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1

Children's understanding of posterior probability.  

PubMed

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, children's decisions under uncertainty (Study 1) and judgments about random outcomes (Study 2) are correctly affected by posterior information. From the same age, children correctly revise their decisions in situations in which they face a single, uncertain event, produced by an intentional agent (Study 3). The finding that young children have some understanding of posterior probability supports the theory of naive extensional reasoning, and contravenes some pessimistic views of probabilistic reasoning, in particular the evolutionary claim that the human mind cannot deal with single-case probability. PMID:17391661

Girotto, Vittorio; Gonzalez, Michel

2007-03-27

2

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

3

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

4

Probabilities of exoplanet signals from posterior samplings  

NASA Astrophysics Data System (ADS)

Aims: Estimating the marginal likelihoods is an essential feature of model selection in the Bayesian context. It is especially crucial to have good estimates when assessing the number of planets orbiting stars and different models explain the noisy data with different numbers of Keplerian signals. We introduce a simple method for approximating the marginal likelihoods in practice when a statistically representative sample from the parameter posterior density is available. Methods: We use our truncated posterior mixture estimate to receive accurate model probabilities for models with different numbers of Keplerian signals in radial velocity data. We test this estimate in simple scenarios to assess its accuracy and rate of convergence in practice when the corresponding estimates calculated using the deviance information criterion can be applied to obtain trustworthy model comparison results. As a test case, we determine the posterior probability of a planet orbiting HD 3651 given Lick and Keck radial velocity data. Results: The posterior mixture estimate appears to be a simple and an accurate way of calculating marginal integrals from posterior samples. We show that it can be used in practice to estimate the marginal integrals reliably, given a suitable selection of the parameter ?, which controls the estimate's accuracy and convergence rate. It is also more accurate than the one-block Metropolis-Hastings estimate, and can be used in any application because it is based on assumptions about neither the nature of the posterior density nor the amount of either data or parameters in the statistical model.

Tuomi, M.; Jones, H. R. A.

2012-08-01

5

Efficient search using posterior phone probability estimates  

Microsoft Academic Search

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 efficiency with minimal effect on accuracy. In particular, the search space is dramatically reduced by phone deactivation pruning where phones with a small local posterior probability are deactivated. This approach

Steve Renals; Mike Hochberg

1995-01-01

6

N Gram Posterior Probabilities for Statistical Machine Translation  

Microsoft Academic Search

Word posterior probabilities are a com- mon approach for confidence estimation in automatic speech recognition and ma- chine translation. We will generalize this idea and introduce n-gram posterior prob- abilities and show how these can be used to improve translation quality. Addition- ally, we will introduce a sentence length model based on posterior probabilities. We will show significant improvements on

Richard Zens; Hermann Ney

2006-01-01

7

Efficient search with posterior probability estimates in HMM-based speech recognition  

Microsoft Academic Search

In this paper we present the methods we developed to estimate posterior probabilities for HMM states in continuous and discrete HMM-based speech recognition systems and several ways to speed up decoding by using these posterior probability estimates. The proposed pruning techniques are state deactivation pruning (SDP), similar to an approach proposed for hybrid recognition systems, and a novel posteriori-based lookahead

Daniel Willett; Christoph Neukirchen; Gerhard Rigoll

1998-01-01

8

Posterior Probability Estimation Techniques Embedded in a Bayes Filter for Vibration-Based Terrain Classification  

Microsoft Academic Search

\\u000a Vibration signals acquired during robot traversal provide enough information to yield a reliable prediction of the current\\u000a terrain type. In a recent approach, we combined a history of terrain class estimates into a final prediction. We therefore\\u000a adopted a Bayes filter taking the posterior probability of each prediction into account. Posterior probability estimates,\\u000a however, were derived from support vector machines

Philippe Komma; Andreas Zell

9

Ab externo technique for accurate haptic placement of transscleral sutured posterior chamber intraocular lenses.  

PubMed

A modified technique is presented for transscleral suture fixation of posterior chamber intraocular lenses for aphakic correction in cases with inadequate capsular support. An ab externo approach for suture externalization is described that minimizes intraocular manipulation and facilitates accurate placement of haptics in the ciliary sulcus, thereby reducing the risk of lens tilt and decentration. This technique eliminates intraocular suture knots and reduces the amount of time the globe is open during surgery by creating two intraocular suture loops in preparation for posterior chamber intraocular lens placement before creating a limbal incision. PMID:17278542

Kulkarni, Kaushal; Zarbin, Marco; Del Priore, Lucian V; Tezel, Tongalp H

10

Making binary decisions based on the posterior probability distribution associated with tomographic reconstructions  

SciTech Connect

An optimal solution to the problem of making binary decisions about a local region of a reconstruction is provided by the Bayesian method. The decision is made on the basis of the ratio of the posterior probabilities for the two hypotheses. The full Bayesian procedure requires an integration of the posterior probability over all possible values of the image outside the local region being analyzed. In the present work, this full treatment is replaced by the maximum value of the posterior probability obtained when the exterior region is varied, but the interior is fixed at both hypothesized functional forms. A Monte Carlo procedure is employed to evaluate the usefulness of the technique in a signal-known-exactly detection task in a noisy four-view tomographic reconstruction situation. 27 refs., 2 figs., 1 tab.

Hanson, K.M.

1991-01-01

11

Estimation of posterior probabilities of consumer situational choices with neural network classifiers  

Microsoft Academic Search

This study shows how neural networks can be used to estimate the posterior probabilities in a consumer choice situation. We provide the theoretical basis for its use and illustrate the entire neural network modeling procedure with a situational choice data set from AT&T. Our findings supported the appropriateness of this application and clearly illustrate the nonlinear modeling capability of neural

Michael Y. Hu; Murali Shanker; Ming S. Hung

1999-01-01

12

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

13

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

14

MLIP: using multiple processors to compute the posterior probability of linkage  

PubMed Central

Background Localization of complex traits by genetic linkage analysis may involve exploration of a vast multidimensional parameter space. The posterior probability of linkage (PPL), a class of statistics for complex trait genetic mapping in humans, is designed to model the trait model complexity represented by the multidimensional parameter space in a mathematically rigorous fashion. However, the method requires the evaluation of integrals with no functional form, making it difficult to compute, and thus further test, develop and apply. This paper describes MLIP, a multiprocessor two-point genetic linkage analysis system that supports statistical calculations, such as the PPL, based on the full parameter space implicit in the linkage likelihood. Results The fundamental question we address here is whether the use of additional processors effectively reduces total computation time for a PPL calculation. We use a variety of data – both simulated and real – to explore the question "how close can we get?" to linear speedup. Empirical results of our study show that MLIP does significantly speed up two-point log-likelihood ratio calculations over a grid space of model parameters. Conclusion Observed performance of the program is dependent on characteristics of the data including granularity of the parameter grid space being explored and pedigree size and structure. While work continues to further optimize performance, the current version of the program can already be used to efficiently compute the PPL. Thanks to MLIP, full multidimensional genome scans are now routinely being completed at our centers with runtimes on the order of days, not months or years.

Govil, Manika; Segre, Alberto M; Vieland, Veronica J

2008-01-01

15

Preoperative Posterior Leaflet Angle Accurately Predicts Outcome After Restrictive Mitral Valve Annuloplasty for Ischemic Mitral Regurgitation  

Microsoft Academic Search

Background—Ischemic mitral regurgitation (MR) often persists after restrictive mitral valve annuloplasty, in which case it is associated with worse clinical outcomes. The goal of the present study was to determine whether persistence of MR and\\/or clinical outcome could be predicted from preoperative analysis of mitral valve configuration. Methods and Results—In 51 consecutive patients undergoing restrictive annuloplasty for ischemic MR, posterior

Julien Magne; Philippe Pibarot; François Dagenais; Zeineb Hachicha; Jean G. Dumesnil; Mario Sénéchal

2010-01-01

16

Probability  

NSDL National Science Digital Library

This is introduction into probability. This project allows students to explore with probability, the days following gives students a further look into probability. Today, you are going to experiment with probability. Go to the site An introduction into probability and read the first three sections, the last sections is the one with the picture of the coins. After you have read a little bit about probability, you now get to explore probability through some games. Start ...

Thompson, Ms.

2008-12-01

17

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.

2010-01-01

18

Bayesian sensitivity analysis for posterior probability inferences in landslide hazard modeling  

NASA Astrophysics Data System (ADS)

Landslides hazard modeling implies assumptions on prior conditional density functions of predisposing and triggering factors. The model uses beta distribution to calculate the prior and conditional probability density functions for landslides triggering factors. The landslides triggering factor is considered the soil water content. The model takes into consideration the seasonal changes in vegetation interception and runoff derived from Landsat satellite images (Landsat MSS, TM, ETM+). The satellite images were downloaded from http://earthexplorer.usgs.gov website with no regard to cloud cover. All the images were bulk processed for radiance and reflectance the LAI index for each image was extracted and used in the interception model and maximum likelihood algorithm was applied for vegetation delineation and classification, used in evapotranspiration model. The soil water content was modeled for a period of 30 years, starting in 1975 and ending in 2005, in the Breaza administrative area and Panatau administrative area, located in the Curvature Subcarpathians. For each landslide occurred in this time frame the modeled soil water content was retained and further statistical analysis were conducted

Cosmin Sandric, Ionut; Chitu, Zenaida

2013-04-01

19

Interpretation of laboratory tests using a programmable hand-held calculator: calculation of posterior probability and relative risk on the basis of prior probability and sensitivity, specificity and result of the test.  

PubMed

A program is presented for the Hewlett-Packard HP- 41C programmable hand-held calculator that calculates the posterior probability and relative risk of an event (e.g. a disease) on the basis of prior probability (prevalence) and sensitivity, specificity and result of the test. PMID:6370577

van de Merwe, J P

1984-01-01

20

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 ...

Banks, Ms.

2005-05-11

21

Simple, accurate formula for the average bit error probability of multiple-input multiple-output free-space optical links over negative exponential turbulence channels.  

PubMed

In this Letter we investigate the error performance of multiple-input multiple-output free-space optical communication systems employing intensity modulation/direct detection and operating over strong atmospheric turbulence channels. Atmospheric-induced strong turbulence fading is modeled using the negative exponential distribution. For the considered system, an approximate yet accurate analytical expression for the average bit error probability is derived and an efficient method for its numerical evaluation is proposed. Numerically evaluated and computer simulation results are further provided to demonstrate the validity of the proposed mathematical analysis. PMID:22859146

Peppas, Kostas P; Lazarakis, Fotis; Alexandridis, Antonis; Dangakis, Kostas

2012-08-01

22

Posterior knee pain  

PubMed Central

Posterior knee pain is a common patient complaint. There are broad differential diagnoses of posterior knee pain ranging from common causes such as injury to the musculotendinous structures to less common causes such as osteochondroma. A precise understanding of knee anatomy, the physical examination, and of the differential diagnosis is needed to accurately evaluate and treat posterior knee pain. This article provides a review of the anatomy and important aspects of the history and physical examination when evaluating posterior knee pain. It concludes by discussing the causes and management of posterior knee pain.

Perret, D.

2010-01-01

23

[Posterior cerebral encephalopathy].  

PubMed

Posterior reversible encephalopathy (PRE) is a recent syndrome characterized by headache, vomiting, seizures, visual loss, altered mental status with or without motor or sensitive deficit. Neuroimaging demonstrates symmetrical posterior cortical and subcortical lesions. The aetiology remains uncertain but vascular hypotheses is the most retained. We report a case of a 21 year old man with posterior cerebral encephalopathy, the toxic hypo these remains the most probable. PMID:15969236

Boughammoura-Bouatay, Amel; Chebel, Saber; Fitouri, Fitouri; Hizem, Yosr; Frih-Ayed, Mahbouba

2005-02-01

24

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

25

On probability matching priors  

Microsoft Academic Search

First order probability matching priors are priors for which Bayesian and frequentist inference, in the form of posterior quantiles, or condence intervals, agree to a second order of approximation. The present paper shows that the class of matching priors developed by Peers (1965) and Tibshirani (1989) are readily (and uniquely) implemented in a third order approximation to the posterior marginal

Ana-Maria Staicu; Nancy M. Reid

2008-01-01

26

A Posteriori Transit Probabilities  

NASA Astrophysics Data System (ADS)

Given the radial velocity (RV) detection of an unseen companion, it is often of interest to estimate the probability that the companion also transits the primary star. Typically, one assumes a uniform distribution for the cosine of the inclination angle i of the companion's orbit. This yields the familiar estimate for the prior transit probability of ˜R*, given the primary radius R* and orbital semimajor axis a, and assuming small companions and a circular orbit. However, the posterior transit probability depends not only on the prior probability distribution of i but also on the prior probability distribution of the companion mass Mc, given a measurement of the product of the two (the minimum mass Mcsin i) from an RV signal. In general, the posterior can be larger or smaller than the prior transit probability. We derive analytic expressions for the posterior transit probability assuming a power-law form for the distribution of true masses, d?/dMc?Mc?, for integer values -3?? ? 3. We show that for low transit probabilities, these probabilities reduce to a constant multiplicative factor f? of the corresponding prior transit probability, where f? in general depends on ? and an assumed upper limit on the true mass. The prior and posterior probabilities are equal for ?. The posterior transit probability is ˜1.5 times larger than the prior for ? = -3 and is ˜4/? times larger for ? = -2, but is less than the prior for ??0, and can be arbitrarily small for ? > 1. We also calculate the posterior transit probability in different mass regimes for two physically-motivated mass distributions of companions around Sun-like stars. We find that for Jupiter-mass planets, the posterior transit probability is roughly equal to the prior probability, whereas the posterior is likely higher for Super-Earths and Neptunes (10 M?-30 M?) and Super-Jupiters (MJup-10 MJup), owing to the predicted steep rise in the mass function toward smaller masses in these regimes. We therefore suggest that companions with minimum masses in these regimes might be better-than-expected targets for transit follow-up, and we identify promising targets from RV-detected planets in the literature. Finally, we consider the uncertainty in the transit probability arising from uncertainties in the input parameters, and the effect of ignoring the dependence of the transit probability on the true semimajor axis on i.

Stevens, Daniel J.; Gaudi, B. Scott

2013-08-01

27

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

28

Are Subjective Probabilities Probabilities.  

National Technical Information Service (NTIS)

The determination of subjective probability as degree of felt certainty is considered. A detailed analysis is given of the problem of changes in feelings of uncertainty, defined as revisions of opinion. It appears that people seem to program their behavio...

G. Dezeeuw W. A. Wagenaar

1973-01-01

29

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

30

Probability and radical behaviorism.  

PubMed

The concept of probability appears to be very important in the radical behaviorism of Skinner. Yet, it seems that this probability has not been accurately defined and is still ambiguous. I give a strict, relative frequency interpretation of probability and its applicability to the data from the science of behavior as supplied by cumulative records. Two examples of stochastic processes are given that may model the data from cumulative records that result under conditions of continuous reinforcement and extinction, respectively. PMID:22478114

Espinosa, J M

1992-01-01

31

Evidential Probability  

Microsoft Academic Search

\\u000a Rudolf Carnap (1962) distinguished between probability1, which concerns rational degrees of belief, and probability2, which concerns statistical regularities. Although he claimed that both notions of probability were crucial to scientific\\u000a inference, he practically ignored probability2 in the development of his systems of inductive logic. By contrast, evidential probability, developed by Henry Kyburg (1961)\\u000a and later by Kyburg and Choh Man

Rolf Haenni; Jan-Willem Romeijn; Gregory Wheeler; Jon Williamson

32

Exponential Probabilities  

NSDL National Science Digital Library

The applet, created by Virginia Tech's Department of Statistics, allows you see how probabilities are determined from the exponential distribution. The user determines the mean of the distribution and the limits of probability. Three different probability expressions are available. Click "Calculate" to see the pdf and the cdf. The probability is highlighted in green on the pdf. This is a nice reference tool for anyone studying statistics.

Anderson-Cook, C.; Robinson, T.; Dorai-Raj, S.

2009-01-21

33

Probability Models  

NSDL National Science Digital Library

This site, presented by the Department of Statistics at Yale University, gives an explanation, a definition and an example of probability models. Topics include components of probability models and the basic rules of probability. Overall, this is a great resource for any mathematics classroom studying statistics.

Lacey, Michelle

2008-12-26

34

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. ...

Cate, Ms.

2008-04-23

35

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

36

T Probabilities  

NSDL National Science Digital Library

The applet, created by Virginia Tech's Department of Statistics, allows you to see how the T distribution is related to the Standard Normal distribution by calculating probabilities. The T distribution is primarily used to make inferences on a Normal mean when the variance is unknown. If the variance is known inference on the mean can be done using the Standard Normal. The user has a choice of three different probability expressions, then can change the degrees of freedom and the limits of probability.

Anderson-Cook, C.; Robinson, T.; Dorai-Raj, S.

2009-09-18

37

Plinko Probability  

NSDL National Science Digital Library

This online game, modeled after the classic game of "Plinko" from "The Price is Right", requires students to determine the probability of an event in percent form prior to "earning" their Plinko chips. The speed with which they answer each of the ten probability questions determines how many chips they earn. Students then use their knowledge of probability and chance to place their chips and try to get the highest score.

Hui, T. L.

2011-01-01

38

Binomial Probabilities  

NSDL National Science Digital Library

The page will calculate the following: exact binomial probabilities, approximation via the normal distribution, approximation via the poisson distribution. This page will calculate and/or estimate binomial probabilities for situations of the general "k out of n" type, where k is the number of times a binomial outcome is observed or stipulated to occur, p is the probability that the outcome will occur on any particular occasion, q is the complementary probability (1-p) that the outcome will not occur on any particular occasion, and n is the number of occasions.

Lowry, Richard

2009-11-05

39

Posterior Cervical Bone Screws  

Center for Biologics Evaluation and Research (CBER)

Text Version... Smith MD et al, Spine 1993: 18, 1984. Page 3. POSTERIOR CERVICAL BONE SCREWS ... Page 4. POSTERIOR CERVICAL BONE SCREWS ... More results from www.fda.gov/downloads/advisorycommittees/committeesmeetingmaterials

40

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

2008-12-23

41

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.

2009-01-08

42

Improved Log(gf) Values for Lines of Ti I and Abundance Determinations in the Photospheres of the Sun and Metal-Poor Star HD 84937 (Accurate Transition Probabilities for Ti I)  

NASA Astrophysics Data System (ADS)

New atomic transition probability measurements for 948 lines of Ti I are reported. Branching fractions from Fourier transform spectra and from spectra recorded using a 3 m echelle spectrometer are combined with published radiative lifetimes from laser-induced fluorescence measurements to determine these transition probabilities. Generally good agreement is found in comparisons to the NIST Atomic Spectra Database. The new Ti I data are applied to re-determine the Ti abundance in the photospheres of the Sun and metal-poor star HD 84937 using many lines covering a range of wavelength and excitation potential to explore possible non-local thermal equilibrium effects. The variation of relative Ti/Fe abundance with metallicity in metal-poor stars observed in earlier studies is supported in this study.

Lawler, J. E.; Guzman, A.; Wood, M. P.; Sneden, C.; Cowan, J. J.

2013-04-01

43

Probability Boxes  

NSDL National Science Digital Library

In this cooperative learning activity students conduct an experiment in probability. For this lesson, students work in groups to pull items one at a time from mystery boxes, answering questions, and predicting outcomes for eight different boxes. Throughout this activity students learn to use the terms: possible, event, predict, probability, impossible, unlikely, equally likely, likely, certain, least likely, most likely, and as likely as. This lesson plan includes a data recording sheet and an assessment sheet in PDF format.

2011-01-01

44

Probability Distribution of Leadtime Demand.  

National Technical Information Service (NTIS)

This study examines 11 probability distributions to determine which distribution best describes demand during leadtime for 1H Congnizance Symbol (Cog) material. Proper selection of the distribution is criteria in the accurate calculation of reorder levels...

A. P. Urban J. A. Mellinger G. Evans

1984-01-01

45

Probability Tutorials  

NSDL National Science Digital Library

Created by Noel Vaillant, PhD from Imperial College, London, these 20 probability tutorials "are meant to be a complete online course on measure theory, lebesgue integration and probability." The exercises are designed to give students all the necessary tools to prove problems themselves. There are solutions for tutorials 1-6, and more are regularly added. Tutorial headings include Dynkin systems, Measurability, Lebesque integration, and Complex measures. Also, the page offers sections on definitions, theorems, history, and links. These self-contained tutorials may be difficult for those without a first degree in Math.

Vaillant, Noel.

46

Posterior sternoclavicular dislocations  

Microsoft Academic Search

The frequency of posterior sternoclavicular dislocations represents 0.019% of the shoulder injuries in the Centre of Traumatology\\u000a and Orthopedics of Dakar. The posterior form is 0.033% compared to the anterior form. The authors report the cases of posterior\\u000a sternoclavicular dislocations, occurred with seven men and one woman. Seven of these dislocations were located on the left\\u000a side, including one case

El Hadji Souleymane Camara; Ablaye Bousso; Mouhamed Tall; Mouhamed Habib Sy

2009-01-01

47

Prior Probabilities  

Microsoft Academic Search

In decision theory, mathematical analysis shows that once the sampling distribution, loss function, and sample are specified, the only remaining basis for a choice among different admissible decisions lies in the prior probabilities. Therefore, the logical foundations of decision theory cannot be put in fully satisfactory form until the old problem of arbitrariness (sometimes called \\

Edwin Jaynes

1968-01-01

48

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.

2008-12-30

49

Probably Graphing  

NSDL National Science Digital Library

Student will conduct a coin tossing experiment for 30 trials. Their results will be graphed, showing a line graph that progresses toward the theoretical probability. Students will observe that as the number of trials increases they begin to see a graphical representation of the Law of Large Numbers. Instructions, handouts, and a lesson extension are all included here.

Heitschmidt, Corey

2000-01-01

50

Confidence Probability versus Detection Probability  

SciTech Connect

In a discovery sampling activity the auditor seeks to vet an inventory by measuring (or inspecting) a random sample of items from the inventory. When the auditor finds every sample item in compliance, he must then make a confidence statement about the whole inventory. For example, the auditor might say: ''We believe that this inventory of 100 items contains no more than 5 defectives with 95% confidence.'' Note this is a retrospective statement in that it asserts something about the inventory after the sample was selected and measured. Contrast this to the prospective statement: ''We will detect the existence of more than 5 defective items in this inventory with 95% probability.'' The former uses confidence probability while the latter uses detection probability. For a given sample size, the two probabilities need not be equal, indeed they could differ significantly. Both these probabilities critically depend on the auditor's prior belief about the number of defectives in the inventory and how he defines non-compliance. In other words, the answer strongly depends on how the question is framed.

Axelrod, M

2005-08-18

51

Probability Resources  

NSDL National Science Digital Library

This collection from the MAA Mathematical Sciences Digital Library brings together probability resources from a wide range of sources. First-time visitors can look through topics such as basic probability, games of chance, various discrete and continuous distributions, and more. As they browse around, visitors will notice that each resource has a title, a format, a rating, and a link to more information. The formats are quite diverse, and include interactive graphics, instructional fact sheets, and so on. All told, there are several hundred resources here that could be used in high school and college mathematics classrooms. Perhaps the most interesting sections here are the Famous Problems, which include the celebrated Monty Hall problem and the "birds on a wire."

52

Probability Distributions  

NSDL National Science Digital Library

This page, created by Virginia Tech's Department of Statistics, provides users with a myriad of different applets presenting different probability distributions. Some of these include: binomial, Poisson, negative binomial, geometric, t, chi-squared, gamma, Weibull, log-normal, beta and f distributions. Each applet is presented with an explanation of its use and also an example. Featuring eleven different applets, this is a useful and plentiful resource.

Anderson-Cook, C.; Robinson, T.; Dorai-Raj, S.

2009-10-28

53

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.

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

2012-01-01

54

Markov chain Monte Carlo posterior sampling with the Hamiltonian method  

Microsoft Academic Search

A major advantage of Bayesian data analysis is that provides a characterization of the uncertainty in the model parameters estimated from a given set of measurements in the form of a posterior probability distribution. When the analysis involves a complicated physical phenomenon, the posterior may not be available in analytic form, but only calculable by means of a simulation code.

Kenneth M. Hanson; Kenneth M

2001-01-01

55

Accurate confidence intervals for binomial proportion and Poisson rate estimation.  

PubMed

Estimates of proportion and rate-based performance measures may involve discrete distributions, small sample sizes, and extreme outcomes. Common methods for uncertainty characterization have limited accuracy in these circumstances. Accurate confidence interval estimators for proportions, rates, and their differences are described and MATLAB programs are made available. The resulting confidence intervals are validated and compared to common methods. The programs search for confidence intervals using an integration of the Bayesian posterior with diffuse priors to measure the confidence level. The confidence interval estimators can find one or two-sided intervals. For two-sided intervals, either minimal-length, balanced-tail probabilities, or balanced-width can be selected. PMID:12878234

Ross, Timothy D

2003-11-01

56

Posterior bone block procedure for posterior shoulder instability  

Microsoft Academic Search

The posterior bone block procedure is an uncommon surgical procedure used in the treatment of posterior shoulder instability.\\u000a The purpose of this study is to report the results of the posterior bone block procedure in the treatment of posterior shoulder\\u000a instability. We retrospectively reviewed 21 shoulders that had undergone a posterior bone block procedure in the treatment\\u000a of recurrent posterior

Elvire Servien; Gilles Walch; Zenia E. Cortes; T. Bradley Edwards; Daniel P. O’Connor

2007-01-01

57

[Bilateral posterior scleritis].  

PubMed

Posterior scleritis is an inflammatory process of the posterior part of the sclera. Its prevalence is very low and its diagnosis can be complicated due to the absence of external ocular signs. It is more frequent in women. In young patients it does not usually have other associated pathologies, but in those over 55 years nearly one-third of the cases have a relation with some systemic disease, above all rheumatoid arthritis. The diagnosis of this pathology can require a multidisciplinary approach and the collaboration of ophthalmologists with neurologists, internists or rheumatologists. This article describes a case of idiopathic bilateral posterior scleritis. PMID:21904415

Zurutuza, A; Andonegui, J; Berástegui, L; Arruti, N

58

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

59

Posterior Cruciate Ligament Injuries  

MedlinePLUS

... into two pieces, and the knee joint is unstable. Posterior cruciate ligament tears tend to be partial ... cause a limp Difficulty walking The knee feels unstable, like it may "give out" Top of page ...

60

Posterior interosseous neuropathy: electrodiagnostic evaluation.  

PubMed

Electrodiagnostic studies are used to anatomically localize nerve injuries. These tests help differentiate between cervical radiculopathies, brachial plexopathies, and peripheral nerve injuries. They also help to identify or rule out other underlying neurological diseases and disorders. In this case report, a 22-year-old male swimmer presented with left finger extensor weakness following pull-up exercises. Left wrist extension remained intact. Electrodiagnostic testing revealed a severe but incomplete posterior interosseous neuropathy. Magnetic resonance imaging confirmed inflammation of the nerve in the forearm. Posterior interosseous neuropathy is an uncommon but well-studied condition. Typically, this condition presents with weakness in finger and thumb extension with preserved wrist extension as the extensor carpi radialis longus is innervated proximal to the site of nerve compression in most cases. It is important to understand the anatomic course and distribution of the radial nerve in order to make an accurate diagnosis. Once the anatomy is understood, electrodiagnostic testing may be used to identify the location of nerve injury and exclude other disorders. PMID:23874261

Bevelaqua, Anna-Christina; Hayter, Catherine L; Feinberg, Joseph H; Rodeo, Scott A

2012-01-24

61

Complications of posterior sagittal anorectoplasty.  

PubMed

From 1982 to 1985, 23 patients underwent posterior sagittal anorectoplasty procedures: 12 as primary treatment for congenital anorectal malformations, 9 for treatment of fecal incontinence following a prior pull-through procedure, and 2 for treatment of fecal incontinence following trauma. Six patients (26%) developed seven complications specifically related to the procedure. One patient with a cloacal anomaly had partial dehiscence of the sacroperineal incision following total reconstruction. This resulted in retraction of vaginal and anal openings, which, however, have remained separate and patent. Two patients developed temporary femoral nerve palsies, unilateral in one patient lasting one week, and bilateral in one patient lasting four months. Four patients developed leaks from the suture line of the tailored ectatic rectum, which was pulled through to the perineum. In one male patient, the suture line was placed anteriorly, resulting in a rectourethral fistula, which required a repeat posterior sagittal dissection. One male, who had a redo procedure, developed a posterior diverticulum comparable to a large anal crypt. This was repaired prior to closure of the colostomy. One seven-year-old girl developed multiple rectocutaneous fistulae, which closed with conservative management in five months. One male infant developed a single supralevator rectocutaneous fistula, which closed after rediversion of feces with a colostomy and has remained so after colostomy closure. The majority of the complications encountered were probably preventable if careful attention to certain details of technique had been observed: careful padding of the groin areas when patients are prone, especially in older patients.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3723300

Nakayama, D K; Templeton, J M; Ziegler, M M; O'Neill, J A; Walker, A B

1986-06-01

62

The tibialis posterior tendon  

PubMed Central

The tibialis posterior tendon is the largest and anteriormost tendon in the medial ankle. It produces plantar flexion and supination of the ankle and stabilizes the plantar vault. Sonographic assessment of this tendon is done with high-frequency, linear-array transducers; an optimal examination requires transverse retromalleolar, longitudinal retromalleolar, and distal longitudinal scans, as well as dynamic studies. Disorders of the posterior tibial tendon include chronic tendinopathy with progressive rupture, tenosynovitis, acute rupture, dislocation and instability, enthesopathies. The most common lesion is a progressive “chewing gum” lesion that develops in a setting of chronic tendinopathy; it is usually seen in overweight women over 50 years of age with valgus flat feet. Medial ankle pain must also be carefully investigated, and the presence of instability assessed with dynamic maneuvers (forced inversion, or dorsiflexion) of the foot. Sonography plays an important role in the investigation of disorders involving the posterior tibial tendon.

Lhoste-Trouilloud, A.

2012-01-01

63

Syphilitic posterior placoid chorioretinitis.  

PubMed

We present a case of syphilitic posterior placoid chorioretinitis, an uncommon but distinct ocular manifestation of syphilis. Because of the ocular findings, a lumbar puncture was performed to evaluate for neurosyphilis, which was positive. The ocular symptoms resolved with intravenous penicillin. PMID:24113406

Gorovoy, Ian R; Desai, Shilpa

2013-11-01

64

Posterior Cruciate Ligament Recession  

Microsoft Academic Search

Summary: Three cases of posterior cruciate ligament (PCL) laxity without posterolateral rotatory instability had magnetic resonance imaging scans that documented the structural continuity of the PCL. Tibial PCL recession was effective in eliminating symptomatic laxity in 1 case and lacked efficacy in the other 2 cases.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 15, No 6 (July), 1999: pp

Eugene E. Berg

1999-01-01

65

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.

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

2012-01-01

66

Posterior shape models.  

PubMed

We present a method to compute the conditional distribution of a statistical shape model given partial data. The result is a "posterior shape model", which is again a statistical shape model of the same form as the original model. This allows its direct use in the variety of algorithms that include prior knowledge about the variability of a class of shapes with a statistical shape model. Posterior shape models then provide a statistically sound yet easy method to integrate partial data into these algorithms. Usually, shape models represent a complete organ, for instance in our experiments the femur bone, modeled by a multivariate normal distribution. But because in many application certain parts of the shape are known a priori, it is of great interest to model the posterior distribution of the whole shape given the known parts. These could be isolated landmark points or larger portions of the shape, like the healthy part of a pathological or damaged organ. However, because for most shape models the dimensionality of the data is much higher than the number of examples, the normal distribution is singular, and the conditional distribution not readily available. In this paper, we present two main contributions: First, we show how the posterior model can be efficiently computed as a statistical shape model in standard form and used in any shape model algorithm. We complement this paper with a freely available implementation of our algorithms. Second, we show that most common approaches put forth in the literature to overcome this are equivalent to probabilistic principal component analysis (PPCA), and Gaussian Process regression. To illustrate the use of posterior shape models, we apply them on two problems from medical image analysis: model-based image segmentation incorporating prior knowledge from landmarks, and the prediction of anatomically correct knee shapes for trochlear dysplasia patients, which constitutes a novel medical application. Our experiments confirm that the use of conditional shape models for image segmentation improves the overall segmentation accuracy and robustness. PMID:23837968

Albrecht, Thomas; Lüthi, Marcel; Gerig, Thomas; Vetter, Thomas

2013-06-15

67

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…

Kern, John C.

2006-01-01

68

Posterior relaxing retinotomy.  

PubMed

Three patients with retinal detachments complicated by proliferative vitreoretinopathy underwent posteriorly located relaxing retinotomy to facilitate retinal reattachment. Six months postoperatively the retina remained attached in all cases, with an improvement in visual acuity in two cases (light perception to hand motion and 20/200 to 20/60) and a drop of one line in visual acuity in the third (20/20 to 20/25). PMID:2812694

Gremillion, C M; Peyman, G A

1989-09-01

69

Random Search for a Probable Object.  

National Technical Information Service (NTIS)

A search is undertaken for an object thought to be present with an unknown probability, using a detection scheme whose efficiency is also uncertain. After a certain interval, the search is called off, with the object unfound; what are the posterior-to-exp...

W. S. Jewell

1985-01-01

70

Facial Shape Localization Using Probability Gradient Hints  

Microsoft Academic Search

This letter proposes a novel method to localize facial shape represented by a series of facial landmarks. In our method, the problem of facial shape localization is formulated with a Bayesian inference. Specifically, given a face image, the posterior probability of the facial shape is naturally decomposed into two parts: the likelihood function of local textures and the prior constraints

Zhiheng Niu; Shiguang Shan; Xilin Chen

2009-01-01

71

[Posttraumatic posterior knee instability].  

PubMed

At the department of the sport and ballet trauma new methods of arthroscopic management of posterior posttraumatic knee instability (posterior static stabilization of knee joint with using of single-banded and double-banded transplants) in dependence on the kind, degree and form of instability, were worked out and implemented into clinical practice. Such methods permit to attain a compensated or subcompensated form of knee joint stability. Ad hoc methods of management were used in 23 patients (20 males and 3 females). A total of 62 patients (51 males and 11 females) got operative treatment at the department, that permitted us to estimate fairly different methods of operative treatment of posttraumatic posterior knee joint instability. An operational intervention was performed in average 6 month after trauma. We received data in patients which had been treated with use of new methods of operative treatment as follows: good results were drawn in 93.3% (22 patients), satisfactory results--in 6.7% of cases (1 patient). PMID:18819354

Mironov, S P; Orletski?, A K; Butkova, L L

2008-01-01

72

Human posterior subcapsular cataracts.  

PubMed

Clinically and pathologically there are two kinds of posterior subcapsular cataracts: vacuolar-lacy and solid plaque. Vacuolar opacities occur in senile, diabetic, retinitis pigmentosa, steroid, and secondary cataracts (Elschnig pearls). Plaque opacities occur in congenital polar, myotonic dystrophy, and Turner syndrome (chromosome XO) cataracts. The vacuolar opacities tend to be more superficial (closer to the posterior capsule), whereas the plaque opacities are generally slightly deeper (more cortical). The vacuolar opacities show cellular proliferation of aberrantly migrated lens epithelial cells in the posterior pole which have added damage to the cataract by secretion of basement membrane, intra- and extra-cellular filaments, and release of cytolytic lysozymes causing liquefaction and necrosis. The plaque opacities are acellular. Both types of cataracts show breakdown of lens fibres into rounded up disorganized globules and some membranous whorls. The liquefied vacuolar opacity is more readily removed by extracapsular cataract extraction, but the retention of nucleated lens epithelial cells in the vacuolar type of opacity is the source of a secondary cataract or Hirchberg-Elschnig pearls which require a discussion or membranectomy to clear the visual axis. This article will review the salient features in the histopathology (light and electron microscopy) and morphology of PSC and amalgamate the findings reported by several investigators (Eshagian and Streeten, 1975; Eshagian, March, Goossens, and Rafferty, 1978, 1978; Eshagian, Rafferty, and Goossens, 1980, 1981; Eshagian, Rafferty, Goossens, and March, 1979; 1980; Streeten and Eshagian, 1978). PMID:6964282

Eshagian, J

1982-01-01

73

Sixteen months' experience with 140 posterior chamber intraocular lens implants.  

PubMed Central

Three main designs of posterior chamber lenses in 140 cases have been reviewed. The visual results are satisfactory; patient satisfaction is good; and postoperative complications are limited to anterior dislocation of the feet of the lens and the necessity to wash out cortical remnants from behind the prosthesis in a small percentage of cases. The posterior chamber prosthesis is free from some of the complications of other intraocular lenses and probably provides the most 'normal' looking eye of any pseudophakoi. Images

Pearce, J. L.

1977-01-01

74

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

75

Does probability weighting matter in probability elicitation?  

Microsoft Academic Search

One of the most widely used methods for probability encoding in decision analysis uses binary comparisons (choices) between two lotteries: one that depends on the values of the random variable of interest and another that is contingent on an external reference chance device (typically a probability wheel). This note investigates the degree to which differences in probability weighting functions between

David Budescu; Ali Abbas; Lijuan Wu

2011-01-01

76

Posterior cortical atrophy.  

