probability and fairness. This lesson provides links to discussions and activities related to geometric probability 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.

2010-01-01

238

Probability Forecasting in Meteorology  

Microsoft Academic Search

Efforts to quantify the uncertainty in weather forecasts began more than 75 years ago, and many studies and experiments involving objective and subjective probability forecasting have been conducted in meteorology in the intervening period. Moreover, the U.S. National Weather Service (NWS) initiated a nationwide program in 1965 in which precipitation probability forecasts were formulated on an operational basis and routinely

Allan H. Murphy; Robert L. Winkler

1984-01-01

239

Bayes' Theorem: Conditional Probabilities  

NSDL National Science Digital Library

To perform calculations using Bayes' theorem, enter the probability for one or the other of the items in each of the following pairs (the remaining item in each pair will be calculated automatically). A probability value can be entered as either a decimal fraction such as .25 or a common fraction such as 1/4

Lowry, Richard

240

Generic error probabilities  

Microsoft Academic Search

This paper presents new forms for an error probability associated, with the phase angle between two vectors perturbed by Gaussian noise. An interesting consequence of the underlying generic form is a new expression for the symbol error rate in MDPSK that is very similar to its counterpart for MPSK. The generic error probability is further shown to contain as special

R. F. Pawula

1999-01-01

241

Bayesian Probability Patrick Maher  

E-print Network

the inductive probability of the coin landing heads you need to know what the evidence is, not what about the world; to know the physical probability of the coin landing heads you need to know what. It is usually identified with the agent's degrees of belief but that interpretation is unsatisfactory because

Fitelson, Branden

242

Interactive Applet: Probability  

NSDL National Science Digital Library

This applet, created by McGraw-Hill Higher Education, is designed to help students visualize how observed probability approaches true probability as sample size increases by simulating rolling dice. It accompanies "Statistical Techniques in Business and Economics," but does not require use of the text. This is a fun lesson for students wanting to delve deeper into the world of statistics.

243

Probability and Geometry  

NSDL National Science Digital Library

This lesson is designed to introduce students to geometric probability with spinners and platonic solids. This lesson provides links to discussions and activities related to geometric probability 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

244

Probability: Playing with Fire  

NSDL National Science Digital Library

This lesson is designed to develop students’ understanding of chaos and experimental probability by repeatedly burning a simulated forest. The lesson provides links to discussions and activities related to chaos and probability as well as suggested ways to work them into the lesson.

2011-01-20

245

Statistical Applets: Probability  

NSDL National Science Digital Library

Created by authors Duckworth, McCabe, Moore and Sclove for W.H. Freeman and Co., this applet simulates flipping a coin to show how observed probability approaches true probability over time. It accompanies "Â?Â?Practice of Business Statistics," but can be used without this text. Even though brief, this is still a fine resource for an introductory statistics course.

Duckworth, William

246

Binomial Probability Model  

NSDL National Science Digital Library

This resource, created by the statistics departed at Western Michigan University, helps define and explain binomial probability. It includes examples and exercises for the learner which facilitate further understanding of the subject. Overall, this specific site is perfect for users studying statistics, more specifically probability testing.

Abebe, Asheber

247

Intro Probability Rabbits Description Predictions Ontology of Earthquake Probability: Metaphor  

E-print Network

Intro Probability Rabbits Description Predictions Ontology of Earthquake Probability: Metaphor be abandoned in favor of common sense. #12;Intro Probability Rabbits Description Predictions Earthquake not random. ­Wm. ShakesEarth #12;Intro Probability Rabbits Description Predictions Earthquake Poker

Stark, Philip B.

248

Data Analysis: Probability  

NSDL National Science Digital Library

This three lesson unit (15-page pdf) presents activities that guide students to understand the probability terms "certain" and "impossible". In each of the first two lessons students work as a class to conduct an experiment, complete sentences about the contents of a mystery bag, write probability statements, and express probability as common fractions. In the final lesson the class hears a story that contains both certain and impossible events. Students discuss which events are certain and impossible, and then construct a class book illustrating these concepts.

2009-01-01

249

The beginnings of probability  

NSDL National Science Digital Library

These pages present, in terms of a fictional story based on true events, the problem that inspired the development of mathematical probability in Renaissance Europe by French mathematicians Pierre de Fermat and Blaise Pascal. Two equally skilled players are interrupted while playing a game of chance for a certain amount of money. Given the score of the game at that point, how should the stakes be divided? Outlined here is, first, the particular solution and then the general solution based on a central concept of probability, equally probable outcomes.

The Math Forum

1998-01-01

250

Document Ranking with Quantum Probabilities  

E-print Network

Document Ranking with Quantum Probabilities Guido Zuccon School of Computing Science College for ranking documents. Quantum probability theory is used to estimate the probability of relevance Ranking Principle (PRP), which is based upon Kolmogorovian probability theory. Following our hypothesis

Collings, Iain B.

251

Experimental Probability in Elementary School  

ERIC Educational Resources Information Center

Concepts in probability can be more readily understood if students are first exposed to probability via experiment. Performing probability experiments encourages students to develop understandings of probability grounded in real events, as opposed to merely computing answers based on formulae.

Andrew, Lane

2009-01-01

252

The cognitive profile of posterior cortical atrophy  

Microsoft Academic Search

Abstract—Background:,Posterior cortical atrophy,(PCA) is a progressive,dementia,characterized,by prominent,disorders of higher visual processing, affecting both dorsal and ventral streams to cause Balint’s syndrome, alexia, and visual agnosia. Objective: To define the cognitive profile of PCA and compare to the typical, primary amnestic dementia of the Alzheimer’s,type,(DAT). Methods: The authors,used,standard,cognitive,tests and,a novel,battery,designed,to reflect dysfunction in both ventral (Object, Face & Color Agnosia Screen

P. McMonagle

2006-01-01

253

Large posterior vaginal cyst in pregnancy.  

PubMed

A 20-year-old primigravida presented in labour with a mass protruding from her vagina during uterine contractions. The mass was a large tense cyst measuring 8 × 8 cm arising from the posterior vaginal wall. The cyst was present since puberty but increased in size during pregnancy. It collapsed following aspiration and uneventful vaginal delivery was conducted. Following delivery, the cyst was excised and vaginal wall repaired. On histopathology the cyst was identified as a Müllerian cyst. The patient recovered and remained asymptomatic on follow-up. PMID:25604504

Lallar, Meenakshi; Nandal, Rajesh; Sharma, Deepak; Shastri, Sweta

2015-01-01

254

Endoscopic treatment of posterior ankle pain  

Microsoft Academic Search

Purpose  The aim of this study is to describe the indications for two-portal hindfoot endoscopy in the treatment of posterior ankle\\u000a compartment pathologies and to express the effectiveness of this technique by short- to mid-term outcomes on 59 consecutive\\u000a patients.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  In our institute, between 2003 and 2009, patients operated by single surgeon with hindfoot endoscopy were enrolled. The American\\u000a Orthopaedic Foot

Tahir Ogut; Egemen Ayhan; Kaan Irgit; Abdullah Ilker Sarikaya

2011-01-01

255

A PHILOSOPHICAL ESSAY PROBABILITIES.  

E-print Network

the Probability of the Judgments of Tribunals 132 CHAPTER XIV. Concerning Tables of Mortality, and the Mean of philosophers and direct it to a subject so worthy of engaging their minds. #12;CHAPTER II. CONCERNING

Mascarenhas, Walter Figueiredo

256

Assignment 3 Probability  

E-print Network

are not identical twins, the sex of each child is independent and each sex has probability 1/2. (a) In the cases population. Identical (monogygotic) twins make up 8% of all twins. Identical twins always have the same sex

Watkins, Joseph C.

257

Guide star probabilities  

NASA Technical Reports Server (NTRS)

Probabilities are calculated for acquiring suitable guide stars (GS) with the fine guidance system (FGS) of the space telescope. A number of the considerations and techniques described are also relevant for other space astronomy missions. The constraints of the FGS are reviewed. The available data on bright star densities are summarized and a previous error in the literature is corrected. Separate analytic and Monte Carlo calculations of the probabilities are described. A simulation of space telescope pointing is carried out using the Weistrop north galactic pole catalog of bright stars. Sufficient information is presented so that the probabilities of acquisition can be estimated as a function of position in the sky. The probability of acquiring suitable guide stars is greatly increased if the FGS can allow an appreciable difference between the (bright) primary GS limiting magnitude and the (fainter) secondary GS limiting magnitude.

Soneira, R. M.; Bahcall, J. N.

1981-01-01

258

Estimating the partial posterior distribution Bias and variance Numerical comparisons Approximate Bayesian Computation: a  

E-print Network

Estimating the partial posterior distribution Bias and variance Numerical comparisons Approximate posterior distribution Bias and variance Numerical comparisons Framework Two estimators of the posterior Numerical comparisons #12;Estimating the partial posterior distribution Bias and variance Numerical

Robert, Christian P.

259

Rock, Paper, Scissors Probability!  

NSDL National Science Digital Library

Students learn about probability through a LEGO® MINDSTORMS® NTX-based activity that simulates a game of "rock-paper-scissors." The LEGO robot mimics the outcome of random game scenarios in order to help students gain a better understanding of events that follow real-life random phenomenon, such as bridge failures, weather forecasts and automobile accidents. Students learn to connect keywords such as certainty, probable, unlikely and impossibility to real-world engineering applications.

AMPS GK-12 Program,

260

Overweighting of Small Probabilities  

Microsoft Academic Search

ABSTRACT The psychological impact of a ,low probability or rare event is typically large relative to that event’s actuarial likelihood. This overweighting follows a two-stage process. First, rare events tend to be overestimated because of the availability heuristic, anchoring on the “ignorance prior,” and coarse chance categories. Second, when making decisions, low probability events are overweighted,because ,of the ,“possibility effect”—decision

Zach Burns; Andrew Chiu; George Wu

261

Abstract Models of Probability  

Microsoft Academic Search

Probability theory presents a mathematical formalization of intuitive ideas of independent events and a probability as a measure of randomness. It is based on axioms 1-5 of A.N. Kolmogorov 1 and their generalizations 2. Different formalized refinements were proposed for such notions as events, independence, random value etc., 2,3, whereas the measure of randomness, i.e. numbers from [0,1], remained unchanged.

V. M. Maximov

2001-01-01

262

The Probability Factor  

NSDL National Science Digital Library

In this activity, students learn that probability is a way of measuring the chance of something happening. Students make predictions and match predictions with data, using a "probability tester" made from two golf tees. The activity includes a student data sheet. The resource is part of the teacher's guide accompanying the video, NASA SCI Files: The Case of the Phenomenal Weather. Lesson objectives supported by the video, additional resources, teaching tips and an answer sheet are included in the teacher's guide.

2012-08-03

263

Replacement and Probability  

NSDL National Science Digital Library

This lesson is designed to develop students' understanding of sampling with and without replacement and its effects on the probability of drawing a desired object. The lesson provides links to discussions and activities related to replacement and probability as well as suggested ways to work them into the lesson. Finally, the lesson provides links to follow-up lessons that are designed to be used in succession with the current one.

2011-01-20

264

Potential acuity meter for predicting visual acuity after Nd:YAG posterior capsulotomy  

SciTech Connect

We studied 30 patients with opacifications of the posterior capsule to determine if the potential acuity meter (PAM) could accurately predict final visual outcome after Nd:YAG discussion. The final visual acuity was within one line of the PAM prediction in 22 of 30 patients (73%), better by two or more lines in seven patients (23%), and worse in one patient (4%) by two lines. Although in thicker capsules the final acuity was occasionally better than the PAM prediction, the rates of false negative and false positive predictions were very low. Mild cystoid macular edema (3 patients), age-related macular degeneration (3 patients), intraocular lens status, and level of initial acuity did not diminish PAM accuracy. The PAM effectively predicts final visual acuity after YAG posterior capsulotomy, when used in a patient, unhurried manner.

Smiddy, W.E.; Radulovic, D.; Yeo, J.H.; Stark, W.J.; Maumenee, A.E.

1986-03-01

265

Elastic properties of human posterior eye.  

PubMed

This study examines the elastic properties of the human posterior retina, choroid, and sclera. Twenty-four human eyes from 30- to 74-year-old donors were obtained from an eye bank. Vertically and horizontally oriented tissue strips of the retina, choroid, and sclera (ideally n?=?12 in each group) were harvested from the posterior eyes. Their thicknesses were estimated optically. The samples were stretched at 1 mm/s in 37°C saline. Stress and strain were obtained from the mechanical tests, and then the transition stress, transition strain, toe modulus, and heel modulus were calculated. Statistical analysis was performed for comparison between groups. Linear regression analyses were used to explore the relationship between the mechanical parameters and age. We found that the stress-strain relationship of the retina, choroid, and sclera were nonlinear. Except for the retinal transition strain (p?=?0.0124), no statistical difference was found between the vertical and horizontal meridian in the mechanical parameters (p?>?0.05). Furthermore, weak relationship was observed between some of the mechanical parameters and the donors' age. Our results suggest that there is significant anisotropy in the retina, and mechanical properties of each layer may change with age. PMID:23852923

Chen, Kinon; Rowley, Adrian P; Weiland, James D; Humayun, Mark S

2014-06-01

266

Management of an Uncomplicated Posterior Elbow Dislocation  

PubMed Central

Objective: To present a case of an uncomplicated posterior elbow dislocation in a US World Cup athlete and discuss her rehabilitation. Background: Traditional protocol for management of this injury has been splint immobilization for several weeks, but research suggests a shortened duration of immobilization and early active motion. Differential Diagnosis: Elbow dislocation with possible fracture. Treatment: The dislocation was reduced and a compression bandage and sling were applied. The sports medicine staff and athlete determined that rehabilitation would involve limited immobilization with a posterior splint. Also, active range-of- motion exercises were to be incorporated early in the range-of- motion program to decrease pain at the articulation. Uniqueness: The athlete was not immobilized and her aggressive five-phase rehabilitation program progressed according to decrease in inflammation and increase in range of motion and strength. Conclusions: Shortened immobilization and return to World Championship competition 6 weeks postinjury had no longterm adverse effects on the athlete. ImagesFig 1.Fig 2.Fig 3.Fig 4.Fig. 5. PMID:16558436

Blackard, Douglas; Sampson, Jo-Ann

1997-01-01

267

Posterior subcapsular cataract and inhaled corticosteroid therapy.  

PubMed Central

BACKGROUND--Although posterior subcapsular cataract complicates both systemic and topical corticosteroid therapy, the literature on the effects of inhaled corticosteroids is conflicting. METHODS--One hundred and forty children and young adults on inhaled corticosteroids were examined by slit lamp ophthalmoscopy after pupillary dilatation; 103 had received one or more short courses (< or = 7 days) of oral corticosteroids in the management of acute asthmatic attacks and four had also received one or more prolonged courses (> or = 4 weeks) of alternate day oral corticosteroid therapy. RESULTS--Bilateral posterior subcapsular cataract was identified in one girl who had received several prolonged courses of oral corticosteroids, but was not identified in any other patient. CONCLUSIONS--There is no evidence to support the contention that inhaled corticosteroid therapy on its own, or in association with short courses of oral corticosteroid therapy, might cause cataracts. Although children receiving long term systemic corticosteroid therapy should be screened for cataracts, this is unnecessary in children on inhaled corticosteroids alone. PMID:7638813

Abuekteish, F.; Kirkpatrick, J. N.; Russell, G.

1995-01-01

268

Sampling Networks from Their Posterior Predictive Distribution  

PubMed Central

Recent research indicates that knowledge about social networks can be leveraged to increase efficiency of interventions (Valente, 2012). However, in many settings, there exists considerable uncertainty regarding the structure of the network. This can render the estimation of potential effects of network-based interventions difficult, as providing appropriate guidance to select interventions often requires a representation of the whole network. In order to make use of the network property estimates to simulate the effect of interventions, it may be beneficial to sample networks from an estimated posterior predictive distribution, which can be specified using a wide range of models. Sampling networks from a posterior predictive distribution of network properties ensures that the uncertainty about network property parameters is adequately captured. The tendency for relationships among network properties to exhibit sharp thresholds has important implications for understanding global network topology in the presence of uncertainty; therefore, it is essential to account for uncertainty. We provide detail needed to sample networks for the specific network properties of degree distribution, mixing frequency, and clustering. Our methods to generate networks are demonstrated using simulated data and data from the National Longitudinal Study of Adolescent Health. PMID:25339990

Goyal, Ravi; De Gruttola, Victor; Blitzstein, Joseph

2014-01-01

269

Hydatidosis of the liver and posterior mediastinum  

PubMed Central

Introduction Cystic echinococcus (CE) is an endemic zoonosis secondary to infection by the larval form of the cestode Echinococcus granulosus. An intermediate host, humans enter the organism’s life cycle by exposure to infected canid feces. The liver is the most common location of CE while mediastinal hydatid cysts are rarely reported. Presentation of case We report a case of synchronous CE of the liver and posterior mediastinum treated sequentially using chemotherapy, percutaneous aspiration with injection of a scolicidal agent and re-aspiration (PAIR) and then staged minimally-invasive surgeries. Discussion Synchronous CE involving the liver and posterior mediastinum is rare. The treatment of hydatid liver and mediastinal disease is multimodal including chemotherapy, percutaneous and laparoscopic or open surgical interventions. One option for controlled puncture of hepatic and mediastinal CE includes PAIR followed by surgery. Conclusion The sequential use of chemotherapy and PAIR followed by surgery provides another treatment strategy for management of CE. We believe this strategy may be used safely in locations without endemic CE, including most regions of the United States. PMID:25562598

Quail, Jacob F; Gramins, Daniel L; Dutton, William D

2014-01-01

270

Predicting Accurate and Actionable Static Analysis Warnings: An Experimental Approach  

E-print Network

[Probability and Statistics]: Correlation and regression analysis General Terms Experimentation, ReliabilityPredicting Accurate and Actionable Static Analysis Warnings: An Experimental Approach Joseph R, jdm}@google.com ABSTRACT Static analysis tools report software defects that may or may not be detected

Tomkins, Andrew

271

Accurate determination of inflationary perturbations  

E-print Network

We use a numerical code for accurate computation of the amplitude of linear density perturbations and gravitational waves generated by single-field inflation models to study the accuracy of existing analytic results based on the slow-roll approximation. We use our code to calculate the coefficient of an expansion about the exact analytic result for power-law inflation; this generates a fitting function which can be applied to all inflationary models to obtain extremely accurate results. In the appropriate limit our results confirm the Stewart--Lyth analytic second-order calculation, and we find that their results are very accurate for inflationary models favoured by current observational constraints.

Ian J Grivell; Andrew R Liddle

1996-07-18

272

Accurate Monitor 1.2  

NSDL National Science Digital Library

With many computer users developing their own Web sites, some of them may be interested in monitoring how search engines may be ranking their site. This latest edition of Accurate Monitor may prove useful, as it allows individuals to find the position of their Web site in search engines like Altavista and Google. Additionally, Accurate Monitor can generate advanced statistics and monitor plugins, along with providing a flexible interface system. This version of Accurate Monitor is compatible with all systems running Windows 95 and higher.

273

Prehension Movements in a Patient (AC) with Posterior Parietal Cortex Damage and Posterior Callosal Section  

ERIC Educational Resources Information Center

Prehension movements of the right hand were recorded in a right-handed man (AC), with an injury to the left posterior parietal cortex (PPC) and with a section of the left half of the splenium. The kinematic analysis of AC's grasping movements in direct and perturbed conditions was compared to that of five control subjects. A novel effect in…

Frak, Victor; Paulignan, Yves; Jeannerod, Marc; Michel, Francois; Cohen, Henri

2006-01-01

274

Peripapillary and Posterior Scleral Mechanics, Part II – Experimental and Inverse Finite Element Characterization  

PubMed Central

Background The posterior sclera likely plays an important role in the development of glaucoma and accurate characterization of its mechanical properties is needed to understand its impact on the more delicate optic nerve head – the primary site of damage in the disease. Method of Approach The posterior scleral shells from both eyes of one rhesus monkey were individually mounted on a custom-built pressurization apparatus. Intraocular pressure was incrementally increased from 5 to 45 mm Hg, and the 3-D displacements were measured using electronic speckle pattern interferometry. Finite element meshes of each posterior scleral shell were reconstructed from data generated by a 3D digitizer arm (shape) and a 20 MHz ultrasound transducer (thickness). An anisotropic hyperelastic constitutive model described in a companion paper [1], which includes stretch-induced stiffening and multi-directional alignment of the collagen fibers, was applied to each reconstructed mesh. Surface node displacements of each model were fitted to the experimental displacements using an inverse finite element method, which estimated a unique set of thirteen model parameters. Results The predictions of the proposed constitutive model matched the 3-D experimental displacements well. In both eyes, the tangent modulus increased dramatically with IOP, which indicates that the sclera is mechanically nonlinear. The sclera adjacent to the optic nerve head, known as the peripapillary sclera, was thickest and exhibited the lowest tangent modulus, which might have contributed to the uniform distribution of the structural stiffness for each entire scleral shell. Conclusions Posterior scleral deformation following acute IOP elevations appears to be nonlinear and governed by the underlying scleral collagen microstructure as predicted by finite element modeling. The method is currently being used to characterize posterior scleral mechanics in normal (young and old), early and moderately glaucomatous monkey eyes. PMID:19388782

Girard, Michaël J. A.; Downs, J. Crawford; Bottlang, Michael; Burgoyne, Claude F.; Suh, J-K. Francis

2009-01-01

275

Paediatric epilepsy surgery in the posterior cortex: a study of 62 cases.  

PubMed

Past surgical series have emphasized the diagnostic complexity of posterior cortex epilepsy. Available data are sparse, especially in children, and most published series report a high number of surgical failures and post-operative neurological deficits. In this article, we present a paediatric cohort of 62 children who underwent surgery for drug resistant posterior cortex epilepsy before the age of 16 years with a mean post-operative follow-up of 6.94 years (range: 2-16). Mean age at epilepsy onset was 3.2 years and 28 children (45%) had onset before 1 year of age. The mean age at surgery was 7.9 years (range: 1-16). Daily seizures were present in 63% of children. MRI was positive in 58 cases (93.5%) and invasive stereo-EEG was judged mandatory in 24/62 (39%) of patients. Surgery was confined to the parietal lobe in 11 children, the occipital lobe in 8, the occipito-parietal region in four, the occipito-temporal region in 18, and involved both the temporal and parietal lobes in the remaining 21. Following surgery, 53 subjects (85.5%) remained seizure-free and among those who underwent a SEEG procedure, 75% achieved seizure freedom. Focal cortical dysplasia was the most frequent histopathological diagnosis (50%), followed by tumoural (24%) and gliotic lesions (14.5%). An older age at epilepsy onset, the presence of a rather restricted epileptogenic area, and a complete resection of the epileptogenic zone were predictive of a favourable surgical outcome. These results demonstrate that a good surgical outcome is possible in children with drug resistant posterior cortex epilepsy. Accurate analysis of the chronology of ictal semiology and electrophysiological features, viewed in the context of the complete electroclinical pattern, provides a topographical orientation for posterior cortex epilepsy and, together with the presence of a lesion detectable on imaging, may improve the rate of surgical success of posterior cortex epilepsy at paediatric age. PMID:24853765

Liava, Alexandra; Mai, Roberto; Tassi, Laura; Cossu, Massimo; Sartori, Ivana; Nobili, Lino; Lo Russo, Giorgio; Francione, Stefano

2014-06-01

276

The perception of probability.  

PubMed

We present a computational model to explain the results from experiments in which subjects estimate the hidden probability parameter of a stepwise nonstationary Bernoulli process outcome by outcome. The model captures the following results qualitatively and quantitatively, with only 2 free parameters: (a) Subjects do not update their estimate after each outcome; they step from one estimate to another at irregular intervals. (b) The joint distribution of step widths and heights cannot be explained on the assumption that a threshold amount of change must be exceeded in order for them to indicate a change in their perception. (c) The mapping of observed probability to the median perceived probability is the identity function over the full range of probabilities. (d) Precision (how close estimates are to the best possible estimate) is good and constant over the full range. (e) Subjects quickly detect substantial changes in the hidden probability parameter. (f) The perceived probability sometimes changes dramatically from one observation to the next. (g) Subjects sometimes have second thoughts about a previous change perception, after observing further outcomes. (h) The frequency with which they perceive changes moves in the direction of the true frequency over sessions. (Explaining this finding requires 2 additional parametric assumptions.) The model treats the perception of the current probability as a by-product of the construction of a compact encoding of the experienced sequence in terms of its change points. It illustrates the why and the how of intermittent Bayesian belief updating and retrospective revision in simple perception. It suggests a reinterpretation of findings in the recent literature on the neurobiology of decision making. PMID:24490790

Gallistel, C R; Krishan, Monika; Liu, Ye; Miller, Reilly; Latham, Peter E

2014-01-01

277

Posterior cortical atrophy: visuomotor deficits in reaching and grasping  

PubMed Central

Posterior Cortical Atrophy (PCA) is a rare clinical syndrome characterized by the predominance of higher-order visual disturbances such as optic ataxia, a characteristic of Balint's syndrome. Deficits result from progressive neurodegeneration of occipito-temporal and occipito-parietal cortices. The current study sought to explore the visuomotor functioning of four individuals with PCA by testing their ability to reach out and grasp real objects under various viewing conditions. Experiment 1 had participants reach out and grasp simple, rectangular blocks under visually- and memory-guided conditions. Experiment 2 explored participants' abilities to accurately reach for objects located in their visual periphery. This investigation revealed that PCA patients demonstrate many of the same deficits that have been previously reported in other individuals with optic ataxia, such as “magnetic misreaching”—a pathological reaching bias toward the point of visual fixation when grasping peripheral targets. Unlike many other individuals with optic ataxia, however, the patients in the current study also show symptoms indicative of damage to the more perceptual stream of visual processing, including abolished grip scaling during memory-guided grasping and deficits in face and object identification. These investigations are the first to perform a quantitative analysis of the visuomotor deficits exhibited by patients with PCA. Critically, this study helps characterize common symptoms of PCA, a vital first step for generating effective diagnostic criteria and therapeutic strategies for this understudied neurodegenerative disorder. PMID:23801956

Meek, Benjamin P.; Shelton, Paul; Marotta, Jonathan J.

