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Sample records for centroid finding method

  1. Centroid finding method for position-sensitive detectors

    Radeka, V.; Boie, R.A.

    1979-10-01

    A new centroid finding method for all detectors where the signal charge is collected or induced on strips of wires, or on subdivided resistive electrodes, is presented. The centroid of charge is determined by convolution of the sequentially switched outputs from these subdivisions or from the strips with a linear centroid finding filter. The position line width is inversely proportional to N/sup 3/2/, where N is the number of subdivisions.

  2. A new Initial Centroid finding Method based on Dissimilarity Tree for K-means Algorithm

    Kumar, Abhishek; Gupta, Suresh Chandra

    2015-01-01

    Cluster analysis is one of the primary data analysis technique in data mining and K-means is one of the commonly used partitioning clustering algorithm. In K-means algorithm, resulting set of clusters depend on the choice of initial centroids. If we can find initial centroids which are coherent with the arrangement of data, the better set of clusters can be obtained. This paper proposes a method based on the Dissimilarity Tree to find, the better initial centroid as well as every bit more acc...

  3. Finding binary active galactic nuclei candidates by the centroid shift in imaging surveys II. Testing the method with SDSS J233635.75-010733.7

    Liu, Yuan

    2016-01-01

    In Liu (2015), we propose selecting binary active galactic nuclei (AGNs) candidates using the centroid shift of the images, which is induced by the non-synchronous variations of the two nuclei. In this paper, a known binary AGN (SDSS J233635.75-010733.7) is employed to verify the ability of this method. Using 162 exposures in the $R$ band of \\textit{Palomar Transient Factory} (PTF), an excess of dispersion in the positional distribution of the binary AGN is detected, though the two nuclei cannot be resolved in the images of PTF. We also propose a new method to compare the position of the binary AGN in PTF $g$ and $R$ band and find the difference is highly significant even only with 20 exposures. This new method is efficient for two nuclei with different spectral energy distributions, e.g., type I + type II AGN or off-set AGN. Large-scale surveys, e.g., the Panoramic Survey Telescope and Rapid Response System and the Large Synoptic Survey Telescope, are expected to discover a large sample of binary AGN candida...

  4. Multiple centroid method to evaluate the adaptability of alfalfa genotypes

    Moysés Nascimento

    2015-02-01

    Full Text Available This study aimed to evaluate the efficiency of multiple centroids to study the adaptability of alfalfa genotypes (Medicago sativa L.. In this method, the genotypes are compared with ideotypes defined by the bissegmented regression model, according to the researcher's interest. Thus, genotype classification is carried out as determined by the objective of the researcher and the proposed recommendation strategy. Despite the great potential of the method, it needs to be evaluated under the biological context (with real data. In this context, we used data on the evaluation of dry matter production of 92 alfalfa cultivars, with 20 cuttings, from an experiment in randomized blocks with two repetitions carried out from November 2004 to June 2006. The multiple centroid method proved efficient for classifying alfalfa genotypes. Moreover, it showed no unambiguous indications and provided that ideotypes were defined according to the researcher's interest, facilitating data interpretation.

  5. Gaussian Analytic Centroiding method of star image of star tracker

    Wang, Haiyong; Xu, Ershuai; Li, Zhifeng; Li, Jingjin; Qin, Tianmu

    2015-11-01

    The energy distribution of an actual star image coincides with the Gaussian law statistically in most cases, so the optimized processing algorithm about star image centroiding should be constructed also by following Gaussian law. For a star image spot covering a certain number of pixels, the marginal distribution of the gray accumulation on rows and columns are shown and analyzed, based on which the formulas of Gaussian Analytic Centroiding method (GAC) are deduced, and the robustness is also promoted due to the inherited filtering effect of gray accumulation. Ideal reference star images are simulated by the PSF (point spread function) with integral form. Precision and speed tests for the Gaussian Analytic formulas are conducted under three scenarios of Gaussian radius (0.5, 0.671, 0.8 pixel), The simulation results show that the precision of GAC method is better than that of the other given algorithms when the Gaussian radius is not bigger than 5 × 5 pixel window, a widely used parameter. Above all, the algorithm which consumes the least time is still the novel GAC method. GAC method helps to promote the comprehensive performance in the attitude determination of a star tracker.

  6. Electronic lifetime measurements with a Ge(Li) detector using the centroid-shift method

    The centroid-shift method was applied to lifetime measurements using a pulsed beam. A time-centroid spectrum and a mean-life spectrum were created automatically with a minimum of human interference. The method is illustrated with the 98Mo(α,3n)99Ru reaction, in which an isomeric state in 99Ru was found. (Auth.)

  7. Star sub-pixel centroid calculation based on multi-step minimum energy difference method

    Wang, Duo; Han, YanLi; Sun, Tengfei

    2013-09-01

    The star's centroid plays a vital role in celestial navigation, star images which be gotten during daytime, due to the strong sky background, have a low SNR, and the star objectives are nearly submerged in the background, takes a great trouble to the centroid localization. Traditional methods, such as a moment method, weighted centroid calculation method is simple but has a big error, especially in the condition of a low SNR. Gaussian method has a high positioning accuracy, but the computational complexity. Analysis of the energy distribution in star image, a location method for star target centroids based on multi-step minimum energy difference is proposed. This method uses the linear superposition to narrow the centroid area, in the certain narrow area uses a certain number of interpolation to pixels for the pixels' segmentation, and then using the symmetry of the stellar energy distribution, tentatively to get the centroid position: assume that the current pixel is the star centroid position, and then calculates and gets the difference of the sum of the energy which in the symmetric direction(in this paper we take the two directions of transverse and longitudinal) and the equal step length(which can be decided through different conditions, the paper takes 9 as the step length) of the current pixel, and obtain the centroid position in this direction when the minimum difference appears, and so do the other directions, then the validation comparison of simulated star images, and compare with several traditional methods, experiments shows that the positioning accuracy of the method up to 0.001 pixel, has good effect to calculate the centroid of low SNR conditions; at the same time, uses this method on a star map which got at the fixed observation site during daytime in near-infrared band, compare the results of the paper's method with the position messages which were known of the star, it shows that :the multi-step minimum energy difference method achieves a better

  8. Comparison of performance of some common Hartmann-Shack centroid estimation methods

    Thatiparthi, C.; Ommani, A.; Burman, R.; Thapa, D.; Hutchings, N.; Lakshminarayanan, V.

    2016-03-01

    The accuracy of the estimation of optical aberrations by measuring the distorted wave front using a Hartmann-Shack wave front sensor (HSWS) is mainly dependent upon the measurement accuracy of the centroid of the focal spot. The most commonly used methods for centroid estimation such as the brightest spot centroid; first moment centroid; weighted center of gravity and intensity weighted center of gravity, are generally applied on the entire individual sub-apertures of the lens let array. However, these processes of centroid estimation are sensitive to the influence of reflections, scattered light, and noise; especially in the case where the signal spot area is smaller compared to the whole sub-aperture area. In this paper, we give a comparison of performance of the commonly used centroiding methods on estimation of optical aberrations, with and without the use of some pre-processing steps (thresholding, Gaussian smoothing and adaptive windowing). As an example we use the aberrations of the human eye model. This is done using the raw data collected from a custom made ophthalmic aberrometer and a model eye to emulate myopic and hyper-metropic defocus values up to 2 Diopters. We show that the use of any simple centroiding algorithm is sufficient in the case of ophthalmic applications for estimating aberrations within the typical clinically acceptable limits of a quarter Diopter margins, when certain pre-processing steps to reduce the impact of external factors are used.

  9. Statistical analysis of x-ray stress measurement by centroid method

    The X-ray technique allows a nondestructive and rapid measurement of residual stresses in metallic materials. The centroid method has an advantage over other X-ray methods in that it can determine the angular position of a diffraction line, from which the stress is calculated, even with an asymmetrical line profile. An equation for the standard deviation of the angular position of a diffraction line, σsub(p), caused by statistical fluctuation was derived, which is a fundamental source of scatter in X-ray stress measurements. This equation shows that an increase of X-ray counts by a factor of k results in a decrease of σsub(p) by a factor of 1/√k. It also shows that σsub(p) increases rapidly as the angular range used in calculating the centroid increases. It is therefore important to calculate the centroid using the narrow angular range between the two ends of the diffraction line where it starts to deviate from the straight background line. By using quenched structural steels JIS S35C and S45C, the residual stresses and their standard deviations were calculated by the centroid, parabola, Gaussian curve, and half-width methods, and the results were compared. The centroid of a diffraction line was affected greatly by the background line used. The standard deviation of the stress measured by the centroid method was found to be the largest among the four methods. (author)

  10. Generalized centroid shift method for lifetime measurements in heavy ion reactions

    Andrejtscheff, W.; Senba, M.; Tsoupas, N.; Ding, Z.Z. (Rutgers - the State Univ., New Brunswick, NJ (USA). Dept. of Physics and Astronomy)

    1982-12-15

    An application of the generalized centroid shift method for lifetime measurements in the nano-second and subnanosecond region in HI reactions on the Rutgers tandem is described. Delayed ..gamma gamma..-coincidence measurements using plastic scintillators (start) and a germanium detector (stop) are discussed. Details of the analysis including treatment of the time background (random coincidences) and the choice of range of analysis of the time distributions are considered.

  11. Ranking Fuzzy Numbers with a Distance Method using Circumcenter of Centroids and an Index of Modality

    P. Phani Bushan Rao

    2011-01-01

    Full Text Available Ranking fuzzy numbers are an important aspect of decision making in a fuzzy environment. Since their inception in 1965, many authors have proposed different methods for ranking fuzzy numbers. However, there is no method which gives a satisfactory result to all situations. Most of the methods proposed so far are nondiscriminating and counterintuitive. This paper proposes a new method for ranking fuzzy numbers based on the Circumcenter of Centroids and uses an index of optimism to reflect the decision maker's optimistic attitude and also an index of modality that represents the neutrality of the decision maker. This method ranks various types of fuzzy numbers which include normal, generalized trapezoidal, and triangular fuzzy numbers along with crisp numbers with the particularity that crisp numbers are to be considered particular cases of fuzzy numbers.

  12. A multi-resolution method for climate system modeling: application of Spherical Centroidal A multi-resolution method for climate system modeling: Application of Spherical Centroidal Voroni Tessellations

    Ringler, Todd D [Los Alamos National Laboratory; Gunzburger, Max [FLORIDA STATE UNIV; Ju, Lili [UNIV OF SOUTH CAROLINA

    2008-01-01

    During the next decade and beyond, climate system models will be challenged to resolve scales and processes that are far beyond their current scope. Each climate system component has its prototypical example of an unresolved process that may strongly influence the global climate system, ranging from eddy activity within ocean models, to ice streams within ice sheet models, to surface hydrological processes within land system models, to cloud processes within atmosphere models. These new demands will almost certainly result in the develop of multi-resolution schemes that are able, at least regional to faithfully simulate these fine-scale processes. Spherical Centroidal Voronoi Tessellations (SCVTs) offer one potential path toward the development of robust, multi-resolution climate system component models, SCVTs allow for the generation of high quality Voronoi diagrams and Delaunay triangulations through the use of an intuitive, user-defined density function, each of the examples provided, this method results in high-quality meshes where the quality measures are guaranteed to improve as the number of nodes is increased. Real-world examples are developed for the Greenland ice sheet and the North Atlantic ocean. Idealized examples are developed for ocean-ice shelf interaction and for regional atmospheric modeling. In addition to defining, developing and exhibiting SCVTs, we pair this mesh generation technique with a previously developed finite-volume method. Our numerical example is based on the nonlinear shallow-water equations spanning the entire surface of the sphere. This example is used to elucidate both the potential benefits of this multi-resolution method and the challenges ahead.