PubMed

Posterior cortical atrophy (PCA) is a neurodegenerative syndrome that is characterised by progressive decline in visuospatial, visuoperceptual, literacy, and praxic skills. The progressive neurodegeneration affecting parietal, occipital, and occipitotemporal cortices that underlies PCA is attributable to Alzheimer's disease in most patients. However, alternative underlying causes, including dementia with Lewy bodies, corticobasal degeneration, and prion disease, have also been identified, and not all patients with PCA have atrophy on clinical imaging. This heterogeneity has led to inconsistencies in diagnosis and terminology and difficulties in comparing studies from different centres, and has restricted the generalisability of findings from clinical trials and investigations of factors that drive phenotypic variability. Important challenges remain, including the identification of factors associated not only with the selective vulnerability of posterior cortical regions but also with the young age of onset of PCA. Greater awareness of the syndrome and agreement over the correspondence between syndrome-level and disease-level classifications are needed to improve diagnostic accuracy, clinical management, and the design of research studies. PMID:22265212

Crutch, Sebastian J; Lehmann, Manja; Schott, Jonathan M; Rabinovici, Gil D; Rossor, Martin N; Fox, Nick C

2012-02-01

77

Ordering genes: controlling the decision-error probabilities.  

PubMed Central

Determination of the relative gene order on chromosomes is of critical importance in the construction of human gene maps. In this paper we develop a sequential algorithm for gene ordering. We start by comparing three sequential procedures to order three genes on the basis of Bayesian posterior probabilities, maximum-likelihood ratio, and minimal recombinant class. In the second part of the paper we extend sequential procedure based on the posterior probabilities to the general case of g genes. We present a theorem that states that the predicted average probability of committing a decision error, associated with a Bayesian sequential procedure that accepts the hypothesis of a gene-order configuration with posterior probability equal to or greater than pi *, is smaller than 1 - pi *. This theorem holds irrespective of the number of genes, the genetic model, and the source of genetic information. The theorem is an extension of a classical result of Wald, concerning the sum of the actual and the nominal error probabilities in the sequential probability ratio test of two hypotheses. A stepwise strategy for ordering a large number of genes, with control over the decision-error probabilities, is discussed. An asymptotic approximation is provided, which facilitates the calculations with existing computer software for gene mapping, of the posterior probabilities of an order and the error probabilities. We illustrate with some simulations that the stepwise ordering is an efficient procedure.

Rogatko, A; Zacks, S

1993-01-01

78

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.

Pearce, Jeanine; Streck, Tracey

2009-01-01

79

[Posterior reversible encephalopathy syndrome].  

PubMed

INTRODUCTION: Reversible Posterior Leukoencephalopathy Syndrome was introduced into clinical practice in 1996 in order to describe unique syndrome, clinically expressed during hypertensive and uremic encephalopathy, eclampsia and during immunosuppressive therapy [1]. First clinical investigations showed that leucoencephalopathy is major characteristic of the syndrome, but further investigations showed no significant destruction in white cerebral tissue [2, 3, 4]. In majority of cases changes are localise in posterior irrigation area of the brain and in the most severe cases anterior region is also involved. Taking into consideration all above mentioned facts, the suggested term was Posterior Reversible Encephalopathy Syndrome (PRES) for the syndrome clinically expressed by neurological manifestations derived from cortical and subcortical changes localised in posterior regions of cerebral hemispheres, cerebral trunk and cerebellum [5]. CASE REPORT: Patient, aged 53 years, was re-hospitalized in Cardiovascular Institute "Dediwe" two months after successful aorto-coronary bypass performed in June 2001 due to the chest bone infection. During the treatment of the infection (according to the antibiogram) in September 2001, patient in evening hours developed headache and blurred vision. The recorded blood pressure was 210/120 mmHg so antihypertensive treatment was applied (Nifedipin and Furosemid). After this therapy there was no improvement and intensive headache with fatigue and loss of vision developed. Neurological examination revealed cortical blindness and left hemiparesis. Manitol (20%, 60 ccm every 3 hours) and i.v. Nytroglicerin (high blood pressure). Brain CT revealed oedema of parieto-occipital regions of both hemispheres, more emphasized on the right. (Figure 1a, b, c). There was no sign of focal ischemia even in deeper sections (Figure 1d, e, f). Following three days enormous high blood pressure values were registered. On the fourth day the significant clinical improvement occurred with lowering of blood pressure, better mental state and better vision. There was no sign of left hemiparesis on the 7th day. On the 9th day there were no symptoms or sign of disease. Control brain CT (15th day) was normal. ETHIOPATHOGENESIS: Most common causes of PRES are hypertensive encephalopathy [6-8], pre-eclampsia/eclampsia [9-12] cyclosporin A administration [13-22] and uremic encephalopathy [23]. There are several theories about the mechanism for PRES in hypertensive encephalopathy (reversible vasospasm and hyperperfusion) and administration of cyclosporin A (neurotoxic effect). CLINICAL PICTURE: Most common symptoms are headache, nausea, vomiting, confusion, behavioural changes, changes of conciousness (from somnolencia to stupor), vision disturbances (blurred vision, haemianopsia, cortical blindness) and epileptic manifestations (mostly focal attacks with secondary generalisation). Mental functions are characterised with decreased activity and reactivity, confusion, loss of concentration and mild type of amnesia. Lethargy is often initial sign, sometimes accompanied with phases of agitation. Stupor and coma rarely occurred. DIAGNOSIS: In patients with hypertensive encephalopathy and eclampsia high blod pressure is registered. Neurological examination revealed vision changes and damages of mental function as well as increased reflex activity. Today, brain MRI and CT are considered the most important diagnostic method for the diagnosis and follow-up of patients with PRES [6]. Brain MRI better detects smaller focal parenhim abnormalities than brain CT. The most often neuroradiological finding is relatively symmetrical oedema of white cerebral tissue in parieto-occipital regions of both cerebral hemispheres. Gray cerebral tissue is sometimes involved, usually in mild form of disease. Diagnosis of this "cortical" form of PRES is possible by MR FLAIR (Fluid-Attenuated Inversion Recovery) technique [5]. TREATMENT: Therapeutic strategy depends on the cause of PRES and clinical picture. Most important are blood pres

Petrovi?, Branko; Kosti?, Vladimir; Sterni?, Nadezda; Kolar, Jovo; Tasi?, Nebojsa

80

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

81

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

82

Posterior plagiocephaly: proactive conservative management  

Microsoft Academic Search

SUMMARY.The pathology, diagnosis and management of posterior plagiocephaly remains highly controversial. While the rationale for surgical management of true lambdoid synostosis is undisputed, opinions vary greatly on how to manage severe, unresolving, non-synostotic cases. We reviewed 39 cases of posterior plagiocephaly, 37 of which were treated conservatively. Of these, 34 patients had a significant improvement over the following year with

E. S. O’Broin; D. Allcutt; M. J. Earley

1999-01-01

83

Unilateral upper cervical posterior spinal artery syndrome following sneezing  

Microsoft Academic Search

A 35 year old man experienced severe transitory neck pain following a violent sneeze. This was followed by neurological symptoms and signs indicating a left sided upper cervical cord lesion. MRI showed an infarct at this site in the territory of the left posterior spinal artery. This discrete infarct was probably due to partial left vertebral artery dissection secondary to

N J Gutowski; R P Murphy; D J Beale

1992-01-01

84

Segmentation of MR Image Based on Maximum A Posterior.  

National Technical Information Service (NTIS)

Brain MR image segmentation takes an important role in research and clinical application. Statistical method is effective in the segmentation, which is usually based on maximum a posterior (MAP). The key of MAP method is to estimate a prior probability of...

F. Liu S. Gao X. Gao

2001-01-01

85

Simultaneous Tracking and Verification via Sequential Posterior Estimation  

Microsoft Academic Search

An approach to simultaneous tracking and verification in video data is presented. The approach is based on posterior estimation using sequential Monte Carlo methods. Visual tracking, which is in essence a temporal correspondence problem, is solved through probability density propagation, with the density being defined over a proper state space characterizing the object configuration. Verification is realized through hypothesis testing

Baoxin Li; Rama Chellappa

2000-01-01

86

Gossypiboma mimicking posterior urethral stricture  

PubMed Central

INTRODUCTION Foreign bodies in the urogenital tract are not uncommon. Hairpins, glass rods, umbilical tapes, ball point pen are described in lower urogenital tract. Retained gauze piece (gossypiboma) in posterior urethra may cause diagnostic dilemma. Symptoms and investigations may mimic stricture of posterior urethra. PRESENTATION OF CASE Two cases of retained gauze pieces in the urethra are described here. The micturating cystourethrogram was suggestive of posterior urethral stricture. DISCUSSION Two cases described here had retained gauze piece as a cause of filling defect and abnormal appearance in the micturating cystourethrogram. Gossypiboma may be a possibility where posterior urethral stricture are seen after previous surgery in paediatric age group. CONCLUSION In the setting of previous urogenital surgery gossypiboma should be kept in the differential diagnosis where posterior urethral stricture are seen in the paediatric age group.

Kumar, Bindey; Kumar, Prem; Sinha, Sanjay Kumar; Sinha, Neelam; Hasan, Zaheer; Thakur, Vinit Kumar; Anand, Utpal; Priyadarshi, Rajiv Nayan; Mandal, Manish

2013-01-01

87

Terrorism and Probability Neglect  

Microsoft Academic Search

When strong emotions are involved, people tend to focus on the badness of the outcome, rather than on the probability that the outcome will occur. The resulting “probability neglect” helps to explain excessive reactions to low-probability risks of catastrophe. Terrorists show a working knowledge of probability neglect, producing public fear that might greatly exceed the discounted harm. As a result

Cass R. Sunstein; Karl N. Llewellyn

2003-01-01

88

Estimating extreme flood probabilities  

Microsoft Academic Search

Estimates of the exceedance probabilities of extreme floods are needed for the assessment of flood hazard at Department of Energy facilities. A new approach using a joint probability distribution of extreme rainfalls and antecedent soil moisture conditions, along with a rainfall runoff model, provides estimates of probabilities for floods approaching the probable maximum flood. This approach is illustrated for a

T. A. Fontaine; K. W. Potter; C. A. Rodgers

1994-01-01

89

Grading More Accurately  

ERIC Educational Resources Information Center

|Grades matter. College grading systems, however, are often ad hoc and prone to mistakes. This essay focuses on one factor that contributes to high-quality grading systems: grading accuracy (or "efficiency"). I proceed in several steps. First, I discuss the elements of "efficient" (i.e., accurate) grading. Next, I present analytical results…

Rom, Mark Carl

2011-01-01

90

Positive, accurate animal identification  

Microsoft Academic Search

Positive, accurate identification of animals and their products would be very helpful in livestock commerce, prevention of theft and fraud and in tracing animals and products to origin. Food safety, animal health, and prevention of epidemics, would be enhanced by combining identification with location. Identification may be by electronic chips, iris or retinal scans, antibody or DNA analysis. A cross

Philip Dziuk

2003-01-01

91

Keratoglobus and posterior subcapsular cataract  

Microsoft Academic Search

We report sporadic, bilateral keratoglobus associated with posterior subcapsular cataract in a 43-year-old man. Slitlamp biomicroscopy showed symmetric arcus senilis-like deposits, a polygonal appearance resembling crocodile shagreen, an unusual endothelial appearance, and posterior subcapsular cataract. Orbscan® II pachymetry maps (Bausch & Lomb) demonstrated bilateral diffuse corneal thinning (359.53 ?m ± 21.15 [SD] in the right eye and 379.61 ± 11.49

Judy Y. F Ku; Christina N Grupcheva; Michael J Fisk; Franzco; Charles N. J McGhee

2004-01-01

92

Evolution and Probability.  

ERIC Educational Resources Information Center

|Some of the most impressive-sounding criticisms of the conventional theory of biological evolution involve probability. Presents a few examples of how probability should and should not be used in discussing evolution. (ASK)|

Bailey, David H.

2000-01-01

93

Assessment of Subjective Probability.  

National Technical Information Service (NTIS)

The assessment of subjective probability is of great interest in risk analysis. Some aids for assessing subjective probability are surveyed. The connection with statistical inference and recent papers on statistical foundations are discussed. (Author)

R. E. Barlow

1981-01-01

94

Probability on a Budget.  

ERIC Educational Resources Information Center

|Describes how to use common dice numbered 1-6 for simple mathematical situations including probability. Presents a lesson using regular dice and specially marked dice to explore some of the concepts of probability. (KHR)|

Ewbank, William A.; Ginther, John L.

2002-01-01

95

Probability Gate Statistics.  

National Technical Information Service (NTIS)

A probability gate presents a fixed but controllable transmission probability p to pulses arriving at its input. This report describes some statistical properties of the transformation imposed by a gate on the input distribution of interpulse intervals. T...

J. N. Cronholm

1970-01-01

96

What Is Probability?  

Microsoft Academic Search

Probabilities may be subjective or objective; we are concerned with both\\u000akinds of probability, and the relationship between them. The fundamental theory\\u000aof objective probability is quantum mechanics: it is argued that neither Bohr's\\u000aCopenhagen interpretation, nor the pilot-wave theory, nor stochastic\\u000astate-reduction theories, give a satisfactory answer to the question of what\\u000aobjective probabilities are in quantum mechanics, or

Simon Saunders

1969-01-01

97

Intuitionistic Fuzzy Probability  

Microsoft Academic Search

\\u000a Fuzzy Probabilities are an extension of the concept of probabilities with application in several practical problems. The former\\u000a are probabilities represented through fuzzy numbers, to indicate the uncertainty in the value assigned to a probability. Moreover,\\u000a Krassimir Atanassov in 1983 added an extra degree of uncertainty to classic fuzzy sets for modeling the hesitation and uncertainty\\u000a about the degree of

Claudilene Gomes da Costa; Benjamín C. Bedregal; Adrião Duarte Dória Neto

2010-01-01

98

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

99

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.

Taboga, Marco

2010-08-23

100

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

101

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 ...

Taylor, Ms.

2009-05-03

102

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

103

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

104

Representativeness and conjoint probability.  

PubMed

People commonly violate a basic rule of probability, judging a conjunction of events to be more probable than at least 1 of its component events. Many manifestations of this conjunction fallacy have been ascribed to people's reliance on the representativeness heuristic for judging probability. Some conjunction fallacies, however, have been ascribed to the incorrect rules people use to combine probabilities. In 2 experiments, representativeness was pitted against probability combination to determine the contributions of each to the fallacy. Even for exemplar representativeness problems, the fallacy stemmed primarily from the application of incorrect combination rules. Representativeness seemed to be involved only insofar as it influenced the probabilities of a conjunction's component events. Implications of these findings are discussed for the representativeness account of judgmental errors and the relation between similarity and probability. PMID:1920061

Gavanski, I; Roskos-Ewoldsen, D R

1991-08-01

105

In All Probability, Probability is not All  

ERIC Educational Resources Information Center

|The national lottery is often portrayed as a game of pure chance with no room for strategy. This misperception seems to stem from the application of probability instead of expectancy considerations, and can be utilized to introduce the statistical concept of expectation.|

Helman, Danny

2004-01-01

106

Escape and transmission probabilities in cylindrical geometry  

SciTech Connect

An improved technique for the generation of escape and transmission probabilities in cylindrical geometry was applied to the existing resonance cross section processing code ROLAIDS. The algorithm of Hwang and Toppel, (ANL-FRA-TM-118) (with modifications) was employed. The probabilities generated were found to be as accurate as those given by the method previously applied in ROLAIDS, while requiring much less computer core storage and CPU time. (RWR)

Bjerke, M.A.

1980-01-01

107

Naive probability: a mental model theory of extensional reasoning.  

PubMed

This article outlines a theory of naive probability. According to the theory, individuals who are unfamiliar with the probability calculus can infer the probabilities of events in an extensional way: They construct mental models of what is true in the various possibilities. Each model represents an equiprobable alternative unless individuals have beliefs to the contrary, in which case some models will have higher probabilities than others. The probability of an event depends on the proportion of models in which it occurs. The theory predicts several phenomena of reasoning about absolute probabilities, including typical biases. It correctly predicts certain cognitive illusions in inferences about relative probabilities. It accommodates reasoning based on numerical premises, and it explains how naive reasoners can infer posterior probabilities without relying on Bayes's theorem. Finally, it dispels some common misconceptions of probabilistic reasoning. PMID:10197363

Johnson-Laird, P N; Legrenzi, P; Girotto, V; Legrenzi, M S; Caverni, J P

1999-01-01

108

Explaining Glaciers, Accurately  

NSDL National Science Digital Library

What happens when a geology graduate student and two fourth-grade teachers collaborate on lessons for the classroom? They discover interesting and practical ways to explore geology and other scientific concepts, that's what! Here they share the glacial erosion lessons that grew out of the geologist's frustration at finding glacial erosion labs erroneously showing glaciers eroding by pushing rocks. Their goal was to find a way to show and explain glacial erosion more accurately and in a way that elementary age students could understand.

Tate, Mari; Faw, Mary; Scott, Nancy

2009-04-01

109

Neural Network Classifiers Estimate Bayesian a posteriori Probabilities  

Microsoft Academic Search

Many neural network classifiers provide outputs which estimate Bayesian a posteriori probabilities. When the estimation is accurate, network outputs can be treated as probabilities and sum to one. Simple proofs show that Bayesian probabilities are estimated when desired network outputs are 1 of M (one output unity, all others zero) and a squared-error or cross-entropy cost function is used. Results

Michael D. Richard; Richard P. Lippmann

1991-01-01

110

Reasoning defeasibly about probabilities  

Microsoft Academic Search

In concrete applications of probability, statistical investigation gives us knowledge of some probabilities, but we generally\\u000a want to know many others that are not directly revealed by our data. For instance, we may know prob(P\\/Q) (the probability of P given Q) and prob(P\\/R), but what we really want is prob(P\\/Q&R), and we may not have the data required to assess

John L. Pollock

2011-01-01

111

Regional flood probabilities  

Microsoft Academic Search

The T-year annual maximum flood at a site is defined to be that streamflow, that has probability 1\\/T of being exceeded in any given year, and for a group of sites the corresponding regional flood probability (RFP) is the probability that at least one site will experience a T-year flood in any given year. The RFP depends on the number

Brent M. Troutman; Michael R. Karlinger

2003-01-01

112

Backward Probability Template  

NSDL National Science Digital Library

Given the population incidence of a certain disease, and the conditional probabilities of positive and negative test results, what are the probabilities for a particular test result of a true positive, true negative, false positive, and false negative? Adaptable to other kinds of conditional situations. Although this page is adaptable to a variety of backward probability situations, its exemplary case is the one in which one is seeking to make sense of the result of a medical test.

Lowry, Richard

2009-10-06

113

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).

2010-12-27

114

Genetics and Probability  

NSDL National Science Digital Library

This is a lab for middle school or high school students exploring how probability applies to genetics. Students collect data using beads and a coin as examples of alleles. The analysis questions walk students through the steps of expressing probabilities as a fraction or as a decimal. The students are also asked to draw a Punnett square which relates probability to offspring of a particular cross.

Dr. Jennifer J Taylor (Washington University)

2009-03-30

115

Posterior polar cataract: A review  

PubMed Central

Posterior polar cataract is a rare form of congenital cataract. It is usually inherited as an autosomal dominant disease, yet it can be sporadic. Five genes have been attributed to the formation of this disease. It is highly associated with complications during surgery, such as posterior capsule rupture and nucleus drop. The reason for this high complication rate is the strong adherence of the opacity to the weak posterior capsule. Different surgical strategies were described for the handling of this challenging entity, most of which emphasized the need for gentle maneuvering in dealing with these cases. It has a unique clinical appearance that should not be missed in order to anticipate, avoid, and minimize the impact of the complications associated with it.

Kalantan, Hatem

2011-01-01

116

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

2009-08-06

117

Probability (Program Description)  

NSF Publications Database

... Program supports research on the theory and applications of probability. Subfields include discrete ... systems, stochastic differential and partial differential equations, and Markov processes. Research ...

118

Arbitrarily accurate narrowband composite pulse sequences  

SciTech Connect

Narrowband composite pulse sequences containing an arbitrary number N of identical pulses are presented. The composite phases are given by a very simple analytic formula and the transition probability is merely sin{sup 2N}(A/2), where A is the pulse area. These narrowband sequences can be made accurate to any order with respect to variations in A for sufficiently many constituent pulses, i.e., excitation can be suppressed below any desired value for any pulse area but {pi}.

Vitanov, Nikolay V. [Department of Physics, Sofia University, 5 James Bourchier Boulevard, BG-1164 Sofia (Bulgaria)

2011-12-15

119

Accurate measurement of time  

NASA Astrophysics Data System (ADS)

The paper discusses current methods for accurate measurements of time by conventional atomic clocks, with particular attention given to the principles of operation of atomic-beam frequency standards, atomic hydrogen masers, and atomic fountain and to the potential use of strings of trapped mercury ions as a time device more stable than conventional atomic clocks. The areas of application of the ultraprecise and ultrastable time-measuring devices that tax the capacity of modern atomic clocks include radio astronomy and tests of relativity. The paper also discusses practical applications of ultraprecise clocks, such as navigation of space vehicles and pinpointing the exact position of ships and other objects on earth using the GPS.

Itano, Wayne M.; Ramsey, Norman F.

1993-07-01

120

Probability and Criminalistics  

Microsoft Academic Search

Probabilistic methods in the evaluation of legal evidence have not yet been employed to any large degree and there is a dearth of potentially useful probabilities that might be estimated from empirical data. The role which mathematical probability can and does play in the court room is illustrated with cases involving combinations of circumstances, forgery, criminal identification, establishment of nonpaternity,

Elmer B. Mode

1963-01-01

121

Teachers' Understandings of Probability  

ERIC Educational Resources Information Center

Probability is an important idea with a remarkably wide range of applications. However, psychological and instructional studies conducted in the last two decades have consistently documented poor understanding of probability among different populations across different settings. The purpose of this study is to develop a theoretical framework for…

Liu, Yan; Thompson, Patrick

2007-01-01

122

Probability: Playing with Fire  

NSDL National Science Digital Library

This lesson is designed to develop studentsâ 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.

2010-01-01

123

Teachers' Understandings of Probability  

ERIC Educational Resources Information Center

|Probability is an important idea with a remarkably wide range of applications. However, psychological and instructional studies conducted in the last two decades have consistently documented poor understanding of probability among different populations across different settings. The purpose of this study is to develop a theoretical framework for…

Liu, Yan; Thompson, Patrick

2007-01-01

124

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

125

Probability and Statistics  

Microsoft Academic Search

As an introductory definition, we consider probability to be a collection of con- cepts, methods, and interpretations that facilitate the investigation of nondeter- ministic phenomena. While more mathematically precise definitions will appear in due course, this broadly inclusive description certainly captures the nonspe- cialist's meaning of probability, and it also aligns rather closely with the in- tuitive appreciation shared by

James Johnson

2008-01-01

126

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; Daniels, John E.; Mckean, Joe W.; Kapenga, J. A.

2008-12-19

127

Estimating the Probability of Negative Events  

ERIC Educational Resources Information Center

How well we are attuned to the statistics of our environment is a fundamental question in understanding human behaviour. It seems particularly important to be able to provide accurate assessments of the probability with which negative events occur so as to guide rational choice of preventative actions. One question that arises here is whether or…

Harris, Adam J. L.; Corner, Adam; Hahn, Ulrike

2009-01-01

128

Changes of Probability Associated with El Niño  

Microsoft Academic Search

Away from the tropical Pacific Ocean, an ENSO event is associated with relatively minor changes of the probability distributions of atmospheric variables. It is nonetheless important to estimate the changes accurately for each ENSO event, because even small changes of means and variances can imply large changes of the likelihood of extreme values. The mean signals are not strictly symmetric

Prashant D. Sardeshmukh; Gilbert P. Compo; Cécile Penland

2000-01-01

129

Stereolithography for Posterior Fossa Cranioplasty  

PubMed Central

Posterior fossa cranioplasty has been suggested for improvement of neurological symptoms following craniectomy. However, there is no particular recommendation in the literature about techniques for prosthesis manufacture and implantation. We report our experience using rapid prototyping technology and stereolithography for pre-surgical implant design and production of cranioplasties. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5

Agner, Celso; Dujovny, Manuel; Evenhouse, Raymond; Charbel, Fady T.; Sadler, Lewis

1998-01-01

130

Posterior Distributions on Normalizing Constants  

Microsoft Academic Search

This article describes a procedure for defining a posterior distributionon the value of a normalizing constant or ratio of normalizing constantsusing output from Monte Carlo simulation experiments. The resultingposterior distribution provides a simple diagnostic for assessing the adequacyof a simulation experiment for estimating these quantities, and isparticularly useful in cases for which standard estimators perform poorly,since in such situations asymptotic

Valen E. Johnson

1999-01-01

131

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

132

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.

Forum, The M.

1998-01-01

133

Accurate Optical Reference Catalogs  

NASA Astrophysics Data System (ADS)

Current and near future all-sky astrometric catalogs on the ICRF are reviewed with the emphasis on reference star data at optical wavelengths for user applications. The standard error of a Hipparcos Catalogue star position is now about 15 mas per coordinate. For the Tycho-2 data it is typically 20 to 100 mas, depending on magnitude. The USNO CCD Astrograph Catalog (UCAC) observing program was completed in 2004 and reductions toward the final UCAC3 release are in progress. This all-sky reference catalogue will have positional errors of 15 to 70 mas for stars in the 10 to 16 mag range, with a high degree of completeness. Proper motions for the about 60 million UCAC stars will be derived by combining UCAC astrometry with available early epoch data, including yet unpublished scans of the complete set of AGK2, Hamburg Zone astrograph and USNO Black Birch programs. Accurate positional and proper motion data are combined in the Naval Observatory Merged Astrometric Dataset (NOMAD) which includes Hipparcos, Tycho-2, UCAC2, USNO-B1, NPM+SPM plate scan data for astrometry, and is supplemented by multi-band optical photometry as well as 2MASS near infrared photometry. The Milli-Arcsecond Pathfinder Survey (MAPS) mission is currently being planned at USNO. This is a micro-satellite to obtain 1 mas positions, parallaxes, and 1 mas/yr proper motions for all bright stars down to about 15th magnitude. This program will be supplemented by a ground-based program to reach 18th magnitude on the 5 mas level.

Zacharias, N.

2006-08-01

134

Probability and the East.  

National Technical Information Service (NTIS)

Following discourses on the nature of probability, from aspects of mathematics, economics, and human behavior, and of the Orient, the belief is propounded that the next big step in the progress of fundamental scientific theory will be distinctly oriental ...

E. W. Barankin

1964-01-01

135

Understanding Experimental Probability  

NSDL National Science Digital Library

Experiment with experimental probability using a fixed size section spinner, a variable section spinner, 2 regular 6-sided number cubes or design your own number cubes. Appropriate for elementary grades.

The Shodor Education Foundation, Inc.

2007-12-12

136

Probability and Statistical Inference  

Microsoft Academic Search

These lectures introduce key concepts in probability and statistical inference at a level suitable for graduate students in particle physics. Our goal is to paint as vivid a picture as possible of the concepts covered.

Harrison B. Prosper

2006-01-01

137

Collection of Probability Distributions.  

National Technical Information Service (NTIS)

A large number of probability distributions, with at least the first four moments known and methods of obtaining cumulative distribution functions or percentage points available, is presented. They do not include the common statistical distributions, such...

C. S. Davis M. A. Stephens

1985-01-01

138

Introduction to Probability  

NSDL National Science Digital Library

This website, created by J. Laurie Snell and Charles M. Grinstead of Dartmouth University, provides an online text version of Grinstead & Snell's "Introduction to Probability" as well as supplemental reference information. The book is made available in PDF format through an arrangement called the Free Document License (FDL), as published by the Free Software Foundation. The book "emphasizes the use of computing to simulate experiments and make computations." Additionally, there are links to experimental Java applets based around probability.

Grinstead, Charles M.; Snell, J. L.

2009-07-10

139

Classical probability waves  

Microsoft Academic Search

Probability waves in the configuration space are associated with coherent solutions of the classical Liouville or Fokker–Planck equations. Distributions localized in the momentum space provide action waves, described by the probability density and the generating function of the Hamilton–Jacobi theory. It is shown that by introducing a minimum distance in the coordinate space, the action distributions aquire the phase–space dispersion

Marius Grigorescu

2008-01-01

140

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

141

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

142

Analytical comparison between position specific posterior lattices and confusion networks based on words and subword units for spoken document indexing  

Microsoft Academic Search

In this paper we analytically compare the two widely accepted approaches of spoken document indexing, position specific posterior lattices (PSPL) and confusion network (CN), in terms of retrieval accuracy and index size. The fundamental distinctions between these two approaches in terms of construction units, posterior probabilities, number of clusters, indexing coverage and space requirements are discussed in detail. A new

Yi-cheng Pan; Hung-lin Chang; Lin-shan Lee

2007-01-01

143

Posterior fusion for Scheuermann's kyphosis.  

PubMed

Ten patients with Scheuermann's kyphosis were surgically treated with posterior spine fusion and Harrington heavy compression-rod instrumentation. This procedure relieved pain and deformity in all ten patients. The average follow-up period was 26.6 months. The average curve before surgery was 71.4 degrees and at follow-up examination was 39.3 degrees. The postoperative correction of kyphosis averaged 32 degrees (45%), with an average loss of correction of 7.8 degrees. Posterior fusion with Harrington heavy compression-rod instrumentation may prove to be the procedure of choice in Scheuermann's kyphosis that is severe but flexible on hyperextension with a curve greater than 65 degrees. PMID:2295164

Otsuka, N Y; Hall, J E; Mah, J Y

1990-02-01

144

[Posterior thoracotomy in ventral decubitus].  

PubMed

The rigidity of the chest wall, thank to its bone framework, determines the variety of operative access in thoracic surgery, both thoracoscopic and open. The posterior thoracotomy on the bed of the resected rib in ventral decubitus is traditionally but gratuitously rarely used access. The method permits comfortable access to trachea, bifurcation, main bronchi and thoracic esophagus. It can also be used in cases of foregoing thoracothomy. Authors own the experience of 111 cases with the use of posterior thoracotomy in ventral decubitus. The access proved to be preferable for the operations on the membranous part of the trachea and main bronchi, some localizations of thoracic tracheoesophageal fistula. The access suggests fast mobilization of the root of the lung without foregoing pneumolisis, which is important in cases of pleural cavity obliteration after tuberculosis or pleural empyem. PMID:23715388

Parshin, V D; Grigir'eva, S P; Parshin, V V; Khetagurov, M A; Dydykin, S S; Laptina, V I

2013-01-01

145

Anterior and posterior ankle impingement.  

PubMed

Anterior ankle impingement is characterized by anterior ankle pain on activity. Recurrent (hyper) dorsiflexion is often the cause. Typically, there is pain on palpation at the anteromedial or anterolateral joint line. Some swelling or limitation in dorsiflexion are present. Plain radiographs can disclose the cause of the impingement. In the case of spurs or osteophytes, the diagnosis is anterior bony impingement. In the absence of spurs or osteophytes, the diagnosis is anterior soft tissue impingement. In patients with anteromedial impingement, plain radiographs ae often falsely negative. An oblique view (anteromedial impingement view = AMI view) is recommended in these patients. Arthroscopic management with removal of the offending tissue provides good to excellent long-term (5-8 years) results in 83% of patients with grade 0 and grade I lesions. Long-term results are good/excellent in 50% of patients with grade II lesions (osteophytes secondary to arthritis with joint space narrowing). In posterior ankle impingement, patients experience hindfoot pain when the ankle is forcedly plantarflexed. Trauma or overuse can be the cause. The trauma mechanism is hyperplantarflexion or a combined inversion plantarflexion injury. Overuse injuries typically occur in ballet dancers and downhill runners, who report pain on palpation at the posterolateral aspect of the talus. On plain radiographs, an os trigonum or hypertrophic posterior or talar process can be detected. Surgical management involves removal of the os trigonum, scar tissue, or hypertrophic posterior talar process. In the case of combined posterior bony impingement and flexor hallucis longus tendinopathy, a release of the flexor hallucis longus is performed simultaneously. Endoscopic management is associated with a low morbidity, a short recovery time, and provides good/excellent results at 2-5 years follow-up in 80% of patients. PMID:16971256

Niek van Dijk, C

2006-09-01

146

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

147

Markov chain Monte Carlo posterior sampling with the Hamiltonian method.  

SciTech Connect

A major advantage of Bayesian data analysis is that provides a characterization of the uncertainty in the model parameters estimated from a given set of measurements in the form of a posterior probability distribution. When the analysis involves a complicated physical phenomenon, the posterior may not be available in analytic form, but only calculable by means of a simulation code. In such cases, the uncertainty in inferred model parameters requires characterization of a calculated functional. An appealing way to explore the posterior, and hence characterize the uncertainty, is to employ the Markov Chain Monte Carlo technique. The goal of MCMC is to generate a sequence random of parameter x samples from a target pdf (probability density function), {pi}(x). In Bayesian analysis, this sequence corresponds to a set of model realizations that follow the posterior distribution. There are two basic MCMC techniques. In Gibbs sampling, typically one parameter is drawn from the conditional pdf at a time, holding all others fixed. In the Metropolis algorithm, all the parameters can be varied at once. The parameter vector is perturbed from the current sequence point by adding a trial step drawn randomly from a symmetric pdf. The trial position is either accepted or rejected on the basis of the probability at the trial position relative to the current one. The Metropolis algorithm is often employed because of its simplicity. The aim of this work is to develop MCMC methods that are useful for large numbers of parameters, n, say hundreds or more. In this regime the Metropolis algorithm can be unsuitable, because its efficiency drops as 0.3/n. The efficiency is defined as the reciprocal of the number of steps in the sequence needed to effectively provide a statistically independent sample from {pi}.

Hanson, Kenneth M.

2001-01-01

148

The posterior condylar angle in osteoarthritic knees  

Microsoft Academic Search

The posterior condylar angle is formed by the transepicondylar axis and the tangent line to the posterior condyles. It is an important relationship to determine rotational alignment of the femoral component in total knee arthroplasty. We measured this angle directly in 107 osteoarthritic knees undergoing total knee arthroplasty. The posterior condylar angle was significantly greater in valgus knees than in

Frankie M. Griffin; John N. Insall; Giles R. Scuderi

1998-01-01

149

Arachnoid cysts of the posterior fossa  

Microsoft Academic Search

BACKGROUNDThe surgical indications and management of posterior fossa arachnoid cysts (AC) are still controversial. Different surgical techniques and management have already been suggested for arachnoid cysts of the posterior fossa. AC involving the posterior fossa and especially the cerebellopontine angle may carry a high surgical morbidity because of the involvement of important neurovascular structures (e.g., brain stem and cranial nerves).

Madjid Samii; Gustavo A Carvalho; Martin U Schuhmann; Cordula Matthies

1999-01-01

150

Staple capsulorrhaphy for recurrent posterior shoulder dislocation  

Microsoft Academic Search

Recurrent posterior shoulder dislocation or subluxa tion is uncommon but occurs occasionally in athletes Ten patients were treated with a posterior shoulder staple capsulorrhaphy. A posterior Bankhart-type le sion was found in all cases. Eight of the 10 patients had pain relief. The range of motion was usually maintained postoperatively, but no patient returned to his former throwing status. Four

James E. Tibone; Carlos Prietto; Frank W. Jobe; Robert W. Kerlan; Vincent S. Carter; Clarence L. Shields; Stephen J. Lombardo; H. Royer Collins; Lewis A. Yocum

1981-01-01

151

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 ...

Jackson, Ms.

2008-03-24

152

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.

K-12 Outreach,

153

Networks for Evidential Probability  

Microsoft Academic Search

\\u000a In §4 we discussed two different semantics for Schema (1.1) to answer two different types of inferential question for the\\u000a theory of evidential probability. The first interpretation given to Schema (1.1) is just the usual semantics of evidential\\u000a probability, which we call first-order EP (§4.3.1). The second interpretation given to Schema (1.1) is a proposal to evaluate\\u000a the robustness of

Rolf Haenni; Jan-Willem Romeijn; Gregory Wheeler; Jon Williamson

154

Combined Posterior and Anterior Ankle Arthroscopy  

PubMed Central

Treatment of combined anterior and posterior ankle pathology usually consists of either combined anterior and posterior arthrotomies or anterior ankle arthroscopy with an additional posterolateral portal. The first technique bears the risk of complications associated with the extensive exposure, the latter technique provides limited access to the posterior ankle joint. A case is described of combined anterior and posterior arthroscopy, with the patient lying prone and then turned supine, addressing both anterior and posterior ankle pathologies in one tempo. This minimally invasive combined approach allows quick recovery and early return to work and sports activities.

Scholten, Peter E.; van Dijk, C. Niek

2012-01-01

155

Probability Sampling with Quotas  

Microsoft Academic Search

This paper describes certain quota sampling procedures and attempts to show that they are very close to traditional probability sampling. Quotas are shown to depend on availability for interviewing and evidence is presented to show that sex, age, and employment status are reasonable predictors of availability. Quota sampling methods are not unbiased but data are presented which suggest that the

Seymour Sudman

1966-01-01

156

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…

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

2012-01-01

157

Probability and Statistical Inference  

Microsoft Academic Search

These lectures introduce key concepts in probability and statistical\\u000ainference at a level suitable for graduate students in particle physics. Our\\u000agoal is to paint as vivid a picture as possible of the concepts covered.