2013-01-01

278

Venn Diagrams and Probability  

NSDL National Science Digital Library

This applet lets you highlight the set A, the set B, the set C, the universal set S, the empty set {}, the complement of A (Ac), the complement of B (Bc), the complement of C (Cc), the intersection of A and B (AB), the union of A and B (A or B), the intersection of the complement of A with B (AcB), the intersection of A with the complement of B (ABc), the intersection of A, B, and C (ABC), the union of A, B, and C (A or B or C), the intersection of Ac and B and C (AcBC), and the union of the complement of A and the intersection of B and C (Ac or BC). One can think of the relative area of a set to the area of S as a probability. You can drag the events A, B, and C around, which changes the probability of their intersection and of their union. This applet displays six conditional probabilities: P(A|B), P(Ac|B), P(B|A), P(A|BC), P(Ac|BC), and P(A|(B or C)). When the corresponding checkbox is ticked, the events whose probabilities are involved in computing the conditional probability are highlighted in contrasting colors.

Stark, Philip B.

279

[Is posterior lumbar epidural space partitioned?].  

PubMed

The anatomy of the posterior lumbar epidural space (PLES) has been extensively studied. Besides the anatomists, surgeons, radiologists and anaesthetists have taken an interest in this. However, because each one has considered the PLES from his own specialist field, descriptions are not always concordant. In particular, the reality of a medial partition in the PLES has been suggested by epidurography and intraoperative observations. Lewit and Sereghy and Luyendijk opened the debate by reporting, on antero-posterior epidurographic films, a clear-cut, medial, vertical and narrow picture which partitioned the PLES. However, this was not constant. Savolaine et al. also recognized this partition on epidurographic CT scans. During laminectomies, Luyendijk has taken photographs of a medial fold of the dura mater which appeared to hold it to the posterior vertebral arch, being collapsed on either side of the midline. He named it "plica mediana dorsalis durae matris" (PMD). Several anaesthetists considered that this could explain why epidural analgesia sometimes acted on one side only. Husemeyer and White, and Harrison et al., have tried to confirm this experimentally by making casts with polymerizing resins in cadavers. They did not get very convincing results. Blomberg also tried to see this space by epiduroscopy in the cadaver. Unfortunately, for technical reasons, his photographs were of poor quality. He, however, reported having seen each time the PMD and a band of connective tissue fixing it to the vertebral arch in the midline. However, all these anatomical studies used methods which alter the natural structures. Their results are therefore questionable. The PLES is a virtual space. Histological studies have shown that it is filled with fatty tissue between the dura and the vertebral arch. It is therefore conceivable that any liquid injected into the PLES, such as contrast medium or local anaesthetic, must push back the dura, the only tissue which can move to give it any room. The fatty tissue could therefore be compressed and take any of the shapes which have been described on epidurography. On the other hand, should it be torn, it seems this fatty tissue could make up these haphazard fibrous tracts tensed between the dura and the vertebral arch, such as described in classical anatomy, as Bonica recalled. These can be clearly seen during surgical and anatomical dissections, and during endoscopies carried out on cadavers with sufficient optical means, as opposed to the medial fibrous band fixing the dura to the vertebral arch.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:1443817

Morisot, P

1992-01-01

280

Data Analysis and Probability  

NSDL National Science Digital Library

With these activities you are going to brush up your data analysis skills and practice finding the probability of events! These games are fun, but you will be surprised how much you learn! Practice finding the mean, median, mode and range with this fun game! Determine the probability that an event will occur or an object will be selected! Review the information on reading bar graphs with this game and practice working with bar graphs when you are done. To see great examples of how data can be displayed, take some of the surveys on ...

Ms. Jackson

2008-03-24

281

Parametric Probability Distributions  

NSDL National Science Digital Library

The Environmental Protection Agency (EPA) has released a series of Parametric Probability Distributions to be used in conjunction with the previously released Exposure Factors Handbook. Whereas the Exposure Factors Handbook provides summaries of available statistical data on several factors used in assessing human exposure to toxic chemicals, the Parametric Probability Distributions document summarizes procedures to fit distributions to some of those data. Three factors (tap water intake, population mobility, and inhalation rules) are considered as test cases in the models, and recommendations are made for models that provide the best fit. For students of statistics, these documents could be used as supplemental examples, illustrating methods useful for addressing actual statistical challenges.

Myers, Lawrence.

2000-01-01

282

Data Analysis and Probability  

NSDL National Science Digital Library

Education in a free society must prepare citizens to make informed choices in all areas of their lives. They must be able to grasp the information being presented, analyze it, and make reasoned decisions. To accomplish these goals, students learn to collect, organize, and display relevant data to answer questions that can be addressed with data; use appropriate statistical methods and predictions that are based on data; develop and evaluate inferences and predictions that are based on data; and apply basic concepts of probability. Probability is the study of chance and the possibility that an event will occur.

2014-09-18

283

Minimally invasive surgical approach to treat posterior urethral diverticulum  

PubMed Central

Urethral diverticulum is a localized saccular or fusiform out-pouching of the urethra. It may occur at any point along the urethra in both male and females. Male urethral diverticulum is rare, and could be either congenital or acquired, anterior or posterior. The mainstay treatment of posterior urethral diverticulum (PUD) is the open surgical approach. Here we discuss our minimally invasive surgical approach (MIS) in managing posterior urethral diverticulum.

Alsowayan, Ossamah; Almodhen, Fayez; Alshammari, Ahmed

2015-01-01

284

List of Topics Probability Basic Course I. Probability Space  

E-print Network

theorems, applications. [Radon-Nikodym theorem] Reference Ash, R.B. Real Analysis and Probability Billingsley, p. Probability and Measure Dudley, R.M. Real Analysis and Probability Fristedt, R.M., Gray, L

285

[Posterior polymorphous corneal dystrophy--case report].  

PubMed

Posterior polymorphous corneal dystrophy (PPCD) is a rare, bilateral, congenital disorder. It affects endothelial cells and Descemet's membrane. Slit lamp examination of PPCD shows characteristic bilateral endothelial bands, vesicles, and polymorphous opacities at the level of Descemet's membrane and endothelium, which can be accompanied by iridocorneal peripheral adhesions, iris atrophy, and corectopia. The clinical phenotype of PPCD can vary from relatively benign Descemet's thickening to severe progression towards vision loss from corneal edema or consecutive glaucoma. We present a case report of a 7-years old male patient with left eye corneal edema. Diagnosis of PPCD is made by slit-lam examination accompanied by anterior segment optical coherence tomography (AS OCT), and specular microscopy examination. Examination also revealed corneal changes in left eye of 32-years old patient's mother. PMID:19673448

Nowi?ska, Anna; Wylga?a, Edward; Dobrowolski, Dariusz

2009-01-01

286

Allocentric spatial neglect with posterior cortical atrophy.  

PubMed

Patients with posterior cortical atrophy (PCA) have been reported to have neglect in the egocentric/ body-centered reference frame. This report describes a woman with PCA who had a right-sided stimulus-based form of allocentric visual neglect on cancellation, reading, and drawing tests. Her brain imaging revealed left parietal atrophy. The pathophysiology of this disorder may be related to an impairment of the ventral "what" stream's ability to interact with the dorsal "where" stream that mediates the allocation of spatial attention, or a deficit in the systems that allocate contralateral focal attention. Further research is needed to better understand the mechanisms of this disorder and to optimally treat it. PMID:24679168

Zilli, Eduardo M; Heilman, Kenneth M

2015-01-01

287

Surgery for posterior communicating artery aneurysms.  

PubMed

The most common site of internal carotid artery (ICA) aneurysms is at the posterior communicating artery (PComA) junction. Although ICA aneurysm surgery carries substantial risk, the ultimate outcome of patients with PComA aneurysms is better than those with aneurysms in other locations. The rate of successful surgical outcome increases when precise knowledge of the anatomy and understanding of the hazards associated with aneurysms in this region are combined with a well organized plan for the surgical approach. This article will describe details of the preoperative considerations, operative techniques, and surgical results for aneurysms arising at the ICA-PComA junction based on the 25-year personal experience of the senior author, comprising a total of 424 surgical cases. PMID:12648909

Lee, Kyu Chang; Lee, Kyu Sung; Shin, Yong Sam; Lee, Jae Whan; Chung, Su Kyoung

2003-02-01

288

Asymptomatic posterior mediastinal teratoma diagnosed incidentally.  

PubMed

We present a young patient with occasional chest pain and an incidentally found posterior mediastinal mass on radiology which was confirmed as mature teratoma on histopathology. The gross specimen received in the department of pathology was globular measuring 9.0×7.0×5.5 cm and varying in consistency from soft cystic to firm. Cut surface showed numerous hair entangled in pultaceous material. Representative sections were taken and stained with H&E stain. Histopathology revealed haphazardly distributed mature derivatives of all the three germ layers comprising of epidermis, pilo sebaceous units, nerve bundles (ectodermal), cartilage, bone, salivary gland clusters, blood vessels, muscle bundles, fibrous tissue infiltrated by foreign body giant cells, lymphoid follicles (mesodermal) and pseudostratified columnar epithelium (mesodermal), thus establishing the diagnosis of mature teratoma. PMID:24654248

Jaiswal, Riddhi; Rani, Poonam; Devenraj, Vijayant

2014-01-01

289

Iodine-125 radiation of posterior uveal melanoma  

SciTech Connect

Twenty-eight cases of posterior choroidal melanoma were treated with iodine-125 in gold eye plaques. Eleven cases were located within 3.0 mm of the optic nerve (group A), nine were within 3.0 mm of the fovea (group B), and eight were within 3.0 mm of the optic nerve and fovea (group C). The mean follow-up of group A was 46.3 months; group B, 25.5 months; and group C, 42.7 months. Complications included macular edema, cataract and tumor growth. Visual acuity remained within two lines of that tested preoperatively for 4 of 11 patients in group A, 4 of 9 in group B, and 5 of 8 in group C. These results with iodine-125 suggest it as an appropriate treatment for patients with choroidal melanoma located near optic nerve and/or macula.

Packer, S.

1987-12-01

290

Posterior Cruciate Ligament: Focus on Conflicting Issues  

PubMed Central

There is little consensus on how to optimally reconstruct the posterior cruciate ligament (PCL) and the natural history of injured PCL is also unclear. The graft material (autograft vs. allograft), the type of tibial fixation (tibial inlay vs. transtibial tunnel), the femoral tunnel position within the femoral footprint (isometric, central, or eccentric), and the number of bundles in the reconstruction (1 bundle vs. 2 bundles) are among the many decisions that a surgeon must make in a PCL reconstruction. In addition, there is a paucity of information on rehabilitation after reconstruction of the PCL and posterolateral structures. This article focused on the conflicting issues regarding the PCL, and the scientific rationales behind some critical points are discussed. PMID:24340144

Lee, Yong Seuk

2013-01-01

291

Dehiscence of the posterior semicircular canal.  

PubMed

Semicircular canal dehiscence (SCD) is a condition of the inner ear wherein the temporal bone adjacent to the vestibular apparatus thins or erodes completely. It has no clear epidemiological predisposing factors that have been identified to date. Its diagnosis is made difficult by a clinical presentation that often overlaps with other pathologies of the ear. Symptoms of SCD are believed to result from a "third-window" phenomenon, which disrupts the transmission of acoustic energy in the inner ear. Symptoms, when present, may change or worsen over time, confounding the diagnosis. We present a case of SCD of the posterior canal that mimicked Meniere's disease for several decades. We also discuss the clinical findings that may steer clinical suspicion towards this diagnosis. PMID:25241030

Peress, Lilia; Telian, Steven A; Srinivasan, Ashok

2015-01-01

292

Diagnostics for insufficiencies of posterior calculations in Bayesian signal inference.  

PubMed

We present an error-diagnostic validation method for posterior distributions in Bayesian signal inference, an advancement of a previous work. It transfers deviations from the correct posterior into characteristic deviations from a uniform distribution of a quantity constructed for this purpose. We show that this method is able to reveal and discriminate several kinds of numerical and approximation errors, as well as their impact on the posterior distribution. For this we present four typical analytical examples of posteriors with incorrect variance, skewness, position of the maximum, or normalization. We show further how this test can be applied to multidimensional signals. PMID:24329375

Dorn, Sebastian; Oppermann, Niels; Ensslin, Torsten A

2013-11-01

293

Imprecise probabilities and scenarios  

Microsoft Academic Search

This paper argues that imprecise probability can be used to describe uncertainty about scenarios. Scenarios are conceptualized as written descriptions of potential future worlds that are based on assessments of economic, political, social, technological, and environmental trends [This description of scenarios follows that provided by Peter Schwartz. P. Schwartz [9], The Art of the Long View, Doubleday, New York, 1991

Bruce Tonn

2005-01-01

294

Logic and probability  

E-print Network

The propositional logic is generalized on the real numbers field. The logical analog of the Bernoulli independent tests scheme is constructed. The variant of the nonstandard analysis is adopted for the definition of the logical function, which has all properties of the classical probability function. The logical analog of the Large Number Law is deduced from properties of this function.

G. A. Quznetsov

2010-09-14

295

Approximating Integrals Using Probability  

ERIC Educational Resources Information Center

As part of a discussion on Monte Carlo methods, which outlines how to use probability expectations to approximate the value of a definite integral. The purpose of this paper is to elaborate on this technique and then to show several examples using visual basic as a programming tool. It is an interesting method because it combines two branches of…

Maruszewski, Richard F., Jr.; Caudle, Kyle A.

2005-01-01

296

Probability and Cancer Clusters  

ERIC Educational Resources Information Center

Recently there have been several news items about possible cancer clusters in the Australian media. The term "cancer cluster" is used when an unusually large number of people in one geographic area, often a workplace, are diagnosed with cancer in a short space of time. In this paper the authors explore this important health issue using probability

Hamilton-Keene, Rachael; Lenard, Christoper T.; Mills, Terry M.

2009-01-01

297

DISCUSS: Probability with Dice  

NSDL National Science Digital Library

This module, by Neville Hunt and Nicki Cologne-Brookes of Coventry University, teaches probability through dice simulations. Students will use Excel spreadsheets to simulate experiments of rolling 1 die, taking the sum of 2 dice, taking the difference of 2 dice, and rolling many dice. Instructions for creating a dice simulation in Excel are also given.

Cologne-Brookes, Nicki

298

Jonny Heeley's Masterclass - Probability  

NSDL National Science Digital Library

In this video, award-winning Jonny Heeley offers some inspiring ways of simplifying probability. He uses a variety of games and challenges to excite and entertain his group of students. His ideas also provide teachers with some accessible new methods of teaching the subject.

teachers.tv

2009-02-17

299

Univariate Probability Distributions  

ERIC Educational Resources Information Center

We describe a web-based interactive graphic that can be used as a resource in introductory classes in mathematical statistics. This interactive graphic presents 76 common univariate distributions and gives details on (a) various features of the distribution such as the functional form of the probability density function and cumulative distribution…

Leemis, Lawrence M.; Luckett, Daniel J.; Powell, Austin G.; Vermeer, Peter E.

2012-01-01

300

Assignment 3 Probability  

E-print Network

of tagged fish in the second capture. 2. Hemophilia A is a sex linked recessive trait on the X chromosome for hemophilia What fraction of the male popu- lation have hemophilia? (b) A female has hemophilia if she received two alleles for hemophilia. Assuming that the probability of receiving the allele is 0

Watkins, Joseph C.

301

Tree Diagrams and Probability  

NSDL National Science Digital Library

This lesson is designed to develop students' ability to create tree diagrams and figure probabilities of events based on those diagrams. This lesson provides links to discussions and activities related to tree diagrams as well as suggested ways to work them into the lesson. Finally, the lesson provides links to follow-up lessons designed for use in succession with the current one.

2011-01-20

302

Probability Plot Experiment  

NSDL National Science Digital Library

This resource consists of a Java applet and Expository text. The applet simulates the probability plot that compares the empirical quantiles of a sample from a sampling distribution to the distribution quantiles of a test distribution. The sampling distribution, test distribution, and sample size can be specified.

Kyle Siegrist

303

A Unifying Probability Example.  

ERIC Educational Resources Information Center

Presents an example from probability and statistics that ties together several topics including the mean and variance of a discrete random variable, the binomial distribution and its particular mean and variance, the sum of independent random variables, the mean and variance of the sum, and the central limit theorem. Uses Excel to illustrate these…

Maruszewski, Richard F., Jr.

2002-01-01

304

Diagnosis of posterior cortical atrophy delayed by coexisting Fuchs' Endothelial Corneal Dystrophy.  

PubMed

Posterior cortical atrophy (PCA), also known as the visual variant of Alzheimer's Disease, is a rare neurodegenerative disorder that affects the visuospatial systems in its initial stages. Due to the rarity of this condition and the presence of relatively preserved memory during its early stages compared to other dementias, its accurate diagnosis can be delayed. When accompanied by a comorbid visual disorder, the diagnostic process becomes even more challenging. This study describes the disease course of a patient whose diagnosis of Fuchs' Endothelial Corneal Dystrophy served to delay an additional diagnosis of PCA, illustrating the necessity of careful scrutiny of symptom presentation and especially its course. PMID:24667904

Han, Dong Y; Shandera-Ochsner, Anne L; Bell, Brian D; Seeger, Susanne K

2014-03-01

305

Protesi di ginocchio a stabilizzazione posteriore e a conservazione del legamento crociato posteriore. Esame comparativo  

Microsoft Academic Search

L’artroprotesi totale di ginocchio si è oramai dimostrata un presidio efficace nel ridurre l’entità del dolore ed incrementare\\u000a le capacità funzionali. Dati ottenuti da studi eseguiti sia su artroprotesi postero-stabilizzate (PS) che su quelle a conservazione\\u000a del crociato posteriore (PCR) hanno messo in evidenza risultati rilevanti anche a lungo termine. Ancora oggi esiste, tuttavia,\\u000a notevole controversia su quale sia il

G. Cerulli; A. Caraffa; P. Antinolfi; G. Zamarra

306

Hf Transition Probabilities and Abundances  

E-print Network

Radiative lifetimes from laser-induced fluorescence measurements, accurate to about +/- 5 percent, are reported for 41 odd-parity levels of Hf II. The lifetimes are combined with branching fractions measured using Fourier transform spectrometry to determine transition probabilities for 150 lines of Hf II. Approximately half of these new transition probabilities overlap with recent independent measurements using a similar approach. The two sets of measurements are found to be in good agreement for measurements in common. Our new laboratory data are applied to refine the hafnium photospheric solar abundance and to determine hafnium abundances in 10 metal-poor giant stars with enhanced r-process abundances. For the Sun we derive log epsilon (Hf) = 0.88 +/- 0.08 from four lines; the uncertainty is dominated by the weakness of the lines and their blending by other spectral features. Within the uncertainties of our analysis, the r-process-rich stars possess constant Hf/La and Hf/Eu abundance ratios, log epsilon (Hf/La) = -0.13 +/- 0.02 (sigma = 0.06) and log epsilon (Hf/Eu) = +0.04 +/- 0.02 (sigma = 0.06). The observed average stellar abundance ratio of Hf/Eu and La/Eu is larger than previous estimates of the solar system r-process-only value, suggesting a somewhat larger contribution from the r-process to the production of Hf and La. The newly determined Hf values could be employed as part of the chronometer pair, Th/Hf, to determine radioactive stellar ages.

J. E. Lawler; E. A. Den Hartog; Z. E. Labby; C. Sneden; J. J. Cowan; I. I. Ivans

2006-11-01

307

Posterior thigh perforator flaps: an anatomical study to localize and classify posterior thigh perforators.  

PubMed

In the last decade perforator flaps have been used increasingly for different indications. Many regions may serve as donor site. In this respect the posterior thigh region (PTR) has been neglected as a potential donor site for many years. The purpose of this study was to provide complete mapping of perforators supplying the posterior thigh region. Twelve fresh cadaver thighs were prepared injecting diluted acrylic paint into the iliac artery. Thereafter the posterior thighs were dissected from medial to lateral, distinguishing the perforators at the level of the superficial fascia. The perforators were localized and origin, source, length and diameter of the perforators were documented. Analysis occurred using ANOVA and the two proportion Z test. The distribution of musculocutaneous and septocutaneous perforators was respectively 69.1% and 30.9% (P = 0.002). The PTR was divided in thirds. Most perforators (53.2%) were found in de middle third of the PTR. The deep femoral artery (DFA) was the main origin of perforators (61.7%), followed by the superficial femoral artery (SFA) (27.7%) and the popliteal artery (PA) (10.6%). The DFA perforators were the longest with a mean length of 13.7 ± 4,69 cm, the SFA perforators were 9.79 ± 3.76 cm and the PA perforators were 8.6 ± 3.37 cm. The PTR offers a sufficient number of suitable perforators to serve as an adequate donorsite for pedicled and free flaps. PMID:23716194

Hupkens, Pieter; Ozturk, Ekin; Wittens, Sabine; Hoevenaren, Ingrid A; Kooloos, Jan G M; Ulrich, Dietmar J O

2013-07-01

308

Primer on Probability  

NSDL National Science Digital Library

How did Gregor Mendel derive the Law of Segregation and the Law of Independent Assortment? Most budding geneticists know he used peas, but how exactly did he do it? This fine document from Professor Robert Merritt of Smith College provides explanations of Mendel's groundbreaking work, along with information on the basic rules of probability. The 20-page document was developed for "Your Genes, Your Chromosomes," a course that was offered through the Smith College Summer Science and Engineering Program. The document explains how to test a hypothesis using The Chi-Square Test, and also covers topics such as sex determination and sex linkage, blood group, and gene interaction. Finally, the document contains a detailed explanation of the basic rules of probability and a selection of sample problems.

Merritt, Robert

309

Bayesian Probability Theory  

NASA Astrophysics Data System (ADS)

Preface; Part I. Introduction: 1. The meaning of probability; 2. Basic definitions; 3. Bayesian inference; 4. Combinatrics; 5. Random walks; 6. Limit theorems; 7. Continuous distributions; 8. The central limit theorem; 9. Poisson processes and waiting times; Part II. Assigning Probabilities: 10. Transformation invariance; 11. Maximum entropy; 12. Qualified maximum entropy; 13. Global smoothness; Part III. Parameter Estimation: 14. Bayesian parameter estimation; 15. Frequentist parameter estimation; 16. The Cramer–Rao inequality; Part IV. Testing Hypotheses: 17. The Bayesian way; 18. The frequentist way; 19. Sampling distributions; 20. Bayesian vs frequentist hypothesis tests; Part V. Real World Applications: 21. Regression; 22. Inconsistent data; 23. Unrecognized signal contributions; 24. Change point problems; 25. Function estimation; 26. Integral equations; 27. Model selection; 28. Bayesian experimental design; Part VI. Probabilistic Numerical Techniques: 29. Numerical integration; 30. Monte Carlo methods; 31. Nested sampling; Appendixes; References; Index.

von der Linden, Wolfgang; Dose, Volker; von Toussaint, Udo

2014-06-01

310

Low probability of intercept  

Microsoft Academic Search

LOW Probability of Intercept (LPI) analysis shows the effect of scenario-dependent parameters and detectability-threshold factors in jamming and nonjamming environments. The most significant improvement in LPI performance may be obtained by operating at Extremely High Frequency (EHF) and by maximizing the effective spread-spectrum processing gain and the communicator’s antenna discrimination to the jamming signal, and by minimizing the number of

A. B. GLENN

1983-01-01

311

Probability in Quantum Mechanics  

Microsoft Academic Search

The concept of probability played an important role in the very beginning of ? quantum theory, when Max Planck (1858–1947)\\u000a postulated the discrete emission and absorption of radiation in a ? black body radiation. The quantum statistical mechanics\\u000a developed by Planck and his successors has extraordinary consequences treated elsewhere in this Compendium. Here, however,\\u000a the emphasis will be upon the

Abner Shimony

312

Important Probability Distributions  

E-print Network

probability mass function (or pdf). If X B(n, p) then E(X) = np V (X) = np(1 - p) X = np(1 - p functions. Illustration 1. A Binomial random variable is the sum of n inde- pendent Bernoulli random (pet )x (1 - p)1-x = pet + (1 - p). Now, let Y Binom(n, p). Then My(t) = E(ety ) = n x=0 ety n y py (1

Behseta, Sam

313

Computational and Inferential Difficulties with Mixture Posterior Distributions  

Microsoft Academic Search

This article deals with both exploration and interpretation problems related to posterior distributions for mixture models. The specification of mixture posterior distributions means that the presence of k! modes is known immediately. Standard Markov chain Monte Carlo (MCMC) techniques usually have difficulties with well-separated modes such as occur here; the MCMC sampler stays within a neighborhood of a local mode

Gilles Celeux; Merrilee Hurn; Christian P. Robert

2000-01-01

314

Picture Agnosia as a Characteristic of Posterior Cortical Atrophy  

Microsoft Academic Search

Background: Posterior cortical atrophy (PCA) is a degenerative disease characterized by progressive visual agnosia with posterior cerebral atrophy. We examine the role of the picture naming test and make a number of suggestions with regard to diagnosing PCA as atypical dementia. Methods: We investigated 3 cases of early-stage PCA with 7 control cases of Alzheimer disease (AD). The patients and

Azusa Sugimoto; Akira Midorikawa; Shinichi Koyama; Akinori Futamura; Sotaro Hieda; Mitsuru Kawamura

2012-01-01

315

Assessing the Calibration of Naive Bayes' Posterior Paul N. Bennett  

E-print Network

Assessing the Calibration of Naive Bayes' Posterior Estimates Paul N. Bennett September 12, 2000 In this paper, we give evidence that the posterior distribution of Naive Bayes goes to zero or one exponen likelihood scheme, and the results are evaluated. Email: pbennett+@cs.cmu.edu #12; Keywords: Naive Bayes

316

Acute Posterior Tarsal Tunnel Syndrome Caused by Gouty Tophus.  