  13. An improved Q estimation approach: the weighted centroid frequency shift method

    Li, Jingnan; Wang, Shangxu; Yang, Dengfeng; Dong, Chunhui; Tao, Yonghui; Zhou, Yatao

    2016-06-01

    Seismic wave propagation in subsurface media suffers from absorption, which can be quantified by the quality factor Q. Accurate estimation of the Q factor is of great importance for the resolution enhancement of seismic data, precise imaging and interpretation, and reservoir prediction and characterization. The centroid frequency shift method (CFS) is currently one of the most commonly used Q estimation methods. However, for seismic data that contain noise, the accuracy and stability of Q extracted using CFS depend on the choice of frequency band. In order to reduce the influence of frequency band choices and obtain Q with greater precision and robustness, we present an improved CFS Q measurement approach—the weighted CFS method (WCFS), which incorporates a Gaussian weighting coefficient into the calculation procedure of the conventional CFS. The basic idea is to enhance the proportion of advantageous frequencies in the amplitude spectrum and reduce the weight of disadvantageous frequencies. In this novel method, we first construct a Gauss function using the centroid frequency and variance of the reference wavelet. Then we employ it as the weighting coefficient for the amplitude spectrum of the original signal. Finally, the conventional CFS is adopted for the weighted amplitude spectrum to extract the Q factor. Numerical tests of noise-free synthetic data demonstrate that the WCFS is feasible and efficient, and produces more accurate results than the conventional CFS. Tests for noisy synthetic data indicate that the new method has better anti-noise capability than the CFS. The application to field vertical seismic profile (VSP) data further demonstrates its validity5.

  14. Two tree-formation methods for fast pattern search using nearest-neighbour and nearest-centroid matching

    Schomaker, Lambertus; Mangalagiu, D.; Vuurpijl, Louis; Weinfeld, M.; Schomaker, Lambert; Vuurpijl, Louis

    2000-01-01

    This paper describes tree­based classification of character images, comparing two methods of tree formation and two methods of matching: nearest neighbor and nearest centroid. The first method, Preprocess Using Relative Distances (PURD) is a tree­based reorganization of a flat list of patterns, desi

  15. Comparison of pure and 'Latinized' centroidal Voronoi tessellation against various other statistical sampling methods

    A recently developed centroidal Voronoi tessellation (CVT) sampling method is investigated here to assess its suitability for use in statistical sampling applications. CVT efficiently generates a highly uniform distribution of sample points over arbitrarily shaped M-dimensional parameter spaces. On several 2-D test problems CVT has recently been found to provide exceedingly effective and efficient point distributions for response surface generation. Additionally, for statistical function integration and estimation of response statistics associated with uniformly distributed random-variable inputs (uncorrelated), CVT has been found in initial investigations to provide superior points sets when compared against latin-hypercube and simple-random Monte Carlo methods and Halton and Hammersley quasi-random sequence methods. In this paper, the performance of all these sampling methods and a new variant ('Latinized' CVT) are further compared for non-uniform input distributions. Specifically, given uncorrelated normal inputs in a 2-D test problem, statistical sampling efficiencies are compared for resolving various statistics of response: mean, variance, and exceedence probabilities

  16. A walk-free centroid method for lifetime measurements with pulsed beams

    A delayed-coincidence lifetime measurement method based on a comparison of walk-free centroids of time spectra is presented. The time is measured between the cyclotron RF signal and the pulse from a plastic scintillation detector followed by a fixed energy selection. The events to be time-analyzed are selected from the associated charge-particle spectrum of a silicon detector which is operated in coincidence with the scintillator, i.e., independently of the formation of the signal containing the time information. With this technique, with the micropulse FWHM of typically 500 to 700 ps, half-lives down to the 10 ps region can be measured. The following half-lives are obtained with the new method: 160+-6 ps for the 2032 keV level in 209Pb; 45+-10 ps and 160+-20 ps for the 1756.8 keV (02+) and 2027.3 keV (03+) levels in 116Sn, respectively. (author)

  17. Localization Methods of Weighted Centroid of dBZ on Weather-Radar Echo Maps in Vector Format

    Xue-tao Yu

    2013-02-01

    Full Text Available Fast generation of weather-radar echo maps in vector format and accurate localization of weighted centroid of dBZ (dBZ stands for decibels of reflectivity of a radar signal reflected off a remote object are the basis of studying the characteristic tracking algorithms which are based on the vector echoes. The authors principally studied the approach to generating the vector echo map, and discussed the localization methods of weighted centroid of dBZ on vector echo maps. First, based on the traditional calculation method on raster echo data, some new localization methods of weighted centroid of dBZ on vector echo data were proposed by considering the weights of features’ area and distance from their location to radar center. Second, taking the base reflectivity products of CINRAD/SA weather radar in Meizhou city of China as data sources, they illustrated the storage structure of this type of echo data and studied the drawing mode of changing this type of data into vector format files under the polar coordinate system in detail. Third, using the same vector echo maps created by the above method, the weighted centroid of the same area was calculated by the above localization methods. In the end, Compared with the calculated value of the same area by traditional method which is based on raster echo maps, the three new calculated results and the sources of error were analyzed in detail and two conclusions were drawn: the echo’s precision in vector format is much higher than that in raster format and it is more accurate to take the features’ area and distance to radar center as weights during the calculation of weighted centroid of dBZ on echo maps in vector format.

  18. A multi-resolution method for climate system modeling: application of spherical centroidal Voronoi tessellations

    Ringler, Todd [Los Alamos National Laboratory; Ju, Lili [University of South Carolina; Gunzburger, Max [Florida State University

    2008-01-01

    During the next decade and beyond, climate system models will be challenged to resolve scales and processes that are far beyond their current scope. Each climate system component has its prototypical example of an unresolved process that may strongly influence the global climate system, ranging from eddy activity within ocean models, to ice streams within ice sheet models, to surface hydrological processes within land system models, to cloud processes within atmosphere models. These new demands will almost certainly result in the develop of multiresolution schemes that are able, at least regionally, to faithfully simulate these fine-scale processes. Spherical centroidal Voronoi tessellations (SCVTs) offer one potential path toward the development of a robust, multiresolution climate system model components. SCVTs allow for the generation of high quality Voronoi diagrams and Delaunay triangulations through the use of an intuitive, user-defined density function. In each of the examples provided, this method results in high-quality meshes where the quality measures are guaranteed to improve as the number of nodes is increased. Real-world examples are developed for the Greenland ice sheet and the North Atlantic ocean. Idealized examples are developed for ocean–ice shelf interaction and for regional atmospheric modeling. In addition to defining, developing, and exhibiting SCVTs, we pair this mesh generation technique with a previously developed finite-volume method. Our numerical example is based on the nonlinear, shallow water equations spanning the entire surface of the sphere. This example is used to elucidate both the potential benefits of this multiresolution method and the challenges ahead.

  19. The Generalized Centroid Difference method for lifetime measurements via γ-γ coincidences using large fast-timing arrays

    Régis J.-M.

    2015-01-01

    Full Text Available A novel method for direct electronic “fast-timing” lifetime measurements of nuclear excited states via γ-γ coincidences using an array equipped with N very fast high-resolution LaBr3(Ce scintillator detectors is presented. The generalized centroid difference method provides two independent “start” and “stop” time spectra obtained without any correction by a superposition of the N(N – 1/2 calibrated γ-γ time difference spectra of the N detector fast-timing system. The two fast-timing array time spectra correspond to a forward and reverse gating of a specific γ-γ cascade and the centroid difference as the time shift between the centroids of the two time spectra provides a picosecond-sensitive mirror-symmetric observable of the set-up. The energydependent mean prompt response difference between the start and stop events is calibrated and used as a single correction for lifetime determination. These combined fast-timing array mean γ-γ zero-time responses can be determined for 40 keV < Eγ < 1.4 MeV with a precision better than 10 ps using a 152Eu γ-ray source. The new method is described with examples of (n,γ and (n,f,γ experiments performed at the intense cold-neutron beam facility PF1B of the Institut Laue-Langevin in Grenoble, France, using 16 LaBr3(Ce detectors within the EXILL&FATIMA campaign in 2013. The results are discussed with respect to possible systematic errors induced by background contributions.

  20. Centroid Localization of Uncooperative Nodes in Wireless Networks Using a Relative Span Weighting Method

    Christine Laurendeau

    2010-01-01

    Full Text Available Increasingly ubiquitous wireless technologies require novel localization techniques to pinpoint the position of an uncooperative node, whether the target is a malicious device engaging in a security exploit or a low-battery handset in the middle of a critical emergency. Such scenarios necessitate that a radio signal source be localized by other network nodes efficiently, using minimal information. We propose two new algorithms for estimating the position of an uncooperative transmitter, based on the received signal strength (RSS of a single target message at a set of receivers whose coordinates are known. As an extension to the concept of centroid localization, our mechanisms weigh each receiver's coordinates based on the message's relative RSS at that receiver, with respect to the span of RSS values over all receivers. The weights may decrease from the highest RSS receiver either linearly or exponentially. Our simulation results demonstrate that for all but the most sparsely populated wireless networks, our exponentially weighted mechanism localizes a target node within the regulations stipulated for emergency services location accuracy.

  1. A novel, view-independent method for strain mapping in myocardial elastography: eliminating angle and centroid dependence

    Robust indices of regional and global cardiac function are a key factor in detection and treatment of heart disease as well as understanding of the fundamental mechanisms of a healthy heart. Myocardial elastography provides a noninvasive method for imaging and measuring displacement and strain of the myocardium for the early detection of cardiovascular disease. However, two-dimensional in-plane axial and lateral strains measured depend on the sonographic view used. This becomes especially critical in a clinical setting and may induce large variations in the measured strains, potentially leading to false diagnoses. A novel method in myocardial elastography is proposed for eliminating this view dependence by deriving the polar, principal and classified principal strains. The performance of the proposed methodology is assessed by employing 3D finite-element left-ventricular models of a control and an ischemic canine heart. Although polar strains are angle-independent, they are sensitive to the selected reference coordinate system, which requires the definition of a centroid of the left ventricle (LV). In contrast, principal strains derived through eigenvalue decomposition exhibit the inherent characteristic of coordinate system independence, offering view (i.e., angle and centroid)-independent strain measurements. Classified principal strains are obtained by assigning the principal components in the physical ventricular coordinate system. An extensive strain analysis illustrates the improvement in interpretation and visualization of the full-field myocardial deformation by using the classified principal strains, clearly depicting the ischemic and non-ischemic regions. Strain maps, independent of sonographic views and imaging planes, that can be used to accurately detect regional contractile dysfunction are demonstrated

  2. Comparison of pure and 'Latinized' centroidal Voronoi tessellation against various other statistical sampling methods

    Romero, Vicente J. [Model Validation and Uncertainty Quantification Department, Sandia National Laboratories, Albuquerque, NM 87185-0828 (United States)]. E-mail: vjromer@sandia.gov; Burkardt, John V. [School of Computational Science and Information Technology, Florida State University, Tallahassee, FL 32306-4120 (United States)]. E-mail: burkardt@csit.fsu.edu; Gunzburger, Max D. [School of Computational Science and Information Technology, Florida State University, Tallahassee, FL 32306-4120 (United States)]. E-mail: gunzburg@csit.fsu.edu; Peterson, Janet S. [School of Computational Science and Information Technology, Florida State University, Tallahassee, FL 32306-4120 (United States)]. E-mail: jspeters@csit.fsu.edu

    2006-10-15

    A recently developed centroidal Voronoi tessellation (CVT) sampling method is investigated here to assess its suitability for use in statistical sampling applications. CVT efficiently generates a highly uniform distribution of sample points over arbitrarily shaped M-dimensional parameter spaces. On several 2-D test problems CVT has recently been found to provide exceedingly effective and efficient point distributions for response surface generation. Additionally, for statistical function integration and estimation of response statistics associated with uniformly distributed random-variable inputs (uncorrelated), CVT has been found in initial investigations to provide superior points sets when compared against latin-hypercube and simple-random Monte Carlo methods and Halton and Hammersley quasi-random sequence methods. In this paper, the performance of all these sampling methods and a new variant ('Latinized' CVT) are further compared for non-uniform input distributions. Specifically, given uncorrelated normal inputs in a 2-D test problem, statistical sampling efficiencies are compared for resolving various statistics of response: mean, variance, and exceedence probabilities.