Harrison B. Prosper

2006-01-01

158

Analytical Probability Theory.  

National Technical Information Service (NTIS)

Research results under the grant have been summarized in fifteen research articles, six of which have been published and the other nine of which have been submitted for publication. The research results are in the general area of analytic probability theo...

E. Lukacs

1969-01-01

159

Probable binary 3220 Murayama  

NASA Astrophysics Data System (ADS)

Lightcurve observations made from three stations during 2004 Nov. 7 to Dec. 17 have revealed that 3220 Murayama is a probable binary asteroid. Primary's rotation period: 4.8595±0.0011 hr, amplitude: 0.13-0.15 mag. Secondary-to-primary mean diameter ratio: 0.4. The orbital period is unclear.

Tsuchikawa, Akira; Miyasaka, Seidai; Hamanowa, Hiromi

2005-12-01

160

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

161

Estimation of Multinomial Probabilities.  

National Technical Information Service (NTIS)

This paper deals with the estimation of the parameters (cell probabilities) of a multinomial distribution. The maximum likelihood estimator (MLE) is known to be minimax and admissible with respect to a quadratic loss function. It is shown that the MLE is ...

K. Alam

1978-01-01

162

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.

Siegrist, Kyle

163

Reconstruction of Posterior Trunk Defects  

PubMed Central

The posterior trunk roughly encompasses the upper back from the shoulders to the lumbar area above the iliac crests. Long-term outcomes in the treatment of defects of the spine and bony thorax have been proved superior if flaps were used. Many local muscle and fasciocutaneous flaps are available alternatives. A guideline, patterned according to arbitrary anatomic territories of the back, is suggested as a starting point for the selection of appropriate primary and secondary flap options. Depending on flap availability, the latissimus dorsi and trapezius muscles are the workhorse flaps for the upper back, whereas perforator flaps have become a useful alternative for the lumbar region in lieu of free flaps.

Hallock, Geoffrey G.

2011-01-01

164

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

2012-01-24

165

Retrocausality and conditional probability  

NASA Astrophysics Data System (ADS)

Costa de Beauregard has proposed that physical causality be identified with conditional probability. That proposal is shown to be vulnerable on two accounts. The first, though mathematically trivial, seems to be decisive so far as the current formulation of the proposal is concerned. The second lies in a physical inconsistency which seems to have its source in a Copenhagenlike disavowal of realism in quantum mechanics.

Stuart, C. I. J. M.

1991-02-01

166

Subjective probabilities of interpersonal relationships  

Microsoft Academic Search

Subjective probabilities of the existence of various interpersonal relationships under various conditions were obtained with a questionnaire given male college students. Positive affective relationships were regarded as generally most probable, and negative affective relationships as least probable.\\

Clinton B. De Soto; James L. Kuethe

1959-01-01

167

Probability distributions for locations of calling animals, receivers, sound speeds, winds, and data from travel time differences  

NASA Astrophysics Data System (ADS)

A new nonlinear sequential Monte Carlo technique is used to estimate posterior probability distributions for the location of a calling animal, the locations of acoustic receivers, sound speeds, winds, and the differences in sonic travel time between pairs of receivers from measurements of those differences, while adopting realistic prior distributions of the variables. Other algorithms in the literature appear to be too inefficient to yield distributions for this large number of variables (up to 41) without recourse to a linear approximation. The new technique overcomes the computational inefficiency of other algorithms because it does not sequentially propagate the joint probability distribution of the variables between adjacent data. Instead, the lower and upper bounds of the distributions are propagated. The technique is applied to commonly encountered problems that were previously intractable such as estimating how accurately sound speed and poorly known initial locations of receivers can be estimated from the differences in sonic travel time from calling animals, while explicitly modeling distributions of all the variables in the problem. In both cases, the new technique yields one or two orders of magnitude improvements compared with initial uncertainties. The technique is suitable for accurately estimating receiver locations from animal calls.

Spiesberger, John L.

2005-09-01

168

Modeling Cloudy and Clear Interval Length Probabilities Using Space Shuttle Imagery.  

National Technical Information Service (NTIS)

Interval length probabilities provide an alternative to other characterizations of cloudy and clear regions as viewed from atop the atmosphere. This work attempts to accurately model these probabilities using very high resolution space shuttle orbiter ima...

G. F. Howard

1987-01-01

169

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

170

Arthroscopic posterior bone block: surgical technique.  

PubMed

Posterior glenohumeral instability remains a difficult problem. There are still many controversies regarding surgical treatment, due to a lack of understanding the pathomechanical issues leading to posterior instability. This article presents a new arthroscopic technique of posterior bone block augmentation, which we found to be effective, repeatable and successful. This technique can be used for combined soft tissue and bony defects as well as for revisions after previous soft tissue reconstructions. PMID:22910897

Lafosse, Laurent; Franceschi, Giorgio; Kordasiewicz, Bartlomiej; Andrews, Wade J; Schwartz, Daniel

2012-08-22

171

Posterior ankle impingement in the dancer.  

PubMed

Dancers spend a lot of time in the relevé position in demi-pointe and en pointe in their training and their careers. Pain from both osseous and soft tissue causes may start to occur in the posterior aspect of their ankle. This article reviews the potential causes of posterior ankle impingement in dancers. It will discuss the clinical evaluation of a dancer and the appropriate workup and radiographic studies needed to further evaluate a dancer with suspected posterior ankle impingement. PMID:22071398

Moser, Brad R

172

Intercostal nerve conduction and posterior rhizotomy in the diagnosis and treatment of thoracic radiculopathy  

Microsoft Academic Search

Intercostal nerve conduction study has proved to be an accurate technique in diagnosis of thoracic radiculopathy in 161 patients, 80 of whom had subsequent posterior rhizotomy with relief of pain in 81% of those undergoing surgery. The only significant complication of intercostal nerve conduction study is an 8·8% incidence of pneumothorax.

E. Ralph Johnson; Joe Powell; James Caldwell; Charles Crane

1974-01-01

173

Probabilities for Solar Siblings  

NASA Astrophysics Data System (ADS)

Abstract (2,250 Maximum Characters): 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. Bobylev,V.V., Bajkova, A.T., Mylläri, A. & Valtonen,M. 2011, Astronomy Letters 37, 550

Valtonen, Mauri; Myllari, A.; Bobylev, V. V.; Bajkova, A.

2013-05-01

174

Ganglion cyst on the posterior cruciate ligament: a case report  

PubMed Central

Objective: To present the diagnostic and clinical features of a ganglion cyst located on the posterior cruciate ligament and create awareness amongst clinicians of this uncommon diagnosis. Clinical Features: A 24-year old woman complaining of intermittent left knee pain brought on by an increase in mileage during her training for a half-marathon. A diagnosis of mild chondromalacia patella and a ganglion cyst on the posterior cruciate ligament was made via diagnostic imaging. Intervention and outcome: Patient was followed up with imaging. The patient chose to withdraw a surgical consult due to patient preference. No conservative treatment was provided. Conclusion: Although chondromalacia patella is the more probable, a secondary diagnostic consideration in this patient could be a ganglion cyst. A ganglion cyst on the posterior cruciate ligament is an uncommon diagnosis and the clinical manifestations are variable and non-specific. It is important to be aware of its clinical features and to obtain appropriate methods of imaging to generate the diagnosis promptly.

Durante, Jaclyn A.

2009-01-01

175

Task performance based on the posterior probability of maximum-entropy reconstructions obtained with MEMSYS 3  

Microsoft Academic Search

The authors previously described how image reconstruction algorithms can be evaluated on the basis of how well binary-discrimination tasks can be performed using the reconstructions. The test statistic in the detection task was the estimated activity within the object, also known as the non-prewhitening matched-filter output. This approximation to the likelihood function was used because a full characterization of the

Kyle J. Myers; Kenneth M. Hanson

1991-01-01

176

Task performance based on the posterior probability of maximum-entropy reconstructions obtained with MEMSYS 3  

Microsoft Academic Search

We have described previously132 how image reconstruction algorithms can be evaluated on the basis of how well binary-discrimination tasks can be performed using the reconstructions. The test statistic in the detection task was the estimated activity within the object, also known as the non-prewhitening matched- filter output. This approximation to the likelihood function was used because a full characterization of

K. J. Myers; K. M. Hanson

1991-01-01

177

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

178

RactIP: fast and accurate prediction of RNA-RNA interaction using integer programming  

PubMed Central

Motivation: Considerable attention has been focused on predicting RNA–RNA interaction since it is a key to identifying possible targets of non-coding small RNAs that regulate gene expression post-transcriptionally. A number of computational studies have so far been devoted to predicting joint secondary structures or binding sites under a specific class of interactions. In general, there is a trade-off between range of interaction type and efficiency of a prediction algorithm, and thus efficient computational methods for predicting comprehensive type of interaction are still awaited. Results: We present RactIP, a fast and accurate prediction method for RNA–RNA interaction of general type using integer programming. RactIP can integrate approximate information on an ensemble of equilibrium joint structures into the objective function of integer programming using posterior internal and external base-paring probabilities. Experimental results on real interaction data show that prediction accuracy of RactIP is at least comparable to that of several state-of-the-art methods for RNA–RNA interaction prediction. Moreover, we demonstrate that RactIP can run incomparably faster than competitive methods for predicting joint secondary structures. Availability: RactIP is implemented in C++, and the source code is available at http://www.ncrna.org/software/ractip/ Contact: ykato@kuicr.kyoto-u.ac.jp; satoken@k.u-tokyo.ac.jp Supplementary information: Supplementary data are available at Bioinformatics online.

Kato, Yuki; Sato, Kengo; Hamada, Michiaki; Watanabe, Yoshihide; Asai, Kiyoshi; Akutsu, Tatsuya

2010-01-01

179

Posterior tibial tendon rupture in athletic people  

Microsoft Academic Search

We present our findings in six athletic patients with a ruptured or partially ruptured posterior tibial tendon. Pain in the midarch region, difficulty pushing off while running, and a pronated flattened longitudinal arch are the usual symptoms and physical findings of this injury. Surgical treatment, including reattachment of the rup tured posterior tibial tendon, is effective in restoring some but

Lee Woods; Robert E. Leach

1991-01-01

180

Visual Field Defects in Deformational Posterior Plagiocephaly  

Microsoft Academic Search

Purpose: We sought to determine whether visual field abnormalities occur in infants with deformational posterior plagiocephaly and to assess whether there is a relationship between the severity and laterality of visual field abnormalities with the severity and laterality of skull deformity. Methods: A retrospective chart review was performed on 40 consecutive infants with deformational posterior plagiocephaly. Each was tested with

R. Michael Siatkowski; Aaron C. Fortney; Sayeda A. Nazir; Sterling L. Cannon; Jayesh Panchal; Paul Francel; William Feuer

181

[Echography in posterior scleritis (author's transl)].  

PubMed

Following a brief clinical description of posterior scleritis its echographical criteria are described with reference to a case history: broad scleral echos with high reflectivity and poor sound attenuation in the A-scan are characteristic, as well as clear demarcation of the thickened posterior sclera from the orbital tissue and edema in Tenon's space in the B-scan. PMID:7253515

Rochels, R; Reis, G

1980-11-01

182

Main posterior watershed zone of the choroid  

Microsoft Academic Search

The main posterior watershed zone of the choroid is located between the nasal edge of the optic disc and the fovea and represents the area situated between the territories supplied by the temporal and nasal posterior ciliary arteries. In the fluorescein angiographies of 800 normal subjects a watershed zone was not observed in 33.1% due to technical reasons and in

GIUSEPPE GIUFFRI

1989-01-01

183

Posterior Instrumentation for Occipitocervical Fusion  

PubMed Central

Since 1995, 29 consecutive patients with craniocervical spine instability due to several pathologies were managed with posterior occipitocervical instrumentation and fusion. Laminectomy was additionally performed in nineteen patients. The patients were divided in two groups: Group A which included patients managed with screw-rod instrumentation, and Group B which included patients managed with hook-and-screw-rod instrumentation. The patients were evaluated clinically and radiographically using the following parameters: spine anatomy and reconstruction, sagittal profile, neurologic status, functional level, pain relief, complications and status of arthrodesis. The follow-up was performed immediately postoperatively and at 2, 6, 12 months after surgery, and thereafter once a year. Fusion was achieved in all but one patient. One case of infection was the only surgery related complication. Neurological improvement and considerable pain relief occurred in the majority of patients postoperatively. There were neither intraoperative complications nor surgery related deaths. However, the overall death rate was 37.5% in group A, and 7.7% in group B. There were no instrument related failures. The reduction level was acceptable and was maintained until the latest follow-up in all of the patients. No statistical difference between the outcomes of screw-rod and hook-and-screw-rod instrumentation was detected. Laminectomy did not influence the outcome in either group. Screw-rod and hook-and-screw-rod occipitocervical fusion instrumentations are both considered as safe and effective methods of treatment of craniocervical instability.

Sapkas, George; Papadakis, Stamatios A; Segkos, Dimitrios; Kateros, Konstantinos; Tsakotos, George; Katonis, Pavlos

2011-01-01

184

Posterior instrumentation for occipitocervical fusion.  

PubMed

Since 1995, 29 consecutive patients with craniocervical spine instability due to several pathologies were managed with posterior occipitocervical instrumentation and fusion. Laminectomy was additionally performed in nineteen patients. The patients were divided in two groups: Group A which included patients managed with screw-rod instrumentation, and Group B which included patients managed with hook-and-screw-rod instrumentation. The patients were evaluated clinically and radiographically using the following parameters: spine anatomy and reconstruction, sagittal profile, neurologic status, functional level, pain relief, complications and status of arthrodesis. The follow-up was performed immediately postoperatively and at 2, 6, 12 months after surgery, and thereafter once a year. Fusion was achieved in all but one patient. One case of infection was the only surgery related complication. Neurological improvement and considerable pain relief occurred in the majority of patients postoperatively. There were neither intraoperative complications nor surgery related deaths. However, the overall death rate was 37.5% in group A, and 7.7% in group B. There were no instrument related failures. The reduction level was acceptable and was maintained until the latest follow-up in all of the patients. No statistical difference between the outcomes of screw-rod and hook-and-screw-rod instrumentation was detected. Laminectomy did not influence the outcome in either group. Screw-rod and hook-and-screw-rod occipitocervical fusion instrumentations are both considered as safe and effective methods of treatment of craniocervical instability. PMID:21772931

Sapkas, George; Papadakis, Stamatios A; Segkos, Dimitrios; Kateros, Konstantinos; Tsakotos, George; Katonis, Pavlos

2011-06-02

185

More accurate time from the Heathkit most accurate clock  

Microsoft Academic Search

The addition of an auxiliary circuit to the Heathkit GC-1000 clock is described. The circuit, which consists of two integrated circuits, two resistors, and three capacitors, will supply a more accurate timing pulse to the computer. The circuit contains two input signals and produces one output; the inputs are multiplexed seven-digit displays (two digits for hour, minute, and second, and

M. V. Tollefson; R. H. Bloomer Jr.

1986-01-01

186

Probability distributions for magnetotellurics  

SciTech Connect

Estimates of the magnetotelluric transfer functions can be viewed as ratios of two complex random variables. It is assumed that the numerator and denominator are governed approximately by a joint complex normal distribution. Under this assumption, probability distributions are obtained for the magnitude, squared magnitude, logarithm of the squared magnitude, and the phase of the estimates. Normal approximations to the distributions are obtained by calculating mean values and variances from error propagation, and the distributions are plotted with their normal approximations for different percentage errors in the numerator and denominator of the estimates, ranging from 10% to 75%. The distribution of the phase is approximated well by a normal distribution for the range of errors considered, while the distribution of the logarithm of the squared magnitude is approximated by a normal distribution for a much larger range of errors than is the distribution of the squared magnitude. The distribution of the squared magnitude is most sensitive to the presence of noise in the denominator of the estimate, in which case the true distribution deviates significantly from normal behavior as the percentage errors exceed 10%. In contrast, the normal approximation to the distribution of the logarithm of the magnitude is useful for errors as large as 75%.

Stodt, John A.

1982-11-01

187

Update on craniofacial surgery: the differential diagnosis of lambdoid synostosis/posterior plagiocephaly.  

PubMed

There has been an evolution of thought on the diagnosis and treatment of posterior plagiocephaly. Synostotic posterior plagiocephaly (lambdoid synostosis) can be diagnosed and differentiated from non-synostotic posterior plagiocephaly (positional molding) based on specific cosmetic and radiologic criteria. The advent of high-resolution three-dimensional CT analysis of cranial morphology combined with meticulous clinical studies of the two major causes of posterior plagiocephaly has added much to our understanding of this skull deformity. Children with lambdoid synostosis have a trapezoid-shaped skull with posterior displacement of their ipsilateral ear, ipsilateral mastoid bossing, contralateral occipital bossing, and a fused lambdoid suture that appears as a ridge. Children with posterior plagiocephaly without lambdoid synostosis have a characteristic parallelogram-shaped skull with anterior displacement of the ipsilateral ear and ipsilateral frontal bossing. This subject is surrounded in controversy because many of the children in the past thought to have lambdoid synostosis probably did not, based in part on the aforementioned specific criteria. This is an important point, as most patients with posterior plagiocephaly without synostosis will improve without surgery. One should thus be appropriately conservative in the selection of patients for surgery. The majority of infants evaluated at craniofacial clinics presumably have posterior plagiocephaly without synostosis and can be successfully treated with frequent head turning, helmet, or band therapy. Patients with clinically and radiologically proven synostotic posterior plagiocephaly and a severe deformity should undergo craniofacial surgery. The technique of biparieto-occipital craniotomy is safe, simple, and delivers a good cosmetic result. Our postoperative photographic evaluations have shown an immediate, aesthetically pleasing change in the contour of the occiput, which tends to improve with time. PMID:11197708

Ellenbogen, R G; Gruss, J S; Cunningham, M L

2000-01-01

188

Anterior Commissure - Posterior Commissure Revisited  

PubMed Central

Objective The anterior commissure (AC) and posterior commissure (PC) are the two distinct anatomic structures in the brain which are difficult to observe in detail with conventional MRI, such as a 1.5T MRI system. However, recent advances in ultra-high resolution MRI have enabled us to examine the AC and PC directly. The objective of the present study is to standardize the shape and size of the AC and PC using a 7.0T MRI and to propose a new brain reference line. Materials and Methods Thirty-four, 21 males and 13 females, healthy volunteers were enrolled in this study. After determining the center of each AC and PC, we defined the connection of these centers as the central intercommissural line (CIL). We compared the known extra- and intra-cerebral reference lines with the CIL to determine the difference in the angles. Additionally, we obtained horizontal line from flat ground line of look front human. Results The difference in angle of the CIL and the tangential intercommissural line (TIL) from the horizontal line was 8.7 ± 5.1 (11 ± 4.8) and 17.4 ± 5.2 (19.8 ± 4.8) degrees in males and females, respectively. The difference in angle between the CIL and canthomeatal line was 10.1 in both male and female, and there was no difference between both sexes. Likewise, there was no significant difference in angle between the CIL and TIL between both sexes (8.3 +/- 1.1 in male and 8.8 +/- 0.7 in female). Conclusion In this study, we have used 7.0T MRI to define the AC and PC quantitatively and in a more robust manner. We have showed that the CIL is a reproducible reference line and serves as a standard for the axial images of the human brain.

Choi, Sang-Han; Chi, Je-Geun; Kim, Young-Bo

2013-01-01

189

Probability learning as a function of momentary reinforcement probability1  

PubMed Central

Pigeons were trained on a probability learning task where the overall reinforcement probability was 0.50 for each response alternative but where the momentary reinforcement probability differed and depended upon the outcome of the preceding trial. In all cases, the maximum reinforcement occurred with a “win-stay, lose-shift” response pattern. When both position and color were relevant cues, the optimal response pattern was learned when the reinforcement probability for repeating the just-reinforced response was 0.80 but not when the probability was 0.65. When only color was relevant, learning occurred much more slowly, and only for subjects trained on large fixed ratio requirements.

Williams, Ben A.

1972-01-01

190

Physical Constructivism and Quantum Probability  

NASA Astrophysics Data System (ADS)

I describe the main ideas of constructive physics and its role for the probability interpretation of quantum theory. It is shown how the explicit probability space for quantum systems gives the formal representation of entanglement and decoherence.

Ozhigov, Yu. I.

2009-03-01

191

Contamination Probability of Order Statistics.  

National Technical Information Service (NTIS)

Given that an arbitrary number of observations are contaminated, explicity expressions are obtained for the probability of the ith smallest observation in the sample to be the jth smallest contaminated one. The probabilities are tabulated for the cases up...

V. K. Murthy

1975-01-01

192

Accurate measurements in volume data  

Microsoft Academic Search

An algorithm for very accurate visualization of an iso- surface in a 3D medical dataset has been developed in the past few years. This technique is extended in this paper to several kinds of measurements in which exact geometric information of a selected iso-surface is used to derive volume, length, curvature, connectivity and similar geometric information from an object of

Javier Olivan; Marco K. Bosma; Jaap Smit; S. K. Mun

2001-01-01

193

Method of accurizing rail guns  

Microsoft Academic Search

In space, projectiles with hypervelocity can deliver large amounts of energy to the target. Long range and high accuracy are essential. This report presents a method of improving the accuracy of hypervelocity vehicles by measuring the output velocity and correcting the direction by impulse from a laser beam normal to the projectile flight path. The accurizer is described, trajectory-correction calculations

Farnum

1984-01-01

194

Accurate, inexpensive, thermal expansion microtranslator  

Microsoft Academic Search

We have developed an accurate, inexpensive translator utilizing the thermal expansion of an electrically heated wire. The resistance of the wire, measured in a Wheatstone bridge, provides a readout of the length of the wire based on its temperature coefficient of resistance.

James J. Snyder

1993-01-01

195

Negative probabilities and measurement disturbance  

Microsoft Academic Search

Feynman once said that ``the only difference between a probabilistic classical world and the equations of the quantum world is that somehow or other it appears as if the probabilities would have to go negative''. But what is the essential reason for probabilities going negative? Here it is demonstrated that negative probabilities are a direct consequence of measurement disturbance. The

Lars M. Johansen

2008-01-01

196

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

197

A Posterior Petrous Meningioma with Recurrent Vertigo  

PubMed Central

Meningioma's account for around 15% of all primary brain tumors with some 10% of meningiomas arising in the posterior fossa. In rare cases, a meningioma can form around the endolymphatic sac. When formed in the posterior fossa, meningioma tumors can produce vague, non-specific vertiginous symptoms. Research has observed that a subset of these lesions could produce symptoms indistinguishable from those of Meniere's disease. Therefore, we described the clinical features of a case of posterior petrous meningioma with recurrent vertigo as well as the substantial resolution of symptoms after tumor removal via transmastoid approach.

Choi, Seong Jun; Lee, Jong Bin; Bae, Joon-Ho; Yoon, Jung-Hee; Lee, Ho-Jin; Kim, Chan-Ho; Park, Keehyun

2012-01-01

198

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

2011-02-16

199

Central posterior capsule pigmentation in a patient with pigment dispersion and previous ocular trauma: A case report  

PubMed Central

We report a 55-year-old man with unusually dense, unilateral central posterior capsule pigmentation associated with the characteristic clinical features of pigment dispersion syndrome, including a Krukenberg's spindle and dense trabecular pigmentation in both eyes. A history of an old blunt ocular trauma probably caused separation of the anterior hyaloid from the back of the lens, thereby creating an avenue by which pigment could reach the potential space of Berger's from the posterior chamber.

Al-Mezaine, Hani S

2010-01-01

200

Evidence-based medicine in otolaryngology, Part 3: everyday probabilities: diagnostic tests with binary results.  

PubMed

Recent studies have demonstrated that the majority of physicians cannot accurately determine the predictive values of diagnostic tests. Physicians must understand the predictive probabilities associated with diagnostic testing in order to convey accurate information to patients, a key aspect of evidence-based practice. While sensitivity and specificity are widely understood, predictive values require a further understanding of conditional probabilities, pretest probabilities, and the prevalence of disease. Therefore, this third installment of the series "Evidence-Based Medicine in Otolaryngology" focuses on understanding the probabilities needed to accurately convey the results of dichotomous diagnostic tests in everyday practice. PMID:22588733

Shin, Jennifer J; Stinnett, Sandra; Page, John; Randolph, Gregory W

2012-05-15

201

Teaching NeuroImages: Ectopic posterior pituitary.  

PubMed

Ectopic posterior pituitary results from incomplete caudal extension of the diencephalon during embryogenesis.(1) The portal circulation carrying hypothalamic-releasing hormones to the adenohypophysis is disrupted, resulting in growth hormone deficiency and more rarely panhypopituitarism. PMID:24127194

Grech, Rueben; Galvin, Leo; Looby, Seamus; O'Hare, Alan; Thornton, John; Brennan, Paul

2013-10-15

202

Cerebellar mutism following posterior fossa tumour surgery.  

PubMed

Two cases of transient mutism following operative removal of cerebellar medulloblastoma are reported. These add to the few cases reported in the literature of this rare complication of posterior fossa tumour surgery in children. PMID:8861318

Jones, S; Kirollos, R W; Van Hille, P T

1996-04-01

203

Multiple acute infarcts in the posterior circulation  

Microsoft Academic Search

OBJECTIVE--to evaluate clinical, radiological, and prognostic features of patients with multiple acute infarcts in remote arterial territories of the posterior circulation. DESIGN--Data analysis from a prospective acute stroke registry in a community based primary care centre using a standard protocol including MRI and MRA. RESULTS--In three and a half years, 27 of the 236 patients (11%) with posterior circulation stroke

A Bernasconi; J Bogousslavsky; C Bassetti; F Regli

1996-01-01

204

Evaluation and Management of Posterior Shoulder Instability  

PubMed Central

Context: Posterior shoulder instability is a commonly misdiagnosed disorder in many competitive athletes. Type of Study: Clinical review. Evidence Acquisition: Relevant studies on posterior shoulder instability from 1950 to 2010 in PubMed and Cochrane databases were reviewed. Results: A total of 107 studies were reviewed. Conclusion: Patients who have undergone at least 6 months of physical therapy and still experience instability symptoms should be considered for surgical stabilization directed at their underlying pathology.

Tannenbaum, Eric; Sekiya, Jon K.

2011-01-01

205

Delayed primary realignment of posterior urethral rupture.  

PubMed

The treatment of acute posterior urethral rupture is controversial. Twelve patients who presented with acute posterior urethral rupture over a five-year period were treated by delayed primary realignment of the injury. The technique of this procedure and the outcome are the subject of this presentation. Eight patients had successful realignment without strictures. Two patients with strictures responded to simple dilatations with bougies and the other two had formal urethroplasty. PMID:14529221

Shittu, O B; Okeke, L I; Kamara, T B; Adebayo, S A

2003-06-01

206

Accurate Accident Reconstruction in VANET  

Microsoft Academic Search

\\u000a We propose a forensic VANET application to aid an accurate accident reconstruction. Our application provides a new source\\u000a of objective real-time data impossible to collect using existing methods. By leveraging inter-vehicle communications, we compile\\u000a digital evidence describing events before, during, and after an accident in its entirety. In addition to sensors data and\\u000a major components’ status, we provide relative positions

Yuliya Kopylova; Csilla Farkas; Wenyuan Xu

207

Arthroscopic capsular plication for posterior shoulder instability.  

PubMed

Seventeen patients with recurrent posterior shoulder instability underwent posterior capsular plication with or without suture anchors, between 1990 and 1992. Minimum 2-year follow-up was available for 14 patients (average, 33 months; range, 24 to 45 months). The etiology involved trauma in 9 cases, recurrent microtrauma in 4 cases, and no trauma in 1 case. Posterior capsular laxity was present in all 14 cases and was believed to be the primary pathology, although 12 patients showed some form of labral pathology. The patients were interviewed and assessed in six categories: pain, strength, function, stability, range-of-motion, and satisfaction. Twelve patients had excellent results and 2 had fair results. Nine of 10 patients who participate in recreational or competitive athletics reported full return to their preinjury level of function in their respective sports. There was one recurrence of posterior shoulder instability which was remedied with a second arthroscopic posterior capsular reconstruction. All 14 patients were satisfied with the results of their surgery, and no complications were noted. Capsular plication is a promising technique in the treatment of recurrent posterior shoulder instability. PMID:9531126

Wolf, E M; Eakin, C L

1998-03-01

208

More accurate time from the Heathkit most accurate clock  

NASA Astrophysics Data System (ADS)

The addition of an auxiliary circuit to the Heathkit GC-1000 clock is described. The circuit, which consists of two integrated circuits, two resistors, and three capacitors, will supply a more accurate timing pulse to the computer. The circuit contains two input signals and produces one output; the inputs are multiplexed seven-digit displays (two digits for hour, minute, and second, and one for tenths of a second) and the output appears as a string of about 10 low-going pulses about 1.25 ms in duration. Low pass filters (R1 and C1) are utilized to eliminate extraneous pulses. The materials and procedures for attaching the circuit to the clock are examined. The software for the data set ready signal, and the method for accurate timing of data collection are discussed. The accuracy of the clock is evaluated and it is observed that the circuit improves the correct time provided by the clock from + or - 29 ms to + or - 5 ms.

Tollefson, M. V.; Bloomer, R. H., Jr.

1986-05-01

209

Subjective Probabilities in Household Surveys.  

PubMed

Subjective probabilities are now collected on a number of large household surveys with the objective of providing data to better understand inter-temporal decision making. Comparison of subjective probabilities with actual outcomes shows that the probabilities have considerable predictive power in situations where individuals have considerable private information such as survival and retirement. In contrast the subjective probability of a stock market gain varies greatly across individuals even though no one has private information and the outcome is the same for everyone. An explanation is that there is considerable variation in accessing and processing information. Further, the subjective probability of a stock market gain is considerably lower than historical averages, providing an explanation for the relatively low frequency of stock holding. An important research objective will be to understand how individuals form their subjective probabilities. PMID:21643535

Hurd, Michael D

2009-06-01

210

An accurate iris location method for low quality iris images  

NASA Astrophysics Data System (ADS)

Iris location plays an important role in iris recognition system. Traditional iris location methods based on canny operator and integro-differential operator are affected by reflections, illumination inconsistency and eyelash. In this paper, we introduce an accurate iris location method for low quality iris images. First, a reflection removal method is used to interpolate the specular reflection. Then, we utilize Probable boundary (Pb) edge detection operator to detect papillary boundary with a lower interference point. Moreover, we optimize the Hough transform to obtain high accuracy result. Experimental results demonstrate that the location results of the proposed method are more accurate than other methods.

Wang, Ning; Li, Qiong; Abd El-Latif, Ahmed A.; Zhang, Tiejun; Peng, Jialiang

2012-04-01

211

38 CFR 4.46 - Accurate measurement.  

Code of Federal Regulations, 2013 CFR

...RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement...examinations conducted within the Department of Veterans Affairs. Muscle atrophy must also be accurately measured and reported....

2013-07-01

212

Quantum probability and comparative cognition.  

PubMed

Evolution would favor organisms that can make recurrent decisions in accordance with classical probability (CP) theory, because such choices would be optimal in the long run. This is illustrated by the base-rate fallacy and probability matching, where nonhumans choose optimally but humans do not. Quantum probability (QP) theory may be able to account for these species differences in terms of orthogonal versus nonorthogonal representations. PMID:23673034

Grace, Randolph C; Kemp, Simon

2013-06-01

213

Is vertebral artery hypoplasia a predisposing factor for posterior circulation cerebral ischemic events? A comprehensive review.  

PubMed

Vertebral artery hypoplasia is not currently considered an independent risk factor for stroke. Emerging evidence suggest that vertebral artery hypoplasia may contribute to posterior circulation ischemic events, especially when other risk factors coexist. In the present literature review, we present published data to discuss the relationship between a hypoplastic vertebral artery and posterior circulation cerebral ischemia. Despite difficulties and controversies in the accurate definition and prevalence estimation of vertebral artery hypoplasia, ultrasound studies reveal that the reduced blood flow observed ipsilateral to the hypoplastic vertebral artery may result in local cerebral hypoperfusion and subsequent focal neurological symptomatology. That risk of cerebral ischemia is related to the severity of the hypoplasia, suggesting that the smaller of paired arteries are more vulnerable to occlusion. Existing cohort studies further support clinical observations that hypoplastic vertebral artery enhances synergistically the vascular risk for posterior circulation ischemic events and is closely associated with both atherosclerotic and prothrombotic processes. PMID:23816871

Katsanos, Aristeidis H; Kosmidou, Maria; Kyritsis, Athanassios P; Giannopoulos, Sotirios

2013-06-26

214

Posterior subluxation of the glenohumeral joint.  

PubMed

Twenty-four patients who had posterior subluxation of the glenohumeral joint were assigned to one of two groups on the basis of the severity of the symptoms. The sixteen patients in Group I, who had less severe symptoms, were treated with a physical therapy program that was based on exercises to strengthen muscles. The eleven patients in Group II (three of whom had no success with physical therapy when they were originally in Group I) had a posterior capsulorrhaphy, with or without a bone block. According to an over-all rating, Group I had a rate of success of 63 per cent, and Group II had a rate of success of 91 per cent. The patients who had more severe ligamentous laxity were not more likely to fail either of the treatment programs. Although voluntary subluxation may be a subtle but important indicator of underlying emotional difficulties, it appears that, in the patient who is emotionally stable, the ability to voluntarily subluxate the shoulder posteriorly is not associated with a negative prognosis for either non-surgical or surgical treatment. Patients who have moderately disabling posterior subluxation of the shoulder should be treated with an intensive program that is designed to strengthen muscles. Patients who have symptoms that are severely disabling or who have had no success with non-operative treatment should be treated with posterior capsulorrhaphy. When the posterior aspect of the glenoid is severely deficient and when the posterior portion of the capsule or the infraspinatus tendon is attenuated, a bone block should augment the reconstruction. PMID:2918005

Fronek, J; Warren, R F; Bowen, M

1989-02-01

215

Posterior reversible encephalopathy syndrome in children with kidney diseases.  

PubMed

Posterior reversible encephalopathy syndrome (PRES) was originally used to describe a reversible, predominantly posterior leukoencephalopathy in patients who had renal insufficiency, hypertension, or who received immunosuppressive therapy. Since PRES is prevalent in children with kidney diseases, awareness and understanding of it is important for practicing pediatric nephrologists. A comprehensive approach to the diagnosis of PRES includes thorough determination of predisposing factors, clinical symptoms, and mandatory appropriate imaging. Unfortunately, the pathophysiology of PRES is still obscure and specificity of radiological examination has not yet been established. Two major predisposing factors, namely hypertension and calcineurin inhibitors, are well recognized. In addition, nephrotic syndrome is a common underlying condition for development of PRES. Frequent symptoms include altered consciousness (coma, stupor, lethargy, confusion), seizure, headache, and visual disturbance. Most of these symptoms usually develop abruptly and resolve within a few weeks after proper management. Cranial magnetic resonance (MR) imaging is the first-line modality of imaging studies for detecting PRES. Diffusion-weighted imaging with quantification of apparent diffusion coefficient (ADC) values by ADC mapping may provide more accurate and specific images in the future. PMID:21556718

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

2011-05-11

216

Involvement of the cervical cord and medulla in posterior reversible encephalopathy syndrome  

PubMed Central

The posterior reversible encephalopathy syndrome (PRES) is characterized by patchy cortical and subcortical lesions in the distribution of the posterior circulation. The lesions are classically reversible. This syndrome has multiple etiologies, most of which cause acute hypertension. We present a case of PRES with involvement of the medulla and cervical cord (apart from the typical parieto-occipital lesions)-an extremely rare imaging manifestation of PRES. It is important to recognize the imaging findings of PRES in spinal cord, and avoid misdiagnosis as myelitis by proper clinical correlation. Typically patients with myelitis have a profound neurodeficit, while patients with spinal manifestations of PRES are asymptomatic. Involvement of the cord in PRES has probably been an underrecognized entity as spinal imaging is not routinely performed in posterior reversible encephalopathy syndrome.

Choh, Naseer A.; Jehangir, Majid; Rasheed, Muddassir; Mira, Tajamul; Ahmad, Irfan; Choh, Suhil

2011-01-01

217

Probability Interpretation of Quantum Mechanics.  

ERIC Educational Resources Information Center

This paper draws attention to the frequency meaning of the probability concept and its implications for quantum mechanics. It emphasizes that the very meaning of probability implies the ensemble interpretation of both pure and mixed states. As a result some of the "paradoxical" aspects of quantum mechanics lose their counterintuitive character.…

Newton, Roger G.

1980-01-01

218

How to Elicit Many Probabilities  

Microsoft Academic Search

In building Bayesian belief networks, the elicitation of all probabilities required can be a major obstacle. We learned the extent of this often-cited observation in the construction of the probabilistic part of a complex influence diagram in the field of cancer treatment. Based upon our negative experiences with existing methods, we designed a new method for probability elicitation from domain

Linda C. Van Der Gaag; Silja Renooij; C. L. M. Witteman; B. M. P. Aleman; B. G. Taal

1999-01-01

219

Probability of sea level rise  

Microsoft Academic Search

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.