PubMed

Gouty tophus of the tarsal tunnel is a rare cause of posterior tarsal tunnel syndrome. We present a case of acute posterior tarsal tunnel syndrome due to gouty tophus that required early tarsal tunnel release in order to avoid irreversible nerve damage. The presence of background neuropathy resulted in a less favorable result than expected. PMID:25205680

Lui, Tun Hing

2014-09-01

317

Investigation of occiput posterior delivery by intrapartum sonography  

Microsoft Academic Search

Objective To investigate if occiput posterior delivery is the consequence of persistence of an initial occiput posterior position or malrotation from an initial occiput anterior or transverse position. Methods This was a cross-sectional study involving transabdominal sonography to determine fetal occipital position in 918 singleton pregnancies with cephalic presentation in active labor at 37-42 weeks of gestation. The relationship between

S. Akmal; E. Tsoi; R. Howard; E. Osei; K. H. Nicolaides

2004-01-01

318

A Case of Angiomyolipoma of the Posterior Upper Mediastinum  

Microsoft Academic Search

Angiomyolipoma (AML) is uncommon outside the kidney, and it rarely occurs in mediastinum. This article presents a case of posterior upper mediastinal AML with a review of the literature on angiomyolipoma. A 56-year-old woman was referred to our hospital with 8-month history of cough and chest pain. Radiology showed a mass in the posterior upper mediastinum. Left thoracotomy was done

Shirin Karimi; Moslem Bahadori; Foroozan Mohammadi; Abbas Mir-Afsharieh; Saviz Pejhan; Soheila Zahirifard

319

Postural stability and unilateral posterior crossbite: Is there a relationship?  

Microsoft Academic Search

The aim of this study was to test the hypothesis that unilateral posterior crossbite influences postural stability of the whole body. Twenty-six subjects (14 males and 12 females) affected with unilateral posterior crossbite were selected and compared with 52 controls matched for age and gender. Postural stability was assessed using a stabilometric platform. The following stabilometric measurements were assessed: weight

Ambrosina Michelotti; Gerarda Buonocore; Mauro Farella; Gioacchino Pellegrino; Carlo Piergentili; Stefano Altobelli; Roberto Martina

2006-01-01

320

Paratrooper's Ankle Fracture: Posterior Malleolar Fracture  

PubMed Central

Background We assessed the frequency and types of ankle fractures that frequently occur during parachute landings of special operation unit personnel and analyzed the causes. Methods Fifty-six members of the special force brigade of the military who had sustained ankle fractures during parachute landings between January 2005 and April 2010 were retrospectively analyzed. The injury sites and fracture sites were identified and the fracture types were categorized by the Lauge-Hansen and Weber classifications. Follow-up surveys were performed with respect to the American Orthopedic Foot and Ankle Society ankle-hindfoot score, patient satisfaction, and return to preinjury activity. Results The patients were all males with a mean age of 23.6 years. There were 28 right and 28 left ankle fractures. Twenty-two patients had simple fractures and 34 patients had comminuted fractures. The average number of injury and fractures sites per person was 2.07 (116 injuries including a syndesmosis injury and a deltoid injury) and 1.75 (98 fracture sites), respectively. Twenty-three cases (41.07%) were accompanied by posterior malleolar fractures. Fifty-five patients underwent surgery; of these, 30 had plate internal fixations. Weber type A, B, and C fractures were found in 4, 38, and 14 cases, respectively. Based on the Lauge-Hansen classification, supination-external rotation injuries were found in 20 cases, supination-adduction injuries in 22 cases, pronation-external rotation injuries in 11 cases, tibiofibular fractures in 2 cases, and simple medial malleolar fractures in 2 cases. The mean follow-up period was 23.8 months, and the average follow-up American Orthopedic Foot and Ankle Society ankle-hindfoot score was 85.42. Forty-five patients (80.36%) reported excellent or good satisfaction with the outcome. Conclusions Posterior malleolar fractures occurred in 41.07% of ankle fractures sustained in parachute landings. Because most of the ankle fractures in parachute injuries were compound fractures, most cases had to undergo surgical repairs. PMID:25729514

Young, Ki Won; Cho, Jae Ho; Kim, Hyung Seuk; Cho, Hun Ki; Lee, Kyung Tai

2015-01-01

321

Approximation of Failure Probability Using Conditional Sampling  

NASA Technical Reports Server (NTRS)

In analyzing systems which depend on uncertain parameters, one technique is to partition the uncertain parameter domain into a failure set and its complement, and judge the quality of the system by estimating the probability of failure. If this is done by a sampling technique such as Monte Carlo and the probability of failure is small, accurate approximation can require so many sample points that the computational expense is prohibitive. Previous work of the authors has shown how to bound the failure event by sets of such simple geometry that their probabilities can be calculated analytically. In this paper, it is shown how to make use of these failure bounding sets and conditional sampling within them to substantially reduce the computational burden of approximating failure probability. It is also shown how the use of these sampling techniques improves the confidence intervals for the failure probability estimate for a given number of sample points and how they reduce the number of sample point analyses needed to achieve a given level of confidence.

Giesy. Daniel P.; Crespo, Luis G.; Kenney, Sean P.

2008-01-01

322

Isolated posterior capsular rupture following blunt head trauma  

PubMed Central

Closed-globe traumatic cataract is not uncommon in males in the pediatric age group. However, there is a relative paucity of literature on isolated posterior lens capsule rupture associated with closed-globe traumatic cataract. We report a case of a 6-year-old boy who presented with white cataract 1 day after blunt trauma to the forehead associated with posterior capsular rupture that was detected by B-scan ultrasonography preoperatively. No stigmata of trauma outside the posterior capsule could be detected by slit-lamp exam, funduscopy, and optical coherence tomography. Phacoemulsification with posterior chamber intraocular lens implant was performed 24 hours after trauma, with the patient achieving 6/6 visual acuity 1 week and 6 months after surgery. Our case is unique, being the youngest (amblyogenic age) to be reported, with prompt surgical intervention, and with no signs of trauma outside the posterior capsule. PMID:25506201

Mansour, Ahmad M; Jaroudi, Mahmoud O; Hamam, Rola N; Maalouf, Fadi C

2014-01-01

323

Direct probability mapping of contaminants  

SciTech Connect

Exhaustive characterization of a contaminated site is a physical and practical impossibility. Descriptions of the nature, extent, and level of contamination, as well as decisions regarding proposed remediation activities, must be made in a state of uncertainty based upon limited physical sampling. Geostatistical simulation provides powerful tools for investigating contaminant levels, and in particular, for identifying and using the spatial interrelationships among a set of isolated sample values. This additional information can be used to assess the likelihood of encountering contamination at unsampled locations and to evaluate the risk associated with decisions to remediate or not to remediate specific regions within a site. Past operation of the DOE Feed Materials Production Center has contaminated a site near Fernald, Ohio, with natural uranium. Soil geochemical data have been collected as part of the Uranium-in-Soils Integrated Demonstration Project. These data have been used to construct a number of stochastic images of potential contamination for parcels approximately the size of a selective remediation unit. Each such image accurately reflects the actual measured sample values, and reproduces the univariate statistics and spatial character of the extant data. Post-processing of a large number of these equally likely, statistically similar images produces maps directly showing the probability of exceeding specified levels of contamination. Evaluation of the geostatistical simulations can yield maps representing the expected magnitude of the contamination for various regions and other information that may be important in determining a suitable remediation process or in sizing equipment to accomplish the restoration.

Rautman, C.A.

1993-09-17

324

Neglected posterior dislocation of the elbow.  

PubMed

The study included two adults and four children who underwent open reduction for subacute, untreated posterior dislocation of the elbow. Elbow stiffness was the main indication for surgery, and in all cases elbow movement was inadequate for the activities of daily living. Mean time from injury was 2 months and mean follow-up was 19 months. At final follow-up there were no cases of instability; according to the Mayo Elbow Performance Index(14), four outcomes were excellent, one good and one poor; the mean score improved from five preoperatively to 83 postoperatively, mean elbow flexion from 18 degrees to 93 degrees and mean pronation-supination from 20 degrees to 119 degrees. Complications included pin site infections in one case, treated by oral antibiotics and dressings, and severe degenerative changes with myositis ossificans in one case. Open reduction and V-Y muscleplasty followed by a supervised physical therapy programme can restore elbow function and stability in neglected elbow dislocations presenting up to 3 months after injury. PMID:19237154

Elzohairy, Mohamed Mansour

2009-02-01

325

Posterior reversible leukoencephalopathy syndrome associated with pazopanib.  

PubMed

A 62-year-old female patient with metastatic renal cell carcinoma under third-line treatment with pazopanib for 8 weeks suddenly developed severe headaches, grand mal seizures and paresis of the left arm in combination with gait instability as well as nausea and vomiting during her vacation abroad. The emergency physician measured systolic blood pressure values over 300 mm Hg and suspected a stroke. The CT imaging without contrast agent in a local hospital did not show any pathologic findings despite bone metastases. The colleagues suspected cerebral metastases or meningeosis carcinomatosa and referred the patient to our department for further diagnostics and treatment planning. An MRI scan ruled out the suspected cerebral metastases or meningeosis carcinomatosa, but showed signs of reversible posterior leukoencephalopathy syndrome (RPLS) in the form of band-like hyperintensities as a sign of cytotoxic edema in the gray and white matter of the left parietal lobe. The patient then reported that similar blood pressure values had been measured shortly after the start of a first-line therapy with sunitinib, so that we discontinued the current treatment with pazopanib. Within 6 days the neurologic symptoms vanished and the patient was discharged. An intermittent hypertension persisted. A follow-up MRI 3 weeks later showed an RPLS-typical cortical infarction in the affected area. RPLS should be considered as the actual reason for neurologic findings in hypertensive patients with known metastatic cancers under tyrosine kinase inhibitor therapy. PMID:23626562

Foerster, Robert; Welzel, Thomas; Debus, Juergen; Gruellich, Carsten; Jaeger, Dirk; Potthoff, Karin

2013-01-01

326

Automatic quantification of posterior capsule opacification  

NASA Astrophysics Data System (ADS)

After Cataract surgery where a plastic implant lens is implanted into the eye to replace the natural lens, many patients suffer from cell growth across a membrane situated at the back of the lens which degrades their vision. The cell growth is known as Posterior Capsule Opacification (or PCO). It is important to be able to quantify PCO so that the effect of different implant lens types and surgical techniques may be evaluated. Initial results obtained using a neural network to detect PCO from implant lenses are compared to an established but less automated method of detection, which segments the images using texture segmentation in conjunction with co- occurrence matrices. Tests show that the established method performs well in clinical validation and repeatability trials. The requirement to use a neural network to analyze the implant lens images evolved from the analysis of over 1000 images using the established co-occurrence matrix segmentation method. The work shows that a method based on neural networks is a promising tool to automate the procedure of calculating PCO.

Barman, Sarah A.; Uyyanonvara, Bunyarit; Boyce, James F.; Sanguinetti, Giorgia; Hollick, Emma J.; Meacock, William R.; Spalton, David J.; Paplinski, Andrew P.

2000-06-01

327

Posterior mediastinal angioleiomyoma: report of a case.  

PubMed

We describe a case of mediastinal angioleiomyoma in an asymptomatic 72-year-old man, who was admitted to our hospital for a mediastinal tumor discovered during an annual medical examination. The tumor was evaluated by computed tomography (CT) and magnetic resonance imaging (MRI). Unenhanced CT scans demonstrated a tumor that was adjacent to the descending aorta. The tumor was partially enhanced in the early phase of contrast-enhanced CT, and in the late phase there was additional tumor enhancement. With MRI, the tumor displayed a homogeneous low signal intensity on the T1-weighted image and a homogeneous very high signal intensity on the T2-weighted image. Contrast-enhanced MRI demonstrated the same enhancement pattern as CT. The examination results led to a preoperative diagnosis of posterior mediastinal hemangioma, and the patient underwent surgery. The tumor originated from the supreme intercostal vein, and was diagnosed as an angioleiomyoma by histopathologic examination. Because mediastinal angioleiomyomas are very rare, they are difficult to diagnose preoperatively. However, we believe that CT and MRI can be of significant help in the differential diagnosis. PMID:18043396

Yasuda, Akira; Mizuno, Akira; Mishima, Akira; Sasaki, Shigeru; Ochi, Nobuo; Wakasugi, Takehiro; Sawai, Hirozumi; Takeyama, Hiromitsu; Manabe, Tadao

2007-11-01

328

Fire!, Probability, and Chaos  

NSDL National Science Digital Library

This lesson is designed to introduce students to the concept of chaos and how it relates to probability. The lesson briefly delves into the ideas of mean and variance as well. This lesson provides links to discussions and activities related to chaos 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. Note, reading level is not indicated because the lesson does not include student reading material.

2010-01-01

329

Time-Accurate Computational Simulation  

NASA Technical Reports Server (NTRS)

Time accurate CFD may offer a faster approach to S&C aerodynamic database population than the conventional point by point steady state CFD. We would directly simulate -, -sweeps or other configuration movements typically of measurement sequence in wind tunnels. A second objective is to demonstrate potential applications to assessment of S&C dynamic derivatives by simulating vehicle motions such as free to roll, and nonlinearity such as the trends of aerodynamic forces near CL-max or flow hysteresis.

Pao, S. Paul; Buning, Pieter G.

2004-01-01

330

Probability Forecasting Using Monte Carlo Simulation  

NASA Astrophysics Data System (ADS)

Space Situational Awareness (SSA) is defined as the knowledge and characterization of all aspects of space. SSA is now a fundamental and critical component of space operations. Increased dependence on our space assets has in turn lead to a greater need for accurate, near real-time knowledge of all space activities. With the growth of the orbital debris population, satellite operators are performing collision avoidance maneuvers more frequently. Frequent maneuver execution expends fuel and reduces the operational lifetime of the spacecraft. Thus the need for new, more sophisticated collision threat characterization methods must be implemented. The collision probability metric is used operationally to quantify the collision risk. The collision probability is typically calculated days into the future, so that high risk and potential high risk conjunction events are identified early enough to develop an appropriate course of action. As the time horizon to the conjunction event is reduced, the collision probability changes. A significant change in the collision probability will change the satellite mission stakeholder's course of action. So constructing a method for estimating how the collision probability will evolve improves operations by providing satellite operators with a new piece of information, namely an estimate or 'forecast' of how the risk will change as time to the event is reduced. Collision probability forecasting is a predictive process where the future risk of a conjunction event is estimated. The method utilizes a Monte Carlo simulation that produces a likelihood distribution for a given collision threshold. Using known state and state uncertainty information, the simulation generates a set possible trajectories for a given space object pair. Each new trajectory produces a unique event geometry at the time of close approach. Given state uncertainty information for both objects, a collision probability value can be computed for every trail. This yields a collision probability distribution given known, predicted uncertainty. This paper presents the details of the collision probability forecasting method. We examine various conjunction event scenarios and numerically demonstrate the utility of this approach in typical event scenarios. We explore the utility of a probability-based track scenario simulation that models expected tracking data frequency as the tasking levels are increased. The resulting orbital uncertainty is subsequently used in the forecasting algorithm.

Duncan, M.; Frisbee, J.; Wysack, J.

2014-09-01

331

Posterior quadrant disconnection for refractory epilepsy: A case series  

PubMed Central

Objective: To analyze the surgical outcome and safety of posterior quadrant disconnection in medically refractory epilepsy arising from the posterior head region from a level IV tertiary care center over a period of three years. Materials and Methods: Seven consecutive patients who underwent posterior quadrant disconnection for refractory epilepsy were analyzed. Results: We analyzed the data of seven (n = 7) consecutive posterior quadrant epilepsy patients who underwent posterior quadrant disconnection with a mean age of 8.5 years over the last three years of which 4 were male and 3 females. All patients underwent extensive pre-surgical evaluation including detailed history, examination, prolonged video EEG recordings, neuropsychological testing, MRI brain, DTI, PET scan (n = 6), fMRI (n = 4), WADA test (n = 1) and invasive recording (n = 1), Of seven patients four had left sided pathology and three had right sided pathology. All patients except one underwent pure disconnection and one underwent partial resection. Conclusion: Posterior quadrant disconnection is effective surgical procedure for medically refractory epilepsy arising from the posterior quadrant in carefully selected patients without morbidity or functional disability across various age groups especially in children. In our series, all seven patient had good seizure outcome and none had functional disabilities. PMID:25506159

Nooraine, Javeria; R, Shiva kumar; Iyer, Rajesh B; Rao, Ravi Mohan; Raghavendra, Seetharam

2014-01-01

332

Posterior Urethral Valves; A single Center Experience  

PubMed Central

Objective Posterior urethral valves (PUV) are the most common cause of bladder outlet obstruction in infancy that impair renal and bladder function. This study was planned to evaluate and record the various clinical presentations and management, complications, and surgical management and long-term outcome of PUV. Methods In a retrospective study, 98 patients who have been treated for PUV are evaluated in Mofid Children's Hospital from January 2007 to December 2012. Detailed history taken and paraclinical examinations were performed in each patient and diagnosis was confirmed by voiding-cysto-urethrography (VCUG). PUV had been ablated in 62 patients by electric hook, and diversion was performed in 42 (42.85%) cases. Data were analyzed by SPSS software version18. Findings Totally 98 patients with mean age at diagnosis 62 (±13) days were included in this study. Fifty seven cases had been catheterized within one to 6 days of life (mean age one day), PUV was ablated in 62 patients by electric hook, and diversion was performed in 42 cases. The most common symptom in our group was dribbling poor stream 51% and urinary tract infection (UTI) 40.8%. There was vesico-ureteral-reflux (VUR) in 61.2%, and hydronephrosis in 82.6%. Most common associated anomaly was kidney anomalies (multicystic kidney disease and renal agenesis/dysplasia) in 8 (8.2%) patients. Twenty patients had prenatal diagnosis of PUV. Complication occurred in three (3.1%) patients. Mortality occurred in 5 (5.1%) patients. Mean follow-up period was 3.4±1.2 years (1.5 months to 5 years). Conclusion Urinary drainage by feeding tube in early days of infancy, followed by valve ablation is the best treatment in PUV, and urinary diversion improves the outcome. VCUG is still the gold-standard imaging modality for documenting PUVs. The factors like renal dysplasia and UTI have their role in final outcome. PMID:24800012

Mirshemirani, Alireza; Khaleghnejad, Ahmad; Rouzrokh, Mohsen; Sadeghi, Afsaneh; Mohajerzadeh, Leila; Sharifian, Mustafa

2013-01-01

333

[Seven cases of posterior cerebral artery aneurysms].  

PubMed

In a period of ten years, since January 1996, we have encountered seven cases of posterior cerebral artery aneurysms (0.58% of surgically treated 1027 aneurysms in our hospital). Six of these cases were females (from 39 years old to 73 years old, average 54.5 years old). In five of the cases, neck clippings were performed, using the pterional approach for one P1 and one P2a aneurysm, the remaining three were clipping using the subtemporal approach for one P2a and two P2p aneurysms. In one case diagnosed as "unknown SAH" by typical findings of the CT scan and normal four-vessel study at the time of admission. The second vertebral angiography (two weeks later) revealed a P2a aneurysm. Such a case attracted our interest in the clinic, because many similar cases might have been diagnosed as "unknown SAH". In the case of a 42-year-old male with intracerebral hematoma, four-vessel study made a definite diagnosis as moyamoya disease and revealed a P2a aneurysm, which we cured by embolization of GDC for the preservation of anastomosis networks which had already been formed. Intravascular embolization is very effective, but sufficient studies are required before applying it in the cases of large and/or thrombosed aneurysms. We described surgical approaches about pterional, subtemporal and transchoroidal approaches and discussed some of the differences in the classification methods of Pia, Yasargil, Zear & Rhoton and Seoane. In particular, attention is necessary because we have confused Yasargil's classification with Zeal & Rhoton's classifications by using of the same notation, "Pn". PMID:17424966

Gi, Hidefuku; Uno, Jyunji; Ikai, Yoshiaki; Inoha, Satoshi; Koga, Hiromichi; Yamaguchi, Shinya; Nagaoka, Shintaro

2007-04-01

334

Posterior communicating artery aneurysm rupture mimicking apoplexy  

PubMed Central

Background: Cerebral aneurysm rupture can lead to devastating neurological complications and present a complex problem to treat. We report a unique case of a ruptured posterior communicating artery (PCoA) aneurysm presenting with sudden and complete vision loss. Case Description: A 39-year-old man presented with the acute onset of severe headache and complete bilateral vision loss. The patient described headaches for several months prior to presentation. However, prior to the day of presentation, he had no visual disturbance. A CT angiogram (CTA) and magnetic resonance imaging (MRI) of the brain revealed a 1.6-cm, non-contrast enhancing suprasellar mass, eccentric to the left side, consistent with hemorrhagic mass. There was no obvious aneurysm or vascular malformation. The sella tursica was normal in appearance. The patient was taken for an immediate endoscopic endonasal transtuberculum approach for optic nerve decompression. Hematoma without an associated tumor was encountered and partially evacuated before aborting with resultant partial improvement in vision. A subsequent cerebral angiogram revealed an irregularly shaped, postero-laterally pointing, 2.5-mm left PCoA aneurysm. The patient was then taken for open clipping of the ruptured aneurysm. A large, fibrinous capsule was found over the superolateral aspect of the aneurysm. The ruptured aneurysm was secured with clips and the surrounding hematoma was evacuated. Conclusion: In the immediate postoperative period, the patient regained vision in the nasal field of his right eye. This case illustrates a unique presentation of a ruptured PCoA aneurysm, and thus must be considered in the differential diagnosis of a suprasellar hemorrhage resulting in visual loss in absence of a recognizable associated tumor. PMID:22145088

Bonfield, Christopher M.; Gardner, Paul A.

2011-01-01

335

Knowledge Engineering Tools for Probability Elicitation L. R. Hope A. E. Nicholson K. B. Korb  

E-print Network

Knowledge Engineering Tools for Probability Elicitation L. R. Hope A. E. Nicholson K. B. Korb June engineers. This requires domain experts to provide unreasonably accurate probability estimates. To solve node customisation and sliding scale binary elicitation; Verbal Elicitor allows entry of probability

Nicholson, Ann

336

Bayesian Retrieval of Complete Posterior PDFs of Oceanic Rain Rate From Microwave Observations  

NASA Technical Reports Server (NTRS)

This paper presents a new Bayesian algorithm for retrieving surface rain rate from Tropical Rainfall Measurements Mission (TRMM) Microwave Imager (TMI) over the ocean, along with validations against estimates from the TRMM Precipitation Radar (PR). The Bayesian approach offers a rigorous basis for optimally combining multichannel observations with prior knowledge. While other rain rate algorithms have been published that are based at least partly on Bayesian reasoning, this is believed to be the first self-contained algorithm that fully exploits Bayes Theorem to yield not just a single rain rate, but rather a continuous posterior probability distribution of rain rate. To advance our understanding of theoretical benefits of the Bayesian approach, we have conducted sensitivity analyses based on two synthetic datasets for which the true conditional and prior distribution are known. Results demonstrate that even when the prior and conditional likelihoods are specified perfectly, biased retrievals may occur at high rain rates. This bias is not the result of a defect of the Bayesian formalism but rather represents the expected outcome when the physical constraint imposed by the radiometric observations is weak, due to saturation effects. It is also suggested that the choice of the estimators and the prior information are both crucial to the retrieval. In addition, the performance of our Bayesian algorithm is found to be comparable to that of other benchmark algorithms in real-world applications, while having the additional advantage of providing a complete continuous posterior probability distribution of surface rain rate.

Chiu, J. Christine; Petty, Grant W.

2005-01-01

337

Dissociable contributions of the left and right posterior medial orbitofrontal cortex in motivational control of goal-directed behavior.  