  3. Alteração no método centroide de avaliação da adaptabilidade genotípica Alteration of the centroid method to evaluate genotypic adaptability

    Moysés Nascimento

    2009-03-01

    Full Text Available O objetivo deste trabalho foi alterar o método centroide de avaliação da adaptabilidade e estabilidade fenotípica de genótipos, para deixá-lo com maior sentido biológico e melhorar aspectos quantitativos e qualitativos de sua análise. A alteração se deu pela adição de mais três ideótipos, definidos de acordo com valores médios dos genótipos nos ambientes. Foram utilizados dados provenientes de um experimento sobre produção de matéria seca de 92 genótipos de alfafa (Medicago sativa realizado em blocos ao acaso, com duas repetições. Os genótipos foram submetidos a 20 cortes, no período de novembro de 2004 a junho de 2006. Cada corte foi considerado um ambiente. A inclusão dos ideótipos de maior sentido biológico (valores médios nos ambientes resultou em uma dispersão gráfica em forma de uma seta voltada para a direita, na qual os genótipos mais produtivos ficaram próximos à ponta da seta. Com a alteração, apenas cinco genótipos foram classificados nas mesmas classes do método centroide original. A figura em forma de seta proporciona uma comparação direta dos genótipos, por meio da formação de um gradiente de produtividade. A alteração no método mantém a facilidade de interpretação dos resultados para a recomendação dos genótipos presente no método original e não permite duplicidade de interpretação dos resultados.ABSTRACT The objective of this work was to modify the centroid method of evaluation of phenotypic adaptability and the phenotype stability of genotypes in order for the method to make greater biological sense and improve its quantitative and qualitative performance. The method was modified by means of the inclusion of three additional ideotypes defined in accordance with the genotypes' average yield in the environments tested. The alfalfa (Medicago sativa L. forage yield of 92 genotypes was used. The trial had a randomized block design, with two replicates, and the data were used to

  4. A Reference Point Construction Method Using Mobile Terminals and the Indoor Localization Evaluation in the Centroid Method

    Takahiro Yamaguchi

    2015-05-01

    Full Text Available As smartphones become widespread, a variety of smartphone applications are being developed. This paper proposes a method for indoor localization (i.e., positioning that uses only smartphones, which are general-purpose mobile terminals, as reference point devices. This method has the following features: (a the localization system is built with smartphones whose movements are confined to respective limited areas. No fixed reference point devices are used; (b the method does not depend on the wireless performance of smartphones and does not require information about the propagation characteristics of the radio waves sent from reference point devices, and (c the method determines the location at the application layer, at which location information can be easily incorporated into high-level services. We have evaluated the level of localization accuracy of the proposed method by building a software emulator that modeled an underground shopping mall. We have confirmed that the determined location is within a small area in which the user can find target objects visually.

  5. Centroid Based Text Clustering

    Priti Maheshwari

    2010-09-01

    Full Text Available Web mining is a burgeoning new field that attempts to glean meaningful information from natural language text. Web mining refers generally to the process of extracting interesting information and knowledge from unstructured text. Text clustering is one of the important Web mining functionalities. Text clustering is the task in which texts are classified into groups of similar objects based on their contents. Current research in the area of Web mining is tacklesproblems of text data representation, classification, clustering, information extraction or the search for and modeling of hidden patterns. In this paper we propose for mining large document collections it is necessary to pre-process the web documents and store the information in a data structure, which is more appropriate for further processing than a plain web file. In this paper we developed a php-mySql based utility to convert unstructured web documents into structured tabular representation by preprocessing, indexing .We apply centroid based web clustering method on preprocessed data. We apply three methods for clustering. Finally we proposed a method that can increase accuracy based on clustering ofdocuments.

  6. Application example: Preliminary Results of ISOLA use to find moment tensor solutions and centroid depth applied to aftershocks of Mw=8.8 February 27 2010, Maule Earthquake

    Nacif, S. V.; Sanchez, M. A.

    2013-05-01

    We selected seven aftershocks from Maule earthquake between 33.5°S to 35°S from May to September to find single source inversion. The data were provided by XY Chile Ramp Experiment* which was deployed after great Maule earthquake. Waveform data are from 13 broad band stations chosen from the 58 broad band stations deployed by IRIS-PASCAL from April to September 2010. Stations are placed above the normal subduction section south of ~33.5°S. Events were located with an iterative software called Hypocenter using one dimensional local model, obtained above for the forearc region between 33°S to 35°S. We used ISOLA which is a fortran code with a Matlab interface to obtain moment tensors solutions, optimum position and time of the subevents. Values depth obtained by a grid search of centroid position show range values which are compatibles with the interplate seismogenic zone. Double-Couple focal mechanism solutions (Figure 1) show 4 thrust events which can be associated with that zone. However, only one of them has strike, dip and rake of 358°, 27° and 101 respectively, appropriate to be expected for interplate seismogenic zone. On the other hand, the other 3 events show strike and normal double-couple focal mechanism solutions (Figure 1). This last topic makes association to those events to the contact of the Nazca and South American plate difficult. Nevertheless, in a first stage, their depths may allow possibility of an origin there. * The facilities of the IRIS Data Management System, and specifically the IRIS Data Management Center, were used for access to waveform, metadata or products required in this study. The IRIS DMS is funded through the National Science Foundation and specifically the GEO Directorate through the Instrumentation and Facilities Program of the National Science Foundation under Cooperative Agreement EAR-0552316. Some activities of are supported by the National Science Foundation EarthScope Program under Cooperative Agreement EAR-0733069

  7. Geogebra: Calculation of Centroid

    Qamil Kllogjeri

    2012-09-01

    Full Text Available Our paper is result of the research done in a special direction for solving problems of physics by using GeoGebra programme: calculation of centroid. Lots of simulations of physical phenomena from the class of Mechanics can be performed and computational problems can be solved with GeoGebra. GeoGebra offers many commands and one of them is the command “centroid” to calculate the coordinates of the centroid of a polygon but, we have created a new tool to calculate the coordinates of the centroid of a plane region bounded by curves. Our work is part of the passionate work of many GeoGebra users which will result with a very rich fund of GeoGebra virtual tools, examples and experiences that will be worldwidely available for many teachers and practioners.

  8. Geogebra: Calculation of Centroid

    Qamil Kllogjeri; Pellumb Kllogjeri

    2012-01-01

    Our paper is result of the research done in a special direction for solving problems of physics by using GeoGebra programme: calculation of centroid. Lots of simulations of physical phenomena from the class of Mechanics can be performed and computational problems can be solved with GeoGebra. GeoGebra offers many commands and one of them is the command “centroid” to calculate the coordinates of the centroid of a polygon but, we have created a new tool to calculate the coordinates of the centr...

  9. A Reference Point Construction Method Using Mobile Terminals and the Indoor Localization Evaluation in the Centroid Method

    Takahiro Yamaguchi; Kazumasa Takami

    2015-01-01

    As smartphones become widespread, a variety of smartphone applications are being developed. This paper proposes a method for indoor localization (i.e., positioning) that uses only smartphones, which are general-purpose mobile terminals, as reference point devices. This method has the following features: (a) the localization system is built with smartphones whose movements are confined to respective limited areas. No fixed reference point devices are used; (b) the method does not depend on the...

  10. Research on Centroid Position for Stairs Climbing Stability of Search and Rescue Robot

    Yan Guo

    2011-01-01

    Full Text Available This paper represents the relationship between the stability of stairs climbing and the centroid position of the search and rescue robot. The robot system is considered as a mass point-plane model and the kinematics features are analyzed to find the relationship between centroid position and the maximal pitch angle of stairs the robot could climb up. A computable function about this relationship is given in this paper. During the stairs climbing, there is a maximal stability-keeping angle depends on the centroid position and the pitch angle of stairs, and the numerical formula is developed about the relationship between the maximal stability-keeping angle and the centroid position and pitch angle of stairs. The experiment demonstrates the trustworthy and correction of the method in the paper.

  11. ESTIMATION OF DOPPLER CENTROID FREQUENCY IN SPACEBORNE SCANSAR

    2008-01-01

    Doppler centroid frequency is an essential parameter in the imaging processing of the Scanning mode Synthetic Aperture Radar(ScanSAR).Inaccurate Doppler centroid frequency will result in ghost images in imaging result.In this letter,the principle and algorithms of Doppler centroid frequency estimation are introduced.Then the echo data of ScanSAR system is analyzed.Based on the algorithms of energy balancing and correlation Doppler estimator in the estimation of Doppler centroid fequency in strip mode SAR,an improved method for Doppler centroid frequency estimation in ScanSAR is proposed.The method has improved the accuracy of Doppler centroid fequency estimation in ScanSAR by zero padding between burst data.Finally,the proposed method is validated with the processing of ENVironment SATellite Advanced Synthetic Aperture Radar(ENVISAT ASAR)wide swath raw data.

  12. Weighted Centroid Correction Localization in Cellular Systems

    Rong-Zheng Li

    2011-01-01

    Full Text Available Problem statement: There is a large demand for wireless Location-Based Service (LBS and it is provided by many wireless cellular systems. In process of positioning a Mobile Station (MS, the computing speed is as important as the positioning accuracy and the algorithm should also be resistant to environmental influences. Approach: A new positioning method based on Weighted Centroid Correction Localization (WCCL for wireless cellular systems is introduced in this article. Firstly, referring to the receiving-state of an MS in cellular systems, it computes a weighted centroid of surrounding Base Stations (BSs as a rough approximate position of the MS. Then, according to the distances between the MS and the BSs being less or bigger than the computed distances between the BSs and the weighted centroid, it corrects the coordinate of the weighted centroid towards the directions of the BSs by moving it closer or farther in turn. Results: According to our experiments, WCCL improves the positioning accuracy, as well as to provide a better resistance to environmental influences. Conclusion: As a modified centroid-based localization algorithm, WCCL obtains weighting factors from the receiving-state of MS in multi-cells structured cellular systems and obtains a better positioning result in cellular systems without updating the network equipment. Therefore, for the cellular positioning problem, WCCL algorithm can be an alternate solution.