J. G. Titus; V. K. Narayanan

1995-01-01

220

From probabilities to Hamilton's principle  

NASA Astrophysics Data System (ADS)

It is shown that Hamilton's principle of classical mechanics can be derived from the relativistic invariance of the generalized spacetime Fisher information corresponding to the statistical description of results of measurement of the coordinates and the motion in space by means of the probability density and probability density current.

Kapsa, V.; Skála, L.

2009-08-01

221

Probability theory, not the very guide of life.  

PubMed

Probability theory has long been taken as the self-evident norm against which to evaluate inductive reasoning, and classical demonstrations of violations of this norm include the conjunction error and base-rate neglect. Many of these phenomena require multiplicative probability integration, whereas people seem more inclined to linear additive integration, in part, at least, because of well-known capacity constraints on controlled thought. In this article, the authors show with computer simulations that when based on approximate knowledge of probabilities, as is routinely the case in natural environments, linear additive integration can yield as accurate estimates, and as good average decision returns, as estimates based on probability theory. It is proposed that in natural environments people have little opportunity or incentive to induce the normative rules of probability theory and, given their cognitive constraints, linear additive integration may often offer superior bounded rationality. PMID:19839686

Juslin, Peter; Nilsson, Håkan; Winman, Anders

2009-10-01

222

Accurate Biomass Estimation via Bayesian Adaptive Sampling  

NASA Astrophysics Data System (ADS)

Typical estimates of standing wood derived from remote sensing sources take advantage of aggregate measurements of canopy heights (e.g. LIDAR) and canopy diameters (segmentation of IKONOS imagery) to obtain a wood volume estimate by assuming homogeneous species and a fixed function that returns volume. The validation of such techniques use manually measured diameter at breast height records (DBH). Our goal is to improve the accuracy and applicability of biomass estimation methods to heterogeneous forests and transitional areas. We are developing estimates with quantifiable uncertainty using a new form of estimation function, active sampling, and volumetric reconstruction image rendering for species specific mass truth. Initially we are developing a Bayesian adaptive sampling method for BRDF associated with the MISR Rahman model with respect to categorical biomes. This involves characterizing the probability distributions of the 3 free parameters of the Rahman model for the 6 categories of biomes used by MISR. Subsequently, these distributions can be used to determine the optimal sampling methodology to distinguish biomes during acquisition. We have a remotely controlled semi-autonomous helicopter that has stereo imaging, lidar, differential GPS, and spectrometers covering wavelengths from visible to NIR. We intend to automatically vary the way points of the flight path via the Bayesian adaptive sampling method. The second critical part of this work is in automating the validation of biomass estimates via using machine vision techniques. This involves taking 2-D pictures of trees of known species, and then via Bayesian techniques, reconstructing 3-D models of the trees to estimate the distribution moments associated with wood volume. Similar techniques have been developed by the medical imaging community. This then provides probability distributions conditional upon species. The final part of this work is in relating the BRDF actively sampled measurements to species and IKONOS imagery and the 3-D volume estimates. The combination of these then allow for a rapid and hopefully very accurate estimation of biomass.

Wheeler, K.; Knuth, K.; Castle, P.

2005-12-01

223

Assessing circular error probable when the errors are elliptical normal  

Microsoft Academic Search

An important problem of continuing interest to engineers is the need to assess the circular error probable (CEP), a measure of the impact accuracy of a projectile or a measure of GPS point positioning accuracy. One of the challenges in addressing this problem is to construct some accurate confidence bounds or intervals for CEP in the small sample settings, where

Jian Zhang; Weilian An

2011-01-01

224

Assessing circular error probable when the errors are elliptical normal  

Microsoft Academic Search

An important problem of continuing interest to engineers is the need to assess the circular error probable (CEP), a measure of the impact accuracy of a projectile or a measure of GPS point positioning accuracy. One of the challenges in addressing this problem is to construct some accurate confidence bounds or intervals for CEP in the small sample settings, where

Jian Zhang; Weilian An

2012-01-01

225

Application of sequential probability ratio test to uranium enrichment verification  

NASA Astrophysics Data System (ADS)

The sequential probability ratio test is a statistical process capable of quickly and accurately verifying the uranium enrichment in the header pipes of uranium centrifuge enrichment facilities. The test minimizes the time required for a measurement, making a complete verification possible in 15-30 min.

Pratt, J. C.; Close, D. A.

1987-08-01

226

Identification of Bayesian posteriors for coefficients of chaos expansions  

SciTech Connect

This article is concerned with the identification of probabilistic characterizations of random variables and fields from experimental data. The data used for the identification consist of measurements of several realizations of the uncertain quantities that must be characterized. The random variables and fields are approximated by a polynomial chaos expansion, and the coefficients of this expansion are viewed as unknown parameters to be identified. It is shown how the Bayesian paradigm can be applied to formulate and solve the inverse problem. The estimated polynomial chaos coefficients are hereby themselves characterized as random variables whose probability density function is the Bayesian posterior. This allows to quantify the impact of missing experimental information on the accuracy of the identified coefficients, as well as on subsequent predictions. An illustration in stochastic aeroelastic stability analysis is provided to demonstrate the proposed methodology.

Arnst, M. [210 KAP Hall, University of Southern California, Los Angeles, CA 90089 (United States)], E-mail: arnst@usc.edu; Ghanem, R. [210 KAP Hall, University of Southern California, Los Angeles, CA 90089 (United States); Soize, C. [Universite Paris-Est, Laboratoire de Modelisation et Simulation Multi-Echelle, MSME UMR8208 CNRS, 5 bd Descartes, Champs-sur-Marne, 77454 Marne-la-Vallee, Cedex 2 (France)

2010-05-01

227

Management of Posterior Fossa Dissecting Aneurysms  

PubMed Central

Summary Treatment and prognosis of 14 patients of posterior fossa arterial dissections (AD) and dissecting aneurysms (DA) in one institution was reviewed. Internal trapping of aneurysm was performed for six patients presenting with SAH (three Vertebral, one posterior cerebral, one posterior inferior cerebellar, one anterior inferior cerebellar DA). The patency of the parent arteries was preserved in four DA patients with SAH (two Vertebral, two Basilar DA), 1 incidental vertebral DA, and one DA patient with brainstem infarction using stents and coils (four patients) or coils only (two patient). Proximal occlusion of parent artery was performed in a vertebral DA with SAH. One patient with a superior cerebellar DA presented with a midbrain infarct developed SAH with spontaneous occlusion of the aneurysm two weeks later. Of the 14 cases, ten were angiographically stable or cured during a follow up period of four to 70 months. one spontaneously resolved and two recurred. There was one death.

Winston Chong, W. K.

2008-01-01

228

VATS left upper lobe posterior segmentectomy.  

PubMed

A 56-year-old male patient was admitted due to one small pulmonary nodule in the posterior segment of left upper lobe. Preoperative examinations showed no distant metastasis, pulmonary ventilation function and small airway function were highly damaged and could not tolerate lobectomy. Chest computed tomography (CT) showed one small pulmonary nodules on the posterior segment of left lung, which was considered to be early malignant lesions. In addition, no remarkably swollen lymph node was visible in the mediastinum. Therefore, video-assisted thoracic surgery (VATS) left upper lobe posterior segmentectomy was performed, and intraoperative frozen section confirmed the diagnosis of adenomatous hyperplasia of alveolar epithelial. Sequential dissection (or, single-direction approach) was applied in this surgery to avoid frequent turn-over of the lung lobes and shift of visual angle during the procedures. The Electric hook used in this surgery enables careful dissection and dissociation, with clear visual field and small blood loss. PMID:24040554

Xu, Meiqing; Liu, Changqing; Luo, Jing; Guo, Mingfa

2013-08-01

229

Posterior composite resin restorations: operative innovations.  

PubMed

The adhesive revolution is alleviating reservations regarding posterior composite resin restorations, established by past experience with outdated materials and techniques. Improved materials, instrumentation, and placement techniques have enhanced the performance of current formulations of posterior composite resins over their predecessors. However, it is a clinician's operative skill that ultimately determines the quality of a restorative option. The learning objective of this article is to share the author's experience in attaining adhesive excellence with posterior tooth-colored restorations as well as aesthetic anatomic form, minimal postoperative sensitivity, and a bond which can weather the true test of success-durability. Optimal applications, dental dam requirement, importance of the first increment of composite resin, restitution of occlusal morphology, and the clinical application are discussed. PMID:9242131

Liebenberg, W H

1996-10-01

230

VATS left upper lobe posterior segmentectomy  

PubMed Central

A 56-year-old male patient was admitted due to one small pulmonary nodule in the posterior segment of left upper lobe. Preoperative examinations showed no distant metastasis, pulmonary ventilation function and small airway function were highly damaged and could not tolerate lobectomy. Chest computed tomography (CT) showed one small pulmonary nodules on the posterior segment of left lung, which was considered to be early malignant lesions. In addition, no remarkably swollen lymph node was visible in the mediastinum. Therefore, video-assisted thoracic surgery (VATS) left upper lobe posterior segmentectomy was performed, and intraoperative frozen section confirmed the diagnosis of adenomatous hyperplasia of alveolar epithelial. Sequential dissection (or, single-direction approach) was applied in this surgery to avoid frequent turn-over of the lung lobes and shift of visual angle during the procedures. The Electric hook used in this surgery enables careful dissection and dissociation, with clear visual field and small blood loss.

Liu, Changqing; Luo, Jing; Guo, Mingfa

2013-01-01

231

Endoscopic endonasal ligation in treatment of severe posterior epistaxis.  

PubMed

The technique and indications of an endonasal endoscopic technique for treatment of posterior epistaxis are presented. Three cases were successfully treated in our department in 1999. The posterior vascularisation of the nose is reviewed with emphasis on surgical anatomy. Endoscopic endonasal ligation of posterior nasal arterial vascularisation is compared with other treatment choices in posterior epistaxis. The technique is save and efficient. Since it is also a minimally invasive technique, it has become our first choice surgical procedure for posterior epistaxis. PMID:10892504

Claes, J; Claes, G; Boudewyns, A N; Rombaux, P; Daele, J J

2000-01-01

232

Imaging findings in posterior instability of the shoulder  

Microsoft Academic Search

Posterior shoulder instability refers to the symptoms and signs resulting from excessive posterior translation of the humerus.\\u000a Magnetic resonance (MR) imaging is the radiological modality of choice in the diagnostic assessment of posterior instability.\\u000a Computed tomography (CT) is useful in the evaluation of osseous abnormalities associated with posterior instability. A detailed\\u000a description of the posterior osseous and labroligamentous abnormalities has

Srinivasan Harish; Arpit Nagar; Jaydeep Moro; David Pugh; Ryan Rebello; John O’Neill

2008-01-01

233

Posterior capsulitis of the temporomandibular joint.  

PubMed

Posterior capsulitis, which is characterized by pain and inflammation localized above and behind the condyle of the mandible, usually develops as a result of premature contacts in dental occlusion. The pain at the affected side is related to the severe spasm of M. Pterygoideus Lateralis or the splinting action of the masticatory muscles. This condition can be readily treated by occlusal grinding of these premature contacts after a definite diagnosis. The amount of grinding on the teeth varies according to the localization of premature contacts and the pain at the joint. This study covers 123 patients diagnosed as having posterior capsulitis and the results are presented. PMID:3088160

Or, S; Yücetas, S

1986-06-01

234

Posterior plica synechia: rare complication of adenotonsillectomy.  

PubMed

Tonsillectomy is one of the most common operations performed by otolaryngologists. Fever, otalgia, dehydration, sore throat, and hemorrhage are common complications. In this clinical report, a 7-year-old boy was presented with a synechia between the posterior plicae together with recurrence of adenoid hypertrophy after adenotonsillectomy 1 year previously. The synechia and adenoid were resected, and the patient was discharged from the hospital after 2 days. The complication in this case was most likely caused by traumatic injury of the posterior plicae during the previous tonsillectomy. This complication is, however, very rare. PMID:22801132

Çiçek, Mehmet T; Croo, Alexander; Kizilay, Ahmet

2012-07-01

235

[Hydatid cyst of the posterior fossa].  

PubMed

Hydatidosis is an endemic affection in Tunisia. Cerebral echinococcosis is a relatively rare entity accounting for only 1-2% of all hydatid cysts in humans. Extradural hydatid cyst of the posterior fossa is a very uncommon site for the disease. We report the case of a four-year-old child admitted for high intracranial pressure. Brain CT scan showed an extradural posterior fossa cyst without enhancement after contrast medium injection. Operative finding revealed a hydatid cyst. The histological examination of the tissue sample confirmed the diagnosis. The patient was given albendazole post operatively. She feels well six months later. PMID:17434701

Braham, E; Bellil, S; Bellil, K; Chelly, I; Mekni, A; Haouet, S; Kchir, N; Khaldi, M; Zitouna, M

2007-04-16

236

[Posterior fossa extradural and extracranial hydatid cyst].  

PubMed

Hydatidosis is an endemic disease in Morocco. Cerebral echinococcosis is a relatively rare entity accounting for only 1-2% of all hydatid cysts in humans. Extradural hydatid cyst of the posterior fossa is a very uncommon site for the disease: only four cases have been reported in the literature. We report the case of a 37-year-old admitted for high intracranial pressure. Brain MRI showed an extradural and extracranial posterior fossa cyst without enhancement after contrast medium injection. Multiple hydatid cysts were removed and the histological examination of the tissue sample confirmed the diagnosis. The patient was given albendazole postoperatively with good follow-up 6 months later. PMID:20138319

Lakhdar, F; Arkha, Y; Bougrine, M; Derraz, S; El Ouahabi, A; El Khamlichi, A

2010-02-06

237

Dialysis disequilibrium: another reversible posterior leukoencephalopathy syndrome?  

PubMed

Dialysis disequilibrium syndrome is a disorder of the central nervous system in patients on dialysis. The underlying etiology is thought to be primarily due to cerebral edema; however, neuroradiologic findings have not been described previously. We describe a patient who presented with new onset headaches and status epilepticus after beginning hemodialysis. Her neuroimaging studies revealed white matter changes in the posterior parietal and occipital lobes similar to those seen in patients with reversible posterior leukoencephalopathy syndrome (RPLS). This case suggests that dialysis disequilibrium syndrome and RPLS may represent a spectrum of disorders in which the underlying mechanism is vasogenic edema. PMID:12954540

Sheth, Kevin N; Wu, Gregory F; Messé, Steven R; Wolf, Ronald L; Kasner, Scott E

2003-09-01

238

Posterior-compartment repair: a urology perspective.  

PubMed

The prevalence of posterior-compartment prolapse (rectocele) is not known. The authors have found that operative repair symptomatically improved a majority of patients with impaired defecation associated with a large rectocele, but this improvement was likely related at least in part to factors other than the size of the rectocele. Multiple surgical techniques are available for rectocele repair, and the literature is not clear regarding indications for each type of surgical intervention. This article reviews the literature regarding various types of posterior-compartment repair, and draws conclusions regarding their absolute efficacy and relative efficacy in comparison with one another. PMID:22877720

Gomelsky, Alex; Dmochowski, Roger R

2012-08-01

239

Probable Inference and Quantum Mechanics  

SciTech Connect

In its current very successful interpretation the quantum theory is fundamentally statistical in nature. Although commonly viewed as a probability amplitude whose (complex) square is a probability, the wavefunction or state vector continues to defy consensus as to its exact meaning, primarily because it is not a physical observable. Rather than approach this problem directly, it is suggested that it is first necessary to clarify the precise role of probability theory in quantum mechanics, either as applied to, or as an intrinsic part of the quantum theory. When all is said and done the unsurprising conclusion is that quantum mechanics does not constitute a logic and probability unto itself, but adheres to the long-established rules of classical probability theory while providing a means within itself for calculating the relevant probabilities. In addition, the wavefunction is seen to be a description of the quantum state assigned by an observer based on definite information, such that the same state must be assigned by any other observer based on the same information, in much the same way that probabilities are assigned.

Grandy, W. T. Jr. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82070 (United States)

2009-12-08

240

Flail P2 cusp of posterior mitral valve leaflet demonstrated on multi-slice computed tomography.  

PubMed

We report a case of flail mitral valve in an elderly man. Contrast enhanced images of the left ventricle were compared with transthoracic echocardiography. MSCT during systolic phase accurately identified the flail P2 cusp of posterior mitral valve leaflet. It can be performed non-invasively without requiring sophisticated software. Our case suggests that MSCT may have a role in preoperative assessment of coronary arteries and mitral valve apparatus before mitral valve surgery. PMID:17052789

Wong, Teck Wee; De Larrazabal, Catherine; Boey, H Khim; Lim, Michael C L

2006-10-17

241

Clinical simulation using context-sensitive temporal probability models.  

PubMed Central

We present a language for representing context-sensitive temporal probabilistic knowledge. Context constraints allow inference to be focused on only the relevant portions of the probabilistic knowledge. We provide a declarative semantics for our language and an implemented algorithm (BNG) that generates Bayesian networks to compute the posterior probabilities of queries. We illustrate the use of the BNG system by applying it to the problem of modeling the effects of medications and other interventions on the condition of a patient in cardiac arrest.

Haddawy, P.; Helwig, J. W.; Ngo, L.; Krieger, R. A.

1995-01-01

242

Finding the maximum a posteriori probability (MAP) in a Bayesian taxonomic key is NP-hard  

Microsoft Academic Search

As an alternative to dichotomous keys, tabular keys are used for taxonomic identification. With the use of computers, keys based on the Bayes formula can also be made available more widely. For the development of a key, the maximum a posterior probability (MAP) for a taxon is important because it allows to evaluate the quality of a key. If it

Urs Fischbacher

1996-01-01

243

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

2007-09-25

244

Probability Distribution of Irradiance Scintillation.  

National Technical Information Service (NTIS)

We calculated the probability distribution function (PDF) from simulations. The simulations were of an initially spherical wave propagated through homogeneous atmospheric turbulence. The onset of strong scintillation was calculated. The simulations' PDFs ...

R. J. Hill R. G. Frehlich W. D. Otto

1997-01-01

245

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.

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

2012-01-01

246

Choice Probabilities and Choice Functions.  

National Technical Information Service (NTIS)

Although there are sizable literatures on the connections between choice probabilities and preference relations, and between preference relations and choice functions, little has been done--apart from their common ties to preference relations--to connect ...

P. C. Fishburn

1978-01-01

247

Probabilities Don't Matter  

Microsoft Academic Search

It is suggested that probabilities need not apply at all to matter in the\\u000aphysical world, which may be entirely described by the amplitudes given by the\\u000aquantum mechanical state. Instead, probabilities may apply only to conscious\\u000aperceptions in the mental world. Such perceptions may not form unique sequences\\u000athat one could call individual minds.

Don N. Page

1994-01-01

248

Transition Probabilities of Gd I  

Microsoft Academic Search

Rare earth transition probabilities are needed within the astrophysics community to determine rare earth abundances in stellar photospheres. The current work is part an on-going study of rare earth element neutrals. Transition probabilities are determined by combining radiative lifetimes measured using time-resolved laser-induced fluorescence on a slow atom beam with branching fractions measured from high resolution Fourier transform spectra. Neutral

Katherine Bilty; J. E. Lawler; E. A. Den Hartog

2011-01-01

249

Joint probabilities and quantum cognition  

NASA Astrophysics Data System (ADS)

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.

de Barros, J. Acacio

2012-12-01

250

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

251

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

252

Posterior reversible encephalopathy syndrome following measles vaccination  

Microsoft Academic Search

Due to recent domestic measles outbreaks in Japan, the Japanese government has mandated measles vaccination at ages 14 and 17 since April 2008. Since then, the number of people receiving measles vaccination has increased in Japan. Measles vaccination may cause serious neurological complications including encephalopathy, although the incidence is very low. We report here an adult case of posterior reversible

Tadanori Hamano; Tomoko Takeda; Hiroshi Morita; Tomoko Muramatsu; Makoto Yoneda; Hirohiko Kimura; Masaru Kuriyama

2010-01-01

253

[Posterior-reversible encephalopathy in hemodialysis].  

PubMed

Posterior-reversible encephalopathy syndrome (PRES) is a recently clinicoradiologic entity caused by numerous medical conditions and characterized by acute-neurologic disorders, such as headaches, confusion, seizures associated with arterial hypertension. MRI characteristics are typical. The rapid diagnosis is of capital importance due to a potential reversibility. PMID:18672415

Mahi, Mohamed; Mohamed, Benyahia; Toufiq, Aatif; Souad, Chaouir; Mohamed, Benameur

2008-07-30

254

MRI of the fetal posterior fossa  

Microsoft Academic Search

MRI is a useful tool to complement US for imaging of the fetal posterior fossa (PF). In France, the discovery of a PF malformation in the fetus frequently leads to termination of pregnancy (80% in a personal series). However, despite improved accuracy in the diagnosis of PF abnormalities, prognosis remains uncertain. The first objective of this review is to document

Catherine Adamsbaum; Marie Laure Moutard; Christine André; Valérie Merzoug; Solène Ferey; Marie Pierre Quéré; Fanny Lewin; Catherine Fallet-Bianco

2005-01-01

255

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

256

Space Coding in Primate Posterior Parietal Cortex  

Microsoft Academic Search

Neuropsychological studies of patients with lesions of right frontal (premotor) or posterior parietal cortex often show severe impairments of attentive sensorimotor behavior. Such patients frequently manifest symptoms like hemispatial neglect or extinction. Interestingly, these behavioral deficits occur across different sensory modalities and are often organized in head- or body-centered coordinates. These neuropsychological data provide evidence for the existence of a

Frank Bremmer; Anja Schlack; Jean-René Duhamel; Werner Graf; Gereon R. Fink

2001-01-01

257

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

258

Extradural dermoid tumours of the posterior fossa  

Microsoft Academic Search

Dermoid tumours in children usually occur in two locations: at the anterior fontanelle and on the occipital squama. An exceptional site of origin for a posterior fossa dermoid cyst is the extradural space. There are only six previous cases of this situation reported in the literature. A series of 103 subscalp and calvarial masses in children were reviewed and three

J F Martínez-Lage; J Ramos; A Puche; M Poza

1997-01-01

259

Gibbs sampling for marginal posterior expectations  

Microsoft Academic Search

In earlier work (Gelfand and Smith, 1990 and Gelfand et al, 1990) a sampling based approach using the Gibbs sampler was offered as a means for developing marginal posterior densities for a wide range of Bayesian problems several of which were previously inaccessible. Our purpose here is two-fold. First we flesh out the implementation of this approach for calculation of

Alan E. Gelfand; Adrian F. M. Smith

1991-01-01

260

Transition Probabilities of Gd I  

NASA Astrophysics Data System (ADS)

Rare earth transition probabilities are needed within the astrophysics community to determine rare earth abundances in stellar photospheres. The current work is part an on-going study of rare earth element neutrals. Transition probabilities are determined by combining radiative lifetimes measured using time-resolved laser-induced fluorescence on a slow atom beam with branching fractions measured from high resolution Fourier transform spectra. Neutral rare earth transition probabilities will be helpful in improving abundances in cool stars in which a significant fraction of rare earths are neutral. Transition probabilities are also needed for research and development in the lighting industry. Rare earths have rich spectra containing 100's to 1000's of transitions throughout the visible and near UV. This makes rare earths valuable additives in Metal Halide - High Intensity Discharge (MH-HID) lamps, giving them a pleasing white light with good color rendering. This poster presents the work done on neutral gadolinium. We will report radiative lifetimes for 135 levels and transition probabilities for upwards of 1500 lines of Gd I. The lifetimes are reported to ±5% and the transition probabilities range from 5% for strong lines to 25% for weak lines. This work is supported by the National Science Foundation under grant CTS 0613277 and the National Science Foundation's REU program through NSF Award AST-1004881.

Bilty, Katherine; Lawler, J. E.; Den Hartog, E. A.

2011-01-01

261

Accurate ab Initio Spin Densities  

PubMed Central

We present an approach for the calculation of spin density distributions for molecules that require very large active spaces for a qualitatively correct description of their electronic structure. Our approach is based on the density-matrix renormalization group (DMRG) algorithm to calculate the spin density matrix elements as a basic quantity for the spatially resolved spin density distribution. The spin density matrix elements are directly determined from the second-quantized elementary operators optimized by the DMRG algorithm. As an analytic convergence criterion for the spin density distribution, we employ our recently developed sampling-reconstruction scheme [J. Chem. Phys.2011, 134, 224101] to build an accurate complete-active-space configuration-interaction (CASCI) wave function from the optimized matrix product states. The spin density matrix elements can then also be determined as an expectation value employing the reconstructed wave function expansion. Furthermore, the explicit reconstruction of a CASCI-type wave function provides insight into chemically interesting features of the molecule under study such as the distribution of ? and ? electrons in terms of Slater determinants, CI coefficients, and natural orbitals. The methodology is applied to an iron nitrosyl complex which we have identified as a challenging system for standard approaches [J. Chem. Theory Comput.2011, 7, 2740].

2012-01-01

262

How accurate is peer grading?  

PubMed

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

Freeman, Scott; Parks, John W

2010-01-01

263

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.

Parks, John W.

2010-01-01

264

Ultrahighly accurate 3D profilometer  

NASA Astrophysics Data System (ADS)

We have developed an Ultrahigh-Accurate 3-D Profilometer (UA3P), which, using a new, in-house-developed atomic force probe, has an accuracy of 10 nm. It is capable of measuring corners as small as 2 micro meter in radius and can cover an area up to 400 x 400 x 90 (mm), providing a powerful boost to nano-level processing. A commercial product was introduced in 1994. Examples of the key components made possible by this technology include aspherical lenses (used for a Blu-ray Disc device, a next-generation DVD, digital cameras, cellular phones, optical communications), free form lenses (used for frennel lens common to CD and DVD, laser printer lens, multi focus glass lens, cubic phase plate to extend depth of focus), gigabit semiconductor wafers, hard discs, air conditioner scroll vanes, DVC cylinders. The premiere ultra high-precision three-dimensional profilometer delivers superb performance using a variety of micro-measurements for a wide range of applications.

Tsutsumi, Hideki; Yoshizumi, Keiichi; Takeuchi, Hiroyuki

2005-02-01

265

Model estimates hurricane wind speed probabilities  

NASA Astrophysics Data System (ADS)

In the United States, intense hurricanes (category 3, 4, and 5 on the Saffir/Simpson scale) with winds greater than 50 m s -1 have caused more damage than any other natural disaster [Pielke and Pielke, 1997]. Accurate estimates of wind speed exceedance probabilities (WSEP) due to intense hurricanes are therefore of great interest to (re)insurers, emergency planners, government officials, and populations in vulnerable coastal areas.The historical record of U.S. hurricane landfall is relatively complete only from about 1900, and most model estimates of WSEP are derived from this record. During the 1899-1998 period, only two category-5 and 16 category-4 hurricanes made landfall in the United States. The historical record therefore provides only a limited sample of the most intense hurricanes.

Mumane, Richard J.; Barton, Chris; Collins, Eric; Donnelly, Jeffrey; Eisner, James; Emanuel, Kerry; Ginis, Isaac; Howard, Susan; Landsea, Chris; Liu, Kam-biu; Malmquist, David; McKay, Megan; Michaels, Anthony; Nelson, Norm; O Brien, James; Scott, David; Webb, Thompson, III

266

Comparative analyses of vertebrate posterior HoxD clusters reveal atypical cluster architecture in the caecilian Typhlonectes natans  

Microsoft Academic Search

BACKGROUND: The posterior genes of the HoxD cluster play a crucial role in the patterning of the tetrapod limb. This region is under the control of a global, long-range enhancer that is present in all vertebrates. Variation in limb types, as is the case in amphibians, can probably not only be attributed to variation in Hox genes, but is likely

An Mannaert; Chris T Amemiya; Franky Bossuyt

2010-01-01

267

Subjective Probabilities Inferred from Estimates and Bets.  

National Technical Information Service (NTIS)

The similarity among veridical event probabilities, subjective probabilities inferred from Ss' estimates of the event probabilities, and subjective probabilities inferred from choices among bets involving the same events was examined. In one condition, su...

L. R. Beach L. D. Phillips

1966-01-01

268

Posterior decompression with instrumented fusion for thoracic myelopathy caused by ossification of the posterior longitudinal ligament  

Microsoft Academic Search

We evaluated the clinical results of posterior decompression with instrumented fusion (PDF) for thoracic myelopathy due to\\u000a ossification of the posterior longitudinal ligament (OPLL). A total of 24 patients underwent PDF, and their surgical outcomes\\u000a were evaluated by the Japanese Orthopaedic Association (JOA) scores (0–11 points) and by recovery rates calculated at 3, 6,\\u000a 9 and 12 months after surgery and

Masashi Yamazaki; Akihiko Okawa; Takayuki Fujiyoshi; Takeo Furuya; Masao Koda

2010-01-01

269

Clinical syndromes associated with posterior atrophy  

PubMed Central

Objective: Posterior cortical atrophy (PCA) and logopenic progressive aphasia (LPA) are clinical syndromes associated with posterior brain atrophy. We compared PCA and LPA to each other and to an age-matched group of patients with early age at onset of Alzheimer disease (EO-AD). We hypothesized that these 3 syndromes are part of a single clinical and biologic continuum. Methods: Voxel-based morphometry (VBM) was used to assess atrophy in 14 PCA, 10 LPA, and 16 EO-AD patients compared to 65 healthy controls. Genetic analysis for APOE was conducted in 30 patients and 44 controls. Four patients came to autopsy. An additional 14 were studied with the beta-amyloid specific PET with tracer 11C-labeled Pittsburgh Compound-B (PIB). Results: VBM results demonstrated that, compared to controls, each patient group showed a large area of overlapping atrophy in bilateral parietal, occipital, precuneus, posterior cingulate, posterior temporal, and hippocampal regions. Surrounding this common area, group-specific atrophy was found in small, symptom-specific regions for each group: the right ventral-occipital and superior parietal regions in PCA, the left middle and superior temporal gyri in LPA, and the prefrontal cortex in EO-AD. APOE ?4 frequency was higher in all patient groups compared to controls. Four PCA, 5 LPA, and 8 EO-AD patients showed evidence of cortical amyloid at pathology (n = 3) or on PIB-PET (n = 14). Conclusions: Logopenic progressive aphasia and posterior cortical atrophy showed largely overlapping anatomic and biologic features with early age at onset of Alzheimer disease, suggesting that these clinical syndromes represent the spectrum of clinical manifestation of the nontypical form of Alzheimer disease that presents at an early age. GLOSSARY AD = Alzheimer disease; CBD = corticobasal degeneration; EO-AD = early age at onset of Alzheimer disease; LPA = logopenic progressive aphasia; MAC = Memory and Aging Center; PCA = posterior cortical atrophy; PIB = Pittsburgh Compound-B; PPA = primary progressive aphasia; UCSF = University of California San Francisco; VBM = voxel-based morphometry.

Migliaccio, R; Agosta, F; Rascovsky, K; Karydas, A; Bonasera, S; Rabinovici, G D.; Miller, B L.; Gorno-Tempini, M L.

2009-01-01

270

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

271

Diagnostic and Prognostic Value of Clinical Findings in 83 Athletes with Posterior Thigh InjuryComparison of Clinical Findings with Magnetic Resonance Imaging Documentation of Hamstring Muscle Strain  

Microsoft Academic Search

Background: Little is known about the clinical features of posterior thigh injuries and their contribution to accurate diagnosis and prognostic assessment of hamstring muscle strain injury.Hypotheses: The clinical features of posterior thigh injury can be used to diagnose hamstring muscle strain and to predict duration of absence from competition.Study Design: Prospective clinical study.Methods: For two playing seasons, the clinical features

Geoffrey M. Verrall; John P. Slavotinek; Peter G. Barnes; Gerald T. Fon

2003-01-01

272

Giant nodular posterior scleritis simulating choroidal melanoma.  

PubMed

A 45-year-old woman, complaining of sudden visual loss in the right eye (best-corrected visual acuity: 17/200), was suspected of having a malignant melanoma of the choroid. Fundus examination revealed a massive pale-colored subretinal mass temporal to the fovea, with adjoining choroidal folds and exudative retinal detachment. Ultrasonography was suggestive of posterior scleritis. Systemic evaluation was unremarkable. The patient was treated with high-dose systemic corticosteroids. The mass lesion resolved completely, with visual recovery to 20/20. Posterior scleritis should be suspected when evaluating subretinal mass-lesions, even when large and without overt inflammation. Early treatment may improve the visual prognosis and avoid misdirected management, including enucleation. PMID:16770031

Shukla, Dhananjay; Kim, Ramasamy

2006-06-01

273

Shining a light on posterior cortical atrophy.  

PubMed

Posterior cortical atrophy (PCA) is a clinicoradiologic syndrome characterized by progressive decline in visual processing skills, relatively intact memory and language in the early stages, and atrophy of posterior brain regions. Misdiagnosis of PCA is common, owing not only to its relative rarity and unusual and variable presentation, but also because patients frequently first seek the opinion of an ophthalmologist, who may note normal eye examinations by their usual tests but may not appreciate cortical brain dysfunction. Seeking to raise awareness of the disease, stimulate research, and promote collaboration, a multidisciplinary group of PCA research clinicians formed an international working party, which had its first face-to-face meeting on July 13, 2012 in Vancouver, Canada, prior to the Alzheimer's Association International Conference. PMID:23274153

Crutch, Sebastian J; Schott, Jonathan M; Rabinovici, Gil D; Boeve, Bradley F; Cappa, Stefano F; Dickerson, Bradford C; Dubois, Bruno; Graff-Radford, Neill R; Krolak-Salmon, Pierre; Lehmann, Manja; Mendez, Mario F; Pijnenburg, Yolande; Ryan, Natalie S; Scheltens, Philip; Shakespeare, Tim; Tang-Wai, David F; van der Flier, Wiesje M; Bain, Lisa; Carrillo, Maria C; Fox, Nick C

2012-12-28

274

Tendoscopy of the posterior tibial tendon.  

PubMed

Posteromedial ankle complaints are most often caused by a disorder of the posterior tibial tendon. Two predominant groups of patients can be distinguished: the first involves younger patients who have some form of systemic inflammatory disease; the second involves older patients whose dysfunction is caused by chronic overuse. This article illustrates endoscopy of the posterior tibial tendon in a group of patients who had diverse pathology. None of the patients showed postoperative complications. All showed a quick recovery, early mobilization, none or mild postoperative pain, and nice wound healing. Although not all patients were free of complaints, all were satisfied with the intervention itself. Tendoscopy of the poterior tibial tendon offers the advantage of less morbidity, reduction of the postoperative pain, early mobilization, no wound healing problems and outpatient treatment. PMID:16798520

Bulstra, Gythe H; Olsthoorn, Paul G M; Niek van Dijk, C

2006-06-01

275

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

2007-07-06

276

Petrosal approaches to posterior circulation aneurysms.  

PubMed

Complex posterior circulation aneurysms are formidable lesions with an abysmal natural history. Their management continues to present a challenge to both endovascular and open microsurgical approaches. Affording an expansive, combined supra- and infratentorial exposure, the petrosal approaches are well suited for these challenging lesions when located along the basilar trunk or at a low-lying basilar apex. This report evaluates the evolution and application of petrosal approaches to these lesions. Excluding transsigmoid, infratentorial, or labyrinth-sacrificing approaches, the authors found 23 reports with 61 posterior circulation aneurysms treated via a petrosal approach. Although early morbidity was not negligible, rates of aneurysm occlusion (95% overall) and long-term outcome were quite laudable in light of the challenge posed by these lesions. Moreover, with accumulating experience with petrosal approaches, rates of complications are likely to wane, as neurosurgeons capitalize on the expansive exposure afforded by these indispensable approaches. PMID:22853840

Gross, Bradley A; Tavanaiepour, Daryoush; Du, Rose; Al-Mefty, Ossama; Dunn, Ian F

2012-08-01

277

Posterior midline cervical fetal cystic hygroma.  

PubMed

Posterior midline cervical cystic hygromas (PMC) are frequently found associated with chromosomal aberrations and usually do not survive. The present report illustrates diagnosis of this condition by sonography in an 18 weeks old fetus and an amniocentesis revealed 45 x0 karyotype and increased concentration of alpha-fetoproteins. Pregnancy was terminated in view of Turner's syndrome. The etiology and natural history of the condition is reviewed. PMID:1432842

Oak, S N; Redkar, R G; Kapur, V K

278

Air embolism during posterior spinal fusion  

Microsoft Academic Search

A 12-year-old healthy girl underwent a 13-level posterior spinal fusion with Harrington rod, Luque instrumentation and Drummond\\u000a spinous process wires for scoliosis repair. Her anaesthetic induction and initial intraoperative course were completely uneventful\\u000a until a precipitous blood pressure drop occurred accompanied by a significant decrease in heart rate. The Harrington rod was\\u000a being manipulated at the same time as bone

Alan S. Frankel; Robert S. Holzman

1988-01-01

279

Reversible posterior leukoencephalopathy syndrome and trastuzumab  

Microsoft Academic Search

Summary  Reversible posterior leukoencephalopathy syndrome (RPLS) is a serious condition that manifests as headache, convulsions, visual\\u000a disturbance, and a characteristic magnetic resonance image (MRI) of the brain. We now describe a case of RPLS that was likely\\u000a attributable to trastuzumab, a monoclonal antibody against human epidermal growth factor receptor-2 (HER2). Accumulating evidence\\u000a has shown that molecular targeted agents, especially those with

Hiroyasu Kaneda; Isamu Okamoto; Taroh Satoh; Kazuhiko Nakagawa

280

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

281

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

282

[Epidural hydatid cyst of the posterior fossa].  