PubMed

Several findings from both human neuroimaging and nonhuman primate studies suggest that the posterior medial orbitofrontal cortex (OFC) may be critical for the motivational control of goal-directed behavior. The present study was conducted to clarify the role of the left and right posterior medial OFC in that function by examining the effects of focal unilateral lesions to this region on the performance on an incentive working memory task. The study covered patients who had undergone surgery for an ACoA aneurysm and normal control subjects (C). The patients were subdivided into three groups: those with resection of the left (LGR+) or right (RGR+) posterior part of the gyrus rectus, and without such a resection (GR-). Participants performed a 2-back working memory task under three motivational conditions (penalty, reward, and no-incentive). The C group performed worse in the penalty condition and better in the reward condition as compared to the no-incentive condition. Similar results were obtained for the GR- group. Performance of the LGR+ group did not depend on incentive manipulations, whereas the RGR+ group performed better in both the penalty and reward conditions than in the no-incentive condition. The results show that the posterior medial OFC is involved in the motivational modulation of working memory performance. Our findings also suggest that the left posterior medial OFC plays a crucial role in this function, whereas the right posterior medial OFC is particularly involved in the processing of the punishing aspect of salient events and it probably mediates in guiding behavior on the basis of negative outcomes of action. PMID:21741492

Szatkowska, Iwona; Szyma?ska, Olga; Marchewka, Artur; Soluch, Pawe?; Rymarczyk, Krystyna

2011-09-01

338

Asystole during posterior fossa surgery: Report of two cases  

PubMed Central

Asystole during posterior fossa neurosurgical procedures is not uncommon. Various causes have been implicated, especially when surgical manipulation is carried out in the vicinity of the brain stem. The trigemino-cardiac reflex has been attributed as one of the causes. Here, we report two cases who suffered asystole during the resection of posterior fossa tumors. The vago-glossopharyngeal reflex and the direct stimulation of the brainstem were hypothesized as the causes of asytole. These episodes resolved spontaneously following withdrawal of the surgical stimulus emphasizing the importance of anticipation and vigilance during critical moments of tumor dissection during posterior fossa surgery. PMID:22870159

Goyal, Keshav; Philip, Frenny Ann; Rath, Girija Prasad; Mahajan, Charu; Sujatha, M.; Bharti, Sachidanand Jee; Gupta, Nidhi

2012-01-01

339

Posterior corneal aberrations and their compensation effects on anterior corneal aberrations in keratoconic eyes  

E-print Network

Posterior corneal aberrations and their compensation effects on anterior corneal aberrations;PURPOSE To characterize posterior corneal aberrations in keratoconic (KC) eyes and investigate compensatory effects between anterior and posterior corneal surfaces. METHODS The corneal topography of a total

Yoon, Geunyoung

340

Scalable and Robust Bayesian Inference via the Median Posterior Stanislav Minsker1  

E-print Network

Scalable and Robust Bayesian Inference via the Median Posterior Stanislav Minsker1 SMINSKER into several non-overlapping subgroups, evaluating the posterior distribution given each independent subgroup (MCMC) - one of the key techniques for approximating the posterior distribution of parameters

Minsker, Stanislav

341

Journal of Multivariate Analysis 74, 49 68 (2000) Asymptotic Normality of Posterior Distributions for  

E-print Network

Journal of Multivariate Analysis 74, 49 68 (2000) Asymptotic Normality of Posterior Distributions 12, 1997 We study consistency and asymptotic normality of posterior distributions of the natural certain growth restrictions on the dimension, we show that the posterior distributions concentrate

Ghoshal, Subhashis

342

21 CFR 872.3900 - Posterior artificial tooth with a metal insert.  

Code of Federal Regulations, 2013 CFR

...false Posterior artificial tooth with a metal insert. 872.3900 Section 872...3900 Posterior artificial tooth with a metal insert. (a) Identification. A posterior artificial tooth with a metal insert is a porcelain device with...

2013-04-01

343

21 CFR 872.3900 - Posterior artificial tooth with a metal insert.  

Code of Federal Regulations, 2012 CFR

...false Posterior artificial tooth with a metal insert. 872.3900 Section 872...3900 Posterior artificial tooth with a metal insert. (a) Identification. A posterior artificial tooth with a metal insert is a porcelain device with...

2012-04-01

344

21 CFR 872.3900 - Posterior artificial tooth with a metal insert.  

Code of Federal Regulations, 2011 CFR

...false Posterior artificial tooth with a metal insert. 872.3900 Section 872...3900 Posterior artificial tooth with a metal insert. (a) Identification. A posterior artificial tooth with a metal insert is a porcelain device with...

2011-04-01

345

Posterior concentration rates for empirical Bayes procedures, with applications to Dirichlet Process mixtures  

E-print Network

Posterior concentration rates for empirical Bayes procedures, with applications to Dirichlet posterior concentration rates for data-dependent priors (or empirical Bayes approaches). We aim at providing multiplicative intensity with priors not depending on the data. Keywords: Empirical Bayes, posterior

Paris-Sud XI, Université de

346

21 CFR 872.3900 - Posterior artificial tooth with a metal insert.  

Code of Federal Regulations, 2010 CFR

...false Posterior artificial tooth with a metal insert. 872.3900 Section 872...3900 Posterior artificial tooth with a metal insert. (a) Identification. A posterior artificial tooth with a metal insert is a porcelain device with...

2010-04-01

347

Fast and accurate database searches with MS-GF+Percolator  

SciTech Connect

To identify peptides and proteins from the large number of fragmentation spectra in mass spectrometrybased proteomics, researches commonly employ so called database search engines. Additionally, postprocessors like Percolator have been used on the results from such search engines, to assess confidence, infer peptides and generally increase the number of identifications. A recent search engine, MS-GF+, has previously been showed to out-perform these classical search engines in terms of the number of identified spectra. However, MS-GF+ generates only limited statistical estimates of the results, hence hampering the biological interpretation. Here, we enabled Percolator-processing for MS-GF+ output, and observed an increased number of identified peptides for a wide variety of datasets. In addition, Percolator directly reports false discovery rate estimates, such as q values and posterior error probabilities, as well as p values, for peptide-spectrum matches, peptides and proteins, functions useful for the whole proteomics community.

Granholm, Viktor; Kim, Sangtae; Navarro, Jose' C.; Sjolund, Erik; Smith, Richard D.; Kall, Lukas

2014-02-28

348

Probabilities for Solar Siblings  

NASA Astrophysics Data System (ADS)

We have shown previously (Bobylev et al. Astron Lett 37:550-562, 2011) that some of the stars in the solar neighborhood today may have originated in the same star cluster as the Sun, and could thus be called Solar Siblings. In this work we investigate the sensitivity of this result to galactic models and to parameters of these models, and also extend the sample of orbits. There are a number of good candidates for the sibling category, but due to the long period of orbit evolution since the break-up of the birth cluster of the Sun, one can only attach probabilities of membership. We find that up to 10 % (but more likely around 1 %) of the members of the Sun's birth cluster could be still found within 100 pc from the Sun today.

Valtonen, Mauri; Bajkova, A. T.; Bobylev, V. V.; Mylläri, A.

2015-02-01

349

Probabilities for Solar Siblings  

E-print Network

We have shown previously (Bobylev et al 2011) that some of the stars in the Solar neighborhood today may have originated in the same star cluster as the Sun, and could thus be called Solar Siblings. In this work we investigate the sensitivity of this result to Galactic models and to parameters of these models, and also extend the sample of orbits. There are a number of good candidates for the Sibling category, but due to the long period of orbit evolution since the break-up of the birth cluster of the Sun, one can only attach probabilities of membership. We find that up to 10% (but more likely around 1 %) of the members of the Sun's birth cluster could be still found within 100 pc from the Sun today.

Valtonen, M; Bobylev, V V; Myllari, A

2015-01-01

350

Accurate vacuum-polarization calculations  

NASA Astrophysics Data System (ADS)

A numerical scheme for evaluating the part of the one-photon vacuum-polarization effect not accounted for by the Uehling potential (the Wichmann-Kroll effect) is presented. The method can be used with an arbitary atomic model potential describing the bound electrons. Benchmark results for this effect are presented for hydrogenlike levels using a uniform nuclear-charge distribution. The effect of direct and exchange electron screening on the vacuum polarization are discussed in connection with the accurately measured 2p1/2-2s1/2 transition in lithiumlike uranium.

Persson, Hans; Lindgren, Ingvar; Salomonson, Sten; Sunnergren, Per

1993-10-01

351

Efficient and accurate fragmentation methods.  

PubMed

Conspectus Three novel fragmentation methods that are available in the electronic structure program GAMESS (general atomic and molecular electronic structure system) are discussed in this Account. The fragment molecular orbital (FMO) method can be combined with any electronic structure method to perform accurate calculations on large molecular species with no reliance on capping atoms or empirical parameters. The FMO method is highly scalable and can take advantage of massively parallel computer systems. For example, the method has been shown to scale nearly linearly on up to 131?000 processor cores for calculations on large water clusters. There have been many applications of the FMO method to large molecular clusters, to biomolecules (e.g., proteins), and to materials that are used as heterogeneous catalysts. The effective fragment potential (EFP) method is a model potential approach that is fully derived from first principles and has no empirically fitted parameters. Consequently, an EFP can be generated for any molecule by a simple preparatory GAMESS calculation. The EFP method provides accurate descriptions of all types of intermolecular interactions, including Coulombic interactions, polarization/induction, exchange repulsion, dispersion, and charge transfer. The EFP method has been applied successfully to the study of liquid water, ?-stacking in substituted benzenes and in DNA base pairs, solvent effects on positive and negative ions, electronic spectra and dynamics, non-adiabatic phenomena in electronic excited states, and nonlinear excited state properties. The effective fragment molecular orbital (EFMO) method is a merger of the FMO and EFP methods, in which interfragment interactions are described by the EFP potential, rather than the less accurate electrostatic potential. The use of EFP in this manner facilitates the use of a smaller value for the distance cut-off (Rcut). Rcut determines the distance at which EFP interactions replace fully quantum mechanical calculations on fragment-fragment (dimer) interactions. The EFMO method is both more accurate and more computationally efficient than the most commonly used FMO implementation (FMO2), in which all dimers are explicitly included in the calculation. While the FMO2 method itself does not incorporate three-body interactions, such interactions are included in the EFMO method via the EFP self-consistent induction term. Several applications (ranging from clusters to proteins) of the three methods are discussed to demonstrate their efficacy. The EFMO method will be especially exciting once the analytic gradients have been completed, because this will allow geometry optimizations, the prediction of vibrational spectra, reaction path following, and molecular dynamics simulations using the method. PMID:24810424

Pruitt, Spencer R; Bertoni, Colleen; Brorsen, Kurt R; Gordon, Mark S

2014-09-16

352

Mandibular fracture patterns consistent with posterior maxillary fractures involving the posterior maxillary sinus, pterygoid plate or both: CT characteristics  

PubMed Central

Objectives: The aim of this study was to determine the incidence of posterior maxillary fractures involving the posterior maxillary sinus wall, pterygoid plate or both, unrelated to major midface fractures in patients with mandibular fractures, and to characterize associated fractures. Methods: A CT study was performed in patients with mandibular fractures to identify posterior maxillary fractures. Patients aged under 16 years, those with mandibular fractures involving only dentoalveolar components and those with concurrent major midfacial fractures were excluded. Results: 13 (6.7%) of 194 patients with mandibular fractures also had posterior maxillary fractures (case group). The injury pattern correlated with the external force directed to the lateral side of the mandible (p?posterior mandible occurred with significant frequency (p?=?0.001) when the posterior maxillary fractures involved only the sinus. Conclusions: Mandibular fractures accompanied by posterior maxillary fractures are not rare. The finding of a unilateral posterior maxillary fracture on CT may aid the efficient radiological examination of the mandible based on possible patterns of associated fractures, as follows: in the ipsilateral posterior region as a direct fracture when the impact is a medially directed force, and in the symphysis/parasymphysis or contralateral condylar neck as an indirect fracture. PMID:24336313

Sukegawa, S; Kanno, T; Fujita, G; Yamamoto, N; Furuki, Y; Michizawa, M

2014-01-01

353

Posterior corneal curvature changes after myopic laser in situ keratomileusis  

Microsoft Academic Search

ObjectiveTo assess the posterior corneal power and asphericity changes after myopic laser in situ keratomileusis (LASIK) and to correlate these changes with the amount of correction and the residual stromal bed thickness.

Berthold Seitz; Francia Torres; Achim Langenbucher; Ashley Behrens; Enrique Suárez

2001-01-01

354

Alzheimer's disease in a patient with posterior cortical atrophy  

Microsoft Academic Search

Posterior cortical atrophy (PCA) is characterised by slowly progressive dementia with cognitive and perceptual deficits suggestive of bilateral parieto-occipital disease. A case is reported of a patient with PCA and neuropathological findings consistent with Alzheimer's disease.

M L Berthier; R Leiguarda; S E Starkstein; G Sevlever; A L Taratuto

1991-01-01

355

Traumatic posterior atlantoaxial dislocation without associated fracture and neurological deficit.  

PubMed

Traumatic posterior atlantoaxial dislocation without related fractures of the odontoid process and anterior arch of the atlas is exceedingly rare, with only ten published cases reported so far in English literature. We report on a 44-year-old man with post-traumatic posterior displacement of the atlas with respect to the axis without any associated fractures and neurological deficit caused by a crush injury in earthquake. Radiographs, computed tomography and magnetic resonance imaging revealed posterior displacement of the atlas with the odontoid peg lying anterior and to the right of the anterior arch of the atlas. Partial odontoidectomy and posterior fixation with bone graft were performed in one-stage procedure after several unsuccessful attempts of closed reduction. The patient did not have neurological deterioration after operation. PMID:21207046

Zhen, Ping; Lan, Xu; Yang, Li-Wei

2011-05-01

356

Simplified technique to remove posteriorly dislocated lens implants.  

PubMed

Visual loss caused by posterior dislocation of an intraocular lens (IOL) may be managed by placement of a secondary IOL without removal of the dislocated IOL. However, the improved visual acuity may lead to visual disturbances from the mobile, dislocated IOL. Removal of dislocated implants through the pars plana entails risks of a large pars plana incision to include hemorrhage, hypotony, and a greater potential for vitreous traction caused by extraction across the vitreous base. Removal via the corneal limbus lessens these risks but is made more difficult in the presence of a coexisting posterior chamber IOL. The technique reported allows a controlled conversion from posterior to anterior segment surgical techniques that may aid in either the removal or repositioning of posteriorly dislocated lens implants. PMID:11176991

Wong, K L; Grabow, H B

2001-02-01

357

Vertebrate nervous system posteriorization: Grading the function of Wnt signaling.  

PubMed

The establishment of anteroposterior identity in the vertebrate neural plate has been a subject of investigation for decades, but molecular explanations of posteriorization were only revealed beginning in the late 1980s. A model has emerged from several key studies that identifies Wnt signaling as a key posteriorizing agent, which evidence suggests specifies anteroposterior fates in a concentration-dependent manner. In this review, we consider the historical context of posteriorization studies and evaluate models for Wnt-dependent posteriorization. With new information about the mode of delivery of many signaling ligands, we propose alternative scenarios to reconcile the Wnt gradient model with the complex process of gastrulation and potential non-secretory mechanisms of Wnt delivery. Developmental Dynamics 244:507-512, 2015. © 2014 Wiley Periodicals, Inc. PMID:25410702

Green, David; Whitener, Amy E; Mohanty, Saurav; Lekven, Arne C

2015-03-01

358

A Tale of Two Probabilities  

ERIC Educational Resources Information Center

Two contestants debate the notorious probability problem of the sex of the second child. The conclusions boil down to explication of the underlying scenarios and assumptions. Basic principles of probability theory are highlighted.

Falk, Ruma; Kendig, Keith

2013-01-01

359

Anatomical and functional outcomes in contusion injuries of posterior segment  

Microsoft Academic Search

PurposeTo evaluate the clinical features, and anatomical and visual outcomes in patients with closed-globe contusion injury involving the posterior segment.MethodsRetrospective review of posterior segment contusion injuries admitted to our tertiary referral center.ResultsIn all, 115 patients (115 eyes) with complete data were reviewed. Surgery had been performed in 79 (69%) patients. The mean follow-up period was 6 months (range, 2–34 months).

F Cuneyt Erdurman; G Sobaci; C H Acikel; M O Ceylan; A H Durukan; V Hurmeric

2011-01-01

360

Traumatic posterior atlantoaxial dislocation without associated fracture and neurological deficit  

Microsoft Academic Search

Traumatic posterior atlantoaxial dislocation without related fractures of the odontoid process and anterior arch of the atlas\\u000a is exceedingly rare, with only ten published cases reported so far in English literature. We report on a 44-year-old man with\\u000a post-traumatic posterior displacement of the atlas with respect to the axis without any associated fractures and neurological\\u000a deficit caused by a crush

Ping ZhenXu; Xu Lan; Li-Wei Yang

2011-01-01

361

Oculomotor nerve palsy secondary to aberrant posterior cerebral artery.  

PubMed

The authors report a rare case of an oculomotor nerve palsy attributed to mass effect from an aberrant posterior cerebral artery. The patient presented with complete ptosis, mydriasis and ophthalmoplegia of the affected eye. MRI demonstrated distortion of the oculomotor nerve as it traversed inferior to the non-aneurysmal P1 segment of an aberrant posterior cerebral artery. The oculomotor nerve palsy resolved spontaneously. PMID:24980999

Tan, Terence; Tee, Jin Wee; Wang, Yi Yuen

2014-01-01

362

Diode laser treatment of posterior retinopathy of prematurity  

Microsoft Academic Search

AIMSTo study the efficacy of infrared diode laser for the treatment of posterior retinopathy of prematurity (ROP).METHODS48 eyes of 25 premature babies (mean birth weight 779 (SD 127.7) g; mean gestational age 25.5 (SD 1.47) weeks) with threshold ROP in zone I and posterior zone II were treated by the indirect infrared (810 nm) diode laser. Confluent burns were applied

Ruth Axer-Siegel; Moshe Snir; Dan Cotlear; Ayala Maayan; Ronit Frilling; Irit Rosenbaltt; Dov Weinberger; Israel Kremer; Lea Sirota

2000-01-01

363

Posterior reversible encephalopathy syndrome (PRES) complicating the ‘legal high’ mephedrone  

PubMed Central

The authors report a 19-year-old woman who developed convulsions preceded by nasal ingestion of a cocaine mimic named ‘the bubble’ or mephedrone, obtained legally from a ‘headshop’ in Dublin. Characteristic posterior white matter oedema on brain imaging after the seizure suggested a diagnosis of posterior reversible encephalopathy syndrome (PRES). While PRES has been rarely associated with cocaine ingestion, this is the first report of an association with mephedrone. PMID:22689272

Omer, Taha Adam; Doherty, Colin

2011-01-01

364

Outcome of endoscopic fulguration of posterior urethral valves in children.  

PubMed

Posterior urethral valves are the most common cause of congenital obstructive uropathy leading to renal failure in childhood. This study was undertaken to assess the outcome of endoscopic fulguration of posterior urethral valves based upon the clinical, radiological and laboratory findings. This prospective study was carried out on 50 male children with posterior urethral valves who were treated by endoscopic fulguration and came for routine follow-up. Diagnosis of posterior urethral valves (PUV) was confirmed by voiding cystourethrogram (VCUG). After valve ablation, urine R/M/E, urine for culture and sensitivity test, serum creatinine level, USG of KUB including PVR were done in all cases at 1,3,6,12 months and then at six months interval maximum up to 3 years. Mean age of the patients was 2 years ranging from 1 to 12 years old. Mean follow-up period was 30.48 months after valve ablation. At diagnosis mean serum creatinine +/-SD was 90.4+/-44.8 mumol/lit and it decreased to 56.3+/-11.1micromol/lit at the end of 3-years follow-up. Hydronephrotic changes decreased from 84% to 4%. Proteinuria decreased from 38% to 6% and urinary tract infections decreased from 58% to 4% at the end of final follow up. Although the techniques for posterior urethral valves ablation have been refined and the short-term management of patients with posterior urethral valves has improved remarkably, there is growing concern about the long-term outcome. At present endoscopic fulguration with observation is the treatment of choice for posterior urethral valves. In this study patients improved dramatically following fulguration of posterior urethral valves. Early diagnosis and appropriate therapy may arrest progressive damage and facilitate recovery. Further follow-up studies of longer duration are needed. PMID:19623154

Gupta, S D; Khatun, A A; Islam, A I; Shameem, I A

2009-07-01

365

Influence of persistent occiput posterior position on delivery outcome  

Microsoft Academic Search

OBJECTIVE:To evaluate the influence of intrapartum persistent occiput posterior position of the fetal head on delivery outcome and anal sphincter injury, with reference to the association with epidural analgesia.METHODS:We conducted a prospective observational study of 246 women with persistent occiput posterior position in labor during a 2-year period, compared with 13,543 contemporaneous vaginal deliveries with occiput anterior position.RESULTS:The incidence of

Myra Fitzpatrick; Kathryn McQuillan; Colm O’Herlihy

2001-01-01

366

Posterior reversible encephalopathy syndrome in children with kidney diseases  

Microsoft Academic Search

Posterior reversible encephalopathy syndrome (PRES) was originally used to describe a reversible, predominantly posterior\\u000a leukoencephalopathy in patients who had renal insufficiency, hypertension, or who received immunosuppressive therapy. Since\\u000a PRES is prevalent in children with kidney diseases, awareness and understanding of it is important for practicing pediatric\\u000a nephrologists. A comprehensive approach to the diagnosis of PRES includes thorough determination of predisposing

Kenji Ishikura; Yuko Hamasaki; Tomoyuki Sakai; Hiroshi Hataya; Robert H. Mak; Masataka Honda

367

Experimental Probability in Elementary School  

ERIC Educational Resources Information Center

Probability is more increasingly recognized as a priority in elementary school. In this article, the author argues that if students have a strong understanding of experimental probability, notions of theoretical probability will be easier for the student to understand. In particular, students need extensive experience with experiments using…

Andrew, Lane

2006-01-01

368

HUMAN JUDGMENT AND IMPRECISE PROBABILITIES  

Microsoft Academic Search

IntroductionThe study of human judgment under uncertainty has a history that is almostcontemporaneous with that of probability theories. This is not a coincidence. Fromthe outset, the idea of using probability to describe cognitive states or aspectsof subjective judgment has provoked debate, theory construction, and empiricalresearch. It is no exaggeration to say that probability theories have exerted astrong prescriptive influence on

MICHAEL J. SMITHSON

1997-01-01

369

The Probability of Causal Conditionals  

ERIC Educational Resources Information Center

Conditionals in natural language are central to reasoning and decision making. A theoretical proposal called the Ramsey test implies the conditional probability hypothesis: that the subjective probability of a natural language conditional, P(if p then q), is the conditional subjective probability, P(q [such that] p). We report three experiments on…

Over, David E.; Hadjichristidis, Constantinos; Evans, Jonathan St. B. T.; Handley, Simon J.; Sloman, Steven A.

2007-01-01

370

Risk-sensitive decision-making in patients with posterior parietal and ventromedial prefrontal cortex injury.  

PubMed

Successful choice under risk requires the integration of information about outcome probabilities and values and implicates a brain network including the ventromedial prefrontal cortex (vmPFC) and posterior parietal cortex (pPAR). Damage to the vmPFC is linked to poor decision-making and increased risk-taking. Electrophysiological and neuroimaging data implicate the pPAR in the processing of reward probability during choice, but the causal contribution of this area has not been established. We compared patients with lesions to the pPAR (n = 13), vmPFC (n = 13), and healthy volunteers (n = 22) on the Roulette Betting Task, a measure of risk-sensitive decision-making. Both lesion groups were impaired in adjusting their bets to the probability of winning. This impairment was correlated with the extent of pPAR, but not vmPFC, damage. In addition, the vmPFC group chose higher bets than healthy controls overall, an effect that correlated with lesion volume in the medial orbitofrontal cortex. Both lesion groups earned fewer points than healthy controls. The groups did not differ on 2 tasks assessing probabilistic reasoning outside of a risk-reward context. Our results demonstrate the causal involvement of both the pPAR and vmPFC in risk-sensitive choice and indicate distinguishable roles of these areas in probability processing and risk appetite. PMID:23926113

Studer, Bettina; Manes, Facundo; Humphreys, Glyn; Robbins, Trevor W; Clark, Luke

2015-01-01

371

Accurate extraction of the News  

E-print Network

We propose a new scheme for extracting gravitational radiation from a characteristic numerical simulation of a spacetime. This method is similar in conception to our earlier work but analytical and numerical implementation is different. The scheme is based on direct transformation to the Bondi coordinates and the gravitational waves are extracted by calculating the Bondi news function in Bondi coordinates. The entire calculation is done in a way which will make the implementation easy when we use uniform Bondi angular grid at $\\mathcal I^+$. Using uniform Bondi grid for news calculation has added advantage that we have to solve only ordinary differential equations instead of partial differential equation. For the test problems this new scheme allows us to extract gravitational radiation much more accurately than the previous schemes.

Shrirang S. Deshingkar

2006-09-14

372

Guidelines for accurate TOD measurement  

NASA Astrophysics Data System (ADS)

Guidelines to perform Triangle Orientation Discrimination (TOD) measurements are given in the present paper. The optimal range of test pattern sizes and contrasts are specified, as well as the required number of presentations for a threshold estimate. Special attention is paid to the statistical analysis. A standard frequency-of-serving curve is fitted to the observer data in order to obtain 75%- correct thresholds. A (chi) 2-statistic provides an objective criterion for acceptance or rejection of the threshold estimates. Finally, a complete TOD curve is obtained by fitting a weighted least-square polynomial through the 75%-correct thresholds. Further, a simple Go- NoGo screening procedure with objective pass/fail criteria, based on the TOD methodology, is proposed. With the TOD methodology, accurate sensor performance measured and Go- NoGo testing have become very easy to carry out. Therefore, the investment in a thoroughly design measurement setup will apply itself back easily.

Bijl, Piet; Valeton, J. M.

1999-07-01

373

Seismic Hazard Assessment: Conditional Probability  

NSDL National Science Digital Library

In this exercise, students investigate the use of conditional probability (the likelihood that a given event will occur within a specified time period) in assessing earthquake hazards. Introductory materials explain that conditional probability is based on the past history of earthquakes in a region and on how and when earthquakes recur; and discuss the different types of models that can be developed to predict recurrences. Using a table of probability values, students will calculate probabilities for earthquakes along the San Andreas and Wasatch Fault zones, and calculate probabilities that they will exceed a given acceleration (ground shaking) value. Example problems and a bibliography are provided.