  13. Centroid Location for Space Targets Based on Multi-step Information Entropy Energy Difference Method%基于多步长最大信息熵的空间目标质心定位

    郭晓军; 徐健; 马新星; 刘峰

    2015-01-01

    The centroid accuracy of star tracker is the base of other accuracies .It's the base of celestial navigation ,star map identification ,orbit positioning and so on ,which is required to reach arc second scale .This paper analyses the main fac‐tors affecting the positioning accuracy of target centroid and the method for star target centroids based on multi‐step maxi‐mum information entropy is proposed .This method uses the linear superposition to narrow the centroid area ,using the sym‐metry of the stellar energy distribution to get the difference at centroid position and obtain the centroid ,then the validation comparison of simulated star images .Experiments show that the positioning accuracy of the method up to 0 .01 pixel ,has good effect to calculate the centroid of low SNR conditions .%高精度星敏感器星点光斑的质心定位精度是星敏感器整体定位精度的基础,是天文导航、星图识别、轨道精确定位等技术的基础,常需要达到角秒级和亚像素的标准。论文分析了影响定位精度的主要因素,并研究了 CCD 观测图像亚像素的高精度质心定位方法,并分析了恒星成像时能量的分布,提出基于多步长最大信息熵的质心定位方法,该方法使用线性叠加缩小质心区域,利用恒星能量分布的对称性,求取信息熵最大时的质心位置,并采用模拟星图验证比较。实验表明,该方法定位精度可达0.01pixel ,对低信噪比条件下的质心计算具有较好的效果。

  14. Micro-pixel accuracy centroid displacement estimation and detector calibration

    Zhai, Chengxing; Goullioud, Renaud; Nemati, Bijan

    2011-01-01

    Precise centroid estimation plays a critical role in accurate astrometry using telescope images. Conventional centroid estimation fits a template point spread function (PSF) to the image data. Because the PSF is typically not known to high accuracy due to wavefront aberrations and uncertainties in optical system, a simple Gaussian function is commonly used. PSF knowledge error leads to systematic errors in the conventional centroid estimation. In this paper, we present an accurate centroid estimation algorithm by reconstructing the PSF from well sampled (above Nyquist frequency) pixelated images. In the limit of an ideal focal plane array whose pixels have identical response function (no inter-pixel variation), this method can estimate centroid displacement between two 32$\\times$32 images to sub-micropixel accuracy. Inter-pixel response variations exist in real detectors, {\\it e.g.}~CCDs, which we can calibrate by measuring the pixel response of each pixel in Fourier space. The Fourier transforms of the inter...

  15. INTEGRATING NAIVE BAYES AND K-MEANS CLUSTERING WITH DIFFERENT INITIAL CENTROID SELECTION METHODS IN THE DIAGNOSIS OF HEART DISEASE PATIENTS

    Mai Shouman; Tim Turner; Rob Stocker

    2012-01-01

    Heart disease is the leading cause of death in the world over the past 10 years. Researchers have been using several data mining techniques to help health care professionals in the diagnosis of heart disease. Naïve Bayes is one of the data mining techniques used in the diagnosis of heart disease showing considerable success. K-means clustering is one of the most popular clustering techniques; however initial centroid selection strongly affects its results. This paper demonstrat...

  16. Variable centroid control scheme over hypersonic tactical missile

    Yl; Yan(易彦); ZHOU; Fengqi(周凤岐)

    2003-01-01

    This paper presents a brand-new tactical missile control scheme--variable centroid vector control according to the international highlight in the field of missile control and the research status of hypersonic missile control in China. Four critical problems related with the new control method are included: improving phase control in the spinning missile single-channel control; establishing variable centroid controlled spinning missile attitude dynamics equations; analyzing variable centroid control strategies and analyzing the stability of the controlled missile and implementing robust control. The achievements and results obtained are valuable and helpful to the theoretical explorations and engineering applications.

  17. An efficient g-centroid location algorithm for cographs

    V. Prakash

    2005-07-01

    Full Text Available In 1998, Pandu Rangan et al. Proved that locating the g-centroid for an arbitrary graph is 𝒩𝒫-hard by reducing the problem of finding the maximum clique size of a graph to the g-centroid location problem. They have also given an efficient polynomial time algorithm for locating the g-centroid for maximal outerplanar graphs, Ptolemaic graphs, and split graphs. In this paper, we present an O(nm time algorithm for locating the g-centroid for cographs, where n is the number of vertices and m is the number of edges of the graph.

  18. 近红外星图质心检测C样条插值法和高斯方法比较%Centroid Detection of Targets on Near Infrared Stellar Map Based on C Spline Method and Gauss Method Comprision

    陆斌; 郭少军; 王铎

    2011-01-01

    可见光CCD拍摄的星空图像中目标点的质心求取已经有了很多种方法,可见光中的恒星质心求取方法在近红外星图中同样适用,常用的方法有Gauss拟合法,矩方法(包括修正矩方法)和寻导法等。介绍了质心求取方法中的Gauss拟合法,分析其优劣性,并以这种方法为基础,根据近红外星图导航的实际情况提出了一种较为实用的方法,并验证比较其精度和可行性。%The centroid of the visible light CCD image targets can be derived by using lots of methods,these algorithms are also suitable for the near infrared stellar map.The common methods are: Gauss fitting method,method of moments,derivative search and so on.The Gauss fitting method is introduced and analyzed its advantages and disadvantages.According to this method,a more practical method is proposed based on the near infrared stellar map navigation,verified and compared its accuracy and feasibility.

  19. FINGERPRINT MATCHING BASED ON PORE CENTROIDS

    S. Malathi

    2011-05-01

    Full Text Available In recent years there has been exponential growth in the use of bio- metrics for user authentication applications. Automated Fingerprint Identification systems have become popular tool in many security and law enforcement applications. Most of these systems rely on minutiae (ridge ending and bifurcation features. With the advancement in sensor technology, high resolution fingerprint images (1000 dpi pro- vide micro level of features (pores that have proven to be useful fea- tures for identification. In this paper, we propose a new strategy for fingerprint matching based on pores by reliably extracting the pore features The extraction of pores is done by Marker Controlled Wa- tershed segmentation method and the centroids of each pore are con- sidered as feature vectors for matching of two fingerprint images. Experimental results shows that the proposed method has better per- formance with lower false rates and higher accuracy.

  20. Systematic error analysis and compensation for high accuracy star centroid estimation of star tracker

    2010-01-01

    Subpixel centroid estimation is the most important star image location method of star tracker. This paper presents a theoretical analysis of the systematic error of subpixel centroid estimation algorithm utilizing frequency domain analysis under the con-sideration of sampling frequency limitation and sampling window limitation. Explicit expression of systematic error of cen-troid estimation is obtained, and the dependence of systematic error on Gaussian width of star image, actual star centroid loca-tion and the number of sampling pixels is derived. A systematic error compensation algorithm for star centroid estimation is proposed based on the result of theoretical analysis. Simulation results show that after compensation, the residual systematic errors of 3-pixel-and 5-pixel-windows’ centroid estimation are less than 2×10-3 pixels and 2×10-4 pixels respectively.

  1. Communication: Relation of centroid molecular dynamics and ring-polymer molecular dynamics to exact quantum dynamics

    We recently obtained a quantum-Boltzmann-conserving classical dynamics by making a single change to the derivation of the “Classical Wigner” approximation. Here, we show that the further approximation of this “Matsubara dynamics” gives rise to two popular heuristic methods for treating quantum Boltzmann time-correlation functions: centroid molecular dynamics (CMD) and ring-polymer molecular dynamics (RPMD). We show that CMD is a mean-field approximation to Matsubara dynamics, obtained by discarding (classical) fluctuations around the centroid, and that RPMD is the result of discarding a term in the Matsubara Liouvillian which shifts the frequencies of these fluctuations. These findings are consistent with previous numerical results and give explicit formulae for the terms that CMD and RPMD leave out

  2. Photon counting imaging and centroiding with an electron-bombarded CCD using single molecule localisation software

    Hirvonen, Liisa M.; Barber, Matthew J.; Suhling, Klaus

    2016-06-01

    Photon event centroiding in photon counting imaging and single-molecule localisation in super-resolution fluorescence microscopy share many traits. Although photon event centroiding has traditionally been performed with simple single-iteration algorithms, we recently reported that iterative fitting algorithms originally developed for single-molecule localisation fluorescence microscopy work very well when applied to centroiding photon events imaged with an MCP-intensified CMOS camera. Here, we have applied these algorithms for centroiding of photon events from an electron-bombarded CCD (EBCCD). We find that centroiding algorithms based on iterative fitting of the photon events yield excellent results and allow fitting of overlapping photon events, a feature not reported before and an important aspect to facilitate an increased count rate and shorter acquisition times.

  3. Finding protein sites using machine learning methods

    Jaime Leonardo Bobadilla Molina

    2010-04-01

    Full Text Available The increasing amount of protein three-dimensional (3D structures determined by x-ray and NMR technologies as well as structures predicted by computational methods results in the need for automated methods to provide inital annotations. We have developed a new method for recognizing sites in three-dimensional protein structures. Our method is based on a previosly reported algorithm for creating descriptions of protein microenviroments using physical and chemical properties at multiple levels of detail. The recognition method takes three inputs: 1. A set of control nonsites that share some structural or functional role. 2. A set of control nonsites that lack this role. 3. A single query site. A support vector machine classifier is built using feature vectors where each component represents a property in a given volume. Validation against an independent test set shows that this recognition approach has high sensitivity and specificity. We also describe the results of scanning four calcium binding proteins (with the calcium removed using a three dimensional grid of probe points at 1.25 angstrom spacing. The system finds the sites in the proteins giving points at or near the blinding sites. Our results show that property based descriptions along with support vector machines can be used for recognizing protein sites in unannotated structures.

  4. Fast tracking mode predictive centroiding scheme

    Rehman, Masood-Ur; Fang, Jiancheng; Saffih, Faycal; Quan, Wei

    2008-10-01

    The autonomous star trackers, using charge couple device CCD camera, or active pixel sensor APS, as natural sensors for optical input, has assumed a permanent position. This is due to their highly accurate attitude determination, small size, light weight and simple functionality, making them devices of choice in nearly all modern space vehicles especially for Nano-satellites. In all star trackers, star centroiding is a fundamental process necessary for pattern recognition. In this paper, a new method is presented, which predicts centers of regions of star locations, in successive image frames, from the current knowledge of boresight direction, which is updated successively. This method is very attractive for hardware implementation using APS imagers known for their random accessibility feature lacked in CCD's. The big advantage of this method is that it does not need pattern recognition, thus making it fast. This reduction of computational budget, power consumption and time, added to the capability of incorporating them in APS imagers, is appealing to Nano-satellites navigational instrumentation.

  5. Determination of Star Bodies from -Centroid Bodies

    Lujun Guo; Gangsong Leng

    2013-11-01

    In this paper, we prove that an origin-symmetric star body is uniquely determined by its -centroid body. Furthermore, using spherical harmonics, we establish a result for non-symmetric star bodies. As an application, we show that there is a unique member of $_p\\langle K \\rangle$ characterized by having larger volume than any other member, for all real ≥ 1 that are not even natural numbers, where $_p\\langle K \\rangle$ denotes the -centroid equivalence class of the star body .