PubMed

We report a case of epidural hydatid cyst in the posterior fossa in a 5-year-old child. The disease was revealed by raised intracranial pressure with torticollis. The diagnosis was based on the brain CT scan and MRI, and confirmed surgically. The course was uneventful. Cranial epidural hydatid cysts are very rare: only 18 cases have been reported previously in the literature. PMID:11015677

Gazzaz, M; Bouyaakoub, F A; Akhaddar, A; Derraz, S; Elkhamlichi, A

2000-09-01

283

Secondary posterior sagittal anorectoplasty for anorectal malformations  

Microsoft Academic Search

Sixteen patients who had undergone secondary posterior sagittal anorectoplasty (PSARP) for fecal incontinence were clinically followed for 3 to 10 years (mean 5.8). In addition to preoperative manometric evaluation, postoperative anorectal manometry was performed on all patients 1–3 times. Fourteen of the 16 patients underwent postoperative biofeedback training. At the last follow-up visit, the mean age of the patients was

R. J. Rintala; H. Lindahl

1995-01-01

284

Posterior scleritis as an intraocular tumour.  

PubMed

Posterior scleritis rarely presents as a large 'intraocular tumour' and continues to be a challenge in diagnosis and management. We present the case of a 66-year-old male with no known rheumatic disease, pain, proptosis, or diplopia, but with progressively decreasing visual acuity and a large, discrete 'subretinal tumour', 15 X 17 mm basal diameter and 8.3 mm apical height. Histologically the tumour was shown to be grossly thickened and necrotic sclera. PMID:2178679

Finger, P T; Perry, H D; Packer, S; Erdey, R A; Weisman, G D; Sibony, P A

1990-02-01

285

Posterior scleritis as an intraocular tumour.  

PubMed Central

Posterior scleritis rarely presents as a large 'intraocular tumour' and continues to be a challenge in diagnosis and management. We present the case of a 66-year-old male with no known rheumatic disease, pain, proptosis, or diplopia, but with progressively decreasing visual acuity and a large, discrete 'subretinal tumour', 15 X 17 mm basal diameter and 8.3 mm apical height. Histologically the tumour was shown to be grossly thickened and necrotic sclera. Images

Finger, P T; Perry, H D; Packer, S; Erdey, R A; Weisman, G D; Sibony, P A

1990-01-01

286

Delayed Diagnosis of Infected Posterior Mediastinal Teratoma  

PubMed Central

Mediastinal teratomas are rarely reported in children. We report a 12-year-old child, diagnosed and treated as empyema thoracis in a peripheral setting for 18 months. In our centre, CT scan performed revealed a well circumscribed multiloculated cystic lesion containing fat, bone and teeth, suggestive of a teratoma. The mass was excised and found to be an infected posterior mediastinal teratoma, confirmed on histopathology.

Murthy, G Rajashekhar; KS, Sanjay

2013-01-01

287

Posterior pharyngeal fat grafting for velopharyngeal insufficiency.  

PubMed

Objective : To determine if autologous fat grafting to the posterior pharynx can reduce hypernasality in patients with cleft palate and mild velopharyngeal insufficiency (VPI). Design : Retrospective case series. Setting : Tertiary care center. Patients : Eleven patients with cleft palate status after palatoplasty (with or without secondary speech surgery) with nasendoscopic evidence of VPI. Interventions : Autologous fat was harvested and injected into the posterior pharynx under general anesthesia. Main Outcome Measures : Pre- and postoperative subjective, nasometry, and nasendoscopy data. Apnea-hypopnea indices (AHIs) were also assessed. Comparisons were made using Fisher's exact test, Student's t tests, and relative risk (RR) assessments. Results : An average of 13.1 mL of fat was injected (range: 5 to 22 mL). Mean follow-up was 17.5 months (range: 12 to 25 months). Statistically significant improvements in speech resonance were identified in nasometry (Zoo passage; p ?=? .027) and subjective hypernasality assessment (p ?=? .035). Eight of the patients (73%) demonstrated normal speech resonance after posterior pharyngeal fat grafting (PPFG) on subjective or objective assessment (p ?=? .001). All five patients with previous secondary speech surgeries demonstrated normal speech resonance on similar assessment (RR ?=? 1.8; p ?=? .13). Complete velopharyngeal closure was observed in seven patients on postoperative nasendoscopy. No changes in AHIs were observed (p ?=? .581). Conclusion : PPFG may be best used as an adjunct to secondary speech surgery. In this series, PPFG was not accompanied by the negative sequelae of hyponasality, sleep apnea, or airway compromise. PMID:22329568

Lau, Darryl; Oppenheimer, Adam J; Buchman, Steve R; Berger, Mary; Kasten, Steven J

2012-02-14

288

Endovascular Management of Posterior Cerebral Artery Aneurysms  

PubMed Central

Summary The purposes of this study were to evaluate the efficacy and safety of the endovascular management of posterior cerebral artery aneurysms and compare the efficacy and safety of selective aneurysmal coiling and parent artery occlusion. We reviewed all cases with cerebral aneurysms and attention was paid to the patients with posterior cerebral artery aneurysms. Among 550 aneurysms, eight aneurysms in eight patients were located on the posterior cerebral artery, three of which presented with SAH, whereas five presented with different degrees of headache. Seven were located at the P2 segment and one at the P3 segment. One was a giant serpentine aneurysm, two were giant sac aneur-ysms, two were large and three were small. All aneurysms were successfully treated, five with selective aneurysmal coiling and three with parent artery occlusion. Two patients presenting with headache with giant aneurysms had suffered an aggravated headache for two weeks which then resolved. Others had an uneventful recovery. All patients were followed from 12 months to 56 months. Four selective aneurysmal coiling aneurysms received digital subtraction angiography, two of which needed another treatment and one was treated with parent artery occlusion, one of which recanalized slightly and one of which had further thrombosis. No rebleeding or any other symptom occurred. Whether selective aneurysmal coiling or parent artery occlusion was performed, endovascular management of PCA aneurysms was a safe and effective method. Under some conditions, parent artery occlusion was better than selective aneurysmal coiling.

Zhao, Z.-W.; Deng, J.-P.; Gao, L.; Gao, G.-D.

2008-01-01

289

Postoperative pericardial effusion and posterior pericardiotomy: related?  

PubMed

Large pericardial effusions develop in 30% of patients after cardiac surgery, and reach their maximum size after 10 days, with tamponade in 1%. The aim of this prospective randomized case-controlled study was to assess the effectiveness of a posterior pericardiotomy in preventing early and late (>30 days) development of pericardial effusion. Between April 2005 and May 2006, 410 patients with a mean age of 68.4 +/- 9.2 years undergoing coronary artery bypass grafting alone or combined with valve surgery were divided into 2 groups of 205 each. In the pericardiotomy group, a 4-cm longitudinal incision was made parallel and posterior to the phrenic nerve. Echocardiography was performed at discharge and 15 and 30 days after the operation. At 15 and 30 days postoperatively, 90.2% and 97% of patients in the pericardiotomy group were free of effusion; while none in the control group were free of effusion. A posterior pericardiotomy is easy to perform and seems to be a safe and effective means of preventing postoperative effusion and its adverse consequences. PMID:19917788

Bakhshandeh, Ali Reza; Salehi, Mehrdad; Radmehr, Hasan; Sattarzadeh, Roya; Nasr, Ahmad Reza; Sadeghpour, Amir Hossein

2009-10-01

290

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

291

Probability and Statistics K-6  

NSDL National Science Digital Library

This webpage based on the Western Canadian Protocol for grades K-6 details activities for the seventeen objectives in the Probability and Statistics strand. Each objective links to a page that includes a problem, a manipulative activity, and a game. Some of the activities require special cards, spinners, cutouts, etc. which are provided at the bottom of the webpage in PDF format.

Loewen, Craig

1998-01-01

292

The Probability of Being Decisive  

Microsoft Academic Search

The probability of a voter being decisive (PD), that is, of one vote affecting the outcome of an election, has generally been incorrectly calculated for the last twenty or more years. The method normally used is due to Banzhaf (1968) and generalised by Beck (1974). It assumes that voters know in advance how many people will vote for each candidate,

A. J. Fischer

1999-01-01

293

GPS: Geometry, Probability, and Statistics  

ERIC Educational Resources Information Center

|It might be said that for most occupations there is now less of a need for mathematics than there was say fifty years ago. But, the author argues, geometry, probability, and statistics constitute essential knowledge for everyone. Maybe not the geometry of Euclid, but certainly geometrical ways of thinking that might enable us to describe the…

Field, Mike

2012-01-01

294

Adjusted Probability Naive Bayesian Induction  

Microsoft Academic Search

. Naive Bayesian classifiers utilise a simple mathematical modelfor induction. While it is known that the assumptions on which thismodel is based are frequently violated, the predictive accuracy obtainedin discriminate classification tasks is surprisingly competitive in comparisonto more complex induction techniques. Adjusted probability naiveBayesian induction adds a simple extension to the naive Bayesian classifier.A numeric weight is inferred for each

Geoffrey I. Webb; Michael J. Pazzani

1998-01-01

295

Probability Theory and Statistical Inference  

Microsoft Academic Search

This major new textbook from a distinguished econometrician is intended for students taking introductory courses in probability theory and statistical inference. No prior knowledge other than a basic familiarity with descriptive statistics is assumed. The primary objective of this book is to establish the framework for the empirical modelling of observational (non-experimental) data. This framework known as 'Probabilistic Reduction' is

Aris Spanos

296

Probability and statistics: A reminder  

NASA Astrophysics Data System (ADS)

The main purpose of these lectures is to provide the reader with the tools needed to data analysis in the framework of physics experiments. Basic concepts are introduced together with examples of application in experimental physics. The lecture is divided into two parts: probability and statistics. It is build on the introduction from "data analysis in experimental sciences" given in [1

Clément, Benoit

2013-07-01

297

Probability interpretations of intraclass reliabilities.  

PubMed

Research where many organizations are rated by different samples of individuals such as clients, patients, or employees frequently uses reliabilities computed from intraclass correlations. Consumers of statistical information, such as patients and policy makers, may not have sufficient background for deciding which levels of reliability are acceptable. It is shown that the reliability is related to various probabilities that may be easier to understand, for example, the proportion of organizations that will be classed significantly above (or below) the mean and the probability that an organization is classed correctly given that it is classed significantly above (or below) the mean. One can view these probabilities as the amount of information of the classification and the correctness of the classification. These probabilities have an inverse relationship: given a reliability, one can 'buy' correctness at the cost of informativeness and conversely. This article discusses how this can be used to make judgments about the required level of reliabilities. Copyright © 2013 John Wiley & Sons, Ltd. PMID:23703932

Ellis, Jules L

2013-05-23

298

Conditional Independence in Applied Probability.  

ERIC Educational Resources Information Center

|This material assumes the user has the background provided by a good undergraduate course in applied probability. It is felt that introductory courses in calculus, linear algebra, and perhaps some differential equations should provide the requisite experience and proficiency with mathematical concepts, notation, and argument. The document is…

Pfeiffer, Paul E.

299

Distortions of the posterior surface in optical coherence tomography images of the isolated crystalline lens: effect of the lens index gradient  

PubMed Central

We quantify the posterior surface distortions in optical coherence tomography (OCT) images of isolated crystalline lenses. The posterior radius of curvature and asphericity obtained from OCT images acquired with the beam incident first on the anterior, and then the posterior, surface were compared. The results were compared with predictions of a ray-tracing model which includes the index gradient. The results show that the error in the radius of curvature is within the measurement reproducibility and that it can be corrected by assuming a uniform refractive index. However, accurate asphericity values require a correction algorithm that takes into account the gradient.

Borja, David; Siedlecki, Damian; de Castro, Alberto; Uhlhorn, Stephen; Ortiz, Sergio; Arrieta, Esdras; Parel, Jean-Marie; Marcos, Susana; Manns, Fabrice

2010-01-01

300

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

301

Contribution of the Posterior Compartment to the Urinary Continence Mechanism  

Microsoft Academic Search

Objective: To describe the contribution of the posterior pelvic compartment to the urethral closure mechanism.Methods: Urethral profilometry at rest and during stress was performed in 32 continent women before and after inserting a weighted (1 kg) posterior speculum to displace the posterior vaginal wall and levator ani muscles away from the bladder neck and the urethra.Results: Insertion of the speculum

Franjo Zivkovic; Karl Tamussino; Josef Haas

1998-01-01

302

Performance of an athlete with straight posterior knee instability  

Microsoft Academic Search

Isolated posterior ligamentous insufficiency of the knee frequently terminates an athlete's career and may even adversely affect the performance of tasks of daily living. Return to competitive athletics following surgical reconstruction for posterior instability is un usual. The pathophysiology of the lesion and a bio mechanical analysis are discussed. A case report of an athlete with a ruptured posterior cruciate

Thomas E. Cain; Greg H. Schwab

1981-01-01

303

Rat posterior parietal cortex: topography of corticocortical and thalamic connections  

Microsoft Academic Search

Anatomical and functional findings support the contention that there is a distinct posterior parietal cortical area (PPC) in the rat, situated between the rostrally adjacent hindlimb sensorimotor area and the caudally adjacent secondary visual areas. The PPC is distinguished from these areas by receiving thalamic afferents from the lateral dorsal (LD), lateral posterior (LP), and posterior (Po) nuclei, in the

R. L. Reep; H. C. Chandler; V. King; J. V. Corwin

1994-01-01

304

Posterior Fontanelle Sonography: An Acoustic Window into the Neonatal Brain  

Microsoft Academic Search

BACKGROUND AND PURPOSE: Sonographic brain studies are classically performed through the anterior fontanelle, but visualization of posterior supratentorial and infratentorial structures is poor with this approach. Posterior fontanelle sonography is recommended for better assessment of these structures. Our purpose was 1) to determine whether sonography of the brain through the posterior fontanelle (PF) improves visualization of brain lesions when added

Flavia Correa; Goya Enriquez; Javier Lucaya; Joaquim Piqueras; Celestino Aso; Elida Vazquez; Arantxa Ortega; Alfredo Gallart

305

Getting It Right: Joint Distribution Tests of Posterior Simulators  

Microsoft Academic Search

Analytical or coding errors in posterior simulators can produce reason- able but incorrect approximations of posterior moments. This article de- velops simple tests of posterior simulators that detect both kinds of errors, and uses them to detect and correct errors in two previously published papers. The tests exploit the fact that a Bayesian model specifies the joint distribution of observables

John Geweke

2004-01-01

306

Use of Scheimpflug corneal anterior-posterior imaging in ray-tracing intraocular lens power calculation.  

PubMed

Purpose:? To examine improvement with the use of Scheimpflug imaging of the anterior and posterior corneal surfaces in the accuracy of ray-tracing intraocular lens (IOL) power calculation for normal cataractous eyes. Methods:? Prospective case series comprised 136 eyes of 136 consecutive patients who had undergone cataract surgeries. Scheimpflug imaging of the cornea was included with routine preoperative examinations. Postoperative refractions were predicted using three methodologies; ray-tracing calculation using Scheimpflug imaging and Placido topography, ray-tracing calculations using Placido topography, and the SRK/T formula using autokeratometry. Prediction errors from the manifest refraction at 1?month postoperatively were compared between the methods. Influence of the posterior corneal curvature was also evaluated. Results:? Mean prediction errors were 0.008, -0.103 and -0.042 D, respectively without significant difference between the three methods (p?=?0.23). The prediction errors were significantly correlated with the posterior corneal curvature when the Scheimpflug imaging was not used (p?accurate as the other calculations in normal cases, showing no bias in the posterior corneal curvature, as is the case with the other calculations. PMID:23890181

Miyata, Kazunori; Otani, Shinichiro; Honbou, Naoto; Minami, Keiichiro

2013-07-26

307

Learning Resources: Statistics: Non-Probability Sampling  

NSDL National Science Digital Library

This is website, presented by Statistics Canada, examines the concept of non-probability sampling. It discusses types of non-probability sampling, differences between probability and non-probability sampling, and provides examples of non-probability sampling. Links to other topics related to sampling methods, bias, and exercise activities are also provided.

Legge, Joe A.

2008-12-11

308

Welcome to Probability by Surprise  

NSDL National Science Digital Library

Several applets that demonstrate concepts of probability using graphics and animations are presented on this Web site. Rather than getting into the details of specific theories, the applets avoid heavy number crunching and instead expose the user to example situations that generalize probabilistic concepts. This can be beneficial by letting the user see the effects of certain principles and infer how they will hold in other situations. One of the most basic applets is the Say Red Applet, which demonstrates how repeatedly choosing one of two equally likely outcomes will result in breaking even on the number of right and wrong guesses. Other applets, such as the one dealing with conditional probabilities, are more elaborate. The only criticism of this site is its lack of instructions for using the applets; however, most are quite self explanatory.

309

Impact of MCNP unresolved resonance probability-table treatment on uranium and plutonium benchmarks  

SciTech Connect

Versions of MCNP up through and including 4B have not accurately modeled neutron self-shielding effects in the unresolved resonance energy region. Recently, a probability-table treatment has been incorporated into a developmental version of MCNP. This paper presents MCNP results for a variety of uranium and plutonium critical benchmarks, calculated with and without the probability-table treatment.

Mosteller, R.D.; Little, R.C.

1998-12-31

310

What Clinicians Can Offer: Assessing and Communicating Probabilities for Individual Patient Decision Making  

Microsoft Academic Search

Accurate diagnostic and prognostic probabilities are important for physicians and their patients because of their impact on decisions. For individual patient decision making, physicians have to rely on their own judgement. Research has shown that physicians’ probability assessments are often not of high quality and that a variety of factors have a detrimental influence on their judgements. Using a formula

Danielle R. M. Timmermans

1999-01-01

311

Probable adult polyglucosan body disease.  

PubMed

Adult polyglucosan body disease is a clinicopathologic entity characterized by progressive upper and lower motor neuron dysfunction, sensory loss in the lower extremities, sphincter dysfunction, and occasionally dementia. Pathologically, numerous large polyglucosan bodies are noted in peripheral nerves, cerebral hemispheres, and the spinal cord, as well as in other systemic tissues. We present a case of probable adult polyglucosan body disease based on clinical history and examination, magnetic resonance images, and sural nerve biopsy findings. PMID:11126844

Klein, C M; Bosch, E P; Dyck, P J

2000-12-01

312

Capture probabilities for secondary resonances  

NASA Astrophysics Data System (ADS)

The tidal evolutions of Miranda and Umbriel in the 1:3, i-squaredM resonance are presently addressed via analyses of the role of secondary resonances during tidal evolution within a j:j+2 orbit-orbit resonance. The results thus obtained allow both analytical and numerical refinement of Malhotra's (1990) results for the probability of capture into secondary resonances. Attention is given to Miranda's evolution in the case of capture into the 3/1 secondary resonance.

Henrard, Jacques; Moons, Michele

1992-02-01

313

Probable Acenocoumarol-Amoxycillin Interaction  

Microsoft Academic Search

We present the case of a woman undergoing treatment with acenocoumarol for deep vein thrombosis, who maintained an international normalized ratio (INR) of between 2.5 and 4 for 2 months. Seven days after the introduction of amoxycillin (500 mg\\/8 h) for a probable respiratory infection, the patient developed spontaneous bruising, with an INR of 7.1. Treatment with amoxycillin was discontinued,

J. Soto; J. A. Sacristan; M. J. Alsar; C. Fernandez-Viadero; R. Verduga

1993-01-01

314

Advances in Regionalising Flood Probabilities  

Microsoft Academic Search

\\u000a Flood regionalisation methods are used to estimate floods of a given excedance probability, such as the 100-year flood, in\\u000a ungauged catchments, i.e. catchments, where no local streamflow data are available. They can also be used to improve flood\\u000a estimates from local data in gauged catchments. The main idea of flood regionalisation methods is to transfer flood information\\u000a from hydrologically similar

Ralf Merz

315

Probability to Achieve TSC Goal  

Microsoft Academic Search

We propose a probabilistic measure for self-checking (SC) circuits that is analogous to reliability of fault-tolerant systems. This measure is defined as the probability to achieve totally self-checking (TSC) goal at the lth cycle: TSCG(t). TSCG provides insight to the worst case dynamic behavior of SC circuits with respect to the application environment and component failure rates. TSCG surpasses the

Jien-chung Lo; Eiji Fujiwara

1996-01-01

316

[Importance of an intact posterior capsule for the vitreous body. Complication of posterior capsulotomy].  

PubMed

The various extracapsular cataract surgery techniques keep the anatomy and physiology of the eye largely untouched, since both the intact posterior capsule and the crystalline lens form a diaphragm between the aqueous humour and the vitreous. If the posterior capsule opacifies--which occurs in up to 50% within five years postoperatively--a capsulotomy becomes necessary. This increases the rate of retinal detachment and cystoid macular edema. To date no pharmacologic or immunologic means exist to prevent posterior capsule opacification. Implanting the IOL into the capsule bag and the biconvex lens design by itself reduce the incidence of opacification. The biconvex optic of the IOL seals the gap in the capsule, if a capsulotomy has been performed; fluorophotometry shows us that the diaphragm function remains intact after in the bag implantation as compared to sulcus fixated IOL. PMID:7823517

Ohrloff, C

1994-10-01

317

Empirical and Computational Tsunami Probability  

NASA Astrophysics Data System (ADS)

A key component in assessing the hazard posed by tsunamis is quantification of tsunami likelihood or probability. To determine tsunami probability, one needs to know the distribution of tsunami sizes and the distribution of inter-event times. Both empirical and computational methods can be used to determine these distributions. Empirical methods rely on an extensive tsunami catalog and hence, the historical data must be carefully analyzed to determine whether the catalog is complete for a given runup or wave height range. Where site-specific historical records are sparse, spatial binning techniques can be used to perform a regional, empirical analysis. Global and site-specific tsunami catalogs suggest that tsunami sizes are distributed according to a truncated or tapered power law and inter-event times are distributed according to an exponential distribution modified to account for clustering of events in time. Computational methods closely follow Probabilistic Seismic Hazard Analysis (PSHA), where size and inter-event distributions are determined for tsunami sources, rather than tsunamis themselves as with empirical analysis. In comparison to PSHA, a critical difference in the computational approach to tsunami probabilities is the need to account for far-field sources. The three basic steps in computational analysis are (1) determination of parameter space for all potential sources (earthquakes, landslides, etc.), including size and inter-event distributions; (2) calculation of wave heights or runup at coastal locations, typically performed using numerical propagation models; and (3) aggregation of probabilities from all sources and incorporation of uncertainty. It is convenient to classify two different types of uncertainty: epistemic (or knowledge-based) and aleatory (or natural variability). Correspondingly, different methods have been traditionally used to incorporate uncertainty during aggregation, including logic trees and direct integration. Critical sources of epistemic uncertainty in the computational analysis are the overall rate of occurrence and the inter-event distribution for landslide sources. From both empirical and computational analyses, tsunami probability as a function of runup (i.e., the tsunami hazard curve) in seismically active ocean basins such as the Pacific can be described by a modified power-law, which is similar to size distributions for other natural hazards (earthquakes, landslides, etc.). At present, it is unclear whether this form of the tsunami hazard curve is of the same form in ocean basins that have a much lower rate of tsunami occurrence (e.g, the Atlantic).

Geist, E. L.; Parsons, T.; ten Brink, U. S.; Lee, H. J.

2008-12-01

318

47 CFR 1.1623 - Probability calculation.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 2009-10-01 false Probability calculation. 1.1623 Section... General Procedures § 1.1623 Probability calculation. (a) All calculations...less than three significant digits. Probabilities will be truncated to the number...

2009-10-01

319

47 CFR 1.1623 - Probability calculation.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Probability calculation. 1.1623 Section... General Procedures § 1.1623 Probability calculation. (a) All calculations...less than three significant digits. Probabilities will be truncated to the number...

2010-10-01

320

Numbers, Please! The Telephone Directory and Probability.  

ERIC Educational Resources Information Center

|Presents a Monte Carlo simulation on probability using a telephone directory as a pseudorandom-number generator. Claims that Monte Carlo simulations offer a way to teach probability concretely and with understanding and that students enjoy the probability experiments. (ASK)|

Brunner, Regina Baron

1997-01-01

321

Pathology of the posterior tibial tendon in posterior tibial tendon insufficiency.  

PubMed

Gross and histologic examinations of 15 normal cadaver and 15 surgical posterior tibial tendons from patients with posterior tibial tendon insufficiency were performed. All surgical specimens were abnormal with enlargement distal to the medial malleolus and a dull white appearance. At histologic examination, 12 of 15 cadaver tendons displayed normal tendon structure characterized by linear orientation of collagen bundles, normal fibroblast cellularity, low vascular density, and insertional chondroid metaplasia. The surgical specimens displayed a degenerative tendinosis characterized by increased mucin content, fibroblast hypercellularity, chondroid metaplasia, and neovascularization. This resulted in marked disruption of the linear orientation of the collagen bundles. PMID:9728698

Mosier, S M; Lucas, D R; Pomeroy, G; Manoli, A

1998-08-01

322

Cervical ossification of the posterior longitudinal ligament: Anterior versus posterior approach  

PubMed Central

Background: The optimal approach to provide satisfactory decompression and minimize complications for ossification of the posterior longitudinal ligament (OPLL) involving multiple levels (3 levels or more) remains controversial. The purpose of this study was to compare the results of two surgical approaches for cervical OPLL involving multiple levels; anterior direct decompression and fixation, and posterior indirect decompression and fixation. We present a retrospective review of 56 cases followed at a single Institution. Materials and Methods: We compared patients of multiple levels cervical OPLL that were treated at a single institution either with anterior direct decompression and fixation or with posterior indirect decompression and fixation. The clinical records of the patients with a minimum duration of follow-up of 2 years were reviewed. The associated complications were recorded. Results: Fifty-six patients constitute the clinical material. 26 cases were treated by anterior corpectomy and fixation and 30 cases received posterior laminectomy and fixation. The two populations were similar. It was found that both anterior and posterior decompression and fixation can achieve satisfactory outcomes, and posterior surgery was accomplished in a shorter period of time with lesser blood loss. Although patients had comparable preoperative Japanese Orthopaedics Association (JOA) scores, those with a canal occupancy by OPLL more than 50% and managed anteriorly had better outcomes. However, for those with more severe stenosis, anterior approach was more difficult and associated with higher risks and complications. Despite its limitations in patients with high occupancy OPLLs, through the multiple level laminectomy, posterior fixation can achieve effective decompression, maintaining or restoring stability of the cervical spine, and thereby improving neural outcome and preventing the progression of OPLL. Conclusions: The posterior indirect decompression and fixation has now been adopted as the primary treatment for cervical OPLL involving multiple levels with the canal occupancy by OPLL <50% at our institution because this approach leads to significantly less implant failures. Those patients with the occupancy ?50% managed with anterior approach surgeries had better outcomes, but approach was more difficult and associated with higher risk and complications.

Lin, Dasheng; Ding, Zhenqi; Lian, Kejian; Hong, Jiayuan; Zhai, Wenliang

2012-01-01

323

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

324

Recurrent posterior reversible encephalopathy syndrome (PRES).  

PubMed

Posterior reversible encephalopathy syndrome is a proposed cliniconeuroradiological entity characterized by headache, altered mental status, cortical blindness, seizures, and other focal neurological signs, and a diagnostic magnetic resonance imaging picture. A variety of different etiologies have been reported like hypertension, pre-eclampsia/eclampsia, cyclosporin A or tacrolimus neurotoxicity, uraemia and porphyria. With early diagnosis and prompt treatment, the syndrome is usually fully reversible. We report a case of recurrent PRES of unknown aetiology following intensive care unit treatment and only moderately elevated blood pressure. Clinicians as well as radiologists must be familiar with this clinically frightening, underdiagnosed condition to assure timely diagnosis and treatment to prevent persistent deficits. PMID:15037879

Hagemann, G; Ugur, T; Witte, O W; Fitzek, C

2004-04-01

325

Posterior chamber intraocular lens dislocations and malpositions.  

PubMed

Decentration and malposition of posterior chamber intraocular lenses (PC IOL) accounts for one of the remaining and unresolved conditions associated with the implantation of these lenses. This condition assumes importance since in approximately 50% of cases where a PC IOL is removed there is an aspect of improper positioning. The common types of malpositions are: pupil capture; sunset syndrome; sunrise syndrome; horizontal decentration; and the windshield wiper syndrome. This paper will explore the causes and management of these conditions and discuss the virtues of capsular bag implantation. PMID:2679812

Obstbaum, S A; To, K

1989-08-01

326

A short history of posterior dynamic stabilization.  

PubMed

Interspinous spacers were developed to treat local deformities such as degenerative spondylolisthesis. To treat patients with chronic instability, posterior pedicle fixation and rod-based dynamic stabilization systems were developed as alternatives to fusion surgeries. Dynamic stabilization is the future of spinal surgery, and in the near future, we will be able to see the development of new devices and surgical techniques to stabilize the spine. It is important to follow the development of these technologies and to gain experience using them. In this paper, we review the literature and discuss the dynamic systems, both past and present, used in the market to treat lumbar degeneration. PMID:23326674

Gomleksiz, Cengiz; Sasani, Mehdi; Oktenoglu, Tunc; Ozer, Ali Fahir

2012-12-26

327

A Short History of Posterior Dynamic Stabilization  

PubMed Central

Interspinous spacers were developed to treat local deformities such as degenerative spondylolisthesis. To treat patients with chronic instability, posterior pedicle fixation and rod-based dynamic stabilization systems were developed as alternatives to fusion surgeries. Dynamic stabilization is the future of spinal surgery, and in the near future, we will be able to see the development of new devices and surgical techniques to stabilize the spine. It is important to follow the development of these technologies and to gain experience using them. In this paper, we review the literature and discuss the dynamic systems, both past and present, used in the market to treat lumbar degeneration.

Gomleksiz, Cengiz; Sasani, Mehdi; Oktenoglu, Tunc; Ozer, Ali Fahir

2012-01-01

328

Superior labrum anterior-to-posterior tear.  

PubMed

The patient was a 25-year-old male college student with a chief complaint of right shoulder pain. The patient was initially diagnosed with bicipital tendinitis by his physician and had been treated for 4 weeks by a physical therapist. However, his symptoms did not improve and he was unable to return to his preinjury activity levels, so he sought the services of another physical therapist for a second opinion. Due to concern for a labrum tear, the physical therapist referred the patient to an orthopaedic surgeon. Magnetic resonance arthrography revealed findings consistent with a superior labrum anterior-to-posterior tear. PMID:23202247

Sum, Jonathan C; Omid, Reza

2012-11-30

329

[Posterior interosseous nerve palsy due to lipoma].  

PubMed

A 45-year-old male patient presented with paralysis of slow onset in the right forearm and hand muscles. Electromyographic assessment revealed severe denervation in the muscles innerved by the posterior interosseous nerve. Magnetic resonance imaging demonstrated a tumoral mass compressing the nerve. The patient underwent surgical excision with an initial diagnosis of lipoma. Surgical exploration and a biopsy confirmed the diagnosis. Active wrist movements and digital extension were possible after three weeks and the patient resumed full strength six weeks after the operation. PMID:16905900

Eralp, Levent; Ozger, Harzem; Ozkan, Korhan

2006-01-01

330

Posterior fusion for an unstable axial fracture dislocation  

PubMed Central

Background: Management of avulsion fractures in the upper cervical spine remains the subject of debate. Currently, most experts favor nonoperative management of an isolated injury. However, these injuries can be complicated by soft-tissue trauma, which may require a different clinical approach to management. Accurate diagnosis of soft-tissue injuries depends on the choice of imaging modality and consideration of unique patient-specific factors. Case Description: A morbidly obese 34-year-old woman was involved in a low-velocity motor vehicle collision that caused a forceful extension of the cervical spine. Initial computed tomographic imaging demonstrated a displaced avulsion fracture of the C2 body and widening of the C2-C3 facet. However, subsequent imaging using magnetic resonance demonstrated more extensive injuries. Because bracing was not feasible due to cervical instability, the injury was treated with posterior C2-4 fusion and bone grafting. Conclusions: Even in low-velocity collisions and limited injury on imaging, patient-specific factors should be considered in management decisions. Magnetic resonance imaging showed significant ligamentous compromise and marked cervical instability, revealing potential damage to vulnerable neural structures. Magnetic resonance imaging should be considered in the initial approach to any patient with these injuries.

Emohare, Osa; Mendez, Alejandro

2013-01-01

331

Ossification of the posterior longitudinal ligament: a review of literature.  

PubMed

Ossification of the posterior longitudinal ligament (OPLL) is most commonly found in men, in the elderly, and in Asian patients. The disease can start with mild or no symptoms, but some patients progress slowly to develop symptoms of myelopathy. An accurate diagnosis through the use plain radiograph, computed tomography, and magnetic resonance imaging findings is very important to monitor the development of symptoms and to make decisions regarding a treatment plan. When symptoms are mild and non-progressive, conservative treatments and periodic observations are good enough, but once symptoms of myelopathy are present and neurologic symptoms are progressive, the treatment of choice is surgery to relieve spinal cord compression. Surgical management of OPLL continues to be controversial. Each surgical technique has some advantages and disadvantages, and the choice of operation should be decided carefully with various considerations. The patient's neurological condition, location and extent of pathology, cervical kyphosis, presence or absence of accompanied instability, and the individual surgeon's experience must be an important factors that should be considered before surgery. PMID:22164324

Choi, Byung-Wan; Song, Kyung-Jin; Chang, Han

2011-11-28

332

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.

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

2013-01-01

333

Precipitation Probabilities and Statistics for Alabama.  

National Technical Information Service (NTIS)

Tables of precipitation averages, extremes, and probabilities of selected precipitation amounts are presented for 30 Alabama locations. The probabilities were calculated by the incomplete gamma technique.

R. R. Getz L. M. Owsley

1979-01-01

334

A Study of Temporal Aspect of Posterior Parietal Cortex in Visual Search Using Transcranial Magnetic Stimulation  

NASA Astrophysics Data System (ADS)

It is known that the posterior parietal cortex (PPC) plays a dominant role in spatial processing during visual search. However, the temporal aspect of the PPC is unclear. In the present study, to investigate the temporal aspects of the PPC in feature search, we applied Transcranial Magnetic Stimulation (TMS) over the right PPC with the TMS stimulus onset asynchronies (SOAs) set at 100, 150, 200 and 250 ms after visual search stimulation. We found that when SOA was set at 150 ms, compared to the sham TMS condition, there was a significant elevation in response time when TMS pulses were applied. However, there was no significant difference between the TMS and sham TMS conditions for the other SOA settings. Therefore, we suggest that the spatial processing of feature search is probably processed in the posterior parietal cortex at about 150-170 ms after visual search stimuli presentation.

Ge, Sheng; Matsuoka, Akira; Ueno, Shoogo; Iramina, Keiji

335

Biomechanical study on tibialis posterior tendon transfers.  

PubMed

Two methods are used to route the tibialis posterior tendon anteriorly to achieve dorsiflexion: (1) around the medial side of the tibia, or the subcutaneous route; and (2) through the interosseous membrane, or the interosseous route. This study determined the effect of site of tendon insertion on ankle and foot motions and compared the efficacy of both routes. Eleven fresh normal cadaveric legs were used. The detached tibialis posterior tendon was transferred anteriorly through the interosseous membrane and anchored to the first cuneiform along the first metatarsal axis by a barbed staple. The specimen was mounted on a mechanical testing machine. Tension was applied to the tendon and ankle and foot motions were measured. The experimental procedure was repeated with tendon insertion along the second metatarsal axis and serially through to the fifth metatarsal axis. The entire experiment was repeated using the subcutaneous route. The interosseous route was more effective in achieving maximum dorsiflexion with minimal pronation. Shifting the insertion medially caused supination, whereas a more lateral insertion caused pronation. PMID:7554643

Goh, J C; Lee, P Y; Lee, E H; Bose, K

1995-10-01

336

Bayesian Posterior Distributions Without Markov Chains  

PubMed Central

Bayesian posterior parameter distributions are often simulated using Markov chain Monte Carlo (MCMC) methods. However, MCMC methods are not always necessary and do not help the uninitiated understand Bayesian inference. As a bridge to understanding Bayesian inference, the authors illustrate a transparent rejection sampling method. In example 1, they illustrate rejection sampling using 36 cases and 198 controls from a case-control study (1976–1983) assessing the relation between residential exposure to magnetic fields and the development of childhood cancer. Results from rejection sampling (odds ratio (OR) = 1.69, 95% posterior interval (PI): 0.57, 5.00) were similar to MCMC results (OR = 1.69, 95% PI: 0.58, 4.95) and approximations from data-augmentation priors (OR = 1.74, 95% PI: 0.60, 5.06). In example 2, the authors apply rejection sampling to a cohort study of 315 human immunodeficiency virus seroconverters (1984–1998) to assess the relation between viral load after infection and 5-year incidence of acquired immunodeficiency syndrome, adjusting for (continuous) age at seroconversion and race. In this more complex example, rejection sampling required a notably longer run time than MCMC sampling but remained feasible and again yielded similar results. The transparency of the proposed approach comes at a price of being less broadly applicable than MCMC.