Pinter, Nicholas

374

Statistical Shape and Probability Prior Model for Automatic Prostate Segmentation  

E-print Network

Statistical Shape and Probability Prior Model for Automatic Prostate Segmentation Soumya Ghose--Accurate prostate segmentation in Trans Rectal Ultra Sound (TRUS) images is an important step in different clinical artifacts like shadow, and speckle. Significant variations in prostate shape, size and contrast between

Paris-Sud XI, Université de

375

Computation of blocking probability for large circuit switched networks  

E-print Network

--The ever-growing Internet and the mounting evi- dence to the important role of circuit switching motivate demonstrate for NSFNet and Internet2 accurate calculations of the blocking probability using simulations, EFPA is unattainable, we propose, in this paper, to use an asymptotic approximation, which we call A-EFPA, for the link

Zukerman, Moshe

376

Probability workshop to be better in probability topic  

NASA Astrophysics Data System (ADS)

The purpose of the present study was to examine whether statistics anxiety and attitudes towards probability topic among students in higher education level have an effect on their performance. 62 fourth semester science students were given statistics anxiety questionnaires about their perception towards probability topic. Result indicated that students' performance in probability topic is not related to anxiety level, which means that the higher level in statistics anxiety will not cause lower score in probability topic performance. The study also revealed that motivated students gained from probability workshop ensure that their performance in probability topic shows a positive improvement compared before the workshop. In addition there exists a significance difference in students' performance between genders with better achievement among female students compared to male students. Thus, more initiatives in learning programs with different teaching approaches is needed to provide useful information in improving student learning outcome in higher learning institution.

Asmat, Aszila; Ujang, Suriyati; Wahid, Sharifah Norhuda Syed

2015-02-01

377

The effect of deacetylated gellan gum on aesculin distribution in the posterior segment of the eye after topical administration.  

PubMed

The aim of the present work was to evaluate the effect of deacetylated gellan gum on delivering hydrophilic drug to the posterior segment of the eye. An aesculin-containing in situ gel based on deacetylated gellan gum (AG) was prepared and characterized. In vitro corneal permeation across isolated rabbit cornea of aesculin between AG and aesculin solution (AS) was compared. The results showed that deacetylated gellan gum promotes corneal penetration of aesculin. Pharmacokinetics and ocular tissue distribution of aesculin after topical administration in rabbit eye showed that AG greatly improved aesculin accumulation in posterior segmentsrelative to AS, which was probably attributed to conjunctivital/sclera pathway. The area-under-the-curve (AUC) for AG in aqueous humor, choroid-retina, sclera and iris-ciliary body were significantly larger than those of AS. AG can be used as a potential carrier for broading the application of aesculin. PMID:22643053

Chen, Qiuhong; Zheng, Yu; Li, Ye; Zeng, Ying; Kuang, Jianchao; Hou, Shixiang; Li, Xiaohui

2012-05-01

378

Ultrasound elasticity imaging of human posterior tibial tendon  

NASA Astrophysics Data System (ADS)

Posterior tibial tendon dysfunction (PTTD) is a common degenerative condition leading to a severe impairment of gait. There is currently no effective method to determine whether a patient with advanced PTTD would benefit from several months of bracing and physical therapy or ultimately require surgery. Tendon degeneration is closely associated with irreversible degradation of its collagen structure, leading to changes to its mechanical properties. If these properties could be monitored in vivo, it could be used to quantify the severity of tendonosis and help determine the appropriate treatment. Ultrasound elasticity imaging (UEI) is a real-time, noninvasive technique to objectively measure mechanical properties in soft tissue. It consists of acquiring a sequence of ultrasound frames and applying speckle tracking to estimate displacement and strain at each pixel. The goals of my dissertation were to 1) use acoustic simulations to investigate the performance of UEI during tendon deformation with different geometries; 2) develop and validate UEI as a potentially noninvasive technique for quantifying tendon mechanical properties in human cadaver experiments; 3) design a platform for UEI to measure mechanical properties of the PTT in vivo and determine whether there are detectable and quantifiable differences between healthy and diseased tendons. First, ultrasound simulations of tendon deformation were performed using an acoustic modeling program. The effects of different tendon geometries (cylinder and curved cylinder) on the performance of UEI were investigated. Modeling results indicated that UEI accurately estimated the strain in the cylinder geometry, but underestimated in the curved cylinder. The simulation also predicted that the out-of-the-plane motion of the PTT would cause a non-uniform strain pattern within incompressible homogeneous isotropic material. However, to average within a small region of interest determined by principal component analysis (PCA) would improve the estimation. Next, UEI was performed on five human cadaver feet mounted in a materials testing system (MTS) while the PTT was attached to a force actuator. A portable ultrasound scanner collected 2D data during loading cycles. Young's modulus was calculated from the strain, loading force and cross sectional area of the PTT. Average Young's modulus for the five tendons was (0.45+/-0.16GPa) using UEI. This was consistent with simultaneous measurements made by the MTS across the whole tendon (0.52+/-0.18GPa). We also calculated the scaling factor (0.12+/-0.01) between the load on the PTT and the inversion force at the forefoot, a measurable quantity in vivo. This study suggests that UEI could be a reliable in vivo technique for estimating the mechanical properties of the human PTT. Finally, we built a custom ankle inversion platform for in vivo imaging of human subjects (eight healthy volunteers and nine advanced PTTD patients). We found non-linear elastic properties of the PTTD, which could be quantified by the slope between the elastic modulus (E) and the inversion force (F). This slope (DeltaE/DeltaF), or Non-linear Elasticity Parameter (NEP), was significantly different for the two groups: 0.16+/-0.20 MPa/N for healthy tendons and 0.45+/-0.43 MPa/N for PTTD tendons. A receiver operating characteristic (ROC) curve revealed an area under the curve (AUC) of 0.83+/-0.07, which indicated that the classifier system is valid. In summary, the acoustic modeling, cadaveric studies, and in vivo experiments together demonstrated that UEI accurately quantifies tendon mechanical properties. As a valuable clinical tool, UEI also has the potential to help guide treatment decisions for advanced PTTD and other tendinopathies.

Gao, Liang

379

How accurate is Limber's equation?  

E-print Network

The so-called Limber equation is widely used in the literature to relate the projected angular clustering of galaxies to the spatial clustering of galaxies in an approximate way. This paper gives estimates of where the regime of applicability of Limber's equation stops. Limber's equation is accurate for small galaxy separations but breaks down beyond a certain separation that depends mainly on the ratio sigma/R and to some degree on the power-law index, gamma, of spatial clustering xi; sigma is the one-sigma width of the galaxy distribution in comoving distance, and R the mean comoving distance. As rule-of-thumb, a 10% relative error is reached at 260 sigma/R arcmin for gamma~1.6, if the spatial clustering is a power-law. More realistic xi are discussed in the paper. Limber's equation becomes increasingly inaccurate for larger angular separations. Ignoring this effect and blindly applying Limber's equation can possibly bias results for the inferred spatial correlation. It is suggested to use in cases of doubt, or maybe even in general, the exact equation that can easily be integrated numerically in the form given in the paper.

P. Simon

2007-08-24

380

How Accurate Is Peer Grading?  

PubMed Central

Previously we showed that weekly, written, timed, and peer-graded practice exams help increase student performance on written exams and decrease failure rates in an introductory biology course. Here we analyze the accuracy of peer grading, based on a comparison of student scores to those assigned by a professional grader. When students graded practice exams by themselves, they were significantly easier graders than a professional; overall, students awarded ?25% more points than the professional did. This difference represented ?1.33 points on a 10-point exercise, or 0.27 points on each of the five 2-point questions posed. When students graded practice exams as a group of four, the same student-expert difference occurred. The student-professional gap was wider for questions that demanded higher-order versus lower-order cognitive skills. Thus, students not only have a harder time answering questions on the upper levels of Bloom's taxonomy, they have a harder time grading them. Our results suggest that peer grading may be accurate enough for low-risk assessments in introductory biology. Peer grading can help relieve the burden on instructional staff posed by grading written answers—making it possible to add practice opportunities that increase student performance on actual exams. PMID:21123695

Parks, John W.

2010-01-01

381

A Simple Approach to Specimen Retrieval via Posterior Colpotomy Incision  

PubMed Central

Introduction: Posterior colpotomy incision for specimen retrieval is infrequently used in gynecologic laparoscopic surgery unless a concomitant hysterectomy is performed. We aim to describe a simple and unique technique for creating the colpotomy incision and to describe intraoperative and postoperative outcomes. Methods: Fifty patients underwent adnexal specimen retrieval through a posterior colpotomy incision. After devascularization and detachment of the adnexal specimen, the posterior cul-de-sac was visualized. The colpotomy incision was created by introducing a 12- or 15-mm laparoscopic trocar through the vagina into the posterior vaginal fornix under direct visualization. Specimens were placed into laparoscopic bags and removed through the vagina. The colpotomy incision was closed vaginally. Charts were reviewed for intraoperative and postoperative outcomes. Results: Twenty-nine women underwent adnexal surgery for an adnexal mass, 14 women underwent surgery for pelvic pain, and 7 women underwent adnexal surgery for primary prevention of malignancy. The specimens removed ranged in size from 2 to 16 cm (mean 5.7). The mean time patients were under anesthesia was 103 minutes (SD 57.3). There were no operative complications related to the colpotomy incision and no cases of postoperative vaginal cellulitis or pelvic infection were reported. Only 1 woman with a prior vaginal delivery reported dyspareunia postoperatively. Conclusion: This simple technique for posterior colpotomy incision can easily be added to the gynecologic surgeon's armamentarium and can be safely used for most women.

Menderes, Gulden; Tower, Amanda M.; Silasi, Dan-Arin; Azodi, Masoud

2015-01-01

382

Cardiorespiratory fitness in survivors of pediatric posterior fossa tumor.  

PubMed

Advances in medical therapies have greatly improved survivorship rates in children diagnosed with brain tumor; as a result, morbidities associated with survivorship have become increasingly important to identify and address. In general, pediatric posterior fossa tumor survivors tend to be less physically active than peers. This may be related to late effects of diagnosis and treatment, including cardiovascular, endocrine, psychological, and neurocognitive difficulties. Exercise has been shown to be effective in improving physical functioning, mood, and even cognitive functioning. Consequently, the benefits of physical exercise need to be explored and incorporated into the daily lives of pediatric posterior fossa tumor survivors. The primary aim of the present study was to establish the feasibility and safety of cardiorespiratory fitness testing in pediatric posterior fossa tumor survivors who had received cranial radiation therapy. In addition, comparing our cohort with previously published data, we found that pediatric posterior fossa tumor survivors tended to be less fit than children with pulmonary disease and healthy controls and approximately as fit as children with chronic heart disease and survivors of other types of childhood cancer. The importance of cardiorespiratory fitness in pediatric posterior fossa tumor survivors is discussed along with implications for future directions. PMID:22810754

Wolfe, Kelly R; Hunter, Gary R; Madan-Swain, Avi; Reddy, Alyssa T; Baños, James; Kana, Rajesh K

2012-08-01

383

External Dacryocystorhinostomy with and Without Suturing the Posterior Mucosal Flaps  

PubMed Central

ABSTRACT Purpose: To evaluate the outcome of the external dacryocystorhinostomy with and without suturing the posterior mucosal flaps. Methods: This study included 106 patients with lacrimal drainage system disorders who underwent the external dacryocystorhinostomy. Fifty four patients (Group A) underwent external dacryocystorhinostomy with suturing anterior and posterior flaps of the lacrimal sac and nasal mucosa, and the results obtained were compared with those of another series of 52 patients (Group B) where dacryocystorhinostomy was performed with suturing only the anterior flaps, whereas posterior mucosal flaps were excised. Results: The success rate was evaluated by lacrimal patency to irrigation and relief of epiphora. Patency achieved in groups A and B was 94.4% and 96.2%, respectively. There was no statistically significant difference in success rate between the groups. Conclusion: Our study suggests that external dacryocystorhinostomy with suturing anterior and posterior flaps have no advantage over dacryocystorhinostomy with suturing only anterior flaps. Anastomosis by suturing only anterior flaps and excision of the posterior flaps is easier to perform and may improve the success rate of external dacryocystorhinostomy. PMID:24783915

Kaçaniku, Gazmend; Begolli, Ilir

2014-01-01

384

Nonanatomic Location of the Posterior Horn of a Medial Meniscal Autograft  

E-print Network

Nonanatomic Location of the Posterior Horn of a Medial Meniscal Autograft Implanted in a Cadaveric of the posterior horn may oc- cur during arthroscopic implantation of a meniscal transplant. The objective with the posterior horn tunnel in non- anatomic locations (5 mm medial and 5 mm posterior) and in the anatomic

Hull, Maury

385

Maxillary Posterior Teeth Removal Without Palatal Injection –Truth or Myth: A Dilemma for Oral Surgeons  

PubMed Central

Background: Pain control is one of the most important factors for successful treatment. Each new measure to control pain has been looked as miraculous act at the initial stages. The improvements in agents and techniques for local anaesthesia are probably the most important advances in dental science to have occurred in the past years. Aim: To evaluate 4% articaine hydrochloride against 2% lignocaine hydrochloride anaesthesia in providing adequate palatal anaesthesia in maxillary posterior regions, without the need for a palatal block. Settings and Design: Healthy patients above 15 y of age and requiring bilateral extraction of their maxillary posterior teeth were included in this crossover study. The exclusion criteria included medical history of cardiovascular and kidney diseases, gastrointestinal bleeding or ulceration, allergic reactions to local anaesthetic, pregnancy or current lactation. Materials and Methods: Eighty patients, requiring bilateral extraction of their teeth due to various reasons were enrolled for this study. Each patient received both lignocaine and articaine anaesthetic in equivalent dose at two different appointments. Maxillary infiltration technique was used for extraction of maxillary posterior teeth at both the appointments. A 170-mm Heft Parker visual analogue scale was used to assess the pain on the palatal mucosa after buccal infiltration of either anaesthetic agent. Blood pressure, Pulse rate and electrocardiographic monitoring were done during the procedure. Adverse effects during the study period were also monitored. Statistical Analysis: Data was analysed by Z-test and student’s t-test. Results: Pain scores on probing palatal mucosa after buccal infiltration of the anaesthetic were more for lignocaine as compare to articaine and it was statistically significant (p <.001). However, for hemodynamic parameters and electrocardiographic monitoring, there was no statistically significant difference in blood pressure, pulse rate and electrocardiograph before and after the completion of extraction (p > 0.05). Conclusion: Four percent articaine offers better clinical performance than 2% Lignocaine, particularly in terms of providing adequate palatal anaesthesia with only buccal infiltration. PMID:25584295

Sharma, Amit; Aseri, ML; Batta, Angelika; Singh, Vikas; Pilania, Dinesh; Kumar Sharma, Yogesh

2014-01-01

386

TransMedial All-Inside Posterior Cruciate Ligament Reconstruction Using a Reinforced Tibial Inlay Graft  

PubMed Central

Surgical reconstruction of the posterior cruciate ligament (PCL) is technically demanding. Potential challenges include visualization of the tibial footprint and drilling of the tibial tunnel without damaging posterior neurovascular structures, as well as graft selection, deployment, tensioning, and fixation. We present a novel TransMedial all-inside arthroscopic technique (technique designed by A. J. Wilson with support from Arthrex) using a single hamstring tendon graft, fixed with adjustable cortical suspensory devices. The technique simplifies the difficult steps encountered during PCL reconstruction and is safe and reproducible. All arthroscopic viewing is accomplished from the lateral portal, and femoral socket preparation is performed from the medial side with specially contoured instruments, which allow accurate marking, measuring, and anatomic positioning of the graft. The quadrupled semitendinosus graft can be augmented with composite polymer tape for increased strength and initial stability. We use outside-in drilling to create retrograde femoral and tibial sockets. Cortical suspensory fixation on the tibial side can be supplemented with anchor fixation. We use an arthroscopic tibial inlay technique that better approximates native knee anatomy. This also avoids the “killer turn,” a problem seen in transtibial PCL reconstruction techniques, which theoretically induces graft laxity due to abrasion with cyclic loading. This technique can be further adapted to allow a modified double-bundle or TriLink graft (technique designed by A. J. Wilson with support from Arthrex.). PMID:24400186

Nancoo, Tamara J.; Lord, Breck; Yasen, Sam K.; Smith, James O.; Risebury, Michael J.; Wilson, Adrian J.

2013-01-01

387

Combining Probability Forecasts and Understanding Probability Extremizing through Information Diversity  

E-print Network

(shifting it closer to its nearest extreme) varies as a function of the experts' information overlap. Our this links theory to practice and largely determines the predictive performance of the resulting probability). They consider a probability forecast "interpreted" if the expert forms it based on a personal interpretation

Pemantle, Robin

388

American Mathematical Society: Probability Web  

NSDL National Science Digital Library

The Probability Web is maintained by a professor in the Mathematics and Computer Science Department at Carleton College and offers links and resources for researchers, teachers, and others interested in probability. Links to an abstract database, book lists, conferences, jobs, journals, newsgroups, teaching resources and other miscellaneous online resources are included. In some cases early chapters of books are posted and some journals are free. Also interesting is the alphabetical listing of People in Probability, which includes links to mathematicians' websites. Another section provides favorite quotes on probability submitted by visitors.

Pollett, Phil

389

Posterior predictive checks of tetrad subsets for covariance structures of measurement models.  

PubMed

Confirmatory tetrad analysis is based on tetrads that are assumed to be 0 or to "vanish" under an assumed model to test the goodness of fit of a model or the relative fit of nested models. A strength of a tetrad-based approach to model fit assessment over standard methods is that researchers can evaluate the plausibility of a theoretical model structure when estimation or identification is problematic. Previous research has developed confirmatory tetrad analysis for covariance structures using asymptotic and bootstrap sampling distributions for omnibus test statistics for all vanishing tetrads. We extend confirmatory tetrad analysis in 2 ways. First, we develop an approach to confirmatory tetrad analysis based on posterior predictive checks for Bayesian probability models using tetrads to construct discrepancy measures. Second, we show how the discrepancy measure for all vanishing tetrads can be additively decomposed into measures for subsets of tetrads using a typology of tetrads proposed by Kenny (1979). We show that posterior predictive checks using a hierarchy of subsets of tetrads from this typology can be effectively used to identify potential and specific sources for lack of fit. We demonstrate the utility of this approach with classic data sets from the literature and with simulated data. PMID:23527604

Johnson, Timothy R; Bodner, Todd E

2013-12-01

390

Sensitivity of posterior parameter correlations and response parameter correlations to prior response uncertainty  

SciTech Connect

The two parameters one response model of the generalized linear least squares parameter adjustment methodology was used in order to analyze the procedure of improving cross sections agreement with integral experimental results. Two extreme adjustment cases were considered. One case is using extremely accurate measured integral responses, such as k{sub eff} of Godiva or Jezebel for instance. The other one is modifying only one parameter, for instance the modification of {nu}-bar in ENDF/B-VII, in order to improve agreement of calculated responses with corresponding integral measurements results. In both cases new posterior parameters correlations are generated. The conclusion is that it is not advised to use integral measurements information in the evaluation process of a general purpose nuclear data file. (authors)

Wagschal, J. J. [Racah Inst. of Physics, Hebrew Univ. of Jerusalem, Edmond J. Safra Campus, Jerusalem, 91904 (Israel)

2012-07-01

391

Quantification of Posterior Globe Flattening: Methodology Development and Validation  

NASA Technical Reports Server (NTRS)

Microgravity exposure affects visual acuity in a subset of astronauts and mechanisms may include structural changes in the posterior globe and orbit. Particularly, posterior globe flattening has been implicated in the eyes of several astronauts. This phenomenon is known to affect some terrestrial patient populations and has been shown to be associated with intracranial hypertension. It is commonly assessed by magnetic resonance imaging (MRI), computed tomography (CT) or B-mode Ultrasound (US), without consistent objective criteria. NASA uses a semiquantitative scale of 0-3 as part of eye/orbit MRI and US analysis for occupational monitoring purposes. The goal of this study was ot initiate development of an objective quantification methodology to monitor small changes in posterior globe flattening.

Lumpkins, Sarah B.; Garcia, Kathleen M.; Sargsyan, Ashot E.; Hamilton, Douglas R.; Berggren, Michael D.; Ebert, Douglas

2012-01-01

392

Quantification of Posterior Globe Flattening: Methodology Development and Validationc  

NASA Technical Reports Server (NTRS)

Microgravity exposure affects visual acuity in a subset of astronauts, and mechanisms may include structural changes in the posterior globe and orbit. Particularly, posterior globe flattening has been implicated in several astronauts. This phenomenon is known to affect some terrestrial patient populations, and has been shown to be associated with intracranial hypertension. It is commonly assessed by magnetic resonance imaging (MRI), computed tomography (CT), or B-mode ultrasound (US), without consistent objective criteria. NASA uses a semi-quantitative scale of 0-3 as part of eye/orbit MRI and US analysis for occupational monitoring purposes. The goal of this study was to initiate development of an objective quantification methodology for posterior globe flattening.

Lumpkins, S. B.; Garcia, K. M.; Sargsyan, A. E.; Hamilton, D. R.; Berggren, M. D.; Antonsen, E.; Ebert, D.

2011-01-01

393

Posterior arm shoulder dystocia alleviated by the Zavanelli maneuver.  

PubMed

The exact role of the Zavanelli maneuver for the management of shoulder dystocia still remains to be defined. None of the previously reported cases in which the Zavanelli maneuver has been employed described impaction of posterior fetal arm. At 40 weeks' gestation, a nulliparous patient with gestational diabetes, who underwent vacuum delivery, delivered an infant with shoulder dystocia. McRoberts' maneuver, suprapubic pressure, midline episiotomy, and Woods' maneuver were all unsuccessful in alleviating the shoulder dystocia. The posterior fetal arm was noted to be persistently impacted, so the Zavanelli maneuver was used to deliver an unsuspected macrosomic (4215 g) infant. The newborn, at the age of 3 years, has a right Erb's palsy. The Zavanelli maneuver can be used to alleviate a posterior arm shoulder dystocia, though there may be concomitant neurological injury. PMID:20414853

Gherman, Robert B; Ouzounian, Joseph G; Chauhan, Suneet

2010-10-01

394

Endothelin: A novel peptide in the posterior pituitary system  

SciTech Connect

Endothelin (ET), originally characterized as a 21-residue vasoconstrictor peptide from endothelial cells, is present in the porcine spinal cord and may act as a neuropeptide. Endothelin-like immunoreactivity has now been demonstrated by immunohistochemistry in the paraventricular and supraoptic nuclear neurons and their terminals in the posterior pituitary of the pig and the rat. The presence of ET in the porcine hypothalamus was confirmed by reversed-phase high-pressure liquid chromatography and radioimmunoassay. Moreover, in situ hybridization demonstrated ET messenger RNA in porcine paraventricular nuclear neurons. Endothelin-like immunoreactive products in the posterior pituitary of the rat were depleted by water deprivation, suggesting a release of ET under physiological conditions. These findings indicate that ET is synthesized in the posterior pituitary system and may be involved in neurosecretory functions.

Yoshizawa, Toshihiro; Kanazawa, Ichiro; Shinmi, Osamu; Kimura, Sadao; Yanagisawa, Masashi; Masaki, Tomoh; Uchiyama, Yasuo (Univ. of Tsukuba (Japan)); Giaid, A.; Gibson, S.J.; Polak, J.M. (Royal Postgraduate Medical School, London (England))

1990-01-26

395

Posterior Interosseous Forearm Flap in Reconstruction of First Web Space  

PubMed Central

Summary Use of a fascial flap is often required for reconstruction of a skin defect on the dorsum of the hand. For this purpose, a distally based dorsal forearm fasciosubcutaneous flap based on the perforators of the posterior interosseous artery was developed. The distally based dorsal forearm fasciosubcutaneous flap and especially the posterior interosseous artery flap are a convenient and reliable alternative for reconstructing skin defects of the hand after the release of post-burn adduction contracture of web space I involving vital structure exposure. Although the posterior interosseous artery flap is suitable for covering dorsal skin defects of the hand and avoids interference with the forearm's two main arteries, the dissection of the vascular pedicle is frequently quite complex and tedious. PMID:21991164

Kola, N.; Isaraj, S.; Xhepa, G.; Belba, M.; Belba, G.

2009-01-01

396

The relationship between species detection probability and local extinction probability  

USGS Publications Warehouse

In community-level ecological studies, generally not all species present in sampled areas are detected. Many authors have proposed the use of estimation methods that allow detection probabilities that are <1 and that are heterogeneous among species. These methods can also be used to estimate community-dynamic parameters such as species local extinction probability and turnover rates (Nichols et al. Ecol Appl 8:1213-1225; Conserv Biol 12:1390-1398). Here, we present an ad hoc approach to estimating community-level vital rates in the presence of joint heterogeneity of detection probabilities and vital rates. The method consists of partitioning the number of species into two groups using the detection frequencies and then estimating vital rates (e.g., local extinction probabilities) for each group. Estimators from each group are combined in a weighted estimator of vital rates that accounts for the effect of heterogeneity. Using data from the North American Breeding Bird Survey, we computed such estimates and tested the hypothesis that detection probabilities and local extinction probabilities were negatively related. Our analyses support the hypothesis that species detection probability covaries negatively with local probability of extinction and turnover rates. A simulation study was conducted to assess the performance of vital parameter estimators as well as other estimators relevant to questions about heterogeneity, such as coefficient of variation of detection probabilities and proportion of species in each group. Both the weighted estimator suggested in this paper and the original unweighted estimator for local extinction probability performed fairly well and provided no basis for preferring one to the other.

Alpizar-Jara, R.; Nichols, J.D.; Hines, J.E.; Sauer, J.R.; Pollock, K.H.; Rosenberry, C.S.