  6. Properties of Planet-induced Deviations in the Astrometric Microlensing Centroid Shift Trajectory

    Han, Cheongho; Lee, Chunguk

    2001-01-01

    In this paper, we investigate the properties of the planet-induced deviations in the trajectory of the microlensed source star centroid motion (astrometric curve) and the correlations between the astrometric and photometric deviations. For this, we construct vector field maps of excess centroid shifts. Fromthe investigation of the maps, we find that the astrometric deviation is closely correlated with the photometric one. The astrometric deviation increases as the photometric deviation increa...

  7. Bayesian methods for finding sparse representations

    Wipf, David Paul

    2006-01-01

    Finding the sparsest or minimum L0-norm representation of a signal given a (possibly) overcomplete dictionary of basis vectors is an important problem in many application domains, including neuroelectromagnetic source localization, compressed sensing, sparse component analysis, feature selection, image restoration/compression, and neural coding. Unfortunately, the required optimization is typically NP-hard, and so approximate procedures that succeed with high probability are sought. Nearly al...

  8. Study on Zero-Doppler Centroid Control for GEO SAR Ground Observation

    2014-01-01

    In geosynchronous Earth orbit SAR (GEO SAR), Doppler centroid compensation is a key step for imaging process, which could be performed by the attitude steering of a satellite platform. However, this zero-Doppler centroid control method does not work well when the look angle of radar is out of an expected range. This paper primarily analyzes the Doppler properties of GEO SAR in the Earth rectangular coordinate. Then, according to the actual conditions of the GEO SAR ground observation, the eff...

  9. Foot Bone in Vivo: Its Center of Mass and Centroid of Shape

    Fan, Yifang; Fan, Yubo; Lin, Zhiyu; Lv, Changsheng

    2010-01-01

    This paper studies foot bone geometrical shape and its mass distribution and establishes an assessment method of bone strength. Using spiral CT scanning, with an accuracy of sub-millimeter, we analyze the data of 384 pieces of foot bones in vivo and investigate the relationship between the bone's external shape and internal structure. This analysis is explored on the bases of the bone's center of mass and its centroid of shape. We observe the phenomenon of superposition of center of mass and centroid of shape fairly precisely, indicating a possible appearance of biomechanical organism. We investigate two aspects of the geometrical shape, (i) distance between compact bone's centroid of shape and that of the bone and (ii) the mean radius of the same density bone issue relative to the bone's centroid of shape. These quantities are used to interpret the influence of different physical exercises imposed on bone strength, thereby contributing to an alternate assessment technique to bone strength.

  10. Numerical Methods for Finding Stationary Gravitational Solutions

    Dias, Oscar J C; Way, Benson

    2015-01-01

    The wide applications of higher dimensional gravity and gauge/gravity duality have fuelled the search for new stationary solutions of the Einstein equation (possibly coupled to matter). In this topical review, we explain the mathematical foundations and give a practical guide for the numerical solution of gravitational boundary value problems. We present these methods by way of example: resolving asymptotically flat black rings, singly-spinning lumpy black holes in anti-de Sitter (AdS), and the Gregory-Laflamme zero modes of small rotating black holes in AdS$_5\\times S^5$. We also include several tools and tricks that have been useful throughout the literature.

  11. Numerical methods for finding stationary gravitational solutions

    Dias, Óscar J. C.; Santos, Jorge E.; Way, Benson

    2016-07-01

    The wide applications of higher dimensional gravity and gauge/gravity duality have fuelled the search for new stationary solutions of the Einstein equation (possibly coupled to matter). In this topical review, we explain the mathematical foundations and give a practical guide for the numerical solution of gravitational boundary value problems. We present these methods by way of example: resolving asymptotically flat black rings, singly spinning lumpy black holes in anti-de Sitter (AdS), and the Gregory–Laflamme zero modes of small rotating black holes in AdS{}5× {S}5. We also include several tools and tricks that have been useful throughout the literature.

  12. Lp-centroid Bo dies and Its Characterizations

    Ma Tong-yi; Zhang De-yan

    2015-01-01

    In this paper, we study the characteristic properties for Lp-centroid bod-ies, and an improved version of Busemann-Petty problem for Lp-centroid bodies is obtained. In addition, using the definitions of Lp-pole curvature image and Lp-affine surface area, a new proof of Busemann-Petty problem for Lp-centroid bodies is given.

  13. Radiographic measures of thoracic kyphosis in osteoporosis: Cobb and vertebral centroid angles

    Briggs, A.M.; Greig, A.M. [University of Melbourne, Centre for Health, Exercise and Sports Medicine, School of Physiotherapy, Victoria (Australia); University of Melbourne, Department of Medicine, Royal Melbourne Hospital, Victoria (Australia); Wrigley, T.V.; Tully, E.A.; Adams, P.E.; Bennell, K.L. [University of Melbourne, Centre for Health, Exercise and Sports Medicine, School of Physiotherapy, Victoria (Australia)

    2007-08-15

    Several measures can quantify thoracic kyphosis from radiographs, yet their suitability for people with osteoporosis remains uncertain. The aim of this study was to examine the validity and reliability of the vertebral centroid and Cobb angles in people with osteoporosis. Lateral radiographs of the thoracic spine were captured in 31 elderly women with osteoporosis. Thoracic kyphosis was measured globally (T1-T12) and regionally (T4-T9) using Cobb and vertebral centroid angles. Multisegmental curvature was also measured by fitting polynomial functions to the thoracic curvature profile. Canonical and Pearson correlations were used to examine correspondence; agreement between measures was examined with linear regression. Moderate to high intra- and inter-rater reliability was achieved (SEM = 0.9-4.0 ). Concurrent validity of the simple measures was established against multisegmental curvature (r = 0.88-0.98). Strong association was observed between the Cobb and centroid angles globally (r = 0.84) and regionally (r = 0.83). Correspondence between measures was moderate for the Cobb method (r = 0.72), yet stronger for the centroid method (r = 0.80). The Cobb angle was 20% greater for regional measures due to the influence of endplate tilt. Regional Cobb and centroid angles are valid and reliable measures of thoracic kyphosis in people with osteoporosis. However, the Cobb angle is biased by endplate tilt, suggesting that the centroid angle is more appropriate for this population. (orig.)

  14. Radiographic measures of thoracic kyphosis in osteoporosis: Cobb and vertebral centroid angles

    Several measures can quantify thoracic kyphosis from radiographs, yet their suitability for people with osteoporosis remains uncertain. The aim of this study was to examine the validity and reliability of the vertebral centroid and Cobb angles in people with osteoporosis. Lateral radiographs of the thoracic spine were captured in 31 elderly women with osteoporosis. Thoracic kyphosis was measured globally (T1-T12) and regionally (T4-T9) using Cobb and vertebral centroid angles. Multisegmental curvature was also measured by fitting polynomial functions to the thoracic curvature profile. Canonical and Pearson correlations were used to examine correspondence; agreement between measures was examined with linear regression. Moderate to high intra- and inter-rater reliability was achieved (SEM = 0.9-4.0 ). Concurrent validity of the simple measures was established against multisegmental curvature (r = 0.88-0.98). Strong association was observed between the Cobb and centroid angles globally (r = 0.84) and regionally (r 0.83). Correspondence between measures was moderate for the Cobb method (r 0.72), yet stronger for the centroid method (r = 0.80). The Cobb angle was 20% greater for regional measures due to the influence of endplate tilt. Regional Cobb and centroid angles are valid and reliable measures of thoracic kyphosis in people with osteoporosis. However, the Cobb angle is biased by endplate tilt, suggesting that the centroid angle is more appropriate for this population. (orig.)

  15. Centroid Velocity Statistics of Molecular Clouds

    Bertram, Erik; Shetty, Rahul; Glover, Simon C O; Klessen, Ralf S

    2014-01-01

    We compute structure functions and Fourier spectra of 2D centroid velocity (CV) maps in order to study the gas dynamics of typical molecular clouds (MCs) in numerical simulations. We account for a simplified treatment of time-dependent chemistry and the non-isothermal nature of the gas and use a 3D radiative transfer tool to model the CO line emission in a post-processing step. We perform simulations using three different initial mean number densities of n_0 = 30, 100 and 300 cm^{-3} to span a range of typical values for dense gas clouds in the solar neighbourhood. We compute slopes of the centroid velocity increment structure functions (CVISF) and of Fourier spectra for different chemical components: the total density, H2 number density, 12CO number density as well as the integrated intensity of 12CO (J=1-0) and 13CO (J=1-0). We show that optical depth effects can significantly affect the slopes derived for the CVISF, which also leads to different scaling properties for the Fourier spectra. The slopes of CVI...

  16. ASTROMETRIC IMAGE CENTROID DISPLACEMENTS DUE TO GRAVITATIONAL MICROLENSING BY THE ELLIS WORMHOLE

    Continuing work initiated in an earlier publication, we study the gravitational microlensing effects of the Ellis wormhole in the weak-field limit. First, we find a suitable coordinate transformation, such that the lens equation and analytic expressions of the lensed image positions can become much simpler. Second, we prove that two images always appear for the weak-field lens by the Ellis wormhole. By using these analytic results, we discuss astrometric image centroid displacements due to gravitational microlensing by the Ellis wormhole. The astrometric image centroid trajectory by the Ellis wormhole is different from the standard one by a spherical lensing object that is expressed by the Schwarzschild metric. The anomalous shift of the image centroid by the Ellis wormhole lens is smaller than that by the Schwarzschild lens, provided that the impact parameter and the Einstein ring radius are the same. Therefore, the lensed image centroid by the Ellis wormhole moves slower. Such a difference, although it is very small, will be, in principle, applicable for detecting or constraining the Ellis wormhole by using future high-precision astrometry observations. In particular, the image centroid position gives us additional information, so that the parameter degeneracy existing in photometric microlensing can be partially broken. The anomalous shift reaches the order of a few micro arcseconds, if our galaxy hosts a wormhole with throat radius larger than 105 km. When the source moves tangentially to the Einstein ring, for instance, the maximum position shift of the image centroid by the Ellis wormhole is 0.18 normalized by the Einstein ring radius. For the same source trajectory, the maximum difference between the centroid displacement by the Ellis wormhole lens and that by the Schwarzschild one with the same Einstein ring radius is -0.16 in the units of the Einstein radius, where the negative means that the astrometric displacement by the Ellis wormhole lens is smaller

  17. Transverse centroid oscillations in solenoidially focused beam transport lattices

    Transverse centroid oscillations are analyzed for a beam in a solenoid transport lattice. Linear equations of motion are derived that describe small-amplitude centroid oscillations induced by displacement and rotational misalignments of the focusing solenoids in the transport lattice, dipole steering elements, and initial centroid offset errors. These equations are analyzed in a local rotating Larmor frame to derive complex-variable 'alignment functions' and 'bending functions' that efficiently describe the characteristics of the centroid oscillations induced by both mechanical misalignments of the solenoids and dipole steering elements. The alignment and bending functions depend only on the properties of the ideal lattice in the absence of errors and steering, and have associated expansion amplitudes set by the misalignments and steering fields, respectively. Applications of this formulation are presented for statistical analysis of centroid oscillations, calculation of actual lattice misalignments from centroid measurements, and optimal beam steering.