Cole, Stephen R.; Chu, Haitao; Greenland, Sander; Hamra, Ghassan; Richardson, David B.

2012-01-01

337

[Minimally invasive adrenalectomy with posterior retroperitoneoscopy].  

PubMed

Authors report a total of 14 adrenalectomies performed from a posterior (lumbotomy) approach, using minimally invasive retroperitoneoscopic technique. The "UltraCision" scalpel, an ultrasound activated cutter-coagulation device has been used for operative tissue dissection. Two cases were converted. The mean operating time of the successful 12 cases were 128 minutes. No mortality and no septic complication occurred. The mean operative blood loss of the 12 procedures were less than 100 ml. The mean hospitalisation was 3-5 days, and the complete recovery needed 2-3 weeks. On the basis of our own experiences and the ones of prospective, randomized clinical studies of the literature, the retroperitoneoscopic adrenalectomy from a posterior approach is recommended for the surgical treatment of benign tumours of the suprarenal gland with a size less than 5 cm diameter. The low conversion- and complication-rate, the minimal operative blood loss, the short hospitalization and quick recovery time all are the advantages of this method. It can be performed after previous abdominal operation and in cases with morbid obesity. The technique is suitable for bilateral adrenalectomies as well. This method is not justified for the removal of malignant and/or larger than 5 cm adrenal tumours. Coagulopathies are contraindications. PMID:10817012

Balogh, A; Varga, L; Julesz, J; Lázár, G; Martin, K

2000-04-16

338

Myxopapillary ependymoma of the posterior mediastinum.  

PubMed

A left paravertebral mass discovered incidentally on routine examination in a 39-year-old woman is described. Computerized tomography studies revealed a 7 x 6 cm, well circumscribed, noncalcified soft tissue mass with lobular borders abutting the left inferior pulmonary vein and descending aorta. It was not possible to determine the exact anatomic location of the mass based on the imaging studies as both peripheral lung tumors and posterior mediastinal lesions may exhibit the imaging findings described here. At thoracotomy, the mass was seen to be well circumscribed, focally attached to the pleura but without involvement of lung parenchyma, and situated in the left posterior mediastinum. On histological examination, the lesion showed the classical features of myxopapillary ependymoma. Immunohistochemical studies confirmed this impression by demonstrating strong positivity of the tumor cells for S-100 protein, glial fibrillary acidic protein, and CD99 and negative staining with other differentiation markers. A review of the literature with a discussion of the histologic and radiologic differential diagnosis of these lesions is presented. PMID:16979521

Estrozi, Bruna; Queiroga, Eduardo; Bacchi, Carlos E; Faria Soares de Almeida, Virginia; Lucas de Carvalho, Jose; Lageman, Gerritt M; Rosado-de-Christenson, Melissa; Suster, Saul

2006-10-01

339

Radiological patterns of the posterior semicircular canal.  

PubMed

OBJECTIVES: The identification and definition of the radiological patterns of the posterior semicircular canal (PSC), with a view to obtain readily applicable conclusions. DESIGN: The parietal morphology of the PSC has been studied by multi-slice helical computed tomography (Philips Brilliance 6). We have determined the distribution of the different types of bone cover of the PSC, taking some previously notified, standardised measurements of normality as reference. RESULTS: 318 patients have been analysed (604 petrous bone) by CT and we have distinguished five different radiological patterns: type or normal, thick, thin, pneumatised and dehiscent. The first three patterns, normal, thick and thin, have in common the existence of a compact bone interposed between PSC and posterior fossa, being in the normal pattern has a thickness of between 0.9 and 2.5 mm (327 cases, 54.13 %), in the thick pattern is ?2.6 mm (99 cases, 16.39 %) and in the thin pattern is ?1.2 mm (158 cases, 26.15 %). The fourth pattern, pneumatised, is characterised by having retro labyrinthine cells between PSC and media fossa (19 cases, 3.14 %). Finally, a dehiscent pattern was observed in 2 cases (0.3 %). CONCLUSION: We describe five different radiological patterns: type or normal, thick, thin, pneumatised and dehiscent. The thin type (<0.5 mm or papyraceous type) and the dehiscent type would be subject to producing pathology, and in some cases the latter could be a consequence of the former. PMID:23783370

Cisneros, Ana Isabel; Whyte, Jaime; Martínez, Claudio; Gracia-Tello, Borja; Whyte, Ana; Obón, Jesús; Crovetto, Rafael; Crovetto, Miguel Angel

2013-06-20

340

Internal resection of posterior uveal melanomas  

PubMed Central

AIMS—To evaluate the safety and efficacy of internal resection in the treatment of malignant melanoma of the choroid.?METHODS—32 consecutive patients with histopathologically proved malignant choroidal melanomas were treated with internal resection. 29 of the 32 (90.6%) tumours were within 2 disc diameters of the optic nerve or fovea. The surgery was performed at two university centres by one of the authors. Follow up was between 1 and 85 months (mean 40.1 months).?RESULTS—Three patients developed distant metastases and died of malignant melanoma (metastatic and mortality rate 9.4%). In one case, distant metastases developed in association with an intraocular recurrence. There have been no other intraocular recurrences. The most common postoperative complication was vitreous haemorrhage, which occurred in 12 patients (37.5%); cataract occurred in eight eyes; and three patients developed retinal detachment postoperatively. Three of the operated eyes have been enucleated (9.4%); a total of four (12.5%) have lost light perception. 10 patients (31.2%) had visual acuities of 6/60 or better and 18 of 32 (56.3%) were between 6/120 and light perception.?CONCLUSION—These data suggest that the internal resection of posterior uveal melanomas is a reasonable globe saving management option. This treatment modality is particularly well suited to elevated tumours in close proximity to the optic nerve or fovea.?? Keywords: choroidal melanoma; internal resection; malignant melanoma; posterior uveal melanoma

Kertes, P.; Johnson, J.; Peyman, G.

1998-01-01

341

An Accurate Method for Measuring Activation Energy  

Microsoft Academic Search

In this letter, we present an accurate method for the measurement of activation energy. This method combined the excitation power dependent photoluminescence and temperature dependent photoluminescence together to obtain activation energy. We found with increasing temperature, there is a step transition from one emission mechanism to another. This step transition gives us an accurate measurement of activation energy. Using this

Xiang-Bai Chen; Jesse Huso; John L. Morrison; Leah Bergman

2005-01-01

342

MARKOV CHAIN MONTE CARLO POSTERIOR SAMPLING WITH THE HAMILTONIAN METHOD  

SciTech Connect

The Markov Chain Monte Carlo technique provides a means for drawing random samples from a target probability density function (pdf). MCMC allows one to assess the uncertainties in a Bayesian analysis described by a numerically calculated posterior distribution. This paper describes the Hamiltonian MCMC technique in which a momentum variable is introduced for each parameter of the target pdf. In analogy to a physical system, a Hamiltonian H is defined as a kinetic energy involving the momenta plus a potential energy {var_phi}, where {var_phi} is minus the logarithm of the target pdf. Hamiltonian dynamics allows one to move along trajectories of constant H, taking large jumps in the parameter space with relatively few evaluations of {var_phi} and its gradient. The Hamiltonian algorithm alternates between picking a new momentum vector and following such trajectories. The efficiency of the Hamiltonian method for multidimensional isotropic Gaussian pdfs is shown to remain constant at around 7% for up to several hundred dimensions. The Hamiltonian method handles correlations among the variables much better than the standard Metropolis algorithm. A new test, based on the gradient of {var_phi}, is proposed to measure the convergence of the MCMC sequence.

K. HANSON

2001-02-01

343

Multisegmental cervical ossification of the posterior longitudinal ligament: Anterior vs posterior approach  

Microsoft Academic Search

Aims: To determine the surgical approach in patients with multisegmental (four or more segments) OPLL of the cervi- cal spine. Methods and Materials: Data of 27 patients who had undergone either an anterior (corpectomy with excision of OPLL and interbody fusion=14 patients) or posterior ap- proach (laminectomy=12, laminoplasty=1 patient) for the multisegmental cervical OPLL was analyzed retrospectively. The patients in

VijendraK Jain; SubodhK Jain; PravinS Salunke; KH Vyas; SanjayS Behari; Deepu Banerji

2005-01-01

344

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

345

Prehension movements in a patient (AC) with posterior parietal cortex damage and posterior callosal section  

Microsoft Academic Search

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 prehension was

Victor Frak; Yves Paulignan; Marc Jeannerod; François Michel; Henri Cohen

2006-01-01

346

Accurate modeling of optical multiplexer\\/demultiplexer concatenation in transparent multiwavelength optical networks  

Microsoft Academic Search

This paper presents an accurate theoretical model for the study of concatenation of optical multiplexers\\/demultiplexers (MUXs\\/DMUXs) in transparent multiwavelength optical networks. The model is based on a semianalytical technique for the evaluation of the error probability of the network topology. The error-probability evaluation takes into account arbitrary pulse shapes, arbitrary optical MUX\\/DMUX, and electronic low-pass filter transfer functions, and non-Gaussian

I. Roudas; N. Antoniades; T. Otani; T. E. Stern; R. E. Wagner; D. Q. Chowdhury

2002-01-01

347

MSPI False Indication Probability Simulations  

SciTech Connect

This paper examines false indication probabilities in the context of the Mitigating System Performance Index (MSPI), in order to investigate the pros and cons of different approaches to resolving two coupled issues: (1) sensitivity to the prior distribution used in calculating the Bayesian-corrected unreliability contribution to the MSPI, and (2) whether (in a particular plant configuration) to model the fuel oil transfer pump (FOTP) as a separate component, or integrally to its emergency diesel generator (EDG). False indication probabilities were calculated for the following situations: (1) all component reliability parameters at their baseline values, so that the true indication is green, meaning that an indication of white or above would be false positive; (2) one or more components degraded to the extent that the true indication would be (mid) white, and “false” would be green (negative) or yellow (negative) or red (negative). In key respects, this was the approach taken in NUREG-1753. The prior distributions examined were the constrained noninformative (CNI) prior used currently by the MSPI, a mixture of conjugate priors, the Jeffreys noninformative prior, a nonconjugate log(istic)-normal prior, and the minimally informative prior investigated in (Kelly et al., 2010). The mid-white performance state was set at ?CDF = ?10 ? 10-6/yr. For each simulated time history, a check is made of whether the calculated ?CDF is above or below 10-6/yr. If the parameters were at their baseline values, and ?CDF > 10-6/yr, this is counted as a false positive. Conversely, if one or all of the parameters are set to values corresponding to ?CDF > 10-6/yr but that time history’s ?CDF < 10-6/yr, this is counted as a false negative indication. The false indication (positive or negative) probability is then estimated as the number of false positive or negative counts divided by the number of time histories (100,000). Results are presented for a set of base case parameter values, and three sensitivity cases in which the number of FOTP demands was reduced, along with the Birnbaum importance of the FOTP.

Dana Kelly; Kurt Vedros; Robert Youngblood

2011-03-01

348

Delayed neutron emission probability measurements  

NASA Astrophysics Data System (ADS)

Some neutrons are emitted from fission fragments several seconds to several minutes after fission occurs. These delayed neutrons play a key role for the conduct and in safety aspects of nuclear reactors [1]. But the probabilities to emit such neutrons (Pn) are not well known. A summary of different database and compilation of Pn values is presented to show these discrepancies and uncertainties. Experiments are carried out at the Lohengrin mass spectrometer (at Institut Laue Langevin in Grenoble) and at the ISOLDE facility (CERN) in order to measure some Pn values. Two different techniques are used: either by using gamma-rays detection or neutron emission detection. These two techniques and some preliminary results are presented.

Mathieu, L.; Serot, O.; Materna, T.; Bail, A.; Köster, U.; Faust, H.; Litaize, O.; Dupont, E.; Letourneau, A.; Panebianco, S.; Kratz, K. L.

2009-10-01

349

Evaluation and management of posterior ankle pain in dancers.  

PubMed

Posterior ankle pain is a common complaint in dancers. There are multiple structures in the posterior ankle that have the potential to be the source of pain. The objective of this article is to review several of the most common causes of posterior ankle pain: peroneal tendon subluxation, posterior impingement syndrome secondary to a painful os trigonum, posterior talus osteochondritis dissecans, flexor hallucis longus tendinopathy, and posterior tibial tendinopathy. For dancers, we offer typical clinical presentations of these disorders to increase awareness and provide guidance regarding when to seek professional medical attention. For medical personnel who are responsible for optimizing dancers' health and training, we include a discussion of pertinent physical exam findings, diagnostic imaging options, non-operative and operative management, as well as surgical suggestions and postoperative rehabilitation guidelines. PMID:23759482

Luk, Pamela; Thordarson, David; Charlton, Timothy

2013-01-01

350

Posterior chamber pseudophakes in glaucoma patients.  

PubMed

In the past, glaucoma has been considered a relative contraindication to the use of an intraocular lens (IOL) in a patient undergoing cataract extraction. In this study, we examined postoperative intraocular pressure (IOP) control for three months postoperatively in 46 eyes with glaucoma undergoing cataract extraction with implantation of a posterior chamber IOL. Twenty-six eyes or 56.5% could be classified as having improved IOP control three months postoperatively. At the same time, 19 eyes or 41.3% demonstrated the same IOP control after lens implantation. Thus, 45 of the total of 46 eyes had as good or better postoperative IOP control. Of the 46 eyes, 100% required preoperative glaucoma medication, while postoperatively only 41% required medication. PMID:3960473

McMahan, L B; Monica, M L; Zimmerman, T J

1986-03-01

351

Posterior reduction and stabilization of painful spondylolisthesis.  

PubMed

The authors reported 16 cases of first to third grade painful spondylolisthesis. The treatment was posterior reduction and stabilization in one stage operation by modified Vidal et al and Luque techniques. The operation consisted of stabilization of an above involved vertebra and another one below with a rectangular rod and sublaminar wirings. The pedicular screws were inserted through the Harrington hooks which levered upon the rectangular rod for reduction of the displaced vertebra. The posterolateral intertransverse arthrodesis of two spinal segments was also added. A 2-5-year follow-up study showed all patients were relieved from pain initially, and could ambulate early following the operation. The vertebral displacement did not increase postoperatively and solid posterolateral fusion was obtained. PMID:1306189

Arthornthurasook, A; Prabhawong, P

1992-10-01

352

Stage IV posterior tibial tendon rupture.  

PubMed

Adult acquired flatfoot deformity progresses through well defined stages as set out by Johnson and Strom. Myerson modified this classification system with the addition of a fourth, more advanced stage of the disease. This stage describes the involvement of the tibiotalar joint in addition to the hindfoot malalignment seen in stages II and III. This most advanced stage is comprised of a hindfoot valgus deformity, resulting from degeneration of the posterior tibial tendon, with associated valgus tilting of the talus within the mortise. The deformity at the tibiotalar joint may or may not be rigid. Although rigid deformities are still best treated with fusions of the ankle and hindfoot, supple tibiotalar deformity may be treated with joint sparing procedures involving reconstructive procedures of the foot and deltoid ligaments. PMID:17561206

Bluman, Eric M; Myerson, Mark S

2007-06-01

353

Cerebellar mutism after posterior cranial fossa surgery.  

PubMed

Mutism is a rare sequel of PCF tumor removal. Three patients aged 5 to 20 years old with mutism after posterior fossa surgery are presented. Suboccipital craniectomy was performed in all patients with grossly total removal of a medulloblastoma. The mutism that may occur after an operation for a PCF lesion has been explained in functional and/or organic terms. To date, 24 similar cases of mutism following cerebellar operations have been reported in the literature. We review the features of the syndrome in the light of the published cases and speculate on the underlying physiopathology. The absence of long tract or other brain stem signs, together with a presence of dysarthria during the recovery of speech, suggested a organic cerebellar cause of the mutism. PMID:8913962

Salvati, M; Cervoni, L; Santoro, A

1996-03-01

354

Iodothyronine 5-deiodinase in rat posterior pituitary.  

PubMed

We first describe the presence of iodothyronine 5-deiodinase (5D) in the neural lobe of rat pituitary. 6-n-Propyl-2-thiouracil (PTU), a specific inhibitor of type-I deiodinase, had no effect, showing that 5D in neurohypophysis is of type-III isozyme, which is specific for 5-deiodination and has been found only in the brain, placenta and skin. The presence of 5D (type-III) together with our previous report of 5'-deiodinase (type-I in euthyroidism and type-II in hypothyroidism) shows that the isozymes of deiodinases in the neurohypophysis are quite similar to those in the brain. These data suggest a previously unrecognized role of thyroid hormone in posterior pituitary physiology. PMID:1417847

Tanaka, K; Shimatsu, A; Imura, H

1992-10-15

355

Anterior dislocation after a posterior stabilized total knee arthroplasty.  

PubMed

Dislocation of a total knee arthroplasty is a rare but serious complication. In previous literature, when dislocation does occur, it is usually in the posterior direction in cases with a posterior stabilized total knee arthroplasty due to cam jump. We report an unusual case of anterior dislocation of an 11-year-old posterior stabilized total knee arthroplasty in a 55-year-old woman with rheumatoid arthritis occurred after a slip. PMID:21641178

Lee, Su Chan; Jung, Kwang Am; Nam, Chang Hyun; Hwang, Seung Hyun; Lee, Won Jun; Park, Il Seok

2012-02-01

356

Dysfunction of the posterior cruciate ligament in total knee arthroplasty  

Microsoft Academic Search

Purpose  Total knee arthroplasty (TKA) is typically carried out either with retention (CR) of the posterior cruciate ligament (PCL)\\u000a or with sacrifice of this ligament and implantation of a posterior stabilised (PS) prosthesis. This paper investigates a comparison\\u000a of PCL function in knees treated for osteoarthritis with TKA where the PCL is preserved to those knees treated with TKA and\\u000a posterior

James Edmund Arbuthnot; Olwyn Wainwright; Gareth Stables; Manickam Rathinam; David I. Rowley; Michael J. McNicholas

2011-01-01

357

Thalamocortical projections to the posterior parietal cortex in the monkey  

Microsoft Academic Search

Thalamo-cortical projections to the posterior parietal cortex (PPC) were investigated electrophysiologically in the monkey. Cortical field potentials evoked by the thalamic stimulation were recorded with electrodes chronically implanted on the cortical surface and at a 2.0–3.0 mm cortical depth in the PPC. The stimulation of the nucleus lateralis posterior (LP), nucleus ventralis posterior lateralis pars caudalis (VPLc), and nucleus pulvinaris

Ryuichi Matsuzaki; Shin-ichi Kyuhou; Kazuko Matsuura-Nakao; Hisae Gemba

2004-01-01

358

Posterior Thigh Muscle Injuries in Elite Track and Field Athletes  

Microsoft Academic Search

Introduction: Posterior thigh muscle injuries in athletes are common, and prediction of recovery time would be of value.Hypothesis: Knee active range of motion deficit 48 hours after a unilateral posterior thigh muscle injury correlates with time to full recovery.Study Design: Cohort study (prognosis); Level of evidence, 2.Methods: One hundred sixty-five track and field athletes with acute, first-time, unilateral posterior thigh

Nikolaos Malliaropoulos; Emmanuel Papacostas; Olga Kiritsi; Agapi Papalada; Nikolaos Gougoulias; Nicola Maffulli

2010-01-01

359

Basic Monte Carlo Methods for Estimating Posterior Quantities  

Microsoft Academic Search

\\u000a The fundamental goal of Bayesian computation is to compute posterior quantities of interest. When the posterior distribution\\u000a ?(¸|D) is high dimensional, one is typically driven to do multidimensional integration to evaluate marginal posterior summaries\\u000a of the parameters. When a Bayesian model is complicated, analytical or exact numerical evaluation may fail to solve this computational\\u000a problem. In this regard, the Monte

Ming-Hui Chen; Qi-Man Shao; Joseph G. Ibrahim

360

Posterior Circulation Stroke: Animal Models and Mechanism of Disease  

PubMed Central

Posterior circulation stroke refers to the vascular occlusion or bleeding, arising from the vertebrobasilar vasculature of the brain. Clinical studies show that individuals who experience posterior circulation stroke will develop significant brain injury, neurologic dysfunction, or death. Yet the therapeutic needs of this patient subpopulation remain largely unknown. Thus understanding the causative factors and the pathogenesis of brain damage is important, if posterior circulation stroke is to be prevented or treated. Appropriate animal models are necessary to achieve this understanding. This paper critically integrates the neurovascular and pathophysiological features gleaned from posterior circulation stroke animal models into clinical correlations.

Lekic, Tim; Ani, Chizobam

2012-01-01

361

Missing posterior teeth and risk of temporomandibular disorders.  

PubMed

There is disagreement about the association between missing posterior teeth and the presence of temporomandibular disorders (TMD). Here, the purpose was to investigate whether the number of missing posterior teeth, their distribution, age, and gender are associated with TMD. Seven hundred and forty-one individuals, aged 21-60 years, with missing posterior teeth, 386 with and 355 without TMD, were included. Four variables-gender, age, the number of missing posterior teeth, and the number of dental quadrants with missing posterior teeth-were analyzed with a logistic regression model. All four variables-gender (OR = 1.59, men = 1, women = 2), age (OR = 0.98), the number of missing posterior teeth (OR = 0.51), and the number of dental quadrants with missing posterior teeth (OR = 7.71)-were entered into the logistic model (P < 0.01). The results indicate that individuals who lose posterior teeth, with fewer missing posterior teeth but in more quadrants, have a higher prevalence of TMD, especially young women. PMID:19783804

Wang, M Q; Xue, F; He, J J; Chen, J H; Chen, C S; Raustia, A

2009-10-01

362

Application-dependent Probability Distributions for Offshore Wind Speeds  

NASA Astrophysics Data System (ADS)

The higher wind speeds of the offshore environment make it an attractive setting for future wind farms. With sparser field measurements, the theoretical probability distribution of short-term wind speeds becomes more important in estimating values such as average power output and fatigue load. While previous studies typically compare the accuracy of probability distributions using R2, we show that validation based on this metric is not consistent with validation based on engineering parameters of interest, namely turbine power output and extreme wind speed. Thus, in order to make the most accurate estimates possible, the probability distribution that an engineer picks to characterize wind speeds should depend on the design parameter of interest. We introduce the Kappa and Wakeby probability distribution functions to wind speed modeling, and show that these two distributions, along with the Biweibull distribution, fit wind speed samples better than the more widely accepted Weibull and Rayleigh distributions based on R2. Additionally, out of the 14 probability distributions we examine, the Kappa and Wakeby give the most accurate and least biased estimates of turbine power output. The fact that the 2-parameter Lognormal distribution estimates extreme wind speeds (i.e. fits the upper tail of wind speed distributions) with least error indicates that not one single distribution performs satisfactorily for all applications. Our use of a large dataset composed of 178 buoys (totaling ~72 million 10-minute wind speed observations) makes these findings highly significant, both in terms of large sample size and broad geographical distribution across various wind regimes. Boxplots of R2 from the fit of each of the 14 distributions to the 178 boy wind speed samples. Distributions are ranked from left to right by ascending median R2, with the Biweibull having the closest median to 1.

Morgan, E. C.; Lackner, M.; Vogel, R. M.; Baise, L. G.

2010-12-01

363

Psychophysics of the probability weighting function  

NASA Astrophysics Data System (ADS)

A probability weighting function w(p) for an objective probability p in decision under risk plays a pivotal role in Kahneman–Tversky prospect theory. Although recent studies in econophysics and neuroeconomics widely utilized probability weighting functions, psychophysical foundations of the probability weighting functions have been unknown. Notably, a behavioral economist Prelec (1998) [4] axiomatically derived the probability weighting function w(p)=exp(?() (0probability weighting function from psychophysical laws of perceived waiting time in probabilistic choices. Also, the relations between the parameters in the probability weighting function and the probability discounting function in behavioral psychology are derived. Future directions in the application of the psychophysical theory of the probability weighting function in econophysics and neuroeconomics are discussed.

Takahashi, Taiki

2011-03-01

364

Deep Posterior Compartment Strength and Foot Kinematics in Subjects With Stage II Posterior Tibial Tendon Dysfunction  

PubMed Central

Background Tibialis posterior muscle weakness has been documented in subjects with Stage II posterior tibial tendon dysfunction (PTTD) but the effect of weakness on foot structure remains unclear. The association between strength and flatfoot kinematics may guide treatment such as the use of strengthening programs targeting the tibialis posterior muscle. Materials and Methods Thirty Stage II PTTD subjects (age; 58.1 ± 10.5 years, BMI 30.6 ± 5.4) and 15 matched controls (age; 56.5 ± 7.7 years, BMI 30.6 ± 3.6) volunteered for this study. Deep Posterior Compartment strength was measured from both legs of each subject and the strength ratio was used to compare each subject’s involved side to their uninvolved side. A 20% deficit was defined, a priori, to define two groups of subjects with PTTD. The strength ratio for each group averaged; 1.06 ± 0.1 (range 0.87 to 1.36) for controls, 1.06 ± 0.1 (range, 0.89 to 1.25), for the PTTD strong group, and 0.64 ± 0.2 (range 0.42 to 0.76) for the PTTD weak group. Across four phases of stance, kinematic measures of flatfoot were compared between the three groups using a two-way mixed effect ANOVA model repeated for each kinematic variable. Results Subjects with PTTD regardless of group demonstrated significantly greater hindfoot eversion compared to controls. Subjects with PTTD who were weak demonstrated greater hindfoot eversion compared to subjects with PTTD who were strong. For forefoot abduction and MLA angles the differences between groups depended on the phase of stance with significant differences between each group observed at the pre-swing phase of stance. Conclusion Strength was associated with the degree of flatfoot deformity observed during walking, however, flatfoot deformity may also occur without strength deficits.

Neville, Christopher; Flemister, Adolph S.; Houck, Jeff R.

2010-01-01

365

Probable linezolid-induced pancytopenia  

PubMed Central

A 75-year-old male outpatient with cardiac disease, diabetes, chronic renal insufficiency and iron deficiency anemia was prescribed linezolid 600 mg twice daily for a methicillin-resistant Staphylococcus aureus diabetic foot osteomyelitis. After one week, his blood counts were consistent with baseline values. The patient failed to return for subsequent blood work. On day 26, he was admitted to hospital with acute renal failure secondary to dehydration, and was found to be pancytopenic (erythrocytes 2.5x1012/L, leukocytes 2.9x109/L, platelets 59x109/L, hemoglobin 71 g/L). The patient was transfused, and linezolid was discontinued. His blood counts improved over the week and remained at baseline two months later. The patient's decline in blood counts from baseline levels met previously established criteria for clinical significance. Application of the Naranjo scale indicated a probable relationship between pancytopenia and linezolid. Clinicians should be aware of this rare effect with linezolid, and prospectively identify patients at risk and emphasize weekly hematological monitoring.

Lakhani, Nita; Thompson, William; Bombassaro, Anne Marie

2005-01-01

366

Posterior mediastinal mass: Do we need to worry much?  

PubMed

Anesthetic management of mediastinal masses is challenging. There is abundant literature available on anesthesia management of anterior mediastinal mass. Anesthetic management of posterior mediastinal mass lesions normally have uneventful course. We describe airway collapse and difficult mechanical ventilation in the postoperative period in a patient with posterior mediastinal mass. PMID:24107699

Lalwani, Parin; Chawla, Rajiv; Kumar, Mritunjay; Tomar, Akhilesh S; Raman, Padmalatha

367

Medioventral part of the posterior thalamus in the mouse  

Microsoft Academic Search

The posterior thalamus (Po) consists of heterogeneous groups of cells, which have not been clearly defined. In the present study, we focused on a part of the Po in the mouse brain, which is located caudally to the ventral posterior nucleus and rostromedially to the medial geniculate nucleus and shows distinct calretinin immunoreactivity. While we found the region had a

Keisuke Motomura; Toshio Kosaka

2011-01-01

368

Mini-Incision Posterior Approach for Hip Arthroplasty  

Microsoft Academic Search

Objective To reduce the trauma to soft tissues through a shortened incision for a posterior approach for hip replacement. Indications Patients requiring primary hip replacement or revision. Contraindications Open wounds in area of incision. Planned femoral osteotomy. Surgical Technique Incision of 10-15 cm, splitting of the gluteus maximus, and division of the piriformis insertion allow exposure of the posterior capsule

D. Kevin Lester; Melvin Helm

2001-01-01

369

Underlying principles of visual shape selectivity in posterior inferotemporal cortex  

Microsoft Academic Search

Object perception depends on shape processing in the ventral visual pathway, which in monkeys culminates in inferotemporal cortex (IT). Here we provide a description of fundamental quantitative principles governing neural selectivity for complex shape in IT. By measuring responses to large, parametric sets of two-dimensional (2D) silhouette shapes, we found that neurons in posterior IT (Brodmann's areas TEO and posterior

Scott L Brincat; Charles E Connor

2004-01-01

370

Posterior fontanelle cranial ultrasound: anatomic and sonographic correlation  

Microsoft Academic Search

Objective: The purpose of this study was to correlate normal brain anatomy as seen on posterior fontanelle cranial sonography with anatomical sections of the premature infant brain. Materials and methods: Images obtained from 93 cranial ultrasound examinations performed via both the anterior and posterior fontanelle in 53 infants, ranging in gestational age from 24 to 42 weeks, were reviewed to

Nigel G. Anderson; Robyn Hay; Margaret Hutchings; Martin Whitehead; Brian Darlow

1995-01-01

371

Posterior Fracture-Dislocation ofthe Hip in Sports  

Microsoft Academic Search

Posterior fracture-dislocation of the hip is a rare injury in sports and is most frequently seen after road traffic accidents. A posterior fracture-dislocation of the hip that occurred in an adult sportsman during rugby is reported. This case illustrates the great forces that can be sustained by the hip joint of rugby players. Operative stabilization led to a stable hip

Peter V. Giannoudis; Boris A. Zelle; Raman P. Kamath; Hans C. Pape

2003-01-01

372

Selective Posterior Rhizotomy: Evolution of Theory and Practice  

Microsoft Academic Search

The spastic type of cerebral palsy has become more prevalent due to improved survival rates of premature infants. Selective posterior rhizotomy is a neurosurgical procedure which is designed to reduce spasticity and has been successfully used for children with spastic cerebral palsy. Although the procedure of posterior rhizotomy is nearly 100 years old, a revised technique was introduced in 1981.

Warwick J. Peacock; Loretta A. Staudt

1992-01-01

373

Posterior dislocation of the shoulder: recommendations for a classification  

Microsoft Academic Search

Posterior dislocation of the should is rare, constituting only 2.1% of all shoulder dislocations. The mechanisms of injury may be due to direct or indirect forces, and constitutional predisposing factors also play a role. Anatomically, 97.5% of dislocations are subacromial. Three hundred articles published in the international literature concerning posterior shoulder dislocation and subluxation were reviewed and a classification determined

K.-D. Heller; J. Forst; R. Forst; B. Cohen

1994-01-01

374

Management of Hydrocephalus Complicating Childhood Posterior Fossa Tumors  

Microsoft Academic Search

We examined the treatment of hydrocephalus in children with posterior fossa tumors to (1) compare the use of external ventricular drainage (EVD) with ventriculoperitoneal shunts (VPS), (2) determine the frequency of postoperative hydrocephalus requiring permanent shunts, and (3) determine which factors predict the need for a permanent shunt. The records of 58 children with posterior fossa tumors and associated hydrocephalus

Mark S. Diets; Leland Albright

1989-01-01

375

Numerical approximations of marginals from “well - behaved” joint posteriors  

Microsoft Academic Search

In applications of Bayesian statistics to econometric models involving several parameters, one often obtains joint posterior densities that cannot be integrated analytically. This paper suggests a method to approximate the marginal densities of individual parameters, when the non analytically integrable joint posteriors are, “well-behaved”. The approach consists in making appropriate changes of variables such that specific conditional densities become very

Marcel G. Dagenais; Tran Cong Liem

1981-01-01

376

Conditional probability modulates visual search efficiency.  

PubMed

We investigated the effects of probability on visual search. Previous work has shown that people can utilize spatial and sequential probability information to improve target detection. We hypothesized that performance improvements from probability information would extend to the efficiency of visual search. Our task was a simple visual search in which the target was always present among a field of distractors, and could take one of two colors. The absolute probability of the target being either color was 0.5; however, the conditional probability-the likelihood of a particular color given a particular combination of two cues-varied from 0.1 to 0.9. We found that participants searched more efficiently for high conditional probability targets and less efficiently for low conditional probability targets, but only when they were explicitly informed of the probability relationship between cues and target color. PMID:24146645

Cort, Bryan; Anderson, Britt

2013-10-17

377

An Introduction to Normal Probability Paper.  

National Technical Information Service (NTIS)

The report contains an introduction to normal probability paper and it provides the following: Brief review of the normal curve; procedure for constructing normal probability paper; the procedure for plotting on the paper when the expected value for order...

J. F. Santner

1973-01-01

378

The Probability Distribution for a Biased Spinner  

ERIC Educational Resources Information Center

|This article advocates biased spinners as an engaging context for statistics students. Calculating the probability of a biased spinner landing on a particular side makes valuable connections between probability and other areas of mathematics. (Contains 2 figures and 1 table.)|

Foster, Colin

2012-01-01

379

Conditional probability modulates visual search efficiency  

PubMed Central

We investigated the effects of probability on visual search. Previous work has shown that people can utilize spatial and sequential probability information to improve target detection. We hypothesized that performance improvements from probability information would extend to the efficiency of visual search. Our task was a simple visual search in which the target was always present among a field of distractors, and could take one of two colors. The absolute probability of the target being either color was 0.5; however, the conditional probability—the likelihood of a particular color given a particular combination of two cues—varied from 0.1 to 0.9. We found that participants searched more efficiently for high conditional probability targets and less efficiently for low conditional probability targets, but only when they were explicitly informed of the probability relationship between cues and target color.

Cort, Bryan; Anderson, Britt

2013-01-01

380

Estimating exceedance probabilities of extreme floods.  

National Technical Information Service (NTIS)

Estimates of the exceedance probabilities of extreme floods are needed for risk analysis of dams and nuclear facilities. A new approach using a joint probability distribution of extreme rainfalls and antecedent soil moisture conditions, along with a rainf...

T. A. Fontaine K. W. Potter

1994-01-01

381

On a paradox of probability theory  

NASA Astrophysics Data System (ADS)

Costa de Beauregard's proposal concerning retrocausality is formulated in terms of conditional probabilities. In its current formulation his proposal reveals a paradox intrinsic to elementary probability theory. The paradox is perhaps related to the nonlocal causality revealed through Bell's theorem.

Stuart, C. I. J. M.

1991-06-01

382

Compressive creep of posterior and anterior composite resins in water.  

PubMed

The compressive creep and the recovery of commercially available composites, 2 kinds for posterior and 2 kinds for anterior use, in water were examined. In posterior composites, creep strain after 500h at a stress level of 8.3 kgf/mm2 was significantly small (within 1%). The results of the compressive creep test showed that posterior composites would be resistant to occlusal stress. Creep strain was higher in anterior composites than that in posterior composites because of their lower inorganic filler content. The rate of recovery of composites was rapid immediately after the creep test. The water sorption of composites after 500h test was almost constant at some reduced stress levels, especially in posterior composites. PMID:7758282

Hirano, S; Hirasawa, T

1994-12-01

383

Posteriorly migrated thoracic disc herniation: a case report  

PubMed Central

Introduction Posterior epidural migration of thoracic disc herniation is extremely rare but may occur in the same manner as in the lumbar spine. Case presentation A 53-year-old Japanese man experienced sudden onset of incomplete paraplegia after lifting a heavy object. Magnetic resonance imaging revealed a posterior epidural mass compressing the spinal cord at the T9-T10 level. The patient underwent emergency surgery consisting of laminectomy at T9-T10 with right medial facetectomy, removal of the mass lesion, and posterior instrumented fusion. Histological examination of the mass lesion yielded findings consistent with sequestered disc material. His symptoms resolved, and he was able to resume walking without a cane 4 weeks after surgery. Conclusions Pre-operative diagnosis of posterior epidural migration of herniated thoracic disc based on magnetic resonance imaging alone may be overlooked, given the rarity of this pathology. However, this entity should be considered among the differential diagnoses for an enhancing posterior thoracic extradural mass.

2013-01-01

384

Representation of numerosity in posterior parietal cortex.  