2004-01-01

397

Barentsz is essential for the posterior localization of oskar mRNA and colocalizes with it to the posterior pole  

PubMed Central

The localization of Oskar at the posterior pole of the Drosophila oocyte induces the assembly of the pole plasm and therefore defines where the abdomen and germ cells form in the embryo. This localization is achieved by the targeting of oskar mRNA to the posterior and the localized activation of its translation. oskar mRNA seems likely to be actively transported along microtubules, since its localization requires both an intact microtubule cytoskeleton and the plus end–directed motor kinesin I, but nothing is known about how the RNA is coupled to the motor. Here, we describe barentsz, a novel gene required for the localization of oskar mRNA. In contrast to all other mutations that disrupt this process, barentsz-null mutants completely block the posterior localization of oskar mRNA without affecting bicoid and gurken mRNA localization, the organization of the microtubules, or subsequent steps in pole plasm assembly. Surprisingly, most mutant embryos still form an abdomen, indicating that oskar mRNA localization is partially redundant with the translational control. Barentsz protein colocalizes to the posterior with oskar mRNA, and this localization is oskar mRNA dependent. Thus, Barentsz is essential for the posterior localization of oskar mRNA and behaves as a specific component of the oskar RNA transport complex. PMID:11481346

van Eeden, Fredericus J.M.; Palacios, Isabel M.; Petronczki, Mark; Weston, Matthew J.D.; St Johnston, Daniel

2001-01-01

398

Retrograde cold blood cardioplegia. Obliteration of the posterior interventricular vein in the coronary sinus improves cooling of the left ventricle posterior wall  

Microsoft Academic Search

The study hypothesis was that obliteration of the posterior interventricular vein in the coronary sinus avoids the back leak of cardioplegia to the right atrium and forces cardioplegia towards the posterior wall of the left ventricle and interventricular septum. A new retrograde cardio**sofhyph**plegia cannula with a long balloon (3cm) was designed which obstructs the posterior interventricular vein in the coronary

E Bezon; J A. Barra; P Mondine; A Karaterki

1997-01-01

399

Infectious crystalline keratopathy predominantly affecting the posterior cornea  

PubMed Central

A case of infectious crystalline keratopathy that affects mainly the posterior stroma is presented. Crystalline infiltrates presented after multiple epithelial defects and chronic topical steroid use following a penetrating keratoplasty in this patient. His epithelial defects persisted and given the deep location of the crystalline infiltrates, a penetrating keratoplasty was performed again. Slit-lamp photo demonstrates the crystalline plaque. Confocal microscopy also documents the aggregates of crystal-like structures. Histology slides are also presented that show the disruption of the stromal-Descemet interface and the predominance of pathology confined to the posterior stroma which has been documented in the literature as a rare finding. PMID:25197405

Mesiwala, Nisreen K; Chu, Charleen T; Raju, Leela V

2014-01-01

400

Unusual presentation of poststreptococcal glomerulonephritis as posterior reversible encephalopathy syndrome  

PubMed Central

Posterior reversible encephalopathy syndrome (PRES) is a rare clinicoradiologic condition manifesting with headache, seizures, altered sensorium, visual disturbances, and characteristic lesions on neuroimaging predominantly affecting the posterior regions of the brain. We report a case of an 8-year-old boy with poststreptococcal glomerulonephritis, presenting as PRES. A magnetic resonance imaging showed hyperintense lesions in bilateral frontal and parietooccipital parenchyma on fluid-attenuated inversion recovery and T2-weighted images, suggestive of “PRES.” Patient made a complete neurological recovery without any deficit. PMID:24891903

Zaki, Syed Ahmed; Shanbag, Preeti

2014-01-01

401

Management of Posterior Reversible Syndrome in Preeclamptic Women  

PubMed Central

Posterior reversible encephalopathy syndrome (PRES) is a neurological syndrome associated with a number of conditions including preeclampsia. It is characterized by seizures, alteration of consciousness, visual disturbances, and symmetric white matter abnormalities, typically in the posterior parietooccipital regions of the cerebral hemispheres, at computed tomography (CT) and magnetic resonance (MRI). We report three new cases of PRES in preeclamptic patients and describe the management of these patients. We present a brief review of other cases in the literature, with particular attention to the anesthetic management. PMID:25506009

Poma, S.; Delmonte, M. P.; Gigliuto, C.; Imberti, R.; Delmonte, M.; Arossa, A.; Iotti, G. A.

2014-01-01

402

Posterior tibial tendon dysfunction in the adult: current concepts.  

PubMed

The management of posterior tibial tendon dysfunction in adults has evolved substantially, and controversy persists regarding a specific recommended algorithm for treatment. The current focus is on early diagnosis and treatment of this disorder with joint-sparing surgeries, such as corrective osteotomies and tendon transfers, when nonsurgical modalities have been exhausted. It is helpful to be familiar with the pertinent pathophysiology and diagnostic pearls associated with posterior tibial tendon dysfunction, its treatment options, pertinent literature, and technique tips for the procedures currently being used. PMID:25745927

Stein, Benjamin E; Schon, Lew C

2015-01-01

403

Rare Lipomatous Tumor of the Posterior Mediastinum in Children  

PubMed Central

The mediastinum is a unique anatomic area containing various structures and pluripotent cells, which allow for the development of a range of tumors. We report two pediatric cases of a lipomatous tumor of the posterior mediastinum. Complete surgical excision of the mass in each was achieved through a lateral thoracotomy. Histopathologic findings showed a lipoma in one case and a lipoblastoma in the other. A lipomatous tumor in the posterior mediastinum is extremely rare and preoperative diagnosis is difficult. When an operative plan is being considered, the presence of a potentially malignant tumor should be kept in mind. PMID:25755971

Homma, Takahiro; Doki, Yoshinori; Senda, Kazutaka; Toge, Masayoshi; Yamamoto, Yutaka; Ojima, Toshihiro; Shimada, Yoshifumi; Yoshimura, Naoki

2014-01-01

404

Pedicle screw-based posterior dynamic stabilization: literature review.  

PubMed

Posterior dynamic stabilization (PDS) indicates motion preservation devices that are aimed for surgical treatment of activity related mechanical low back pain. A large number of such devices have been introduced during the last 2 decades, without biomechanical design rationale, or clinical evidence of efficacy to address back pain. Implant failure is the commonest complication, which has resulted in withdrawal of some of the PDS devices from the market. In this paper the authors presented the current understanding of clinical instability of lumbar motions segment, proposed a classification, and described the clinical experience of the pedicle screw-based posterior dynamic stabilization devices. PMID:23227349

Sengupta, Dilip K; Herkowitz, Harry N

2012-01-01

405

Posterior shoulder dislocation while lifting weights: a missed diagnosis.  

PubMed

We present a case of a 24-year-old man who suffered acute shoulder pain and subsequent inability to move his arm while lifting weights in the bench-press position. He attended A&E where he was examined and X-rays were performed. He was diagnosed with presumed pectoralis major tendon rupture and was discharged to fracture clinic the following day with analgesia. On review in clinic he was found to have a posterior shoulder dislocation and was taken to theatre for relocation under anaesthesia. This case report examines the mechanism, investigations and management of posterior shoulder dislocation. PMID:24557475

Cuffolo, Giulio; Coomber, Ross; Burtt, Simon; Gray, Jim

2014-01-01

406

Posterior fossa neoplasm and PHACES syndrome: a case report.  

PubMed

A 4-year-old girl with PHACES syndrome (posterior fossa brain malformations, hemangiomas, arterial anomalies, cardiac anomalies/coarctation of the aorta, eye abnormalities, and sternal clefting/supraumbilical raphe) developed a cerebellar pilocytic astrocytoma 18 months after resolution of her neck, ear, and thoracic hemangiomas. Because cutaneous hemangiomas may have involuted by the time a patient is diagnosed with a central nervous system neoplasm, it seems possible that in other such patients the association may have gone unrecognized. Cerebellar pilocytic astrocytoma may be a rare manifestation of the posterior fossa malformations of PHACES. PMID:19262249

Wallen, Katharine E; Hadar, Eldad J; Perry, Victor; Bouldin, Thomas W; Loehr, James; Blatt, Julie

2009-03-01

407

Bilateral epididymitis in a child with undiagnosed posterior urethral valves.  

PubMed

Posterior urethral valves are most commonly detected in the early neonatal period, the diagnosis often antenatally suspected from ultrasound findings. Nevertheless, some cases might go undetected and become manifest later in life with lower urinary tract symptoms. We describe the unusual case of a 5-year-old boy with a 2-month history of bladder distension, urinary dribbling, and epididymitis. Cystourethrography revealed posterior urethral valves with reflux into the seminal vesicles, vas deferens, and epididymis, bilaterally. A review of the published data is provided in the context of this unusual presentation pattern. PMID:23477755

Kwong, Justin; Lorenzo, Armando J; DeMaria, Jorge; Braga, Luis H P

2013-07-01

408

Rare association of fetal posterior urethral valve with ureteric stricture  

PubMed Central

Background Amongst the various causes of obstructive uropathies, pelviureteric junction obstruction, bilateral ureterovesical junction obstruction and vesicoureteral reflux are common. The association of posterior urethral valve and ureteric stricture has not been reported so far. Case We report a rare case of fetal obstructive uropathy presenting as combination of ureteric stricture with posterior urethral valve and its consequences like cystic dysplastic kidneys and urinoma. Conclusion Combination of urinary malformation may be due to basic primary pathology and its secondary consequence at a distant site. PMID:22905302

Pradhan, Mandakini; Singh, Neeta; Singh, Asha Kumari; Kumari, Neeraj

2012-01-01

409

Posterior tibial vein aneurysm presenting as tarsal tunnel syndrome.  

PubMed

Tarsal tunnel syndrome is a compressive neuropathy of the posterior tibial nerve within the tarsal tunnel. Its etiology varies, including space occupying lesions, trauma, inflammation, anatomic deformity, iatrogenic injury, and idiopathic and systemic causes. Herein, we describe a 46-year-old man who presented with left foot pain. Work up revealed a venous aneurysm impinging on the posterior tibial nerve. Following resection of the aneurysm and lysis of the nerve, his symptoms were alleviated. Review of the literature reveals an association between venous disease and tarsal tunnel syndrome; however, this report represents the first case of venous aneurysm causing symptomatic compression of the nerve. PMID:25199522

Ayad, Micheal; Whisenhunt, Anumeha; Hong, EnYaw; Heller, Josh; Salvatore, Dawn; Abai, Babak; DiMuzio, Paul J

2014-09-01

410

Hip Arthroscopy for Challenging Deformities: Posterior Cam Decompression  

PubMed Central

Since the classic description of cam femoroacetabular impingement occurring in the anterolateral quadrant of the proximal femur, there has been growing evidence of cam impingement extending outside of this region. Although anteromedial cam decompression may be performed, posterior cam decompression is at higher theoretic risk of vascular embarrassment with osteonecrosis and/or tensile failure with fracture, leading some investigators to believe that these major deformities require open surgical correction. We present a less invasive method of arthroscopic posterior cam decompression using the modified midanterior portal while avoiding the posterolateral vasculature of the proximal femur. PMID:23802094

Matsuda, Dean K.; Hanami, Dylan

2013-01-01

411

Double triangular resection for a widely prolapsed posterior mitral leaflet.  

PubMed

A wide and redundant prolapse of the posterior mitral leaflet in active infective endocarditis cannot be easily repaired. A sliding plasty can be attempted, but the range of annular plication is often too large. Chordal replacement is another option, but is prone to long-term degeneration because the redundant leaflet still exists. Here, we describe a simple resection technique that utilizes only two small triangular resections. The resections are sutured with no need to shorten the annulus. The leaflet tissue between the two triangular resections must be preserved to make an appropriately shaped posterior leaflet. PMID:23223672

Sawazaki, Masaru; Tomari, Shiro; Tsunekawa, Tomohiro; Izawa, Naoto

2013-03-01

412

Pippi - painless parsing, post-processing and plotting of posterior and likelihood samples  

E-print Network

Interpreting samples from likelihood or posterior probability density functions is rarely as straightforward as it seems it should be. Producing publication-quality graphics of these distributions is often similarly painful. In this short note I describe pippi, a simple, publicly-available package for parsing and post-processing such samples, as well as generating high-quality PDF graphics of the results. Pippi is easily and extensively configurable and customisable, both in its options for parsing and post-processing samples, and in the visual aspects of the figures it produces. I illustrate some of these using an existing supersymmetric global fit, performed in the context of a gamma-ray search for dark matter. Pippi can be downloaded and followed at http://github.com/patscott/pippi .

Pat Scott

2012-10-03

413

The Posterior metric and the Goodness of Gibbsianness for transforms of Gibbs measures  

E-print Network

We present a general method to derive continuity estimates for conditional probabilities of general (possibly continuous) spin models sub jected to local transformations. Such systems arise in the study of a stochastic time-evolution of Gibbs measures or as noisy observations. We exhibit the minimal necessary structure for such double-layer systems. Assuming no a priori metric on the local state spaces, we define the posterior metric on the local image space. We show that it allows in a natural way to divide the local part of the continuity estimates from the spatial part (which is treated by Dobrushin uniqueness here). We show in the concrete example of the time evolution of rotators on the q-1 dimensional sphere how this method can be used to obtain estimates in terms of the familiar Euclidean metric.

C. Kuelske; A. A. Opoku

2007-11-23

414

Microcirculation of human fetal posterior root ganglia: a scanning electron microscopic study of corrosion casts.  

PubMed

The vasculature of lumbar posterior root ganglia was investigated in human fetuses aged 17-24 weeks; using the corrosion casting technique and scanning electron microscopy. The arterial supply consisted of one main artery and occasional arterioles entering the ganglion at its pole and running axially, while the venous drainage was located at the periphery of the ganglion, thus indicating a centrifugal pattern of blood flow. The dense capillary network of the ganglion showed the roughly parallel course of the vessels in the central zone and an irregular arrangement in the peripheral zone where capillaries formed "nests", probably surrounding individual perikaryons of ganglionic cells. The capillaries had a sinusoidal character with numerous dilatations about twice the normal capillary size, as well as occasional larger vascular spaces resulting from capillary interconnections and suggesting the intussusceptive type of angiogenesis. PMID:9488902

Gorczyca, J; Skawina, A; Litwin, J A; Miodo?ski, A J

1998-02-01

415

Probability of sea level rise  

SciTech Connect

The report develops probability-based projections that can be added to local tide-gage trends to estimate future sea level at particular locations. It uses the same models employed by previous assessments of sea level rise. The key coefficients in those models are based on subjective probability distributions supplied by a cross-section of climatologists, oceanographers, and glaciologists.

Titus, J.G.; Narayanan, V.K.

1995-10-01

416

Improving Aggregated Forecasts of Probability  

E-print Network

include "President Obama will be re- elected in 2012", "Obama will be re-elected if the U.S. unemploy, a user might be asked questions about simple events such as "What is the probability that Obama wins Indiana?" and also questions about complex events like "What is the probability that Obama wins Vermont

Osherson, Daniel

417

Ideas that Lead to Probability  

NSDL National Science Digital Library

This lesson is designed to introduce students to random numbers and fairness as a precursor to learning about probability. The lesson provides links to discussions and activities related to probability and fairness 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 this one.

2011-01-19

418

Maximum Probability Reaction Sequences in Stochastic Chemical Kinetic Systems  

PubMed Central

The detailed behavior of many molecular processes in the cell, such as protein folding, protein complex assembly, and gene regulation, transcription and translation, can often be accurately captured by stochastic chemical kinetic models. We investigate a novel computational problem involving these models – that of finding the most-probable sequence of reactions that connects two or more states of the system observed at different times. We describe an efficient method for computing the probability of a given reaction sequence, but argue that computing most-probable reaction sequences is EXPSPACE-hard. We develop exact (exhaustive) and approximate algorithms for finding most-probable reaction sequences. We evaluate these methods on test problems relating to a recently-proposed stochastic model of folding of the Trp-cage peptide. Our results provide new computational tools for analyzing stochastic chemical models, and demonstrate their utility in illuminating the behavior of real-world systems. PMID:21629860

Salehi, Maryam; Perkins, Theodore J.

2010-01-01

419

Maximum Probability Reaction Sequences in Stochastic Chemical Kinetic Systems  

PubMed Central

The detailed behavior of many molecular processes in the cell, such as protein folding, protein complex assembly, and gene regulation, transcription and translation, can often be accurately captured by stochastic chemical kinetic models. We investigate a novel computational problem involving these models – that of finding the most-probable sequence of reactions that connects two or more states of the system observed at different times. We describe an efficient method for computing the probability of a given reaction sequence, but argue that computing most-probable reaction sequences is EXPSPACE-hard. We develop exact (exhaustive) and approximate algorithms for finding most-probable reaction sequences. We evaluate these methods on test problems relating to a recently-proposed stochastic model of folding of the Trp-cage peptide. Our results provide new computational tools for analyzing stochastic chemical models, and demonstrate their utility in illuminating the behavior of real-world systems. PMID:21441987

Salehi, Maryam; Perkins, Theodore J.

2010-01-01

420

Abordaje posterior limitado del hombro: descripción anatómica y aplicación clínica  

Microsoft Academic Search

The purpose of this study was to describe a modified posterior approach to the shoulder and to present their clinical application in 12 cadaver specimens and a prospective series of 11 patients with glenoid fractures from 1994 to 2003. In the proposed approach Deltoid is reflected superiorly without detachment, approaching the interval between Infraspinatus and Teres Minor muscles exposing the

Smith Gamboa Jaimes; Fabio Suárez Romero; Año Ortopedia; Smith Gamboa

421

POSTERIOR PREDICTIVE ASSESSMENT OF MODEL FITNESS VIA REALIZED DISCREPANCIES  

Microsoft Academic Search

This paper considers Bayesian counterparts of the classical tests for good- ness of fit and their use in judging the fit of a single Bayesian model to the observed data. We focus on posterior predictive assessment, in a framework that also includes conditioning on auxiliary statistics. The Bayesian formulation facilitates the con- struction and calculation of a meaningful reference distribution

Andrew Gelman; Xiao-Li Meng; Hal Stern

1995-01-01

422

Posterior Predictive Model Checking for Multidimensionality in Item Response Theory  

ERIC Educational Resources Information Center

If data exhibit multidimensionality, key conditional independence assumptions of unidimensional models do not hold. The current work pursues posterior predictive model checking, a flexible family of model-checking procedures, as a tool for criticizing models due to unaccounted for dimensions in the context of item response theory. Factors…

Levy, Roy; Mislevy, Robert J.; Sinharay, Sandip

2009-01-01

423

Covering Your Posterior: Teaching Signaling Games Using Classroom Experiments  

ERIC Educational Resources Information Center

The author describes a protocol for classroom experiments for courses that introduce undergraduates to signaling games. Signaling games are conceptually difficult because, when analyzing the game, students are not naturally inclined to think in probabilistic, Bayesian terms. The experimental design explicitly presents the posterior frequencies of…

Turocy, Theodore L.

2009-01-01

424

Scleral fixation of dislocated posterior chamber intraocular lenses  

Microsoft Academic Search

Purpose: To report the results of managing dislocated posterior chamber intraocular lenses (PC IOLs) by externalizing the haptics through a clear corneal incision.Setting: The Retina Center at Pali Momi, Aiea, Hawaii, USA.Methods: This retrospective consecutive series comprised cases in which a dislocated PC IOL was managed with pars plana vitrectomy. With this method, the dislocated PC IOL is retrieved and

Gregg T Kokame; Izumi Yamamoto; Huck Mandel

2004-01-01

425

Posterior Cortical Atrophy: A Review of the Literature  

Microsoft Academic Search

The past three decades have seen an accumulation of reports of neurodegenerative disease with disruption to visual processing. Disorders of both visuospatial processing and visual recognition have been described, though the former predominate. But the conundrum of posterior cortical atrophy (PCA) is that while the clinical presentation is relatively homogeneous, the nosological status remains something of a puzzle. Many cases

Diana Caine

2004-01-01

426

Posterior Cortical Atrophy Variants of Alzheimer’s Disease  

Microsoft Academic Search

Posterior cortical atrophy (PCA) was first described by Benson in 1988 and, since then, has been regarded as a variant of Alzheimer’s disease. We present 2 patients with symptoms suggestive of PCA and 2 patients with apraxia as the initial manifestation. Primary motor and sensory modalities were intact. Mild memory impairment was present early in the course of the disease

Judith Aharon-Peretz; Ora Israel; Dorit Goldsher; Aharon Peretz

1999-01-01

427

Posterior cortical atrophy: Unusual feature of alzheimer's disease  

Microsoft Academic Search

We present two patients with symptoms suggestive of bilateral posterior cortical dysfunction: loss of topographic familiarity, alexla, progressive visual agnosia for objects and pictures, agraphia, visuospatial compromise. Colour agnosia and prosopagnosia were present in one case. Primary motor and sensory modalities were intact. Within a few years, constructional apraxia, Baht's syndrome, components of Gerstmann's syndrome and transcortical sensory aphasla progressively

Pascal Rogelet; Annette Delafosse; Alain Destee

1996-01-01

428

A systematic overview of the incidence of posterior capsule opacification  

Microsoft Academic Search

ObjectiveReported rates of posterior capsule opacification (PCO) vary widely and are based on various definitions of PCO, varying lengths and intervals of follow-up, and the use of different surgical techniques, intraocular lens (IOL) designs, and methods of IOL implantation. This study was designed to obtain a more precise overall estimate of the incidence of PCO and to explore factors that

Debra A Schaumberg; M. Reza Dana; William G Christen; Robert J Glynn

1998-01-01

429

Complete excision of a giant thyroid goiter in posterior mediastinum  

PubMed Central

Intrathoracic goiter is commonly located in the anterior mediastinum. Here we report a case of a 58-year-old Chinese male in whom we successfully removed the intrathoracic goiter and eased his dyspnea by a right posterolateral thoracotomy approach. Posterior mediastinal thyroid goiter with mediastinal compressive symptoms is an indication of surgery. PMID:24196135

2013-01-01

430

[Post-traumatic cholesteatoma with posterior fossa invasion].  

PubMed

Post-traumatic cholesteatomas are an extremely rare variety of secondary cholesteatomas. We present a case of a 51-year-old male with post-traumatic cholesteatoma with posterior fossa invasion of 30-year evolution that initially manifested as acute otomastoiditis and headache. Its physiopathology and clinical manifestations are discussed. PMID:20557873

Castillo-López, Irma Yolanda; Muñoz-Lozano, Adán G; Bonner-Osorio, Claudia B

2011-01-01

431

Differences between Anterior and Posterior Circulation Stroke in TOAST  

Microsoft Academic Search

Background and Purpose: Clinicians have tended to view anterior circulation (AC) and posterior circulation (PC) strokes as separate entities, with different underlying pathogenesis, natural histories, and potential responsiveness to interventions such as anticoagulation. We sought to explore differences between AC and PC stroke in the Trial of ORG 10172 in Acute Stroke Treatment (TOAST). Methods: For patients enrolled in TOAST,

R. B. Libman; T. G. Kwiatkowski; M. D. Hansen; W. R. Clarke; R. F. Woolson; H. P. Adams

2001-01-01

432

Posterior scleritis presenting as unilateral secondary angle-closure glaucoma.  

PubMed

The following is a case report of a 19-year-old male who presented with unilateral acute angle-closure glaucoma. Posterior scleritis was diagnosed based on clinical features and ultrasound B-scan. The acute angle closure attack and exudative retinal detachment completely resolved with use of oral corticosteroids. PMID:15510468

Jain, Sunil S; Rao, Prasan; Kothari, Kulin; Bhatt, Deepak; Jain, Sanjay

2004-09-01

433

Atrial natriuretic factor-like activity in rat posterior pituitary  

SciTech Connect

The presence of a biologically active peptide: Atrial Natriuretic Factor (ANF) has been demonstrated in rat and human circulation and ANF is considered now as a new hormone. ANF may be involved in body fluid regulation. A very sensitive radioimmunoassay for rat ANF allowed the authors to search for immunoreactive ANF (IR-ANF) in rat posterior pituitary. Serial dilutions of homogenates of rat posterior pituitary showed a good parallelism with a reference curve in a radioimmunoassay system. The IR-ANF was extracted from rat posterior pituitary homogenates by activated Vycor glass beads. The lyophilized extract was purified by HPLC on C/sub 18/ ..mu.. Bondapak column. The HPLC yielded two IR-ANF peaks. Both isolated ANF-like material showed biological activity. The IR-ANF eluted with 33% acetonitrile, inhibited ACTH-stimulated aldosterone secretion with a similar potency as synthetic (Arg 101 - Tyr 126) ANF (0.7 x 10/sup -10/M). A much less potent ANF-like material was found in the second peak eluted with 36% acetonitrile. They conclude that ANF-like material is present in rat posterior pituitary and this suggest a possible role in ANF on AVP secretion directly in situ.

Gutkowska, J.; Debinski, W.; Racz, K.; Thibault, G.; Garcia, R.; Kuchel, O.; Genest, J.; Cantin, M.

1986-03-05

434

Blood Vessels of the Fetal Pig Dissection Posterior Vessels Protocol  

E-print Network

Blood Vessels of the Fetal Pig Dissection Posterior Vessels Protocol: 1. The blood vessels membrane is the peritoneum, the blood vessels are said to be retroperitoneal). In order to see the blood that supplies the stomach, liver and spleen with blood. This is the celiac artery. c. Just below where

Loughry, Jim

435

Spectrum of the Posterior Inferior Cerebellar Artery Territory Infarcts  

Microsoft Academic Search

Background and Purpose: The clinical, etiological and stroke mechanisms are defined well before but the detailed clinical and etiologic mechanisms regarding to all clinical spectrum of posterior inferior cerebellar artery (PICA) infarcts were not systematically studied by diffusion-weighted imaging (DWI). Methods: Seventy-four patients with PICA territory ischemic lesion proved by DWI with decreased apparent diffusion coefficient and FLAIR (fluid attenuation

Emre Kumral; Ceyla Ataç; Nilgün Yünten

2005-01-01

436

Cadherin-mediated adhesion regulates posterior body formation  

Microsoft Academic Search

BACKGROUND: The anterior-posterior axis of the vertebrate embryo undergoes a dramatic elongation during early development. Convergence and extension of the mesoderm, occurring during gastrulation, initiates the narrowing and lengthening of the embryo. However the lengthening of the axis continues during post-gastrula stages in the tailbud region, and is thought to involve convergent extension movements as well as other cell behaviors

Michael J Harrington; Elim Hong; Oluwafoyinsa Fasanmi; Rachel Brewster

2007-01-01

437

The role of wnt8 in posterior mesoderm formation  

E-print Network

due to reduced Bmp activity. The objective of this thesis is to test the hypothesis that zygotic Wnt signaling plays two critical functions: to restrict the size of the organizer and to promote posterior mesoderm development in a Bmp-independent manner...