  18. Transverse centroid oscillations in solenoidially focused beam transport lattices

    Lund, Steven M.

    2008-01-01

    Linear equations of motion are derived that describe small-amplitude centroid oscillations induced by displacement and rotational misalignments of the focusing solenoids in the transport lattice, dipole steering elements, and initial centroid offset errors. These equations are analyzed in a local rotating Larmor frame to derive complex-variable "alignment functions" and "bending functions" that efficiently describe the characteristics of the centroid oscillations induced by mechanical misalig...

  19. Study of velocity centroids based on the theory of fluctuations in position-position-velocity space

    Kandel, D; Pogosyan, D

    2016-01-01

    We study possibility of obtaining velocity spectra by studying turbulence in an optically thick medium using velocity centroids (VCs).We find that the regime of universal, i.e. independent of underlying turbulence statistics, fluctuations discovered originally within the velocity channel analysis (VCA) carries over to the statistics of VCs. In other words, for large absorptions the VC lose their ability to reflect the spectra of turbulence. Combining our present study with the earlier studies of centroids in Esquivel & Lazarian, we conclude that centroids are applicable for studies subsonic/transsonic turbulence for the range of scales that is limited by the absorption effects. We also consider VCs based on absorption lines and define the range of their applicability. We address the problem of analytical description of spectra and anisotropies of fluctuations that are available through studies using VC. We obtain spectra and anisotropy of VC fluctuations arising from Alfv\\'en, slow and fast modes that con...

  20. A measure of variable planar locations anchored on the centroid of the vowel space

    Watt, Dominic; Fabricius, Anne

    2011-01-01

    This paper presents part of an ongoing research program which aims to apply mathematical and geometrical analytic methods to vowel formant data to enable the quantification of parameters of variation of interest to sociophoneticians. We open with an overview of recent research working towards a set...... of desiderata for choice of normalization algorithm(s) based on replicable procedures. We then present the principles of centroid-based normalization and account for its performance in recent road tests. In sections 4 and 5 we introduce a method that utilizes the centroid of the speaker’s vowel space...

  1. Energy Centroids in the presence of random interactions

    Zhao, Y M; Yoshida, N; Ogawa, K; Yoshinaga, N; Kota, V K B

    2005-01-01

    In this paper we study energy centroids such as those with fixed spin and isospin, those with fixed irreducible representations for bosons, in the presence of random two-body and/or three-body interactions. Our results show that regularities of energy centroids of fixed spin states reported in earlier works are more robust than expected.

  2. Transverse Centroid Oscillations in Solenoidially Focused Beam Transport Lattices

    Lund, S M; Wootton, C J; Lee, E P

    2008-08-01

    Linear equations of motion are derived that describe small-amplitude centroid oscillations induced by displacement and rotational misalignments of the focusing solenoids in the transport lattice, dipole steering elements, and initial centroid offset errors. These equations are analyzed in a local rotating Larmor frame to derive complex-variable 'alignment functions' and 'bending functions' that efficiently describe the characteristics of the centroid oscillations induced by mechanical misalignments of the solenoids and dipole steering elements. The alignment and bending functions depend only on properties of the ideal lattice in the absence of errors and steering and have associated expansion amplitudes set by the misalignments and steering fields. Applications of this formulation are presented for statistical analysis of centroid deviations, calculation of actual lattice misalignments from centroid measurements, and optimal beam steering.

  3. Transverse centroid oscillations in solenoidially focused beam transport lattices

    Lund, Steven M.; Wootton, Christopher J.; Lee, Edward P.

    2008-08-01

    Linear equations of motion are derived that describe small-amplitude centroid oscillations induced by displacement and rotational misalignments of the focusing solenoids in the transport lattice, dipole steering elements, and initial centroid offset errors. These equations are analyzed in a local rotating Larmor frame to derive complex-variable"alignment functions" and"bending functions" that efficiently describe the characteristics of the centroid oscillations induced by mechanical misalignments of the solenoids and dipole steering elements. The alignment and bending functions depend only on properties of the ideal lattice in the absence of errors and steering and have associated expansion amplitudes set by the misalignments and steering fields. Applications of this formulation are presented for statistical analysis of centroid deviations, calculation of actual lattice misalignments from centroid measurements, and optimal beam steering.

  4. Consolidating boundary methods for finding the eigenstates of billiards

    The plane-wave decomposition method, a widely used means of numerically finding eigenstates of the Helmholtz equation in billiard systems is described as a variant of the mathematically well-established boundary integral method (BIM). A new unified framework encompassing the two methods is discussed. Furthermore, a third numerical method, which we call the gauge freedom method is derived from the BIM equations. This opens the way to further improvements in eigenstate search techniques

  5. Improved measurements of RNA structure conservation with generalized centroid estimators

    Yohei eOkada

    2011-08-01

    Full Text Available Identification of non-protein-coding RNAs (ncRNAs in genomes is acrucial task for not only molecular cell biology but alsobioinformatics. Secondary structures of ncRNAs are employed as a keyfeature of ncRNA analysis since biological functions of ncRNAs aredeeply related to their secondary structures. Although the minimumfree energy (MFE structure of an RNA sequence is regarded as the moststable structure, MFE alone could not be an appropriate measure foridentifying ncRNAs since the free energy is heavily biased by thenucleotide composition. Therefore, instead of MFE itself, severalalternative measures for identifying ncRNAs have been proposed such asthe structure conservation index (SCI and the base pair distance(BPD, both of which employ MFE structures. However, thesemeasurements are unfortunately not suitable for identifying ncRNAs insome cases including the genome-wide search and incur high falsediscovery rate. In this study, we propose improved measurements basedon SCI and BPD, applying generalized centroid estimators toincorporate the robustness against low quality multiple alignments.Our experiments show that our proposed methods achieve higher accuracythan the original SCI and BPD for not only human-curated structuralalignments but also low quality alignments produced by CLUSTALW. Furthermore, the centroid-based SCI on CLUSTAL W alignments is moreaccurate than or comparable with that of the original SCI onstructural alignments generated with RAF, a high quality structuralaligner, for which two-fold expensive computational time is requiredon average. We conclude that our methods are more suitable forgenome-wide alignments which are of low quality from the point of viewon secondary structures than the original SCI and BPD.

  6. Iterative method of finding hydraulic conductivity characteristics of soil moisture

    Rysbaiuly, Bolatbek; Adamov, Abilmazhin

    2016-08-01

    The work considers an initial boundary value problem for a nonlinear equation of hydraulic conductivity. A method of finding a nonlinear diffusion coefficient is developed and hydraulic conductivity of soil moisture is found. Numerical calculations are conducted.

  7. A graphical method for finding maximin efficiency designs.

    Imhof, L; Wong, W K

    2000-03-01

    We consider the problem of designing an experiment when there are two competing optimality criteria. Designs that maximize the minimum efficiencies under the two criteria are proposed along with a graphical method for finding these maximin designs. PMID:10783784

  8. Visualization Method for Finding Critical Care Factors in Variance Analysis

    YUI, Shuntaro; BITO, Yoshitaka; OBARA, Kiyohiro; KAMIYAMA, Takuya; SETO, Kumiko; Ban, Hideyuki; HASHIZUME, Akihide; HAGA, Masashi; Oka, Yuji

    2006-01-01

    We present a novel visualization method for finding care factors in variance analysis. The analysis has two stages: first stage enables users to extract a significant variance, and second stage enables users to find out a critical care factors of the variance. The analysis has been validated by using synthetically created inpatient care processes. It was found that the method is efficient in improving clinical pathways.

  9. A centroid model of species distribution with applications to the Carolina wren Thryothorus ludovicianus and house finch Haemorhous mexicanus in the United States

    2016-01-01

    Drastic shifts in species distributions are a cause of concern for ecologists. Such shifts pose great threat to biodiversity especially under unprecedented anthropogenic and natural disturbances. Many studies have documented recent shifts in species distributions. However, most of these studies are limited to regional scales, and do not consider the abundance structure within species ranges. Developing methods to detect systematic changes in species distributions over their full ranges is critical for understanding the impact of changing environments and for successful conservation planning. Here, we demonstrate a centroid model for range-wide analysis of distribution shifts using the North American Breeding Bird Survey. The centroid model is based on a hierarchical Bayesian framework which models population change within physiographic strata while accounting for several factors affecting species detectability. Yearly abundance-weighted range centroids are estimated. As case studies, we derive annual centroids for the Carolina wren and house finch in their ranges in the U.S. We further evaluate the first-difference correlation between species’ centroid movement and changes in winter severity, total population abundance. We also examined associations of change in centroids from sub-ranges. Change in full-range centroid movements of Carolina wren significantly correlate with snow cover days (r = −0.58). For both species, the full-range centroid shifts also have strong correlation with total abundance (r = 0.65, and 0.51 respectively). The movements of the full-range centroids of the two species are correlated strongly (up to r = 0.76) with that of the sub-ranges with more drastic population changes. Our study demonstrates the usefulness of centroids for analyzing distribution changes in a two-dimensional spatial context. Particularly it highlights applications that associate the centroid with factors such as environmental stressors, population characteristics

  10. Monte Carlo Form-Finding Method for Tensegrity Structures

    Li, Yue; Feng, Xi-Qiao; Cao, Yan-Ping

    2010-05-01

    In this paper, we propose a Monte Carlo-based approach to solve tensegrity form-finding problems. It uses a stochastic procedure to find the deterministic equilibrium configuration of a tensegrity structure. The suggested Monte Carlo form-finding (MCFF) method is highly efficient because it does not involve complicated matrix operations and symmetry analysis and it works for arbitrary initial configurations. Both regular and non-regular tensegrity problems of large scale can be solved. Some representative examples are presented to demonstrate the efficiency and accuracy of this versatile method.

  11. Semiclassical approach to centroid splitting of giant resonances on deformed nuclei

    The double-peak splitting of giant resonances on deformed nuclei is investigated microscopically with the semiclassical method. A self-consistent semiclassical approach is employed to determine the nucleon density of deformed nuclei, and the Vlasov equation is utilised to calculate the centroids of giant resonances. The results are in good agreement with experimental ones. (author)

  12. Study on Zero-Doppler Centroid Control for GEO SAR Ground Observation

    Yicheng Jiang

    2014-01-01

    Full Text Available In geosynchronous Earth orbit SAR (GEO SAR, Doppler centroid compensation is a key step for imaging process, which could be performed by the attitude steering of a satellite platform. However, this zero-Doppler centroid control method does not work well when the look angle of radar is out of an expected range. This paper primarily analyzes the Doppler properties of GEO SAR in the Earth rectangular coordinate. Then, according to the actual conditions of the GEO SAR ground observation, the effective range is presented by the minimum and maximum possible look angles which are directly related to the orbital parameters. Based on the vector analysis, a new approach for zero-Doppler centroid control in GEO SAR, performing the attitude steering by a combination of pitch and roll rotation, is put forward. This approach, considering the Earth’s rotation and elliptical orbit effects, can accurately reduce the residual Doppler centroid. All the simulation results verify the correctness of the range of look angle and the proposed steering method.