PubMed

Humans and animals appear to share a similar representation of number as an analog magnitude on an internal, subjective scale. Neurological and neurophysiological data suggest that posterior parietal cortex (PPC) is a critical component of the circuits that form the basis of numerical abilities in humans. Patients with parietal lesions are impaired in their ability to access the deep meaning of numbers. Acalculiac patients with inferior parietal damage often have difficulty performing arithmetic (2 + 4?) or number bisection (what is between 3 and 5?) tasks, but are able to recite multiplication tables and read or write numerals. Functional imaging studies of neurologically intact humans performing subtraction, number comparison, and non-verbal magnitude comparison tasks show activity in areas within the intraparietal sulcus (IPS). Taken together, clinical cases and imaging studies support a critical role for parietal cortex in the mental manipulation of numerical quantities. Further, responses of single PPC neurons in non-human primates are sensitive to the numerosity of visual stimuli independent of low-level stimulus qualities. When monkeys are trained to make explicit judgments about the numerical value of such stimuli, PPC neurons encode their cardinal numerical value; without such training PPC neurons appear to encode numerical magnitude in an analog fashion. Here we suggest that the spatial and integrative properties of PPC neurons contribute to their critical role in numerical cognition. PMID:22666194

Roitman, Jamie D; Brannon, Elizabeth M; Platt, Michael L

2012-05-31

385

Posterior endoscopic discectomy: Results in 300 patients  

PubMed Central

Background: Posterior endoscopic discectomy is an established method for treatment of lumbar disc herniation. Many studies have not been reported in literature for lumbar discectomy by Destandau Endospine System. We report a series of 300 patients operated for lumbar dissectomy by Destandau Endospine system. Materials and Methods: A total of 300 patients suffering from lumbar disc herniations were operated between January 2002 and December 2008. All patients were operated as day care procedure. Technique comprised localization of symptomatic level followed by insertion of an endospine system devise through a 15 mm skin and fascial incision. Endoscopic discectomy is then carried out by conventional micro disc surgery instruments by minimal invasive route. The results were evaluated by Macnab's criteria after a minimum followup of 12 months and maximum up to 24 months. Results: Based on modified Macnab's criteria, 90% patients had excellent to good, 8% had fair, and 2% had poor results. The complications observed were discitis and dural tear in five patients each and nerve root injury in two patients. 90% patients were able to return to light and sedentary work with an average delay of 3 weeks and normal physical activities after 2 months. Conclusion: Edoscopic discectomy provides a safe and minimal access corridor for lumbar discectomy. The technique also allows early postoperative mobilization and faster return to work.

Kaushal, Mohinder; Sen, Ramesh

2012-01-01

386

A rare posterior cranial fossa tumor.  

PubMed

Among tumors of the central nervous system, tumors of the mixed glioneuronal type form an important recognized subset. Some of the examples for mixed glioneuronal tumors include gangliocytoma, dysembryoplastic neuroepithelial tumor (DNT), ganglioglioma, anaplastic ganglioglioma, and central neurocytoma. The rosette-forming glioneuronal tumor (RGNT) of the fourth ventricle is a new entity that has only slowly emerged in the literature due to its prior classification with other low-grade mixed glial and neuronal tumors. These tumors are relatively infrequent lesions, and therefore, they can be challenging to diagnose for the practicing pathologist. This is a rare biphasic tumor with clearly defined neurocytic and glial components. The tumor is found exclusively in the posterior fossa, where it arises in the midline, usually occupying a substantial fraction of the fourth ventricle, and it is observed by magnetic resonance imaging (MRI) as a circumscribed, solid mass with heterogeneous contrast enhancement. We describe here a case of RGNT occurring in a 22-year-old male. PMID:23361291

Nandeesh, Bevinahalli N; Chabra, Manmeet Singh; Babu, Manjaly K; Chand, Ashish K

387

Two Artifacts of Probability Field Simulation  

Microsoft Academic Search

Probability field simulation is being used increasingly to simulate geostatistical realizations. The method can be faster than conventional simulation algorithms and it is well suited to integrate prior soft information in the form of local probability distributions. The theoretical basis of probability field simulation has been established when there are no conditioning data; however, no such basis has been established

Michael J. Pyrcz; Clayton V. Deutsch

2001-01-01

388

Fault-Tree Analysis by Fuzzy Probability  

Microsoft Academic Search

In conventional fault-tree analysis, the failure probabilities of components of a system are treated as exact values in estimating the failure probability of the top event. For many systems, it is often difficult to evaluate the failure probabilities of components from past occurrences because the environments of the systems change. Furthermore, it might be necessary to consider possible failure of

Hideo Tanaka; L. T. Fan; F. S. Lai; K. Toguchi

1983-01-01

389

Teaching Probabilities and Statistics to Preschool Children  

ERIC Educational Resources Information Center

This study considers the teaching of probabilities and statistics to a group of preschool children using traditional classroom activities and Internet games. It was clear from this study that children can show a high level of understanding of probabilities and statistics, and demonstrate high performance in probability games. The use of Internet…

Pange, Jenny

2003-01-01

390

Collision probability for an occupancy problem  

Microsoft Academic Search

We study the collision probability for a balls-and-bins problem, developed by Wendl [Wendl, M., 2003. Collision probability between sets of random variables. Statistics & Probability Letters 64, 249–254] using the method of enumerating surjections. We give the exact distribution for the number of collisions and the expectation which has a simple expression.

Toshio Nakata

2008-01-01

391

Subjective and objective probabilities in quantum mechanics  

SciTech Connect

We discuss how the apparently objective probabilities predicted by quantum mechanics can be treated in the framework of Bayesian probability theory, in which all probabilities are subjective. Our results are in accord with earlier work by Caves, Fuchs, and Schack, but our approach and emphasis are different. We also discuss the problem of choosing a noninformative prior for a density matrix.

Srednicki, Mark [Department of Physics, University of California, Santa Barbara, California 93106 (United States)

2005-05-15

392

Teaching Probabilities and Statistics to Preschool Children  

ERIC Educational Resources Information Center

|This study considers the teaching of probabilities and statistics to a group of preschool children using traditional classroom activities and Internet games. It was clear from this study that children can show a high level of understanding of probabilities and statistics, and demonstrate high performance in probability games. The use of Internet…

Pange, Jenny

2003-01-01

393

Morphometric analysis of posterior fossa and foramen magnum  

PubMed Central

Introduction: Configuration and size of the foramen magnum and posterior fossa plays an important role in the pathophysiology of the posterior fossa and craniovertebral junction disorders. This study is aimed to find out various dimensions of the foramen magnum and posterior fossa. Materials and Methods: This is a prospective study of 100 consecutive normal computerized tomography (CT) scans of posterior fossa and 100 dry adult skulls without any bony abnormality. The posterior fossa volume was calculated by abc/2 in method 1 and by advanced work station of CT scan in method 2. Various dimensions of posterior fossa and foramen magnum were also studied. Results: Age ranged from 16 to 89 years with a mean of 51.3 years. Mean height of posterior fossa were 3.01 cm (±0.22) and 3.52 (±0.43) cm in dry skull and CT scan group, respectively (P < 0.0001). Mean volume of posterior fossa were 157.88 (±27.94) cm3 and 159.58 (±25.73) cm3 by method 1 and method 2, respectively (P > 0.05). All the dimensions of posterior fossa and foramen magnum were larger in male as compared to female. Mean anteroposterior (AP), transverse diameter and surface area of the foramen magnum were 3.31 (±0.35) cm, 2.76 (±0.31) cm, and 729.15 (±124.87) mm2, respectively, in CT scan group as compared to 3.41 (±0.29) cm, 2.75 (±0.25) cm, and 747.67 (±108.60) mm2, respectively, in dry skull group. Conclusion: Normal values of posterior fossa and foramen magnum could serve as a future reference. Dry skull dimensions could be different from CT scan measurement. More studies are needed as there could be variations in dimensions in different regions in India

Kanodia, Gautam; Parihar, Vijay; Yadav, Yad R; Bhatele, Pushp R; Sharma, Dhananjay

2012-01-01

394

Mitral Valve Mechanics Following Posterior Leaflet Patch Augmentation  

PubMed Central

Background and aim of the study Attention towards the optimization of mitral valve repair methods is increasing. Patch augmentation is one strategy used to treat functional ischemic mitral regurgitation (FIMR). The study aim was to investigate the force balance changes in specific chordae tendineae emanating from the posterior papillary muscle in a FIMR-simulated valve, following posterior leaflet patch augmentation. Methods Mitral valves were obtained from 12 pigs (body weight 80 kg). An in vitro test set-up simulating the left ventricle was used to hold the valves. The left ventricular pressure was regulated with water to simulate different static pressures during valve closure. A standardized oval pericardial patch (17 × 29 mm) was introduced into the posterior leaflet from mid P2 to the end of the P3 scallop. Dedicated miniature transducers were used to record the forces exerted on the chordae tendineae. Data were acquired before and after 12 mm posterior and 5 mm apical posterior papillary muscle displacement to simulate the effect from one of the main contributors of FIMR, before and after patch augmentation. Results The effect of displacing the posterior papillary muscle induced tethering on the intermediate chordae tendineae to the posterior leaflet, and resulted in a 39.8% force increase (p = 0.014). Posterior leaflet patch augmentation of the FIMR valve induced a 31.1% force decrease (p = 0.007). There was no difference in force between the healthy and the repaired valve simulations (p = 0.773). Conclusion Posterior leaflet patch augmentation significantly reduced the forces exerted on the intermediate chordae tendineae from the posterior papillary muscle following FIMR simulation. As changes in chordal tension lead to a redistribution of the total stress exerted on the valve, patch augmentation may have an adverse long-term influence on mitral valve function and remodeling.

Rahmani, Azadeh; Rasmussen, Ann Q.; Honge, Jesper L.; Ostli, Bjorn; Levine, Robert A.; Hagege, Albert; Nygaard, Hans; Nielsen, Sten L.; Jensen, Morten O.

2013-01-01

395

Modeling the Effect of Reward Amount on Probability Discounting  

PubMed Central

The present study with college students examined the effect of amount on the discounting of probabilistic monetary rewards. A hyperboloid function accurately described the discounting of hypothetical rewards ranging in amount from $20 to $10,000,000. The degree of discounting increased continuously with amount of probabilistic reward. This effect of amount was not due to changes in the rate parameter of the discounting function, but rather was due to increases in the exponent. These results stand in contrast to those observed with the discounting of delayed monetary rewards, in which the degree of discounting decreases with reward amount due to amount-dependent decreases in the rate parameter. Taken together, this pattern of results suggests that delay and probability discounting reflect different underlying mechanisms. That is, the fact that the exponent in the delay discounting function is independent of amount is consistent with a psychophysical scaling interpretation, whereas the finding that the exponent of the probability-discounting function is amount-dependent is inconsistent with such an interpretation. Instead, the present results are consistent with the idea that the probability-discounting function is itself the product of a value function and a weighting function. This idea was first suggested by Kahneman and Tversky (1979), although their prospect theory does not predict amount effects like those observed. The effect of amount on probability discounting was parsimoniously incorporated into our hyperboloid discounting function by assuming that the exponent was proportional to the amount raised to a power. The amount-dependent exponent of the probability-discounting function may be viewed as reflecting the effect of amount on the weighting of the probability with which the reward will be received.

Myerson, Joel; Green, Leonard; Morris, Joshua

2011-01-01

396

Accurate force measurement using optical interferometer  

NASA Astrophysics Data System (ADS)

The present status and the future prospects of a method for accurate force measurement, the levitation mass method (LMM), is reviewed. The LMM has been proposed and improved by the authors. In the LMM, the inertial force of a mass levitated using an aero-static linear bearing is used as the reference/known force applied to the objects under test, such as force transducers, materials or structures. The inertial force of the levitated mass is measured using an optical interferometer. Since the force is one of the most major physical quantities, the application of the LMM as the most accurate dynamic force measurement method is very wide.

Fujii, Yusaku

2012-06-01

397

Atomic Transition Probabilities of Aluminum. A Critical Compilation  

NASA Astrophysics Data System (ADS)

This compilation is the second in a series of updates to Atomic Transition Probabilities, Sodium through Calcium, published in 1969 by Wiese et al. [Atomic Transition Probabilities, Vol. II, Vol. II: Sodium through Calcium, NSROS-NBS Vol. 2 (U.S. GPO, Washington, D.C., 1969)]. Atomic transition probabilities have been critically evaluated and compiled for about 5000 spectral lines of aluminum (nuclear charge Z=13). The cited values and their estimated uncertainties are based on our consideration of all available theoretical and experimental literature sources. All ionization stages (except for hydrogenic) are covered, and the data are presented in separate tables for each atom and ion. Separate listings are given for ``allowed'' (electric dipole) and ``forbidden'' (magnetic dipole plus electric and magnetic quadrupole) transitions. In each spectrum, lines are grouped into multiplets which are arranged in order of ascending lower- and upper-level energies, respectively. For each line, the emission transition probability Aki, the line strength S, and (for allowed lines) the absorption oscillator strength fik are given, together with the spectroscopic designation, the wavelength, the statistical weights, and the energy levels of the lower and upper states. The estimated relative uncertainties of the line strength are also indicated, as are the source citations. We include only those lines whose transition rates are deemed sufficiently accurate to qualify as reference values. Short introductions precede the tables for each ion.

Kelleher, D. E.; Podobedova, L. I.

2008-06-01

398

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

Microsoft Academic Search

he 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

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

2001-01-01

399

Calibrating Subjective Probabilities Using Hierarchical Bayesian Models  

NASA Astrophysics Data System (ADS)

A body of psychological research has examined the correspondence between a judge's subjective probability of an event's outcome and the event's actual outcome. The research generally shows that subjective probabilities are noisy and do not match the "true" probabilities. However, subjective probabilities are still useful for forecasting purposes if they bear some relationship to true probabilities. The purpose of the current research is to exploit relationships between subjective probabilities and outcomes to create improved, model-based probabilities for forecasting. Once the model has been trained in situations where the outcome is known, it can then be used in forecasting situations where the outcome is unknown. These concepts are demonstrated using experimental psychology data, and potential applications are discussed.

Merkle, Edgar C.

400

Software Estimation: Developing an Accurate, Reliable Method.  

National Technical Information Service (NTIS)

From a management perspective, it is essential that software estimates used in a TSP launch are as accurate as possible. Significant growth due to estimation inaccuracy can wreak havoc on a team attempting to stay within cost and schedule while executing ...

B. Hodgins B. Sinclair C. Rickets

2011-01-01

401

Fluorine Compatible Apparatus for Accurate Pvt Measurements.  

National Technical Information Service (NTIS)

A fluorine compatible apparatus, incorporating numerous safety features, is described. This apparatus has been used to make accurate determinations of the PVT properties of gaseous and liquid fluorine from 53.5 K (the triple point) to 300 K and to pressur...

G. C. Straty R. Prydz

1970-01-01

402

Accurate hydrocarbon estimates attained with radioactive isotope  

Microsoft Academic Search

To make accurate economic evaluations of new discoveries, an oil company needs to know how much gas and oil a reservoir contains. The porous rocks of these reservoirs are not completely filled with gas or oil, but contain a mixture of gas, oil and water. It is extremely important to know what volume percentage of this water--called connate water--is contained

Hubbard

1983-01-01

403

Mean shift for accurate license plate localization  

Microsoft Academic Search

This paper presents a region-based algorithm for accurate license plate localization, where mean shift is utilized to filter and segment color vehicle images into candidate regions. Three features are extracted in order to decide whether a candidate region represents a real license plate, namely, rectangularity, aspect ratio, and edge density. Then, the Mahalanobis classifier is used with respect to above

Wenjing Jia; Huaifeng Zhang; Xiangjian He; M. Piccardi

2005-01-01

404

Accurate Assessment--Compelling Evidence for Practice  

ERIC Educational Resources Information Center

Childhood overweight and obesity is a public health concern not just because of its growing prevalence but also for its serious and lasting health consequences. Though height and weight measures are easy to obtain and New Hampshire Head Start sites measure height and weight of their enrollees, there are numerous challenges related to accurate

Flynn, Regina T.; Anderson, Ludmila; Martin, Nancy R.

2010-01-01

405

How Accurately can we Calculate Thermal Systems?  

Microsoft Academic Search

I would like to determine how accurately a variety of neutron transport code packages (code and cross section libraries) can calculate simple integral parameters, such as K{sub eff}, for systems that are sensitive to thermal neutron scattering. Since we will only consider theoretical systems, we cannot really determine absolute accuracy compared to any real system. Therefore rather than accuracy, it

D Cullen; R N Blomquist; C Dean; D Heinrichs; M A Kalugin; M Lee; Y Lee; R MacFarlan; Y Nagaya; A Trkov

2004-01-01

406

The Accurate Hose Model for VPN Provisioning  

Microsoft Academic Search

This work considers the problem of VPN provisioning, focusing on the process of dimensioning the links belonging to the route that connects VPN endpoints, according to the specified traffic demands. To accomplish this, we propose a new model, the Accurate Hose, which can take into consideration a complete or partial traffic matrix and supports group based bandwidth requirements, while maintaining

Dênio Mariz; Judith Kelner; Djamel Sadok; Carlos A. Kamienski

407

Accurate planar area and contour length measurement  

Microsoft Academic Search

This paper describes a technique for accurately estimating the area and contour length of a planar non-polygonal region in the scene. The approach taken is to formulate a continuous model of the boundary of the region in the scene and use the image data to estimate the parameters of the model. The required information is then extracted from the model

R. J. Valkenburg; R. Kakarala

1997-01-01

408

Accurate Assessment--Compelling Evidence for Practice  

ERIC Educational Resources Information Center

|Childhood overweight and obesity is a public health concern not just because of its growing prevalence but also for its serious and lasting health consequences. Though height and weight measures are easy to obtain and New Hampshire Head Start sites measure height and weight of their enrollees, there are numerous challenges related to accurate

Flynn, Regina T.; Anderson, Ludmila; Martin, Nancy R.

2010-01-01

409

Simple accurate expressions for planar spiral inductances  

Microsoft Academic Search

We present several new simple and accurate expressions for the DC inductance of square, hexagonal, octagonal, and circular spiral inductors. We evaluate the accuracy of our expressions, as well as several previously published inductance expressions, in two ways: by comparison with three-dimensional field solver predictions and by comparison with our own measurements, and also previously published measurements. Our simple expression

Sunderarajan S. Mohan; Maria del Mar Hershenson; Stephen P. Boyd; Thomas H. Lee

1999-01-01

410

Accurate Astrometry in the Solar System  

Microsoft Academic Search

The U.S. Naval Observatory Flagstaff Station (NOFS) has been providing highly accurate astrometry to the Solar Systems Dynamics (SSD) group at JPL since 1991, in support of numerous planetary missions and observing efforts. In 2005, NOFS began a new phase of this work by expanding the range of possible targets, investigating the magnitude variability of asteroids observed at NOFS, and

Alice K. B. Monet

2010-01-01

411

An Accurate Analog Ferrite Phase Shifter  

Microsoft Academic Search

An analog ferrite phase shifter has been developed for applications requiring an accurate relationship between phase shift and control current. A prototype unit is described that operates over a 1.3 GHz. range at X-band with VSWR under 1.2:1, loss under 1 dB., hysteresis at ±1 degree, and negligible frequency dispersion of phase shift.

C. R. Boyd

1971-01-01

412

EMISSIVITY - THE CRUX OF ACCURATE RADIOMETRIC MEASUREMENT  

Microsoft Academic Search

Infrared (IR) radiometry is a very useful form of temperature measurement. Its advantages over contact thermometry are that it has quick response times and it does not have to come in contact with the area being measured. One of its major drawbacks is that it not as accurate as contact thermometry. One of the major sources of this uncertainty is

Frank Liebmann

413

Aspheric versus Spherical Posterior Chamber Intraocular Lenses  

PubMed Central

Purpose To compare spherical aberration and contrast sensitivity function following implantation of four different foldable posterior chamber intraocular lenses (IOLs), namely Sensar, Akreos AO, Tecnis, and AcrySof IQ. Methods In this randomized clinical trial, 68 eyes of 68 patients with senile cataracts underwent phacoemulsification and IOL implantation with Sensar (n=17), Akreos AO (n=17), Tecnis (n=17), or AcrySof IQ (n=17). Uncorrected visual acuity (UCVA) and best spectacle-corrected visual acuity (BSCVA), spherical aberration and contrast sensitivity function (CSF) were compared among the study groups, 3 months after surgery. Results There was no significant difference between the study groups in terms of age (P = 0.21). Mean postoperative BSCVA with Sensar, Akreos AO, Tecnis, and AcrySof IQ was 0.15±0.10, 0.12±0.9, 0.08±0.08, and 0.08±0.07 logMAR, respectively (P=0.08). Spherical aberration measured over a 4 mm pupil was significantly higher with Sensar and Akreos AO than the two other IOLs. The difference between Tecnis and AcrySof IQ was significantly in favor of the former IOL. Over a 6 mm pupil, spherical aberrations were comparable with Sensar and Akreos AO, furthermore spherical aberration was also comparable among eyes implanted with Akreos AO, AcrySof IQ, and Tecnis. Sensar yielded significantly inferior results as compared to Acrysof IQ and Tecnis. CSF with Sensar was inferior to the three aspheric IOLs at the majority of spatial frequencies. Tecnis yielded significantly better mesopic CSF at 1.5 and 3 cycles per degree spatial frequencies. Conclusion Tecnis and AcrySof IQ provided significantly better visual function as compared to Sensar and Akreos AO, especially with smaller pupil size. However, this difference diminished with increasing pupil size.

Jafarinasab, Mohammad-Reza; Feizi, Sepehr; Baghi, Ahmad-Reza; Ziaie, Hossein; Yaseri, Mehdi

2010-01-01

414

Proximal dentatothalamocortical tract involvement in posterior fossa syndrome  

PubMed Central

Posterior fossa syndrome is characterized by cerebellar dysfunction, oromotor/oculomotor apraxia, emotional lability and mutism in patients after infratentorial injury. The underlying neuroanatomical substrates of posterior fossa syndrome are unknown, but dentatothalamocortical tracts have been implicated. We used pre- and postoperative neuroimaging to investigate proximal dentatothalamocortical tract involvement in childhood embryonal brain tumour patients who developed posterior fossa syndrome following tumour resection. Diagnostic imaging from a cohort of 26 paediatric patients previously operated on for an embryonal brain tumour (13 patients prospectively diagnosed with posterior fossa syndrome, and 13 non-affected patients) were evaluated. Preoperative magnetic resonance imaging was used to define relevant tumour features, including two potentially predictive measures. Postoperative magnetic resonance and diffusion tensor imaging were used to characterize operative injury and tract-based differences in anisotropy of water diffusion. In patients who developed posterior fossa syndrome, initial tumour resided higher in the 4th ventricle (P = 0.035). Postoperative magnetic resonance signal abnormalities within the superior cerebellar peduncles and midbrain were observed more often in patients with posterior fossa syndrome (P = 0.030 and 0.003, respectively). The fractional anisotropy of water was lower in the bilateral superior cerebellar peduncles, in the bilateral fornices, white matter region proximate to the right angular gyrus (Tailerach coordinates 35, –71, 19) and white matter region proximate to the left superior frontal gyrus (Tailerach coordinates –24, 57, 20). Our findings suggest that multiple bilateral injuries to the proximal dentatothalamocortical pathways may predispose the development of posterior fossa syndrome, that functional disruption of the white matter bundles containing efferent axons within the superior cerebellar peduncles is a critical underlying pathophysiological component of posterior fossa syndrome, and that decreased fractional anisotropy in the fornices and cerebral cortex may be related to the abnormal neurobehavioural symptoms of posterior fossa syndrome.

Phillips, Nicholas S.; Laningham, Fred H.; Patay, Zoltan; Gajjar, Amar; Wallace, Dana; Boop, Frederick; Sanford, Robert; Ness, Kirsten K.; Ogg, Robert J.

2009-01-01

415

Probability matching priors for linear calibration  

Microsoft Academic Search

Summary  In the linear calibration problem, a model is fit to paired observations arising from two measurement techniques, one known\\u000a to be far more accurate (but also more expensive) than the other. The fitted model is then used with univariate observations\\u000a from the less accurate technique to impute values from the more accurate one. The Bayesian paradigm emerges as attractive\\u000a in

M. Ghosh; B. P. Carlin; M. S. Srivastava

1995-01-01

416

Feedback about More Accurate versus Less Accurate Trials: Differential Effects on Self-Confidence and Activation  

ERIC Educational Resources Information Center

|One purpose of the present study was to examine whether self-confidence or anxiety would be differentially affected by feedback from more accurate rather than less accurate trials. The second purpose was to determine whether arousal variations (activation) would predict performance. On Day 1, participants performed a golf putting task under one…

Badami, Rokhsareh; VaezMousavi, Mohammad; Wulf, Gabriele; Namazizadeh, Mahdi

2012-01-01

417

Causes and management of posterior chamber lens displacement.  

PubMed

Posterior chamber lens implantation, although satisfactory in almost 95% of cases, can result in lens dislocation. Whereas serious dislocations such as the sunset and windshield-wiper syndromes are less frequent since the introduction of highly flexible loops, posterior vaulting of the pseudophakos may cause problems, eventually provoking a posterior capsule rupture and a secondary sunset syndrome. The iris-capture syndrome can be almost entirely prevented by using angulated loops. If it occurs, it can usually be corrected easily. Small decentrations as well as oblique malpositions of the pseudophakos are usually less important but should be recognized, analyzed, and prevented. PMID:3988619

Böke, W R; Krüger, H C

1985-03-01

418

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.

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

2012-01-01

419

Ossification of the posterior longitudinal ligament: a case report  

PubMed Central

Ossification of the posterior longitudinal ligament (OPLL) has recently been recognized as a clinical entity. It is a rare condition, having a higher incidence in the Japanese population. It is characterized by hyperplasia of cartilage cells with eventual endochondral ossification of the posterior longitudinal ligament. The radiographic signs are characteristic and consist of a linear band of ossified tissue along the posterior margin of the vertebral body. OPLL can be associated with mild to serious neurological complications due to spinal cord or nerve root compression, or it may be asymptomatic. This paper reviews the radiological, clinical and therapeutic aspects of this rare condition. ImagesFigures 1 and 2Figures 3 and 4

Aker, PD; O'Connor, SM; Mior, SA; Beauchemin, D

1989-01-01

420

Incidence and surgical importance of the posterior gastric artery.  

PubMed Central

In a series of 61 adult cadavers, the posterior gastric artery was found in 38 (62.3%), originating from the superior aspect of the mid-third of the splenic artery. The posterior gastric artery, running behind the parietal peritoneum of the omental bursa, produced a peritoneal fold before reaching the posterior wall of the superior portion of the gastric body, near the cardiac region, and the fundus. Its high incidence, hidden origin, deep course, and distribution make this artery very important for surgical procedures relating to the stomach, pancreas, spleen, and celiac region. It may be crucial, especially if partial gastric resection of splenectomy have obliterated other gastric vessels.

Suzuki, K; Prates, J C; DiDio, L J

1978-01-01

421

Gull-wing haptic design for posterior chamber intraocular lens.  

PubMed

The current trend toward implantation of posterior chamber lenses within the capsular bag rather than the ciliary sulcus seems logical in light of the increasing evidence of uveal damage from sulcus fixated posterior chamber lenses. However, long-term, successful capsular bag fixation has not been demonstrated with current popular looped lenses of either flat or angulated styles. This report evaluated a new gull-wing loop design that seems to have advantages of both planar and angulated loop styles for support of posterior chamber lenses. PMID:3305870

Masket, S

1987-07-01

422

Building the posterior lateral line system in zebrafish  

PubMed Central

The posterior lateral line in zebrafish has emerged as an excellent system to study how a sensory organ system develops. Here we review recent studies that illustrate how interactions between multiple signaling pathways coordinate cell fate, morphogenesis and collective migration of cells in the posterior lateral line primordium. These studies also illustrate how the posterior lateral line system is contributing much more broadly to our understanding of mechanisms operating during the growth, regeneration and self-organization of other organ systems during development and disease.

Chitnis, Ajay B; Nogare, Damian Dalle; Matsuda, Miho

2012-01-01

423

Avulsed posterior edge of the tibia. Earle's or Volkmann's triangle?  

PubMed

The term Volkmann's triangle for the avulsed posterior edge of the tibia in fracture-dislocations of the ankle is incorrect. Volkmann did not publish any articles relating to the posterior edge of the tibia. Credit should go to Henry Earle, who was an outstanding British surgeon of the first half of 19th century. He described avulsion of the posterior edge of the tibia in 1828. In 1823 he also published a monograph entitled Practical observations in surgery in which he described a specially designed bed for the conservative treatment of proximal fractures of the femur. PMID:15274275

Bartonícek, J

2004-07-01

424

Probability and Quantum Paradigms: the Interplay  

SciTech Connect

Since the introduction of Born's interpretation of quantum wave functions as yielding the probability density of presence, Quantum Theory and Probability have lived in a troubled symbiosis. Problems arise with this interpretation because quantum probabilities exhibit features alien to usual probabilities, namely non Boolean structure and non positive-definite phase space probability densities. This has inspired research into both elaborate formulations of Probability Theory and alternate interpretations for wave functions. Herein the latter tactic is taken and a suggested variant interpretation of wave functions based on photo detection physics proposed, and some empirical consequences are considered. Although incomplete in a few details, this variant is appealing in its reliance on well tested concepts and technology.

Kracklauer, A. F. [Bauhaus Universitaet, PF 2040, 99401 Weimar (Germany)

2007-12-03

425

Probability and Quantum Paradigms: the Interplay  

NASA Astrophysics Data System (ADS)

Since the introduction of Born's interpretation of quantum wave functions as yielding the probability density of presence, Quantum Theory and Probability have lived in a troubled symbiosis. Problems arise with this interpretation because quantum probabilities exhibit features alien to usual probabilities, namely non Boolean structure and non positive-definite phase space probability densities. This has inspired research into both elaborate formulations of Probability Theory and alternate interpretations for wave functions. Herein the latter tactic is taken and a suggested variant interpretation of wave functions based on photo detection physics proposed, and some empirical consequences are considered. Although incomplete in a few details, this variant is appealing in its reliance on well tested concepts and technology.

Kracklauer, A. F.

2007-12-01

426

Approximating model probabilities in Bayesian information criterion and decision-theoretic approaches to model selection in phylogenetics.  

PubMed

A priori selection of models for use in phylogeny estimation from molecular sequence data is increasingly important as the number and complexity of available models increases. The Bayesian information criterion (BIC) and the derivative decision-theoretic (DT) approaches rely on a conservative approximation to estimate the posterior probability of a given model. Here, we extended the DT method by using reversible jump Markov chain Monte Carlo approaches to directly estimate model probabilities for an extended candidate pool of all 406 special cases of the general time reversible + ? family. We analyzed 250 diverse data sets in order to evaluate the effectiveness of the BIC approximation for model selection under the BIC and DT approaches. Model choice under DT differed between the BIC approximation and direct estimation methods for 45% of the data sets (113/250), and differing model choice resulted in significantly different sets of trees in the posterior distributions for 26% of the data sets (64/250). The model with the lowest BIC score differed from the model with the highest posterior probability in 30% of the data sets (76/250). When the data indicate a clear model preference, the BIC approximation works well enough to result in the same model selection as with directly estimated model probabilities, but a substantial proportion of biological data sets lack this characteristic, which leads to selection of underparametrized models. PMID:20671039

Evans, Jason; Sullivan, Jack

2010-07-29

427

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

428

Accurate and robust inverse Cholesky factorization  

NASA Astrophysics Data System (ADS)

In this paper, an algorithm for an accurate matrix factorization based on Cholesky factorization for extremely ill-conditioned matrices is proposed. The Cholesky factorization is widely used for solving a system of linear equations whose coefficient matrix is symmetric and positive definite. However, it sometimes breaks down by the presence of an imaginary root due to the accumulation of rounding errors, even if the matrix is actually positive definite. To overcome this, a completely stable algorithm named inverse Cholesky factorization is investigated, which never breaks down as long as the matrix is symmetric and positive definite. The proposed algorithm consists of standard numerical algorithms and an accurate algorithm for dot products. Moreover, it is shown that the algorithm can also verify the positive definiteness of a given real symmetric matrix. Numerical results are presented for illustrating the performance of the proposed algorithms.

Ogita, Takeshi; Oishi, Shin'ichi

429

Probability of occurrence of extreme magnetic storms  

NASA Astrophysics Data System (ADS)

calculate the probability of extreme magnetic storms in the solar cycle 24, cumulative distribution functions are investigated using an 89 year list of magnetic storms recorded at Kakioka Magnetic Observatory. It is found that the probability of occurrence of extreme magnetic storms can be modeled as a function of maximum sunspot number of a solar cycle, and the probability of another Carrington storm occurring within the next decade is estimated to be 4-6%.

Kataoka, Ryuho

2013-05-01

430

A Brief Introduction to Probability and Statistics  

NSDL National Science Digital Library

This online textbook covers the following probability and statistics topics: independence, Venn diagrams, Bayes's theorem, counting, Binomial expansion, Binomial distribution, continuous distributions, infinitesimals in probability, averaging, variance, Gaussian distribution, random walks, correlation, causation, linear regression, unbiased estimators, hypothesis testing, shape of the distribution, and variance of mean differences. This is a nice reference tool for a board look at statistics and probability. While each lesson is fairly brief, it still covers a great majority in terms of the scope of this discipline.

Deutsch, Josh

2009-09-01

431

ACCURATE DSM PRODUCTION FROM UNMANNED HELICOPTER SYSTEMS  

Microsoft Academic Search

Since the previous ISPRS conference in 2004 there have been several developments in modern navigation and earth observation. One of the new developments is accurate production of dense Digital Surface Models (DSMs), three-dimensional (3D) vector maps, and high resolution orthophotos from unmanned aerial vehicles (UAVs) with a state-of-the-art navigation and control system for hands-off autonomous flights. The authors have successfully

R. B. Haarbrink; H. Eisenbeiss

432

An Accurate, Simplified Model Intrabeam Scattering  

SciTech Connect

Beginning with the general Bjorken-Mtingwa solution for intrabeam scattering (IBS) we derive an accurate, greatly simplified model of IBS, valid for high energy beams in normal storage ring lattices. In addition, we show that, under the same conditions, a modified version of Piwinski's IBS formulation (where {eta}{sub x,y}{sup 2}/{beta}{sub x,y} has been replaced by {Eta}{sub x,y}) asymptotically approaches the result of Bjorken-Mtingwa.

Bane, Karl LF

2002-05-23

433

A fast and accurate light reflection model  

Microsoft Academic Search

This multimedia paper elaborates on the comprehensive physically-based light reflection model introduced by He et al. [11.To explain the model more fully, the paper gives an overview of the light re-flection process at a surfiace, and employs an interactive graphical tool to demonstrate the reflection model's directional behavior. To make the model more practical, the paper describes an accurate ap-proximation

Xiao D. He; Patrick O. Heynen; Richard L. Phillips; Kenneth E. Torrance; David H. Salesin; Donald P. Greenberg

1992-01-01

434

An Accurate, Simplified Model Intrabeam Scattering  

Microsoft Academic Search

Beginning with the general Bjorken-Mtingwa solution for intrabeam scattering (IBS) we derive an accurate, greatly simplified model of IBS, valid for high energy beams in normal storage ring lattices. In addition, we show that, under the same conditions, a modified version of Piwinski's IBS formulation (where η{sub x,y}²\\/β{sub x,y} has been replaced by Î{sub x,y}) asymptotically approaches the result of

Karl L. F. Bane; Karl LF

2002-01-01

435

Cycle-Accurate Microarchitecture Performance Evaluation  

Microsoft Academic Search

We present the design, implementation, and eval- uation of a circuit we call the Statistics Module that captures cycle-accurate performance data at (or above) the microarchitecture layer. The circuit is de- ployed introspectively—in the architecture itself— using an FPGA in the context of a soft-core imple- mentation of a SPARC architecture (LEON). Acces- sible over the Internet, the circuit can

Richard Hough; Phillip Jones; Scott Friedman; Roger Chamberlain; Jason Fritts; John Lockwood; Ron Cytron

2006-01-01

436

Accurate overlaying for mobile augmented reality  

Microsoft Academic Search

Mobile augmented reality requires accurate alignment of virtual information with objects visible in the real world. We describe a system for mobile communications to be developed to meet these strict alignment criteria using a combination of computer vision, inertial tracking and low-latency rendering techniques. A prototype low-power and low-latency renderer using an off-the-shelf 3D card is discussed.

Wouter Pasman; Arjen Van Der Schaaf; Reginald L. Lagendijk; Frederik W. Jansen

1999-01-01

437

Accurate measurement of low insulator contamination levels  

Microsoft Academic Search

Accurate estimates of low levels of insulator contamination, in the range of 200 mg\\/m[sup 2] (0.02 mg\\/cm[sup 2]), can only be obtained if several minor errors in conventional surface contamination measurements are corrected. Many studies have noted severe reductions in electrical strength of high-voltage insulators in the presence of a light layer of ice. Field studies have also shown that

W. A. Chisholm; P. G. Buchan; T. Jarv

1994-01-01

438

Accurate Measurement of Glomerular Filtration Rate  

Microsoft Academic Search

\\u000a Measurement of the glomerular filtration rate (GFR) in patients with chronic renal disease has recently assumed increasing\\u000a importance. Responsibility for this evolutionary change can be directly traced to our understanding of the limitations of\\u000a plasma creatinine and creatinine clearance as markers of GFR (1,2) and the need for accurate and precise quantitation of GFR as potential therapies for progressive renal

Jeffrey G. Mulhern; Ronald D. Perrone

439

Cerebellar cortical efferents of the posterior lobe vermis in a prosimian primate (Galago) and the tree shrew (Tupaia).  