Kelton, Cathryn Renee

2009-05-15

438

Reduced Neuronal Size in Posterior Hippocampus of Schizophrenic Patients  

Microsoft Academic Search

The hippocampus, an integral component of the corticolimbic circuitry of the brain, has been recently implicated in the pathophysiology of schizophrenia. This article has employed quantitative morphometric techniques to determine whether abnormalities of posterior hippocampal cross-sectional area, as well as the number, size, and degree of disarray of pyramidal neurons were present in 9 control and 14 schizophrenic subjects. Seven

Francine M. Benes; Ingrid Sorensen; Edward D. Bird

1991-01-01

439

Long-term stability of unilateral posterior crossbite correction  

Microsoft Academic Search

OBJECTIVE: To evaluate the stability of orthodontically corrected unilateral posterior crossbite in patients treated either by rapid maxillary expansion or with slow expansion devices in the early (mean age 7.2 years, n = 50) or late mixed dentition (mean age 9.9 years, n = 50). MATERIALS AND METHODS: The observation periods were approximately 8 years for the early treatment groups

Theodosia Bartzela; Irmtrud Jonas

2007-01-01

440

Pigmentary glaucoma associated with posterior chamber intraocular lenses.  

PubMed

Six cases of glaucoma associated with pigment dispersion syndrome occurred after the implantation of posterior chamber intraocular lenses. All six patients had iris transillumination defects associated with the intraocular lens haptics, increased intraocular pressure, and pigment deposition in the trabecular meshwork and the anterior chamber. Medication controlled the glaucoma and none of the patients required further surgery. PMID:4037024

Samples, J R; Van Buskirk, E M

1985-09-15

441

Distinguishing torpedo maculopathy from similar lesions of the posterior segment.  

PubMed

Torpedo maculopathy is a congenital solitary, oval-shaped lesion typically located temporal to the center of the macula. Congenital hypertrophy of the retinal pigment epithelium (RPE), RPE lesions of Gardner syndrome, and other lesions can present with similar characteristics. Because of its unique clinical and imaging features, torpedo maculopathy generally can be differentiated from other posterior segment lesions. PMID:24738480

Villegas, Victor M; Schwartz, Stephen G; Flynn, Harry W; Capó, Hilda; Berrocal, Audina M; Murray, Timothy G; Harbour, J William

2014-01-01

442

Impact of Selective Posterior Rhizotomy on Fine Motor Skills  

Microsoft Academic Search

Suprasegmental effects following selective posterior rhizotomy have been frequently reported. However, few studies have used validated functional outcome measures to report the surgical results beyond 3 years. The authors analyzed data obtained from the McGill Rhizotomy Database to determine the long-term impact of lumbosacral dorsal rhizotomy on fine motor skills. The study population comprised children with debilitating spasticity who underwent

Sandeep Mittal; Jean-Pierre Farmer; Borhan Al-Atassi; Kathleen Montpetit; Nathalie Gervais; Chantal Poulin; Marie-André Cantin; Thierry E. Benaroch

2002-01-01

443

Cortical, but Not Posterior Subcapsular, Cataract Shows Significant Familial  

E-print Network

cataract surgery1 and the most common form of cataract in clinical surgical series.2 Cortical cataractCortical, but Not Posterior Subcapsular, Cataract Shows Significant Familial Aggregation Wojciechowski, OD, MPH, Sheila K. West, PhD Purpose: To quantify the risk for age-related cortical cataract

Broman, Karl W.

444

Reversible posterior leucoencephalopathy syndrome in systemic lupus and vasculitis  

Microsoft Academic Search

OBJECTIVESReversible posterior leucoencephalopathy syndrome (RPLS) may develop in patients with renal insufficiency, hypertension, and immunosuppression, and is managed by prompt antihypertensive and anticonvulsant treatment. Four patients with renal insufficiency and fluid overload associated with Wegener's granulomatosis (one patient) and systemic lupus erythematosus (SLE) (three patients) are described, whose clinical picture and neuroimaging indicated RPLS.CASE REPORTSAll patients had headache, seizures, visual

A Primavera; D Audenino; N Mavilio; L Cocito

2001-01-01

445

Posterior communicating artery section during surgery for basilar tip aneurysm  

Microsoft Academic Search

Summary Although dividing the posterior communicating artery (PComA) during surgery has been criticized for increasing the risk of ischaemia, this procedure increases working space improving visibility and the ability to manipulate during treatment of basilar tip aneurysms via the pterional approach. We divided a hypoplastic PComA in 4 of our cases of basilar tip aneurysm. This was necessary because either

S. Inao; H. Kuchiwaki; N. Hirai; T. Gonda; M. Furuse

1996-01-01

446

Immunohistochemical analysis of mechanoreceptors in the human posterior cruciate ligament  

Microsoft Academic Search

Although long-term studies report successful results with total knee arthroplasty (TKA), performed with or without posterior cruciate ligament (PCL) retention, controversy exists as to which is preferable in regard to patient outcome and satisfaction. The possible proprioceptive role of the PCL may account for a more normal feeling of the arthroplasty. Although the PCL has been examined using various histological

M. E. Del Valle; S. F. Harwin; A. Maestro; A. Murcia; J. A. Vega

1998-01-01

447

Vertical and torsional VOR in posterior canal occlusion.  

PubMed

The vertical and torsional vestibulo-ocular reflexes (VOR) were investigated in 3 patients with surgical occlusion of the posterior semicircular canal and 1 patient with singular neurectomy, for treatment of refractory paroxysmal positional vertigo. Stimuli comprised sinusoidal oscillation in the coronal ("roll") and sagittal ("pitch") plane as well as in two oblique planes intermediate between pitch in order to stimulate left anterior + right posterior (LARP) and right anterior + left posterior (RALP) canal pairs separately. One case with left side BPPV was investigated pre and post-operatively. Depression of the vertical and torsional VOR gain was seen 1 week postoperatively when the occluded canal was placed in the optimal plane for stimulation at 1 week postoperatively and subsequently gradually recovered. Recordings in other planes suggested that the contralateral posterior canal was also hypofunctioning, a finding which may explain some residual gait unsteadiness in this case. The other 3 cases who were investigated postoperatively all showed a decrease in downward VOR gain in the "on' direction of the operated canal. The data indicate the specificity of the test procedure and underline the prognostic value of comprehensive pre-operative vestibular assessment. PMID:8749162

Kanayama, R; Bronstein, A M; Gresty, M A; Brookes, G B

1995-01-01

448

On quantum vs. classical probability  

NASA Astrophysics Data System (ADS)

Quantum theory shares with classical probability theory many important properties. I show that this common core regards at least the following six areas, and I provide details on each of these: the logic of propositions, symmetry, probabilities, composition of systems, state preparation and reductionism. The essential distinction between classical and quantum theory, on the other hand, is shown to be joint decidability versus smoothness; for the latter in particular I supply ample explanation and motivation. Finally, I argue that beyond quantum theory there are no other generalisations of classical probability theory that are relevant to physics.

Rau, Jochen

2009-12-01

449

On quantum vs. classical probability  

SciTech Connect

Quantum theory shares with classical probability theory many important properties. I show that this common core regards at least the following six areas, and I provide details on each of these: the logic of propositions, symmetry, probabilities, composition of systems, state preparation and reductionism. The essential distinction between classical and quantum theory, on the other hand, is shown to be joint decidability versus smoothness; for the latter in particular I supply ample explanation and motivation. Finally, I argue that beyond quantum theory there are no other generalisations of classical probability theory that are relevant to physics.

Rau, Jochen [Institut fuer Theoretische Physik, Johann Wolfgang Goethe-Universitaet, Max-von-Laue-Str. 1, 60438 Frankfurt am Main (Germany)], E-mail: jochen.rau@q-info.org

2009-12-15

450

Introduction to Probability and Statistics  

NSDL National Science Digital Library

Published by MIT and created by Professor Dmitry Panchenko for the Spring semester of 2005, this online course provides an introduction to probability and statistics for undergraduate students. The topics included are "basic probability models; combinatorics; random variables; discrete and continuous probability distributions; statistical estimation and testing; confidence intervals; and an introduction to linear regression." All lecture notes, assignments, and exams are available as PDF files. This is a fantastic and free way for educators and students to harness the quality education of MIT and bring it into their own classrooms.

Panchenko, Dmitry

451

Axial Spondylectomy and Circumferential Reconstruction via a Posterior Approach  

PubMed Central

Background Spinal metastases of the second cervical vertebra are a subset of tumors that is particularly difficult to address surgically. Previously described techniques require highly morbid circumferential dissection posterior to the pharynx for resection and reconstruction. Objective To perform a biomechanical analysis of instrumented reconstruction configurations used after axial spondylectomy and demonstrate safe use of a novel construct in a patient case report. Methods Several different published and novel reconstruction configurations were inserted into 7 occipitocervical spines that underwent axial spondylectomy. A biomechanical analysis of the constructs’ stiffness in flexion and extension, lateral bending, and rotation was performed. A patient then underwent a posterior-only approach for axial spondylectomy and circumferential reconstruction. Results Biomechanical analysis of different constructs demonstrated that anterior column reconstruction with bilateral cages spanning C1 lateral mass to C3 facet in combination with occipitocervical instrumentation was superior in flexion-extension and equivalent in lateral bending and rotation to currently used constructs. In the patient in which this construct was placed via a posterior-only approach for axial spondylectomy and instrumentation, the patient remained at neurological baseline and demonstrated no recurrence of local disease or failure of instrumentation to date. Conclusion When comparing C1 lateral mass to C3 facet bilateral cage plus occipitocervical instrumentation to existing anterior and posterior constructs, this novel reconstruction is biomechanically equivalent if not superior in performance. In a patient, the posterior-only approach for C2 spondylectomy with the novel reconstruction was safe, durable, and avoided the morbidity of the anterior approach. PMID:23149951

Jandial, Rahul; Kelly, Brandon; Bucklen, Brandon; Khalil, Saif; Chen, Mike Y.

2013-01-01

452

Anterior and posterior corneal stroma elasticity assessed using nanoindentation  

PubMed Central

Corneal biomechanics is an essential parameter for developing diagnostic and treatment methods of corneal-related diseases. It is widely accepted that corneal mechanical strength stems from the stroma's collagenous composition. However, more comprehensive insight into the mechanical properties within the stroma is needed to improve current corneal diagnostic and treatment techniques. The purpose of this study was to perform elasticity characterization of anterior and posterior stromal regions of human corneas using atomic force microscopy (AFM). Nine pairs of human whole globes were placed in 20% Dextran solution, cornea side down, to restore the corneal thickness to physiological levels (400-600?m). The epithelium and Bowman's membrane were removed from all eyes. Anterior stromal AFM elasticity testing was then performed on left (OS) eyes. Additional stroma was removed from right (OD) eyes to allow posterior stromal measurements at a depth of 50% of the original thickness. All experiments were performed with corneas submerged in 15% Dextran to maintain corneal hydration. The results of the study showed that the Young's modulus of elasticity of the anterior stroma (average: 281 ± 214kPa; range: 59-764kPa) was significantly higher than that of the posterior stroma (average: 89.5 ± 46.1kPa; range: 29-179kPa) (p=0.014). In addition, a linear relationship was found between the posterior stromal elasticity and anterior stromal elasticity (p=0.0428). On average, the elasticity of the posterior stroma is 39.3% of the anterior stroma. In summary, there appears to be an elasticity gradient within the corneal stroma, which should be considered in the design and development of corneal diagnostic and treatment methods to enhance efficacy. PMID:23800511

Dias, Janice; Ziebarth, Noël M.

2013-01-01

453

Cranioectodermal dysplasia: a probable ciliopathy.  

PubMed

Cranioectodermal dysplasia (CED), also known as Sensenbrenner syndrome, is a rare autosomal recessive genetic disorder characterized by typical craniofacial, skeletal and ectodermal defects, and tubulointerstitial nephritis leading to early end-stage renal failure. We report on a new familial case of a 9-year-old patient and two fetuses of 23 and 19 weeks of gestation respectively. Hypohidrosis was an additional ectodermal finding is the patient with CED. Postmortem findings in the two fetuses included acromesomelic shortening, craniofacial characteristics with absence of craniosynostosis, small kidneys with tubular and glomerular microscopic cysts, persistent ductal plate with portal fibrosis in the liver, small adrenals and roughly unremarkable histopathology of the physeal growth plate. Posterior fossa anomalies were additional findings in this patient and included an enlarged cisterna magna and a posterior fossa cyst. The above findings, in association with renal cysts, persistent ductal plate and portal fibrosis, introduce CED, a nonlethal genetic skeletal disorder of yet unknown molecular origin, as a possible member of the expanding group of ciliopathies. PMID:19760621

Konstantinidou, Anastasia E; Fryssira, Helen; Sifakis, Stavros; Karadimas, Charalampos; Kaminopetros, Petros; Agrogiannis, Georgios; Velonis, Stylianos; Nikkels, Peter G J; Patsouris, Efstratios

2009-10-01

454

Outage probability at finite SNR  

E-print Network

In this thesis, we present a technique to reduce the outage probability of a single user multiple input multiple output (MIMO) channel when a sub-optimal transceiver architecture is used. We show that in slow-fading ...

Akçaba, Cemal

2004-01-01

455

VESPA: False positive probabilities calculator  

NASA Astrophysics Data System (ADS)

Validation of Exoplanet Signals using a Probabilistic Algorithm (VESPA) calculates false positive probabilities and statistically validates transiting exoplanets. Written in Python, it uses isochrones [ascl:1503.010] and the package simpledist.

Morton, Timothy D.

2015-03-01

456

The Probabilities of Unique Events  

PubMed Central

Many theorists argue that the probabilities of unique events, even real possibilities such as President Obama's re-election, are meaningless. As a consequence, psychologists have seldom investigated them. We propose a new theory (implemented in a computer program) in which such estimates depend on an intuitive non-numerical system capable only of simple procedures, and a deliberative system that maps intuitions into numbers. The theory predicts that estimates of the probabilities of conjunctions should often tend to split the difference between the probabilities of the two conjuncts. We report two experiments showing that individuals commit such violations of the probability calculus, and corroborating other predictions of the theory, e.g., individuals err in the same way even when they make non-numerical verbal estimates, such as that an event is highly improbable. PMID:23056224

Khemlani, Sangeet S.; Lotstein, Max; Johnson-Laird, Phil

2012-01-01

457

Probability and Statistics Object Library  

NSDL National Science Digital Library

This library contains a plethora of downloadable applets and the components of the applets for use by teachers and students of probability and statistics. These objects (both executable files and source code) can be downloaded, modified if desired, and reused.

Siegrist, Kyle

458

Impact probability calculations --- comparison of methods  

NASA Astrophysics Data System (ADS)

We compare three different methods of statistical impact-probability calculations: our Hill sphere method that uses a super-sizing of the planet's collisional cross-section, the numerical averaging of Wetherill's (1967) formula, and the novel MOID method developed by us. The first and third are Monte Carlo simulations methods. In the first we count the number of Hill sphere passages for a large, random sample of orbits. In the third we search for orbits with MOID less than the collisional radius in a similar sample, calculating the MOID by the method of Wi?niowski and Rickman (2013), after which we compute the encounter timing range leading to collision for each selected object and compare with the target's orbital period. Our extensive comparisons use a constant semi-major axis of 3.5 au for the projectiles, and we focus on the parametric plane of perihelion distance and inclination. They show an excellent agreement among all the methods under practically all circumstances. However, in the vicinity of the singularities appearing in the Wetherill formulae (zero relative inclination, and equal perihelion distances) we find that only the MOID method yields accurate results. Due to the approximations inherent in the other methods, the super-sizing method underestimates the impact probability, and the Wetherill averaging overestimates it. This work was supported by the Polish National Science Center under Grant No. 2011/01/B/ST9/05442.

Rickman, H.; Wi?niowski, T.; Wajer, P.; Gabryszewski, R.; Valsecchi, G.

2014-07-01

459

Logical, conditional, and classical probability  

E-print Network

The propositional logic is generalized on the real numbers field. the logical function with all properties of the classical probability function is obtained. The logical analog of the Bernoulli independent tests scheme is constructed. The logical analog of the Large Number Law is deduced from properties of these functions. The logical analog of thd conditional probability is defined. Consistency encured by a model on a suitable variant of the nonstandard analysis.

G. A. Quznetsov

2005-05-20

460

Joint probabilities and quantum cognition  

SciTech Connect

In this paper we discuss the existence of joint probability distributions for quantumlike response computations in the brain. We do so by focusing on a contextual neural-oscillator model shown to reproduce the main features of behavioral stimulus-response theory. We then exhibit a simple example of contextual random variables not having a joint probability distribution, and describe how such variables can be obtained from neural oscillators, but not from a quantum observable algebra.

Acacio de Barros, J. [Liberal Studies, 1600 Holloway Ave., San Francisco State University, San Francisco, CA 94132 (United States)

2012-12-18

461

Analytic bounds on transmission probabilities  

SciTech Connect

We develop some new analytic bounds on transmission probabilities (and the related reflection probabilities and Bogoliubov coefficients) for generic one-dimensional scattering problems. To do so we rewrite the Schroedinger equation for some complicated potential whose properties we are trying to investigate in terms of some simpler potential whose properties are assumed known, plus a (possibly large) 'shift' in the potential. Doing so permits us to extract considerable useful information without having to exactly solve the full scattering problem.

Boonserm, Petarpa, E-mail: petarpa.boonserm@gmail.co [Department of Mathematics, Faculty of Science Chulalongkorn University, Phayathai Rd., Pathumwan Bangkok 10330 (Thailand); Visser, Matt, E-mail: matt.visser@msor.vuw.ac.n [School of Mathematics, Statistics, and Operations Research, Victoria University of Wellington (New Zealand)

2010-07-15

462

Evaluation of microbial release probabilities  

NASA Technical Reports Server (NTRS)

Work undertaken to improve the estimation of the probability of release of microorganisms from unmanned Martian landing spacecraft is summarized. An analytical model is described for the development of numerical values for release parameters and release mechanisms applicable to flight missions are defined. Laboratory test data are used to evolve parameter values for use by flight projects in estimating numerical values for release probabilities. The analysis treats microbial burden located on spacecraft surfaces, between mated surfaces, and encapsulated within materials.

1972-01-01

463

Pretty Purple Probabilities and Data Analysis!  

NSDL National Science Digital Library

Plump Probability Problems need Played! The probability of the cards while playing the Probability Game! Find the probability of landing on each color, changing the parts size, when you spin the Probability Spinner! If you want a definition of any probability term.. click the word Definition ...

Ms. Nieman

2007-11-22

464

On classical finite probability theory as a quantum probability calculus  

E-print Network

This paper shows how the classical finite probability theory (with equiprobable outcomes) can be reinterpreted and recast as the quantum probability calculus of a pedagogical or "toy" model of quantum mechanics over sets (QM/sets). There have been four previous attempts to develop a quantum-like model with the base field of $\\mathbb{C}$ replaced by $\\mathbb{Z}_{2}$, but they are all forced into a merely "modal" interpretation by requiring the brackets to take values in $\\mathbb{Z}_{2}$ (1 = possible, 0 = impossible). But the usual QM brackets give the "overlap" between states {\\psi} and {\\phi}, so for subsets S,T of U, the natural definition is $=|S{\\cap}T|$. This allows QM/sets to be developed with a full probability calculus that turns out to be the perfectly classical Laplace-Boole finite probability theory. The point is not to clarify finite probability theory but to elucidate quantum mechanics itself by seeing some of its quantum features (e.g., two-slit experiment) in a classical setting.

David Ellerman

2015-02-03

465

What you need to know about ossification of the posterior longitudinal ligament to optimize cervical spine surgery: A review  

PubMed Central

What are the risks, benefits, alternatives, and pitfalls for operating on cervical ossification of the posterior longitudinal ligament (OPLL)? To successfully diagnose OPLL, it is important to obtain Magnetic Resonance Images (MR). These studies, particularly the T2 weighted images, provide the best soft-tissue documentation of cord/root compression and intrinsic cord abnormalities (e.g. edema vs. myelomalacia) on sagittal, axial, and coronal views. Obtaining Computed Tomographic (CT) scans is also critical as they best demonstrate early OPLL, or hypertrophied posterior longitudinal ligament (HPLL: hypo-isodense with punctate ossification) or classic (frankly ossified) OPLL (hyperdense). Furthermore, CT scans reveal the “single layer” and “double layer” signs indicative of OPLL penetrating the dura. Documenting the full extent of OPLL with both MR and CT dictates whether anterior, posterior, or circumferential surgery is warranted. An adequate cervical lordosis allows for posterior cervical approaches (e.g. lamionplasty, laminectomy/fusion), which may facilitate addressing multiple levels while avoiding the risks of anterior procedures. However, without lordosis and with significant kyphosis, anterior surgery may be indicated. Rarely, this requires single/multilevel anterior cervical diskectomy/fusion (ACDF), as this approach typically fails to address retrovertebral OPLL; single or multilevel corpectomies are usually warranted. In short, successful OPLL surgery relies on careful patient selection (e.g. assess comorbidities), accurate MR/CT documentation of OPLL, and limiting the pros, cons, and complications of these complex procedures by choosing the optimal surgical approach. Performing OPLL surgery requires stringent anesthetic (awake intubation/positioning) and also the following intraoperative monitoring protocols: Somatosensory evoked potentials (SSEP), motor evoked potentials (MEP), and electromyography (EMG). PMID:24843819

Epstein, Nancy E.

2014-01-01

466

Accurate floating point summation James Demmel  

E-print Network

Accurate floating point summation James Demmel Yozo Hida May 8, 2002 Abstract We present and analyze several simple algorithms for accurately summing n floating point numbers S = n i=1 si precision only (F 2f). We apply this result to the floating point formats in the (proposed revision of the

California at Berkeley, University of

467

Accurate Structural Correlations from Maximum Likelihood Superpositions  

Microsoft Academic Search

The cores of globular proteins are densely packed, resulting in complicated networks of structural interactions. These interactions in turn give rise to dynamic structural correlations over a wide range of time scales. Accurate analysis of these complex correlations is crucial for understanding biomolecular mechanisms and for relating structure to function. Here we report a highly accurate technique for inferring the

Douglas L. Theobald; Deborah S. Wuttke

2008-01-01

468

Posterior distributions of a statistic of propagation loss inferred from radar sea clutter  

E-print Network

Posterior distributions of a statistic of propagation loss inferred from radar sea clutter L. Ted), Posterior distributions of a statistic of propagation loss inferred from radar sea clutter, Radio Sci., 40

Buckingham, Michael

469

21 CFR 872.3900 - Posterior artificial tooth with a metal insert.  

Code of Federal Regulations, 2014 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3900 Posterior artificial tooth with a metal insert. (a) Identification. A posterior...

2014-04-01

470

Efficient Exploration of Multi-Modal Posterior Distributions  

E-print Network

The Markov Chain Monte Carlo (MCMC) algorithm is a widely recognised as an efficient method for sampling a specified posterior distribution. However, when the posterior is multi-modal, conventional MCMC algorithms either tend to become stuck in one local mode, become non-Markovian or require an excessively long time to explore the global properties of the distribution. We propose a novel variant of MCMC, mixed MCMC, which exploits a specially designed proposal density to allow the generation candidate points from any of a number of different modes. This new method is efficient by design, and is strictly Markovian. We present our method and apply it to a toy model inference problem to demonstrate its validity.

Hu, Yi-Ming; Heng, Ik Siong

2014-01-01

471

Extended indications for robotic surgery for posterior mediastinal tumors.  

PubMed

Previously, we evaluated use of the da Vinci Surgical System for anterior and middle mediastinal tumors in clinical cases, focusing on feasibility, safety, and appropriate settings. In this study, we evaluated extending the indications for robotic surgical treatment of posterior mediastinal tumors to include those located adjacent to the upper vertebrae or aorta. Three patients with mediastinal tumors located immediately adjacent to the vertebrae or aorta, underwent resection with the da Vinci Surgical System. All resected tumors were benign histologically. Robotic surgery enabled treatment of tumors located in the posterior mediastinum, which are very difficult to reach, making resection with the conventional video-assisted thoracoscopic surgery technique extremely difficult. All procedures were performed safely, smoothly, and extremely precisely. Crucial to the success of these operations were the appropriate placement and angle of the special da Vinci surgical ports in relation to the target and the patient's position, which varied according to the tumor location. PMID:22718720

Kajiwara, Naohiro; Kakihana, Masatoshi; Usuda, Jitsuo; Ohira, Tatsuo; Kawate, Norihiko; Ikeda, Norihiko

2012-06-01

472

Posterior reversible encephalopathy syndrome in a adult female.  

PubMed

Posterior reversible encephalopathy syndrome is a clinico-neuroradiologic diagnosis, with rapidly evolving neurologic condition, characterized by headache, confusion, altered mental status, seizures, cortical blindness, lethargy, stupor, and occasionally, focal neurological signs accompanied by a typical computed tomography or magnetic resonance imaging pattern. With early recognition and treatment, complete resolution of symptoms occurs. Typical imaging findings characteristically involve the white matter bilaterally in the parieto-occipital regions. Atypical imaging finding of contrast enhancement of lesion can occur, but is less common. A 20-year-old primiparous lady presented with posterior reversible encephalopathy syndrome. To the best of our knowledge, this is the first documented case in Nigeria. This case-report highlights the importance of recognizing the salient imaging features in this lethal but reversible entity with prompt management. PMID:24923375

Oyinloye, O I; Adesiyun, O A M; Atobatele, M O; Fawole, A A

2014-01-01

473

Experimental posterior uveitis. I: A clinical, angiographic, and pathological study.  