  13. EPA flow reference method testing and analysis: Findings report. Appendices

    In the summer of 1997, the US Environmental Protection Agency (EPA) conducted a series of week-long field tests at three electric utility sites to evaluate potential improvements to Method 2, EPA's test method for measuring flue gas volumetric flow in stacks. The findings from that study are presented in document EPA/430-R-99-009a (NTIS Order Number PB99-150286). This document contains 10 appendices for that report

  14. Findings

    ... Brain George Hightower searches for genetic mutations that affect HIV's ability to infect the brain. Read Issue All Issues Explore Findings by Topic Cell Biology Cellular Structures, Functions, Processes, Imaging, Stress Response Chemistry and Biochemistry Enzymes, Molecular Probes, Metabolic ...

  15. Doppler Centroid Estimation for Airborne SAR Supported by POS and DEM

    CHENG Chunquan

    2015-05-01

    Full Text Available It is difficult to estimate the Doppler frequency and modulating rate for airborne SAR by using traditional vector method due to instable flight and complex terrain. In this paper, it is qualitatively analyzed that the impacts of POS, DEM and their errors on airborne SAR Doppler parameters. Then an innovative vector method is presented based on the range-coplanarity equation to estimate the Doppler centroid taking the POS and DEM as auxiliary data. The effectiveness of the proposed method is validated and analyzed via the simulation experiments. The theoretical analysis and experimental results show that the method can be used to estimate the Doppler centroid with high accuracy even in the cases of high relief, instable flight, and large squint SAR.

  16. A New Halo Finding Method for N-Body Simulations

    Kim, J; Kim, Juhan; Park, Changbom

    2004-01-01

    We have developed a new halo finding method, Physically Self-Bound (PSB) group finding algorithm, which can efficiently identify halos located even at crowded regions. This method combines two physical criteria such as the tidal radius of a halo and the total energy of each particle to find member particles. Two hierarchical meshes are used to increase the speed and the power of halo identification in the parallel computing environments. First, a coarse mesh with cell size equal to the mean particle separation $l_{\\rm mean}$ is used to obtain the density field over the whole simulation box. Mesh cells having density contrast higher than a local cutoff threshold $\\delta_{\\rm LOC}$ are extracted and linked together for those adjacent to each other. This produces local-cell groups. Second, a finer mesh is used to obtain density field within each local-cell group and to identify halos. If a density shell contains only one density peak, its particles are assigned to the density peak. But in the case of a density s...

  17. An Overview of Methods and Key Findings from the NTDS: The Naturalistic Teenage Driving Study: Methods and Selected Findings

    Simons-Morton, Bruce G.; Klauer, C.; Guo, Feng; Lee, S; Ouimet, Marie-Claude; Albert, P.S.; Dingus, Thomas A.

    2014-01-01

    This paper summarizes the findings on novice teenage driving outcomes (e.g., crashes and risky driving behaviors) from the Naturalistic Teenage Driving Study. Method Survey and driving data from a data acquisition system (global positioning system, accelerometers, cameras) were collected from 42 newly licensed teenage drivers and their parents during the first 18 months of teenage licensure; stress responsivity was also measured in teenagers. Result Overall teenage crash and near-crash (CNC) ...

  18. Outlier Finding from Clusters using Categorical Data

    Anamika Malaiya; Pradeep Chouskey; Gajendra Vaiker

    2012-01-01

    A New Categorical Data algorithm which combines a systematic method for finding initial centroids and an efficient way for assigning data points to clusters. This method ensures the entire process generate cluster without sacrificing the accuracy. It always generate good cluster by reducing the mean square error. Our clustering algorithm serves as a good benchmark to monitor the progression of student’s performance in institute. It also enhances the decision making by academic planners to mon...

  19. A Statistical Study of Beam Centroid Oscillations in a Solenoid Transport Channel

    Lund, S; Wootton, C; Coleman, J; Lidia, S; Seidl, P

    2009-05-07

    A recent theory of transverse centroid oscillations in solenoidally focused beam transport lattices presented in Ref. [1] is applied to statistically analyze properties of the centroid orbit in the Neutralized Drift Compression Experiment (NDCX) at the Lawrence Berkeley National Laboratory. Contributions to the amplitude of the centroid oscillations from mechanical misalignments and initial centroid errors exiting the injector are analyzed. Measured values of the centroid appear consistent with expected alignment tolerances. Correction of these errors is discussed.

  20. Relation of centroid molecular dynamics and ring-polymer molecular dynamics to exact quantum dynamics

    Hele, Timothy J. H.; Willatt, Michael J.; Muolo, Andrea; Althorpe, Stuart C.

    2015-01-01

    We recently obtained a quantum-Boltzmann-conserving classical dynamics by making a single change to the derivation of the `Classical Wigner' approximation. Here, we show that the further approximation of this `Matsubara dynamics' gives rise to two popular heuristic methods for treating quantum Boltzmann time-correlation functions: centroid molecular dynamics (CMD) and ring-polymer molecular dynamics (RPMD). We show that CMD is a mean-field approximation to Matsubara dynamics, obtained by disc...

  1. Bias in the centroid moment tensor for central Asian earthquakes: Evidence from regional surface wave data

    Surface waves recorded on the Chinese Digital Seismic Network (CDSN) station Urumqi (WMQ) are analyzed for 26 centroid moment tensor (CMT) earthquakes located within an epicentral distance of 1300 km. Applying a simple grid search method for source parameter retrieval, I obtain revised estimates of the focal depth, fault strike, and seismic moment (M0) from amplitude spectra of Love and Rayleigh waves and compare these estimates with the CMT best double-couple solutions. The comparisons show that residuals are unbiased for focal depth and fault strike, where population spreads are ±13 km and ±17 degree, respectively. On the other hand, M0 estimates are found to be biased, with CMT M0 larger than regional estimates by an average of 0.27±0.04 log units. The results for focal depth and strike are consistent with previous global and regional studies comparing independent estimates with CMT results. Recent full-waveform modeling studies for central Asian earthquakes support the findings of bias in M0 estimates. I suggest that causes for M0 bias may be related to great thicknesses of continental crust in Hindu Kush and Tien Shan regions and to data censoring practices at small magnitudes. M0:mb scaling relationships for central Asian earthquakes show better agreement with western U.S. scaling when M0 estimates determined in this study are used. copyright 1998 American Geophysical Union

  2. Preliminary results of centroiding experiment for the STEP mission

    Li, Haitao; Li, Baoquan; Cao, Yang; Chen, Ding; Li, Ligang

    2015-08-01

    Search for Terrestrial Exo-Planet (STEP)[1] was originally proposed in 2013 by the National Space Science Center, Chinese Academy of Sciences, which is currently being under background engineering study phase in China. The STEP mission is a space astrometry telescope working at visible light wavelengths. The STEP aims at the nearby terrestrial planets detection through micro-arcsecond-level astrometry. Determination of the separation between star images on a detector with high precision is very important for astrometric exoplanets detection through the observation of star wobbles due to planets. The requirement of centroiding accuracy for STEP is 1e-5 pixel. A centroiding experiment have been carried out on a metrology testbed in open laboratory. In this paper, we present the preliminary results of determining the separations between star images. Without calibration of pixel positions and intra-pixel response, we have demonstrated that the standard deviation of differential centroiding is below 7.4e-3 pixel by the algorithm of linear corrected photon weighted means(LCPWM)[2,3]. For comparison, the photon weighted means(PWM) and Gauss fitting are also used in the data reduction. These results pave the way for the geometrical calibration and the intra-pixel quantum efficiency(QE) calibration of detector array equipment for micro-pixel accuracy centroiding.

  3. Metrology calibration and very high accuracy centroiding with the NEAT testbed

    Crouzier, A; Preis, O; Henault, F; Kern, P; Martin, G; Feautrier, P; Stadler, E; Lafrasse, S; Delboulbe, A; Behar, E; Saint-Pe, M; Dupont, J; Potin, S; Cara, C; Donati, M; Doumayrou, E; Lagage, P O; Léger, A; LeDuigou, J M; Shao, M; Goullioud, R

    2014-01-01

    NEAT is an astrometric mission proposed to ESA with the objectives of detecting Earth-like exoplanets in the habitable zone of nearby solar-type stars. NEAT requires the capability to measure stellar centroids at the precision of 5e-6 pixel. Current state-of-the-art methods for centroid estimation have reached a precision of about 2e-5 pixel at two times Nyquist sampling, this was shown at the JPL by the VESTA experiment. A metrology system was used to calibrate intra and inter pixel quantum efficiency variations in order to correct pixelation errors. The European part of the NEAT consortium is building a testbed in vacuum in order to achieve 5e-6 pixel precision for the centroid estimation. The goal is to provide a proof of concept for the precision requirement of the NEAT spacecraft. The testbed consists of two main sub-systems. The first one produces pseudo stars: a blackbody source is fed into a large core fiber and lights-up a pinhole mask in the object plane, which is imaged by a mirror on the CCD. The ...

  4. Real time quantum dynamics preaveraged over imaginary time path integral: A formal basis for both Centroid Molecular Dynamics and Ring Polymer Molecular Dynamics

    Jang, Seogjoo

    2013-01-01

    An exact real time quantum dynamics preaveraged over imaginary time path integral is formulated for general condensed phase equilibrium ensemble. This formulation results in the well-known centroid dynamics approach upon filtering of centroid constraint, and provides a rigorous framework to understand and analyze a related quantum dynamics approximation method called ring polymer molecular dynamics. The formulation also serves as the basis for developing new kinds of quantum dynamics that uti...

  5. Centroid precision and orientation precision of planar localization microscopy.

    McGray, C; Copeland, C R; Stavis, S M; Geist, J

    2016-09-01

    The concept of localization precision, which is essential to localization microscopy, is formally extended from optical point sources to microscopic rigid bodies. Measurement functions are presented to calculate the planar pose and motion of microscopic rigid bodies from localization microscopy data. Physical lower bounds on the associated uncertainties - termed centroid precision and orientation precision - are derived analytically in terms of the characteristics of the optical measurement system and validated numerically by Monte Carlo simulations. The practical utility of these expressions is demonstrated experimentally by an analysis of the motion of a microelectromechanical goniometer indicated by a sparse constellation of fluorescent nanoparticles. Centroid precision and orientation precision, as developed here, are useful concepts due to the generality of the expressions and the widespread interest in localization microscopy for super-resolution imaging and particle tracking. PMID:26970565

  6. Beam centroid motion estimate for a high current LIA

    A high current linear induction accelerator now is being constructed in Institute of Fluid Physics. It consists of 18 blocks, totally 72 induction accelerating cells, and 18 connection cells with ports for beam diagnostic hardware and vacuum pump. The goal of the facility is to obtain high quality, high current pulse electron beams. In order to reduce corkscrew motion caused by energy spread and misalignment of a focusing system some measures to control the transverse motion of beam centroid must be taken. At first magnetic alignment is performed by using pulsed-wire technique very carefully, then the tilt errors is corrected by a pair of steering coils, which are located inside each cell, after that based on the alignment data a simple estimate of the beam centroid motion has been done by transfer matrix algorithm. In this paper, the calculated and analysis results are presented

  7. Assessing the uncertainties on seismic source parameters: Towards realistic error estimates for centroid-moment-tensor determinations

    Valentine, A.P.; Trampert, J.