PubMed

The topographical organization of cerebellar cortical efferents of the posterior lobe vermis was studied in a prosimian primate (Galago senegalensis) and the tree shrew (Tupaia glis). Two patterns emerge; one which shows longitudinal zones of the entire vermis and a second which shows that induvidual lobules within the overall longitudinal pattern terminate in specific areas of the ipsilateral medial cerebellar nucleus (NM) and vestibular complix. The posterior lobe vermis consists of a narrow midline portion which projects bilaterally into the NM and a paramidline zone which projects only into the ipsilateral NM. These two zones are probably comparable to, and subdivisions of, Zone A of Voogd ('69). The lateral vermal zone projects primarily into the ipsilateral vestibular complex and/or interposed nuclei and appears to correspond to Zone B of Voogd ('69). Within this overall pattern individual lobules project into specific portions of the NM. From rostral to caudal (lobules VI to IX) terminal fields in the NM shift from dorsal and dorsomedial to ventral and ventrolatera. This is the inverse of the pattern of termination seen in the vestibular complex from lesions of the same lobules where from rostral to caudal (VI to IX) there are overlapping terminal fields from lateral to medial. With the exception of the narrow midline zone cerebellar corticonuclear projections of the posterior lobe vermis are ipsilateral. There is a more complex and more precise relationship between the posterior lobe vermis, NM and vestibular complex than previously suggested. PMID:808563

Haines, D E

1975-09-01

440

Event-tree analysis with imprecise probabilities.  

PubMed

Novel methods are proposed for dealing with event-tree analysis under imprecise probabilities, where one could measure chance or uncertainty without sharp numerical probabilities and express available evidence as upper and lower previsions (or expectations) of gambles (or bounded real functions). Sets of upper and lower previsions generate a convex set of probability distributions (or measures). Any probability distribution in this convex set should be considered in the event-tree analysis. This article focuses on the calculation of upper and lower bounds of the prevision (or the probability) of some outcome at the bottom of the event-tree. Three cases of given information/judgments on probabilities of outcomes are considered: (1) probabilities conditional to the occurrence of the event at the upper level; (2) total probabilities of occurrences, that is, not conditional to other events; (3) the combination of the previous two cases. Corresponding algorithms with imprecise probabilities under the three cases are explained and illustrated by simple examples. PMID:22053780

You, Xiaomin; Tonon, Fulvio

2011-11-06

441

Probability, Genetics and the Human Condition  

NSDL National Science Digital Library

This is a three day lesson plan, created by faculty members at the University of Virginia. The first day is an introduction to concepts in probability. The second day is an application of probability in the field of genetics. The third day is a time for students to expand their understanding of probability and genetics via short research project. The site includes resources, advice, and notes to the teacher. Probability topics include: law of large numbers, simple and compound events, sample size, sample space, and more.

2009-03-16

442

Construction of a gamma-distribution probability paper for straightening discharge probability curves  

Microsoft Academic Search

Conclusion  The Hazen probability paper presently being used for plotting discharge probability curves makes it possible to represent\\u000a the probability curve as a straight line only in the case of a normal distribution of the series. In the case of a skew distribution\\u000a of the series the probability curve has a bend. In such cases a special gamma-distribution probability paper should

F. F. Razzorenov

1980-01-01

443

Transiliac-transsacral screws for posterior pelvic stabilization.  

PubMed

Typical posterior pelvic fixation constructs use one or more large screws inserted from the lateral iliac cortex into the safe upper sacral ala or body. As a result of the deforming forces acting perpendicular to the implant axis, routine iliosacral screw fixation may not provide adequate stabilization, especially in certain unstable injuries. Longer iliosacral screws that traverse the entire upper sacrum and exit the contralateral iliac cortex may improve holding power and also stabilize concomitant contralateral posterior pelvic injuries. These transiliac-transsacral screws are reliably safe to insert using routine intraoperative fluoroscopy, and they provide durable fixation. These screws require careful preoperative planning and more precise technical attention during insertion because they pass through both sacral alar zones. Transiliac-transsacral screws may be particularly useful in the presence of osteoporosis, significant posterior pelvic instability including spinopelvic dissociation, patient obesity, anticipated noncompliant behavior, bilateral posterior pelvic injuries, and nonunion procedures. PMID:21577075

Gardner, Michael J; Routt, M L Chip

2011-06-01

444

Bending Waves of the Posterior Flagellum of Ceratium  

Microsoft Academic Search

Flagellar bending waves, as shown by multiple-flash photomicrographs of the posterior flagellum of Ceratium, are not sine waves. The bent regions are circular arcs; these regions are separated by short segments without bending.

C. J. Brokaw; Leigh Wright

1963-01-01

445

A Contoured, Posterior, Fiberglass-Epoxy Drop-Foot Brace.  

National Technical Information Service (NTIS)

The design, fabrication and field testing of a posterior, fiberglass-epoxy drop-foot brace are described. The advantages of this type of brace over the conventional brace are discussed from a subjective patient viewpoint. Particularly outstanding advantag...

J. T. Hill A. L. Fenwick

1968-01-01

446

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

447

Posterior relaxing retinotomies: analysis of anatomic and visual results.  

PubMed

Fifteen eyes with complicated retinal detachments--11 with proliferative vitreoretinopathy (C3 D3), 2 with posterior segment trauma, and 2 with inflammatory retinopathy--were treated with vitrectomy, membrane peeling, and large posterior retinotomy. All posterior relaxing retinotomies were circumferential, including temporal quadrants in all cases. With a minimum follow up of 6 months, 12 eyes (80%) were attached posterior to the retinotomy. Reproliferation resulted in redetachment in 3 eyes (20%). Visual acuity improved in 53%, remained unchanged in 20%, and decreased in 27%. Of the 11 eyes that achieved stable or improved visual acuity, 5 (45%) achieved 20/400 to 20/25 vision, 5 achieved counts fingers perception, and 1 patient remained stable at hand motion perception. Of all the eyes undergoing surgery, hypotony (intraocular pressure < 5 mm Hg) occurred in 6 eyes (40%); 3 of these were among the 12 eyes with attached retinas. PMID:1436968

Alturki, W A; Peyman, G A; Paris, C L; Blinder, K J; Desai, U R; Nelson, N C

1992-10-01

448

CASE REPORT Pan-Suture Synostosis After Posterior Vault Distraction  

PubMed Central

Objective: Posterior vault remodeling by distraction osteogenesis is a relatively new technique used for initial correction of turribrachycephaly in children with bicoronal craniosynostosis. We present a new potential complication from this procedure; a case of pan-suture synostosis subsequent to posterior vault distraction. Methods: We report an infant girl who presented with bicoronal synostosis in the setting of Saethre-Chotzen syndrome. She underwent posterior vault distraction and was distracted a total of 34 millimeters, with successful osteogenesis at the site. Results: One year postoperatively, the patient was found to have incidental, asymptomatic pan-suture synostosis on computed tomography. Conclusions: To our knowledge, this is the first reported case of delayed craniosynostosis after posterior vault distraction in the literature. The possible pathogenesis and significance of this case are discussed with a review of the current literature.

Chu, Katrina F.; Sullivan, Stephen R.; Taylor, Helena O.

2013-01-01

449

Acute posterior multifocal placoid pigment epitheliopathy and sarcoidosis.  

PubMed Central

We report on a patient with acute posterior multifocal placoid pigment epitheliopathy and sarcoidosis. A review of the literature suggests that sarcoidosis may occur more commonly in this condition than previously suspected. Images

Dick, D J; Newman, P K; Richardson, J; Wilkinson, R; Morley, A R

1988-01-01

450

Bending Waves of the Posterior Flagellum of Ceratium.  

PubMed

Flagellar bending waves, as shown by multiple-flash photomicrographs of the posterior flagellum of Ceratium, are not sine waves. The bent regions are circular arcs; these regions are separated by short segments without bending. PMID:17744109

Brokaw, C J; Wright, L

1963-11-29

451

The Architecture of the Choriocapillaris at the Posterior Pole.  

National Technical Information Service (NTIS)

The afferent and efferent vessels as well as the choriocapillaris in the human posterior pole, studied in flat preparations, paraffin sections, and Epon sections, formed relatively discrete units of organization which are called lobules. A lobule is a seg...

E. Torczynski M. O. M. Tso

1976-01-01

452

Posterior tibial tendon dysfunction and MR imaging in rheumatoid arthritis.  

PubMed

We present the case of a patient with long-standing rheumatoid arthritis and an acute onset of total dysfunction of the posterior tibial tendon. On MRI, a rupture of the tendon was apparent. Intraoperatively, however, massive tenosynovitis with stricture of the tendon was identified as the cause of posterior tibial tendon dysfunction. This case illustrates a pitfall in MRI imaging with potential diagnostic and therapeutic consequences. PMID:12120910

Hasler, Paul; Hintermann, Beat; Meier, Monika

2002-05-01

453

Posterior reversible encephalopathy syndrome revealing acute post-streptococcal glomerulonephritis.  

PubMed

A case of acute encephalopathy with posterior corticosubcortical vasogenic edema on magnetic resonance imaging is reported. Angiography showed cerebral arterial vasospasm. A diagnosis of acute post-streptococcal glomerulonephritis was made 2 days after admission. This report highlights the fact that acute post-streptococcal glomerulonephritis can be revealed by a posterior reversible encephalopathy syndrome and that cerebral vasospasm can concur with vasogenic edema in this condition. PMID:16901429

Aeby, Alec; David, Philippe; Fricx, Christophe; Jissendi, Patrice; Blecic, Serge; Van Bogaert, Patrick

2006-03-01

454

Posterior fossa arachnoid cysts and cerebellar tonsillar descent: short review  

Microsoft Academic Search

The objective of this study was to analyze the association of cerebellar tonsillar descent and syringomyelia in patients with\\u000a posterior fossa arachnoid cysts. We reviewed the medical records of ten patients (mean, age 33; range, 24–49 years) diagnosed\\u000a with posterior fossa arachnoid cyst and tonsillar descent. Symptoms evolved over a mean of 12 months (range, 6 months to 3 years).\\u000a Syringomyelia was present in

Marcelo Galarza; Antonio López López-Guerrero; Juan F. Martínez-Lage

2010-01-01

455

Reversible posterior leukoencephalopathy induced by carboplatin and etoposide  

Microsoft Academic Search

Reversible posterior leukoencephalopathy syndrome (RPLS) is a rare neurologic condition characterised by specific clinical\\u000a and radiologic findings. It usually manifests subacutely as insidious onset of headache, visual disturbance, altered consciousness\\u000a and seizures in association with MRI findings of posterior white matter vasogenic oedema. RPLS has been reported in a wide\\u000a variety of clinical settings. Hypertension, eclampsia, pre-eclampsia, renal impairment, autoimmune

S. A. Ryan; P. MacEneaney; S. P. O’Reilly; E. J. Moylan; D. G. Power

456

Diffusion tensor imaging of midline posterior fossa malformations  

Microsoft Academic Search

Background  Diffusion tensor imaging and tractography have been used to evaluate a variety of brain malformations. However, these studies have focused mainly on malformations involving the supratentorial compartments. There is a paucity of data on diffusion tensor imaging of posterior fossa malformations.Objective  To describe the color vector maps and modified or abnormal tracts of midline posterior fossa malformations.Materials and Methods  Diffusion tensor imaging

Elysa Widjaja; Susan Blaser; Charles Raybaud

2006-01-01

457

Dissecting Aneurysm of the Peripheral Posterior Inferior Cerebellar Artery  

Microsoft Academic Search

Summary  ¶?Dissecting aneurysms of intracranial posterior circulation have recently been shown to be less uncommon than previously\\u000a thought. However, those involving the posterior inferior cerebellar artery (PICA) and not vertebral artery at all are extremely\\u000a rare. We report here a case of a patient with a dissecting aneurysm of the lateral medullary segment of PICA which presented\\u000a as subarachnoid haemorrhage. The

Y. Kanou; K. Arita; K. Kurisu; F. Ikawa; K. Eguchi; S. Monden; K. Watanabe

2000-01-01

458

Is ossification of posterior longitudinal ligament an enthesopathy?  

Microsoft Academic Search

The purpose of this study was to investigate the relationship of ossification of posterior longitudinal ligament (OPLL) with\\u000a enthesis, the site where the posterior longitudinal ligament (PLL) attaches to the vertebral body, by multi-detector CT reconstruction\\u000a images. Twenty-nine patients with OPLL were studied. According to the plaques’ continuity to the vertebral body, OPLL plaques\\u000a were classified into two categories: “free”

Jian Chen; Dianwen Song; Xinwei Wang; Xiaolong Shen; Yang Li; Wen Yuan

459

Sonographic imaging of the posterior fossa utilizing the foramen magnum  

Microsoft Academic Search

In this essay, we describe our experience with a sonographic technique utilizing the foramen magnum to more clearly define\\u000a anatomy in the neonatal posterior fossa. This approach can be used as an additional problem-solving tool in neonates with\\u000a post-hemorrhagic hydrocephalus and a variety of posterior fossa abnormalities. The foramen magnum view is easily mastered\\u000a and produces diagnostic images with little

Christopher M. Brennan; George A. Taylor

2010-01-01

460

Posterior Retroperitoneoscopic Adrenalectomy: Lessons Learned within Five Years  

Microsoft Academic Search

.   Posterior retroperitoneoscopic adrenalectomy is one of the new endoscopic methods in endocrine surgery. In a prospective\\u000a clinical study 142 posterior retroperitoneoscopic adrenalectomies (72 right, 70 left) were performed in 130 patients (52 males,\\u000a 78 females, age 49.1 ± 14.9 years). Indications were primary adrenal tumors (unilateral, n= 118; bilateral, n= 2), adrenal metastases (n= 2), and bilateral ACTH-dependent hyperplasias

Martin K. Walz; Klaus Peitgen; Markus V. Walz; Rudolf Hoermann; Bernhard Saller; Reiner M. Giebler; Friedrich Jockenhövel; Thomas Philipp; Christoph E. Broelsch; Friedrich W. Eigler; Klaus Mann

2001-01-01

461

Patellar clunk syndrome after posterior stabilized total knee arthroplasty  

Microsoft Academic Search

Two hundred thirty-six posterior stabilized total knee arthroplasties (TKAs) were performed consecutively. Twenty-seven patellar clunk syndromes were identified in 25 patients. Insall-Salvati ratio, position of joint line, postoperative patellar height, and anterior-posterior position of tibial tray were measured. It was found that postoperative low-lying patella (P<.001) and anterior placement of tibial tray (P=.011) was associated with patellar clunk syndrome. Thirteen

Wai-Pan Yau; Jimmy W. K Wong; Kwong-Yuen Chiu; Tze-Pui Ng; Wai-Man Tang

2003-01-01

462

Instrumented Posterior Lumbar Interbody Fusion in Adult Spondylolisthesis  

Microsoft Academic Search

It is unclear whether using artificial cages increases fusion rates compared with use of bone chips alone in posterior lumbar\\u000a interbody fusion for patients with lumbar spondylolisthesis. We hypothesized artificial cages for posterior lumbar interbody\\u000a fusion would provide better clinical and radiographic outcomes than bone chips alone. We assumed solid fusion would provide\\u000a good clinical outcomes. We clinically and radiographically

Ching-Hsiao Yu; Chen-Ti Wang; Po-Quang Chen

2008-01-01

463

Horizontal eye movement disorders after posterior vermis infarctions.  

PubMed Central

The horizontal saccade, smooth pursuit, and vestibulo-ocular reflex gains were recorded in 19 patients with cerebellar infarction documented with MRI, and in a group of control subjects. Bilateral saccade hypometria and a decrease in ipsilateral smooth pursuit gain were found only in patients with a lesion affecting the posterior vermis. These results in humans support experimental findings suggesting that the posterior vermis controls both saccade accuracy and smooth pursuit velocity.

Vahedi, K; Rivaud, S; Amarenco, P; Pierrot-Deseilligny, C

1995-01-01

464

Updating Probabilities with Data and Moments  

NASA Astrophysics Data System (ADS)

We use the method of Maximum (relative) Entropy to process information in the form of observed data and moment constraints. The generic ``canonical'' form of the posterior distribution for the problem of simultaneous updating with data and moments is obtained. We discuss the general problem of non-commuting constraints, when they should be processed sequentially and when simultaneously. As an illustration, the multinomial example of die tosses is solved in detail for two superficially similar but actually very different problems.

Giffin, Adom; Caticha, Ariel

2007-11-01

465

Echocardiographic analysis of posterior mitral leaflet movement in mitral stenosis.  

PubMed Central

Echocardiographic analysis of the movement of the posterior mitral valve leaflet in 60 patients with lone mitral stenosis, 35 patients with aortic stenosis, and 18 patients with aortic and mitral stenosis showed a spectrum of initial posterior mitral valve leaflet movement in early diastole. The classical anterior movement was seen in 36 out of 60 patients with mitral stenosis (60%), and 8 out of 16 patients with aortic and mitral stenosis (50%). Normal posterior movement was present in all patients with lone aortic stenosis but was also seen in 10 patients (17%) with mitral stenosis and 6 patients (33%) with aortic and mitral stenosis. The remaining patients with mitral stenosis or aortic stenosis and mitral stenosis showed a biphasic type of initial movement. Patients with anterior movement had a mean calculated mitral valve area from cardiac catheterisation significantly smaller than the rest (P less than 0.001), but neither biphasic nor posterior movement excluded severe mitral stenosis. The distinction between patients with mitral stenosis and initial movement of the posterior mitral valve leaflet and patients with left ventricular discompliance is possible when there is sinus rhythm. Late diastolic anterior movement of the posterior mitral valve leaflet during atrial contraction is diagnostic of true mitral stenosis.

Shiu, M F; Jenkins, B S; Webb-Peploe, M M

1978-01-01

466

[Locked posterior dislocation of the hip: a case report].  

PubMed

Impaction fractures of the femoral head occurring after anterior or posterior hip dislocations are well described. However, locked posterior hip dislocation resulting in sinking of the posterior acetabular rim into the femoral head has hitherto been undescribed. A 26-year-old male patient presented with complaints of severe pain in the left thigh and marked limitation in the movements of the left hip two weeks after an in-car crash. He could only walk with crutches. Shortly after the accident, he was examined at another center with physical examination and plain radiographies and was given bed rest and medications for pain relief. Computed tomography demonstrated the locked posterior hip by the impact of the posterior acetabular rim against the femoral head. At surgery, the posterior acetabular rim was embedded in the anteromedial surface of the femoral head resulting in an osteochondral impaction fracture with a penetration depth of 12 mm. Due to wide destruction to the cartilage surface, an uncemented bipolar hemiarthroplasty was performed. After 28 months of follow-up, he had no complaints and hip movements were painless with full range of motion. PMID:17483654

Esenkaya, Irfan; Elmali, Nurzat

2007-01-01

467

Optimizing tooth form with direct posterior composite restorations  

PubMed Central

Advances in material sciences and technology have provided today's clinicians the strategies to transform the mechanistic approach of operative dentistry into a biologic philosophy. In the last three decades, composite resins have gone from being just an esthetically pleasing way of restoring Class III and Class IV cavities to become the universal material for both anterior and posterior situations as they closely mimic the natural esthetics while restoring the form of the human dentition. In order to enhance their success, clinicians have to rethink their protocol instead of applying the same restorative concepts and principles practiced with metallic restorations. Paralleling the evolution of posterior composite resin materials, cavity designs, restorative techniques and armamentarium have also developed rapidly to successfully employ composite resins in Class II situations. Most of the earlier problems with posterior composites such as poor wear resistance, polymerization shrinkage, postoperative sensitivity, predictable bonding to dentin, etc., have been overcome to a major extent. However, the clinically relevant aspect of achieving tight contacts in Class II situations has challenged clinicians the most. This paper reviews the evolution of techniques and recent developments in achieving predictable contacts with posterior composites. A Medline search was performed for articles on “direct posterior composite contacts.” The keywords used were “contacts and contours of posterior composites.” The reference list of each article was manually checked for additional articles of relevance.

Raghu, Ramya; Srinivasan, Raghu

2011-01-01

468

Atomic Transition Probabilities of Silicon. A Critical Compilation  

NASA Astrophysics Data System (ADS)

This compilation is the third in a series of updates to a critical compilation published in 1969 by Wiese et al. [Atomic Transition Probabilities, Vol. II: Sodium through Calcium, NSRDS-NBS Vol. 22 (U.S. GPO, Washington, D.C., 1969)]. Atomic transition probabilities have been critically evaluated and compiled for about 5800 spectral lines of silicon (nuclear charge Z=14). The cited values and their estimated uncertainties are based on our consideration of all available theoretical and experimental literature sources. All ionization stages (except for hydrogenic) are covered, and the data are presented in separate tables for each atom and ion. Separate listings are given for ``allowed'' (electric dipole) and ``forbidden'' (magnetic dipole plus electric and magnetic quadrupole) transitions. In each spectrum, lines are grouped into multiplets which are arranged in order of ascending lower and upper level energies, respectively. For each line, the emission transition probability Aki, the line strength S, and (for allowed lines) the absorption oscillator strength fik are given, together with the spectroscopic designation, the wavelength, the statistical weights, and the energy levels of the lower and upper states. The estimated relative uncertainties of the line strength are also indicated, as are the source citations. We include only those lines whose transition rates are deemed sufficiently accurate to qualify as reference values. Short introductions precede the tables for each ion.

Kelleher, D. E.; Podobedova, L. I.

2008-09-01

469

Probability and Statistics (MathPages)  

NSDL National Science Digital Library

More than 40 "informal notes" by Kevin Brown on probability and statistics: evaluating probabilities of Boolean events, area under the bell curve, N items distributed in M bins, dice rolling a given sum, a better lottery, meetings and birthdays, on random chords, and many more.

Brown, Kevin

2008-02-01

470

Laboratory-Tutorial Activities for Teaching Probability  

ERIC Educational Resources Information Center

|We report on the development of students' ideas of probability and probability density in a University of Maine laboratory-based general education physics course called "Intuitive Quantum Physics". Students in the course are generally math phobic with unfavorable expectations about the nature of physics and their ability to do it. We describe a…

Wittmann, Michael C.; Morgan, Jeffrey T.; Feeley, Roger E.

2006-01-01

471

Regulation probability method for gene selection  

Microsoft Academic Search

This paper proposes a novel method for gene selection. In the method, the gene regulation, an important mechanism of gene activities, is first introduced, and then the probabilities of gene regulation are estimated. These probabilities can be seen as the gene regulation information and can be used for gene selection. The applications to the leukemia dataset and the colon dataset

Hong-qiang Wang; De-shuang Huang

2006-01-01

472

Probability estimation for large-margin classifiers  

Microsoft Academic Search

Large margin classifiers have proven to be effective in delivering high predictive accuracy, particularly those focusing on the decision boundaries and bypassing the requirement of estimating the class probability given input for discrimination. As a result, these classifiers may not directly yield an estimated class probability, which is of interest itself. To overcome this difficulty, this article proposes a novel

Junhui Wang; Xiaotong Shen; Yufeng Liu

2008-01-01

473

Phonotactic Probabilities in Young Children's Speech Production  

ERIC Educational Resources Information Center

|This research explores the role of phonotactic probability in two-year-olds' production of coda consonants. Twenty-nine children were asked to repeat CVC non-words that were used as labels for pictures of imaginary animals. The CVC non-words were controlled for their phonotactic probabilities, neighbourhood densities, word-likelihood ratings, and…

Zamuner, Tania S.; Gerken, Louann; Hammond, Michael

2004-01-01

474

Thunderstorms and Hail Days Probabilities in Nevada.  

National Technical Information Service (NTIS)

A computer program was developed to provide probabilities for selected number of thunderstorm days in a month and in a year. In addition, probabilities for selected number of hail days in a year were determined. Two distribution models were tested in the ...

C. M. Sakamoto

1972-01-01

475

Probability models on horse-race outcomes  

Microsoft Academic Search

A number of models have been examined for modelling probability based on rankings. Most prominent among these are the gamma and normal probability models. The accuracy of these models in predicting the outcomes of horse races is investigated in this paper. The parameters of these models are estimated by the maximum likelihood method, using the information on win pool fractions.

MUKHTAR M. ALI

1998-01-01

476

Understanding Deutsch's probability in a deterministic multiverse  

Microsoft Academic Search

Difficulties over probability have often been considered fatal to the Everett interpretation of quantum mechanics. Here I argue that the Everettian can have everything she needs from `probability' without recourse to indeterminism, ignorance, primitive identity over time or subjective uncertainty: all she needs is a particular *rationality principle*. The decision-theoretic approach recently developed by Deutsch and Wallace claims to provide

Hilary Greaves

2003-01-01

477

Understanding Deutsch's probability in a deterministic multiverse  

Microsoft Academic Search

Difficulties over probability have often been considered fatal to the Everett interpretation of quantum mechanics. Here I argue that the Everettian can have everything she needs from ‘probability’ without recourse to indeterminism, ignorance, primitive identity over time or subjective uncertainty: all she needs is a particular rationality principle.The decision-theoretic approach recently developed by Deutsch and Wallace claims to provide just

H. Greaves

2004-01-01

478

The probability of contact with extraterrestrial life  

Microsoft Academic Search

The paper attempts to explain why technologically advanced extraterrestrial civilizations have not been detected. The discussion is restricted to living matter dependent on macromolecules with carbon-carbon chains and the probability of finding a physical environment similar to the terrestrial one. Drake's (1961) equation for the probable number of technological civilizations in a galaxy is reformulated so that the fractions of

N. H. Langton

1976-01-01

479

Math with a Sock: Probability and Fractions  

NSDL National Science Digital Library

In this excerpt from Bridges in Mathematics three exploratory activities are presented through which students learn to collect and display data, make predictions about probability, and write fractions. Each activity includes a probability experiment, visual representation of the data, and predictions about the data. Worksheets for the activities are included.

2000-01-01

480

Teaching Statistics and Probability: 1981 Yearbook.  

ERIC Educational Resources Information Center

|This 1981 yearbook of the National Council of Teachers of Mathematics (NCTM) offers classroom ideas for teaching statistics and probability, viewed as important topics in the school mathematics curriculum. Statistics and probability are seen as appropriate because they: (1) provide meaningful applications of mathematics at all levels; (2) provide…

Shulte, Albert P., Ed.; Smart, James R., Ed.

481

Average Transmission Probability of a Random Stack  

ERIC Educational Resources Information Center

|The transmission through a stack of identical slabs that are separated by gaps with random widths is usually treated by calculating the average of the logarithm of the transmission probability. We show how to calculate the average of the transmission probability itself with the aid of a recurrence relation and derive analytical upper and lower…

Lu, Yin; Miniatura, Christian; Englert, Berthold-Georg

2010-01-01

482

Bayesian generalized probability calculus for density matrices  

Microsoft Academic Search

One of the main concepts in quantum physics is a density matrix, which is a symmetric positive denite matrix of trace one. Finite probability distributions can be seen as a special case when the density matrix is restricted to be diagonal. We develop a probability calculus based on these more general distributions that in- cludes denitions of joints, conditionals and

Manfred K. Warmuth; Dima Kuzmin

2010-01-01

483

Remote state preparation with unit success probability  

Microsoft Academic Search

Remote state preparation is a secure and faithful method for transmitting known quantum states by means of local operation and classical communication. Existing protocols in the general case succeed just with probabilities of less than 100%. In this paper, we design a protocol to remotely prepare the most general single-qubit state that always succeeds. To achieve unit success probability, the

Ba An Nguyen; Thi Bich Cao; Van Don Nung; Jaewan Kim

2011-01-01

484

On probability distributions of nuclear cross sections  

Microsoft Academic Search

The nuclear cross section probability distributions in heavy nuclei are ; shown to be of simple form and to yield information on the reaction mechanisms ; and the structure of the scattering amplitude. The form of the probability ; distribution obtained provides a consistency check on the results obtained from ; cross section correlation functions. Scattering amplitudes are considered for

Torleif Eric Oskar Ericson

1963-01-01

485

Optimal sequential probability assignment for individual sequences  

Microsoft Academic Search

The problem of sequential probability assignment for individual sequences is investigated. The authors compare the probabilities assigned by any sequential scheme to the performance of the best “batch” scheme (model) in some class. For the class of finite-state schemes and other related families, they derive a deterministic performance bound, analogous to the classical (probabilistic) minimum description length (MDL) bound. It

Marcelo J. Weinberger; Neri Merhav; Meir Feder

1994-01-01

486

Spatiotemporal Relational Probability Trees: An Introduction  

Microsoft Academic Search

We introduce spatiotemporal relational probability trees (SRPTs), probability estimation trees for relational data that can vary in both space and time. The SRPT algo- rithm addresses the exponential increase in search complex- ity through sampling. We validate the SRPT using a sim- ulated data set and we empirically demonstrate the SRPT algorithm on two real-world data sets.

Amy Mcgovern; Nathan C. Hiers; Matthew W. Collier; David J. Gagne II; Rodger A. Brown

2008-01-01

487

Numerical inversion of probability generating functions  

Microsoft Academic Search

Random quantities of interest in operations research models can often be determinedconveniently in the form of transforms. Hence, numerical transform inversion can be an effectiveway to obtain desired numerical values of cumulative distribution functions, probability densityfunctions and probability mass functions. However, numerical transform inversion has not beenwidely used. This lack of use seems to be due, at least in part,

Joseph Abate; Ward Whitt

1992-01-01

488

Probability, Mathematics (Experimental): 5293.38.  

ERIC Educational Resources Information Center

|This guidebook on minimum content for a study of probability and its applications was designed for the student who has mastered second-year algebra. Covered in this booklet are sample spaces; tree diagrams, permutations, combinations, probability concepts and applications; and game theory. The course goals and performance objectives are…

Edwards, Raymond J.

489

Boundary Crossing Probabilities and Statistical Applications  

Microsoft Academic Search

This paper surveys recent results involving boundary crossing probabilities and related statistical applications. The first part is concerned with problems of sequential analysis, especially repeated significance tests and their application to sequential clinical trials involving survival data. The second part develops the probability theory motivated by the problems of Part 1. A method for computing first passage distributions of Brownian

David Siegmund

1986-01-01

490

Probability Issues in without Replacement Sampling  

ERIC Educational Resources Information Center

Sampling without replacement is an important aspect in teaching conditional probabilities in elementary statistics courses. Different methods proposed in different texts for calculating probabilities of events in this context are reviewed and their relative merits and limitations in applications are pinpointed. An alternative representation of…

Joarder, A. H.; Al-Sabah, W. S.

2007-01-01

491

Probability, clinical decision making and hypothesis testing  

PubMed Central

Few clinicians grasp the true concept of probability expressed in the ‘P value.’ For most, a statistically significant P value is the end of the search for truth. In fact, the opposite is the case. The present paper attempts to put the P value in proper perspective by explaining different types of probabilities, their role in clinical decision making, medical research and hypothesis testing.

Banerjee, A.; Jadhav, S. L.; Bhawalkar, J. S.

2009-01-01

492

Framing, probability distortions, and insurance decisions  

Microsoft Academic Search

A series of studies examines whether certain biases in probability assessments and perceptions of loss, previously found in experimental studies, affect consumers' decisions about insurance. Framing manipulations lead the consumers studied here to make hypothetical insurance-purchase choices that violate basic laws of probability and value. Subjects exhibit distortions in their perception of risk and framing effects in evaluating premiums and

John Hershey; Jacqueline Meszaros; Howard Kunreuther

1993-01-01

493

Call completion probability for a PCS network  

Microsoft Academic Search

In the emerging PCS networks, some calls may not be completed due to the handoff failure. It is very important to know the call completion probability for system design and performance evaluation. This probability depends on the distributions of the call holding times and the cell residence times. While the commonly used exponential distributions may provide good approximations for some

Y. Fang; I. Chlamtac; Yi-Bing Lin

1997-01-01

494

Rough probability and rough expected value models  

Microsoft Academic Search

Rough set theory is a new and effective mathematical theory used for processing incomplete, uncertain and vague data. In this paper, new set-theoretic operators - rough operators are proposed based on Pawlak rough set. On the basis of rough operators, a self-duality measure -rough probability is presented. On the rough probability space, rough variable, rough distribution, and rough expected value

Yi-Jun Fan; Da-Zeng Tian; Ming-Hu Ha

2008-01-01

495

Subjective probabilities for state dependent continuous utility  

Microsoft Academic Search

For the expected utility model with state dependent utilities, Karni, Schmeidler & Vind (1983, Econometrica) show how to recover uniquely the involved subjective probabilities if the preferences, contingent on a hypothetical probability distribution over the state space, are known. This they do for consequence spaces, consisting of lotteries on sets of prizes. This paper adapts their work to consequence spaces

Peter Wakker

1987-01-01

496

Ventilation-perfusion scanning and pulmonary angiography: correlation in clinical high-probability pulmonary embolism  

SciTech Connect

During a 3-year period, 173 clinically selected patients underwent pulmonary angiography to confirm or exclude acute pulmonary embolism. All patients had undergone ventilation-perfusion (V/Q) scanning (167 patients) or perfusion scanning alone (six) before angiography. Angiography was done because the results of the V/Q scanning did not satisfy the clinician's needs for certainty. The results of the V/Q and studies were compared to determine the relative accuracy of V/Q scanning in this clinical setting. Pulmonary embolism was found in seven (15%) of 47 patients with low-probability scans, 11 (32%) of 34 patients with intermediate-probability scans, 22 (39%) of 57 patients with indeterminate scans, and 23 (66%) of 35 patients with high-probability scans. In this clinically selected population, low-probability scans were more accurate in excluding pulmonary embolism than were high-probability scans in establishing that diagnosis.

Braun, S.D.; Newman, G.E.; Ford, K.; Miller, G.A.; Coleman, R.E.; Dunnick, N.R.

1984-11-01

497

Ventilation-perfusion scanning and pulmonary angiography: correlation in clinical high-probability pulmonary embolism  

SciTech Connect

During a 3-year period, 173 clinically selected patients underwent pulmonary angiography to confirm or exclude acute pulmonary embolism. All patients had undergone ventilation-perfusion (V/Q) scanning (167 patients) or perfusion scanning alone (six) before angiography. Angiography was done because the results of the V/Q scanning did not satisfy the clinician's needs for certainty. The results of the V/Q and angiographic studies were compared to determine the relative accuracy of V/Q scanning in this clinical setting. Pulmonary embolism was found in seven (15%) of 47 patients with low-probability scans, 11 (32%) of 34 patients with intermediate-probability scans, 22 (39%) of 57 patients with indeterminate scans, and 23 (66%) of 35 patients with high-probability scans. In this clinically selected population, low-probability scans were more accurate in excluding pulmonary embolism than were high-probability scans in establishing that diagnosis.

Braun, S.D.; Newman, G.E.; Ford, K.; Miller, G.A.; Coleman, R.E.; Dunnick, N.R.

1984-11-01

498

Testing the accuracy of Verbal Probability Scale for predicting short -term brand choice  

Microsoft Academic Search

In this research the predictive accuracy of the Verbal Probability Scale (VPS) in predicting four-week brand choice was compared to benchmarks from prior research and past behaviour. The results show that the measure of past behaviour provided the most accurate predictions at both brand and individual level. The exception to this was for the smallest brand in the market, where

Jenni Romaniuk

2004-01-01

499

Systematic review of cohort studies comparing surgical treatment for multilevel ossification of posterior longitudinal ligament: anterior vs posterior approach.  

PubMed

There have been no standards or guidelines for the treatment of ossification of posterior longitudinal ligament, especially multilevel ossification of posterior longitudinal ligament. The purpose of this study was to compare results of major surgical treatment for multilevel ossification of posterior longitudinal ligament. Databases including MEDLINE, EMBASE, the Cochrane library, and bibliographies of identified and review articles were searched to find randomized, controlled trials or retrospective cohort studies comparing anterior and posterior approach from 1980 to December 2010. Approximately 1375 articles were found initially, 92 abstracts were screened, 23 articles were retrieved in full; 3 studies were included in the review. No randomized, controlled studies were identified. Because all the studies included in this study are cohort studies with disparity of surgical interventions, heterogeneity of outcome measures and different qualities, we were unable to perform a meta-analysis. All comparison studies are retrospective cohort studies, comparing surgical outcomes of anterior approach (corpectomy and fusion) with that of posterior approach (laminoplasty or laminectomy) for the treatment of multilevel ossification of posterior longitudinal ligament in the cervical spine. A systematic review of retrospective cohort studies was performed to determine which surgical treatment is the most effective in patients with multilevel ossification of posterior longitudinal ligament. Definitive conclusions regarding the surgical treatment of multilevel ossification of posterior longitudinal ligament could not be made in this article. Multilevel corpectomy and fusion are more technical and have a significantly higher rate of cerebrospinal fluid leakage and graft, instrumentation related complications. A well-designed, prospective, randomized controlled, multicenter trial is needed. PMID:21815583

Xu, JunJie; Zhang, Kai; Ma, XiangYang; Yin, QingShui; Wu, ZengHui; Xia, Hong; Wang, ZhiYun

2011-08-08

500

New law requires 'medically accurate' lesson plans.  

PubMed

The California Legislature has passed a bill requiring all textbooks and materials used to teach about AIDS be medically accurate and objective. Statements made within the curriculum must be supported by research conducted in compliance with scientific methods, and published in peer-reviewed journals. Some of the current lesson plans were found to contain scientifically unsupported and biased information. In addition, the bill requires material to be "free of racial, ethnic, or gender biases." The legislation is supported by a wide range of interests, but opposed by the California Right to Life Education Fund, because they believe it discredits abstinence-only material. PMID:11366835

1999-09-17