PubMed Central

The clinical, angiographic, and histopathological features of experimental posterior uveitis in the black hooded Lister rat are described. This mild form of experimental allergic uveoretinitis (EAU) is induced by sensitisation with retinal S antigen in Freund's complete adjuvant, and the inflammation produced is confined to the posterior segment of the eye. This allows for the first time precise photographic and angiographic documentation of the evolution of clinical signs, because there is minimal clouding of the vitreous by inflammatory cells. Clinically the disease is characterised by the appearance of disc oedema and periphlebitis, followed by focal infiltrates in the deep retinal layers, with eventual atrophy of the pigment epithelium. Histologically, retinal vasculitis is associated with focal mononuclear cell infiltration and necrosis of the photoreceptor layers. This model closely resembles the clinical features of idiopathic retinal vasculitis seen in man. Images PMID:3651374

Stanford, M R; Brown, E C; Kasp, E; Graham, E M; Sanders, M D; Dumonde, D C

1987-01-01

474

Posterior Tibial Tendon Dysfunction: An Overlooked Cause of Foot Deformity  

PubMed Central

Posterior tibial tendon dysfunction is the most common cause of adult acquired flatfoot. Degenerative changes in this tendon, lead to pain and weakness and if not identified and treated will progress to deformity of the foot and degenerative changes in the surrounding joints. Patients will complain of medial foot pain, weakness, and a slowly progressive foot deformity. A “too many toes” sign may be present and patients will be unable to perform a single heal raise test. Investigations such X-ray, ultrasound and magnetic resonance imaging will help stage the disease and decide on management. The optimal manage may change based on the progression of deformity and stage of disease. Early identification and prompt initiation of treatment can halt progression of the disease. The purpose of this article is to examine the causes, signs, symptoms, examinations, investigations and treatment options for posterior tibial tendon dysfunction.

Bubra, Preet Singh; Keighley, Geffrey; Rateesh, Shruti; Carmody, David

2015-01-01

475

Delayed diagnosed posterior interosseous nerve palsy due to intramuscular myxoma  

PubMed Central

We present a case of posterior interosseous nerve palsy after bowel surgery associated with intramuscular myxoma of the supinator muscle. The initial symptoms of swelling of the forearm made it difficult to distinguish the condition from extravasations after intravenous cannulation. The diagnosis was finally established with nerve conduction studies and MRI 3?months after symptom onset. The patient underwent surgery for removal of the tumour and decompression of the posterior interosseous nerve. The histological examination identified the tumour as intramuscular myxoma and the patient made a full recovery with no recurrence of the lesion until present. Every swelling on the forearm causing neurological disorders is tumour suspected and should be examined clinically as well as electrophysically and radiographically. Early surgery and nerve decompression should follow immediately after the diagnosis. In case of intramuscular myxoma, good recovery of function after surgery with low recurrence risk may be expected. PMID:23576649

Kursumovic, A; Mattiassich, G; Rath, S

2013-01-01

476

Foraminotomia cervical posterior en el tratamiento de conflictos foraminales  

PubMed Central

Introducción: La foraminomotima cervical posterior es un procedimiento utilizado para la descompresion radicular por via posterior y constituye una alternativa a la via clásica anterior. En este trabajo evaluamos nuestra serie de pacientes tratados por esta via. Método: Desde enero de 2008 a diciembre de 2011, 17 pacientes (18 foraminotomías) fueron operados por presentar cervicobraquialgia a causa de un conflicto foraminal, realizando un foraminotomía cervical posterior. Los pacientes fueron evaluados en el postoperatorio inmediato, al mes y a los 3 meses de la cirugía. Los parámetros para valorar los resultados fueron la Escala Análoga del Dolor (VAS), la Neck Disability Index y los criterios de Odom. Resultados: El dolor radicular por conflicto foraminal secundario a hernia de disco cervical fue el síntoma y la patología predominante. El nivel más afectado fue C5-C6. La resolución completa del dolor radicular se observó en casi todos los pacientes. La VAS preoperatoria en promedio fue de 8.8 (mínimo 8 – máximo 10), con una franca mejoría en todos los casos (0.4 en el último control). La media en la Neck Disability Index al inicio fue de 35.3 (mínimo 32 – máximo 45), con una evolución favorable en la evaluación final (0.6). Los Criterios de Odom para la evaluación de pacientes operados de columna cervical fueron satisfactorios con un promedio de 1.17. Se observaron complicaciones en 4 pacientes (23%), todas tuvieron una evolución favorable. No hubo infecciones, discitis ni empeoramiento de los síntomas preexistentes en ningún paciente. Conclusión: La foraminotomía cervical posterior es un procedimiento efectivo para el tratamiento del dolor radicular en los conflictos foraminales PMID:23596556

Campero, Álvaro; Barrera, Ramiro; Ajler, Pablo

2012-01-01

477

Posterior cortical atrophy: variant of Alzheimer’s disease?  

Microsoft Academic Search

Nine patients with posterior cortical atrophy (PCA), a rare degenerative brain disease of unclear etiology and nosology, were followed over a mean time of 7.4 years. The mean age at onset was low (56.2 years). At onset, eight patients had visuo-spatial and eight had memory impairment. A minority showed early signs of occipital lobe involvement with visual agnosia or hemianopia.

Klaus Schmidtke; Michael Hüll; Jochen Talazko

2005-01-01

478

A case with cholinesterase inhibitor responsive asymmetric posterior cortical atrophy  

Microsoft Academic Search

A 55-year-old right-handed woman presented initially with mild amnestic and depressive episodes but slowly developed progressive neurobehavioral symptoms, indicative of posterior cortical atrophy in ensuing years. A more detailed neurobehavioral test suggested predominant right temporo-parietal dysfunction with executive functional deficits. SPECT and MRI findings revealed right unilateral temporo-parietal involvement. Cholinesterase inhibitor administration led to amelioration of symptoms. We suggest that

Eunhee Kim; Yunsoo Lee; Jongkeol Lee; Seol-Heui Han

2005-01-01

479

Novel Drug Delivery Systems for Posterior Segment Ocular Disease  

Microsoft Academic Search

Delivery of drugs to the eye, particularly for the treatment of posterior segment diseases, is a challenging task that requires\\u000a drug transport across barriers in the eye, which are present for the purpose of limiting the entry of drugs and xenobiotics.\\u000a The common methods of drug delivery to the eye—eyedrops, direct injection, and systemic administration—all have problems that\\u000a limit their

Heather Sheardown; W. Mark Saltzman

480

Standard versus high-flexion posterior stabilized total knee prostheses.  

PubMed

This meta-analysis compared clinical outcomes between standard and high-flexion posterior-stabilized total knee prostheses to evaluate which type of total knee prosthesis was superior. Randomized, controlled trials published until October 2013 comparing standard and high-flexion posterior-stabilized total knee prostheses were reviewed. Methodologic quality was assessed with the Physiotherapy Evidence Database scale. After data extraction, the authors compared results with fixed effects or random effects models, depending on the heterogeneity of the included studies. Eight randomized, controlled trials involving 660 patients met the predetermined inclusion criteria. No statistically significant differences between patients undergoing standard and high-flexion posterior-stabilized total knee prostheses were noted in postoperative range of motion (ROM) (weighted mean difference, -1.43; 95% confidence interval [CI], -4.52 to 1.67; P=.37); flexion angle (weighted mean difference, 0.54; 95% CI, -3.75 to 4.84; P=.80); Knee Society Score (weighted mean difference, 0.92; 95% CI, -0.64 to 2.48; P=.25); Hospital for Special Surgery knee score (weighted mean difference, 0.57; 95% CI, -0.42 to 1.55; P=.26); or Knee Society function score (weighted mean difference, 1.00; 95% CI, -1.49 to 3.49; P=.43). No statistical difference was found between the 2 prosthesis types in complications, involving 21 cases in the standard group and 14 cases in the high-flexion group. The current findings confirm that high-flexion posterior-stabilized total knee prostheses are not superior to standard prostheses in terms of ROM, flexion angle, knee scores, or complications with 5 years or less of follow-up. [Orthopedics. 2015; 38(3):e206-e212.]. PMID:25760508

Li, Ning; Li, Junwei; Li, Peng; Wang, Dan; Liu, Ming; Xia, Lei

2015-03-01

481

Long-standing prion dementia manifesting as posterior cortical atrophy.  

PubMed

Prion diseases commonly manifest with the phenotype of subacute myoclonic encephalopathy. However, genetic forms of prion disease may have prolonged evolution mimicking neurodegenerative disease. We present the clinical and neuropathological features of a family with an early and long-standing dementia manifesting with posterior cortical atrophy and related to a 120 bp insertional mutation of the prion protein gene. Two cases exhibited mixed prion and A? pathology. The differential diagnosis with Alzheimer disease is discussed. PMID:21959360

Depaz, Raphaël; Haik, Stéphane; Peoc'h, Katell; Seilhean, Danielle; Grabli, David; Vicart, Savine; Sarazin, Marie; DeToffol, Bertrand; Remy, Catherine; Fallet-Bianco, Catherine; Laplanche, J L; Fontaine, Bertrand; Brandel, Jean Philippe

2012-01-01

482

Neurophysiological monitoring of cranial nerves during posterior fossa surgery.  

PubMed

Intraoperative neurophysiological monitoring of cranial nerve functions in surgery for microvascular decompression and tumors of the posterior fossa is important for minimizing risk of permanent damage to the nerves. In particular, intraoperative BAEP and the EMG function of muscle innervated by trigeminal and facial muscle have been found useful. We report here our experiences with intraoperative monitoring of brainstem auditory evoked potentials (BAEP) and EMG recorded from muscles supplied by the trigeminal and facial nerves. PMID:8748580

Broggi, G; Scaioli, V; Brock, S; Dones, I

1995-01-01

483

Posterior approach for sciatic aneurysm repair - technical note.  

PubMed

Aneurysm of the persistent sciatic artery is a rare cause of limb ischemia, which is a challenge for both diagnosis and treatment. After successful diagnosis adequate treatment may require skills in open and endovascular surgery. We present a patient with the aneurysm of the persistent sciatic artery treated by bypass procedure with PTFE graft using posterior approach. We named this procedure "dorsal bypass". Detailed explanation of clinical presentation, diagnosis and the surgical procedure is given in this paper. PMID:24003007

Cvetkovic, S; Koncar, I; Dragas, M; Ilic, N; Pejkic, S; Kostic, D; Davidovic, L

2014-10-01

484

Early treatment of posterior crossbite - a randomised clinical trial  

PubMed Central

Background The aim of this randomised clinical trial was to assess the effect of early orthodontic treatment in contrast to normal growth effects for functional unilateral posterior crossbite in the late deciduous and early mixed dentition by means of three-dimensional digital model analysis. Methods This randomised clinical trial was assessed to analyse the orthodontic treatment effects for patients with functional unilateral posterior crossbite in the late deciduous and early mixed dentition using a two-step procedure: initial maxillary expansion followed by a U-bow activator therapy. In the treatment group 31 patients and in the control group 35 patients with a mean age of 7.3 years (SD 2.1) were monitored. The time between the initial assessment (T1) and the follow-up (T2) was one year. The orthodontic analysis was done by a three-dimensional digital model analysis. Using the ‘Digimodel’ software, the orthodontic measurements in the maxilla and mandible and for the midline deviation, the overjet and overbite were recorded. Results Significant differences between the control and the therapy group at T2 were detected for the anterior, median and posterior transversal dimensions of the maxilla, the palatal depth, the palatal base arch length, the maxillary arch length and inclination, the midline deviation, the overjet and the overbite. Conclusions Orthodontic treatment of a functional unilateral posterior crossbite with a bonded maxillary expansion device followed by U-bow activator therapy in the late deciduous and early mixed dentition is an effective therapeutic method, as evidenced by the results of this RCT. It leads to three-dimensional therapeutically induced maxillary growth effects. Dental occlusion is significantly improved, and the prognosis for normal craniofacial growth is enhanced. Trial registration Registration trial DRKS00003497 on DRKS PMID:23339736

2013-01-01

485

Spontaneous relapsing and recurring large multiloculated posterior fossa enteric cyst  

Microsoft Academic Search

Summary  Intracranial enterogenous cyst is an uncommon entity. We report a case of enterogenous cyst of the posterior fossa situated\\u000a posterolateral to the brain stem and extending into the left CP angle cistern. Patient had spontaneous regression and recurrence\\u000a of the cyst. Clinical features and radiological findings are described. Near total excision of the cyst was carried out through\\u000a the retro

S. Vaishya; T. Ramesh

2006-01-01

486

Echocardiographic Manifestation of Esophagitis Mimicking a Posterior Mediastinal Mass  

PubMed Central

Incidental extracardiac findings (ECFs) are commonly noted on cardiac imaging. The majority of the ECFs are noticed on computed tomography (CT), cardiac magnetic resonance scanning, and myocardial perfusion imaging. Although transthoracic echocardiography (TTE) is a widely used cardiac modality, there is scarcity of data describing ECF on TTE. ECFs have the potential to alter patient management. We present a rare case of a cystic mass seen in the posterior mediastinum on TTE, which led to further evaluation and diagnosis of esophagitis with ulceration.

Swarup, Supreeya; Kantamneni, Sowmya; Kabir, Sarah; Zeltser, Roman; Makaryus, Amgad N

2014-01-01

487

Posterior Reversible Encephalopathy Syndrome Associated with FOLFOX Chemotherapy  

PubMed Central

Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiologic entity characterized by headaches, altered mental status, seizures, visual loss, and characteristic imaging pattern in brain MRI. The cause of PRES is not yet understood. We report a case of a 27-year-old woman that developed PRES after the use of FOLFOX 5 (oxaliplatin/5-Fluoracil/Leucovorin) chemotherapy for a colorectal cancer. PMID:23533871

Porcello Marrone, Luiz Carlos; Marrone, Bianca Fontana; Pascoal, Tharick Ali; Schilling, Lucas Porcello; Soder, Ricardo Bernardi; Ferreira, Sheila Schuch; Gadonski, Giovani; da Costa, Jaderson Costa

2013-01-01

488

Fistula of the Posterior Communicating Artery and Cavernous Sinus  

Microsoft Academic Search

Summary: A 24-year-old man was admitted with conjunctival hyperemia of the left eye and progressive chemosis and propto- sis 1 month after a head injury. An angiogram showed an arte- rial-cavernous sinus fistula of the posterior communicating artery, which was treated with minicoils. The atypical configura- tion, transvenous embolization, and unusual nature of the com- munication suggested that communication developed

Kazushi Kinugasa; Hisato Higashi; Takashi Ohmoto

489

Bilateral Circumscribed Posterior Keratoconus: Visualization by Ultrasound Biomicroscopy and Slit-Scanning Topography Analysis  

PubMed Central

This paper documents a rare nonprogressive developmental disorder—bilateral circumscribed posterior keratoconus—in a 60-year-old man referred for a cataract surgery. For the first time ultrasound biomicroscopy was used to visualise the local anterior bulging of the posterior corneal surface with concomitant thinning of the stroma. The amount of localized posterior depression, corneal thickness and the refractive power of both the posterior and anterior corneal curvature were measured using slit-scanning topography analysis (Orbscan). PMID:22496963

Rejdak, Robert; Nowomiejska, Katarzyna; Haszcz, Dariusz; Jünemann, Anselm G. M.

2012-01-01

490

Intensity-Modulated Arc Therapy for Pediatric Posterior Fossa Tumors  

SciTech Connect

Purpose: To compare intensity-modulated arc therapy (IMAT) to noncoplanar intensity-modulated radiation therapy (IMRT) in the treatment of pediatric posterior fossa tumors. Methods and Materials: Nine pediatric patients with posterior fossa tumors, mean age 9 years (range, 6-15 years), treated using IMRT were chosen for this comparative planning study because of their tumor location. Each patient's treatment was replanned to receive 54 Gy to the planning target volume (PTV) using five different methods: eight-field noncoplanar IMRT, single coplanar IMAT, double coplanar IMAT, single noncoplanar IMAT, and double noncoplanar IMAT. For each method, the dose to 95% of the PTV was held constant, and the doses to surrounding critical structures were minimized. The different plans were compared based on conformity, total linear accelerator dose monitor units, and dose to surrounding normal tissues, including the entire body, whole brain, temporal lobes, brainstem, and cochleae. Results: The doses to the target and critical structures for the various IMAT methods were not statistically different in comparison with the noncoplanar IMRT plan, with the following exceptions: the cochlear doses were higher and whole brain dose was lower for coplanar IMAT plans; the cochleae and temporal lobe doses were lower and conformity increased for noncoplanar IMAT plans. The advantage of the noncoplanar IMAT plan was enhanced by doubling the treatment arc. Conclusion: Noncoplanar IMAT results in superior treatment plans when compared to noncoplanar IMRT for the treatment of posterior fossa tumors. IMAT should be considered alongside IMRT when treatment of this site is indicated.

Beltran, Chris, E-mail: chris.beltran@stjude.org [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, TN (United States); Gray, Jonathan; Merchant, Thomas E. [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, TN (United States)

2012-02-01

491

Evidence for extra radiation? Profile likelihood versus Bayesian posterior  

SciTech Connect

A number of recent analyses of cosmological data have reported hints for the presence of extra radiation beyond the standard model expectation. In order to test the robustness of these claims under different methods of constructing parameter constraints, we perform a Bayesian posterior-based and a likelihood profile-based analysis of current data. We confirm the presence of a slight discrepancy between posterior- and profile-based constraints, with the marginalised posterior preferring higher values of the effective number of neutrino species N{sub eff}. This can be traced back to a volume effect occurring during the marginalisation process, and we demonstrate that the effect is related to the fact that cosmic microwave background (CMB) data constrain N{sub eff} only indirectly via the redshift of matter-radiation equality. Once present CMB data are combined with external information about, e.g., the Hubble parameter, the difference between the methods becomes small compared to the uncertainty of N{sub eff}. We conclude that the preference of precision cosmological data for excess radiation is 'real' and not an artifact of a specific choice of credible/confidence interval construction.

Hamann, Jan, E-mail: hamann@phys.au.dk [Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark)

2012-03-01

492

Evaluation of mandibular condyles in children with unilateral posterior crossbite.  

PubMed

The relationship of mandibular condyle dimensions and its association with unilateral posterior crossbite (UPXB) has been suggested in the literature. The purpose of this prospective study was to evaluate mandibular condyles on the left and right sides and between crossed and non-crossed sides in the sagittal and coronal planes, using cone-beam computed tomography (CBCT). Twenty CBCT images of 40 temporo mandibular joints (TMJs) in individuals in mixed dentition phase, which included 9 males (mean 7.9 years) and 11 females (mean 8.2 years), with unilateral posterior crossbite without premature contacts and functional mandibular shifts and with transverse maxillary deficiency. The criteria for sample exclusion included the presence of painful symptoms, facial trauma history, systemic diseases such as juvenile rheumatoid arthritis, mouth opening limitation (< 40 mm), congenital or genetic anomalies, and skeletal asymmetries that may result in TMJ disorders. Dimensional measurements of the condyles between the right and left sides and crossed and non-crossed sides in sagittal and coronal view were made. There was no significant difference between the measurements of the crossed and non-crossed sides in both sagittal and coronal view. These findings suggest that the presence of unilateral posterior crossbite in children with UPXB did not result in changes between the mandibular condyles in the right and left sides or between the crossed and non-crossed sides in the coronal or sagittal plane. PMID:25760067

Illipronti-Filho, Edson; Fantini, Solange Mongelli; Chilvarquer, Israel

2015-03-01

493

Effect of four different intraocular lenses on posterior capsule opacification  

PubMed Central

AIM To evaluate the impact of 4 different intraocular lenses (IOLs) on posterior capsule opacification (PCO) by comparing the neodymium: yttrium-aluminum-garnet (Nd:YAG) laser capsulotomy rates. METHODS This retrospective study included 4970 eyes of 4013 cataract patients who underwent phacoemulsification and IOL implantation between January 2000 and January 2008 by the same surgeon at one clinic. Four different IOLs were assessed. The outcome parameter was the incidence of Nd:YAG laser posterior capsulotomies. RESULTS An Nd:YAG laser posterior capsulotomy was performed in 153 (3.07%) of the 4970 eyes. The mean follow-up time was 84mo for all of the IOL groups. The percentage of eyes developing PCO was significantly greater for the acrylic hydrophilic IOLs than for the hydrophobic IOLs, although eyes with acrylic hydrophilic IOLs did not require Nd:YAG laser capsulotomy as soon as eyes with acrylic hydrophobic IOLs. There was no difference between the long-term PCO rates when 1- and 3-piece acrylic hydrophobic IOLs were compared or when IOLs made of the same material but with different haptic angles were compared. CONCLUSION In this study, eyes with acrylic hydrophilic IOLs were more likely to develop PCO than those with acrylic hydrophobic IOLs. The lens design (1-piece versus 3-piece and varying haptic angles) did not affect the PCO rate. PMID:25709920

Duman, Rahmi; Karel, Fatih; Özyol, Pelin; Ate?, Can

2015-01-01

494

Detonation probabilities of high explosives  

SciTech Connect

The probability of a high explosive violent reaction (HEVR) following various events is an extremely important aspect of estimating accident-sequence frequency for nuclear weapons dismantlement. In this paper, we describe the development of response curves for insults to PBX 9404, a conventional high-performance explosive used in US weapons. The insults during dismantlement include drops of high explosive (HE), strikes of tools and components on HE, and abrasion of the explosive. In the case of drops, we combine available test data on HEVRs and the results of flooring certification tests to estimate the HEVR probability. For other insults, it was necessary to use expert opinion. We describe the expert solicitation process and the methods used to consolidate the responses. The HEVR probabilities obtained from both approaches are compared.

Eisenhawer, S.W.; Bott, T.F.; Bement, T.R.

1995-07-01

495

Estimating Second Order Probability Beliefs from Subjective Survival Data  

PubMed Central

Based on subjective survival probability questions in the Health and Retirement Study (HRS), we use an econometric model to estimate the determinants of individual-level uncertainty about personal longevity. This model is built around the modal response hypothesis (MRH), a mathematical expression of the idea that survey responses of 0%, 50%, or 100% to probability questions indicate a high level of uncertainty about the relevant probability. We show that subjective survival expectations in 2002 line up very well with realized mortality of the HRS respondents between 2002 and 2010. We show that the MRH model performs better than typically used models in the literature of subjective probabilities. Our model gives more accurate estimates of low probability events and it is able to predict the unusually high fraction of focal 0%, 50%, and 100% answers observed in many data sets on subjective probabilities. We show that subjects place too much weight on parents’ age at death when forming expectations about their own longevity, whereas other covariates such as demographics, cognition, personality, subjective health, and health behavior are under weighted. We also find that less educated people, smokers, and women have less certain beliefs, and recent health shocks increase uncertainty about survival, too. PMID:24403866

Hudomiet, Péter; Willis, Robert J.

2013-01-01

496

Interference of probabilities in dynamics  

SciTech Connect

A new class of dynamical systems with a preset type of interference of probabilities is introduced. It is obtained from the extension of the Madelung equation by replacing the quantum potential with a specially selected feedback from the Liouville equation. It has been proved that these systems are different from both Newtonian and quantum systems, but they can be useful for modeling spontaneous collective novelty phenomena when emerging outputs are qualitatively different from the weighted sum of individual inputs. Formation of language and fast decision-making process as potential applications of the probability interference is discussed.

Zak, Michail, E-mail: michail.zak@gmail.com [Jet Propulsion Laboratory California Institute of Technology, Pasadena, CA 91109 (United States)

2014-08-15

497

Knowledge typology for imprecise probabilities.  

SciTech Connect

When characterizing the reliability of a complex system there are often gaps in the data available for specific subsystems or other factors influencing total system reliability. At Los Alamos National Laboratory we employ ethnographic methods to elicit expert knowledge when traditional data is scarce. Typically, we elicit expert knowledge in probabilistic terms. This paper will explore how we might approach elicitation if methods other than probability (i.e., Dempster-Shafer, or fuzzy sets) prove more useful for quantifying certain types of expert knowledge. Specifically, we will consider if experts have different types of knowledge that may be better characterized in ways other than standard probability theory.

Wilson, G. D. (Gregory D.); Zucker, L. J. (Lauren J.)

2002-01-01

498

A Posterior Approach for Microphone Array Based Speech Recognition , Ivan Himawan1,2  

E-print Network

A Posterior Approach for Microphone Array Based Speech Recognition Dong Wang1 , Ivan Himawan1 are unavail- able, or heterogeneous channels are used. We present a new posterior-based approach for microphone array speech recogni- tion. Instead of enhancing speech signals, we enhance posterior phone

Edinburgh, University of

499

Planar Cell Polarity Enables Posterior Localization of Nodal Cilia and Left-Right Axis Determination during  

E-print Network

Planar Cell Polarity Enables Posterior Localization of Nodal Cilia and Left-Right Axis gene expression. The leftward fluid flow is thought to result from the posterior tilt of the cilia, which protrude from near the posterior portion of each cell's apical surface. The cells, therefore

Quake, Stephen R.

500

Varying the prior 29 Appendix C. Quality of the posterior estimates from prior replacement  

E-print Network

Varying the prior 29 Appendix C. Quality of the posterior estimates from prior replacement replacement may out-perform prior-specific training in some aspects of the quality of the estimated posterior inverse problem in which sampling (rather than a neural network) is used to estimate a single posterior