    2012-01-01

    The centroid-moment-tensor (CMT) algorithm provides a straightforward, rapid method for the determination of seismic source parameters from waveform data. As such, it has found widespread application, and catalogues of CMT solutions – particularly the catalogue maintained by the Global CMT Project –

  8. A double inequality for bounding Toader mean by the centroidal mean

    Yun Hua; Feng Qi

    2014-11-01

    In this paper, the authors find the best numbers and such that $\\overline{C}( a+ (1 - )b$, $ b + (1 - )a) < T (a, b) < \\overline{C} ( a + (1 - )b, b + (1 - )a)$ for all , > 0 with ≠ , where $\\overline{C}(a, b) = \\frac{2(a^{2}+ab+b^{2})}{3(a+b)}$ and $T(a, b) = \\frac{2}{} \\int^{/2}_{0}\\sqrt{a^{2}\\cos^{2} + b^{2}\\sin^{2} } {\\rm d}$ denote respectively the centroidal mean and Toader mean of two positive numbers and .

  9. The generation of spatial population distributions from census centroid data

    I Bracken; Martin, D.

    1989-01-01

    Census data are commonly used in geographical analysis and to inform planning purposes, though at the disaggregate level the basis of enumeration poses difficulties. In this paper an approach to surface generation is described that offers the prospect of revealing an underlying population distribution from centroid-based data which is independent of zonal geography. It is suggested that this can serve a wide variety of analytical, cartographic, and policy purposes, including the creation of s...

  10. Non-obtuse Remeshing with Centroidal Voronoi Tessellation

    Yan, Dongming

    2015-12-03

    We present a novel remeshing algorithm that avoids triangles with small and triangles with large (obtuse) angles. Our solution is based on an extension to Centroidal Voronoi Tesselation (CVT). We augment the original CVT formulation by a penalty term that penalizes short Voronoi edges, while the CVT term helps to avoid small angles. Our results show significant improvements of the remeshing quality over the state of the art.

  11. Classification of open clusters by centroid method of taxonomical analysis

    Distributions of open clusters of the Galaxy in spaces with coordinates being mass, absolute magnitude, integrated colour index, diameter, metallicity, and age, are considered. Majority of clusters are shown to enter several taxons (classes) with narrow enough limits of these parameters. The classes form a linear sequence by age and two-dimensional sequence on colour - magnitude diagram. They are not isolated but transit into each other continuously. It possibly means an absence of significant gaps in cluster formation process. Bifurcation of age sequence of classes depending on mass and diameter values is found. This allows an evolutionary interpretation

  12. An integrating factor matrix method to find first integrals

    Saputra, K V I [Faculty of Science and Mathematics, University Pelita Harapan, Jl. MH Thamrin Boulevard, Tangerang Banten, 15811 (Indonesia); Quispel, G R W [Department of Mathematics and Statistical Science, La Trobe University, Bundoora 3086 (Australia); Van Veen, L, E-mail: kie.saputra@staff.uph.ed [Faculty of Science, University of Ontario Institute of Technology, 2000 Simcoe St N., Oshawa, Ontario, L1H 7K4 (Canada)

    2010-06-04

    In this paper we develop an integrating factor matrix method to derive conditions for the existence of first integrals. We use this novel method to obtain first integrals, along with the conditions for their existence, for two- and three-dimensional Lotka-Volterra systems with constant terms. The results are compared to previous results obtained by other methods.

  13. An integrating factor matrix method to find first integrals

    Saputra, K V I; van Veen, L

    2010-01-01

    In this paper we developed an integrating factor matrix method to derive conditions for the existence of first integrals. We use this novel method to obtain first integrals, along with the conditions for their existence, for two and three dimensional Lotka-Volterra systems with constant terms. The results are compared to previous results obtained by other methods.

  14. Methods to Find the Number of Latent Skills

    Beheshti, Behzad; Desmarais, Michel C.; Naceur, Rhouma

    2012-01-01

    Identifying the skills that determine the success or failure to exercises and question items is a difficult task. Multiple skills may be involved at various degree of importance, and skills may overlap and correlate. In an effort towards the goal of finding the skills behind a set of items, we investigate two techniques to determine the number of…

  15. Gender-based violence: concepts, methods, and findings.

    Russo, Nancy Felipe; Pirlott, Angela

    2006-11-01

    The United Nations has identified gender-based violence against women as a global health and development issue, and a host of policies, public education, and action programs aimed at reducing gender-based violence have been undertaken around the world. This article highlights new conceptualizations, methodological issues, and selected research findings that can inform such activities. In addition to describing recent research findings that document relationships between gender, power, sexuality, and intimate violence cross-nationally, it identifies cultural factors, including linkages between sex and violence through media images that may increase women's risk for violence, and profiles a host of negative physical, mental, and behavioral health outcomes associated with victimization including unwanted pregnancy and abortion. More research is needed to identify the causes, dynamics, and outcomes of gender-based violence, including media effects, and to articulate how different forms of such violence vary in outcomes depending on cultural context. PMID:17189506

  16. Functional Imaging of Autonomic Regulation: Methods and Key Findings

    Macey, Paul M.; Ogren, Jennifer A.; Kumar, Rajesh; Harper, Ronald M.

    2016-01-01

    Central nervous system processing of autonomic function involves a network of regions throughout the brain which can be visualized and measured with neuroimaging techniques, notably functional magnetic resonance imaging (fMRI). The development of fMRI procedures has both confirmed and extended earlier findings from animal models, and human stroke and lesion studies. Assessments with fMRI can elucidate interactions between different central sites in regulating normal autonomic patterning, and ...

  17. Hough transform method for track finding in center drift chamber

    Azmi, K. A. Mohammad Kamal; Wan Abdullah, W. A. T.; Ibrahim, Zainol Abidin

    2016-01-01

    Hough transform is a global tracking method used which had been expected to be faster approach for tracking the circular pattern of electron moving in Center Drift Chamber (CDC), by transforming the point of hit into a circular curve. This paper present the implementation of hough transform method for the reconstruction of tracks in Center Drift Chamber (CDC) which have been generated by random number in C language programming. Result from implementation of this method shows higher peak of circle parameter value (xc,yc,rc) that indicate the similarity value of the parameter needed for circular track in CDC for charged particles in the region of CDC.

  18. Hough transform method for track finding in center drift chamber

    Azmi, K. A. Mohammad Kamal, E-mail: khasmidatul@siswa.um.edu.my; Wan Abdullah, W. A. T., E-mail: wat@um.edu.my; Ibrahim, Zainol Abidin [National Centre for Particle Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2016-01-22

    Hough transform is a global tracking method used which had been expected to be faster approach for tracking the circular pattern of electron moving in Center Drift Chamber (CDC), by transforming the point of hit into a circular curve. This paper present the implementation of hough transform method for the reconstruction of tracks in Center Drift Chamber (CDC) which have been generated by random number in C language programming. Result from implementation of this method shows higher peak of circle parameter value (xc,yc,rc) that indicate the similarity value of the parameter needed for circular track in CDC for charged particles in the region of CDC.

  19. Hough transform method for track finding in center drift chamber

    Hough transform is a global tracking method used which had been expected to be faster approach for tracking the circular pattern of electron moving in Center Drift Chamber (CDC), by transforming the point of hit into a circular curve. This paper present the implementation of hough transform method for the reconstruction of tracks in Center Drift Chamber (CDC) which have been generated by random number in C language programming. Result from implementation of this method shows higher peak of circle parameter value (xc,yc,rc) that indicate the similarity value of the parameter needed for circular track in CDC for charged particles in the region of CDC

  20. MOBIUS-STRIP-LIKE COLUMNAR FUNCTIONAL CONNECTIONS ARE REVEALED IN SOMATO-SENSORY RECEPTIVE FIELD CENTROIDS.

    James Joseph Wright

    2014-10-01

    Full Text Available Receptive fields of neurons in the forelimb region of areas 3b and 1 of primary somatosensory cortex, in cats and monkeys, were mapped using extracellular recordings obtained sequentially from nearly radial penetrations. Locations of the field centroids indicated the presence of a functional system, in which cortical homotypic representations of the limb surfaces are entwined in three-dimensional Mobius-strip-like patterns of synaptic connections. Boundaries of somatosensory receptive field in nested groups irregularly overlie the centroid order, and are interpreted as arising from the superposition of learned connections upon the embryonic order. Since the theory of embryonic synaptic self-organisation used to model these results was devised and earlier used to explain findings in primary visual cortex, the present findings suggest the theory may be of general application throughout cortex, and may reveal a modular functional synaptic system, which, only in some parts of the cortex, and in some species, is manifest as anatomical ordering into columns.

  1. Improving centroiding by super-resolution reconstruction of sodium layer density in Shack-Hartmann wavefront sensors.

    Mello, Alexandre J T S; Pipa, Daniel R

    2016-05-10

    Adaptive optics in the new generation of large telescopes, over 24 m in diameter, present new challenges. One of them is spot elongation in Shack-Hartmann wavefront sensors when using laser guide stars. The laser brightness depends on the sodium layer density profile, and this is reproduced in the format of an elongated spot. The pattern of the spot is a problem for centroiding techniques, and knowledge of the sodium layer profile is essential for adequate centroiding. In this work, we propose a super-resolution reconstruction technique that combines the information available in various low-resolution elongated spots over the sub-apertures of the sensor to obtain a high-resolution sodium layer density profile that can be used as a reference in centroiding. This is achieved with the information available in the Shack-Hartmann wavefront sensor only, dispensing with external measurements. Finally, we present simulation results of an iterative method that yields a super-resolved sodium layer density profile jointly with improved centroiding. PMID:27168279

  2. Generalized method for finding community structures in networks

    Chang, Chang

    2013-01-01

    To date, most algorithms aiming to find community structures in networks mainly focus on unipartite or bipartite networks. However, to our knowledge, there is no algorithm specifically designed for the mixture network, a third type defined in our paper that represents a wide range of real-world networks. Interestingly, unipartite and bipartite networks can be viewed as limiting cases of a mixture network, suggesting that the mixture network can be considered as a general condition. Based on this observation, we propose a probabilistic model based on the link community model for a unipartite, undirected network [B. Ball, B. Karrer, and M. E. Newman, Phys. Rev. E 84, 036103 (2011)] by redefining this model in the context of a bipartite network and generalizing the bipartite network version model to a mixture network, the general condition, which can be used to find modules in unipartite, bipartite, and mixture networks in a unified framework. We show that both the model of Ball et al. (unipartite, undirected ne...

  3. Class hierarchy method to find Change-Proneness

    Malan V.Gaikwad

    2011-01-01

    Full Text Available Finding Proneness of software is necessary to identify fault prone and change prone classes at earlier stages of development, so that those classes can be given special attention. Also to improves the quality and reliability of the software. For corrective and adaptive maintenance we require to make changes during the software evolution.As such changes cluster around number of key components in software, it is important to analyze the frequency of changes in individual classes and also to identify and show related changes in multiple classes. Early detection of fault prone and change prone classes can enables the developers and experts to spend their valuable time and resources on these areas of software. Prediction of change-prone and fault prone classes of a software is an active topic in the area of software engineering. Such prediction can be used to predict changes to different classes of a system from one release of software to the next release. Identifying the change-prone and fault prone classes in advance can helps to focus attention on these classes.In this paper we are focusing on finding dependency of software that can be chieved by estimating the proneness of Object Oriented Software. Two main types of proneness are associated with OO software. Fault Proneness and Change Proneness.

  4. A Simple Method To Find All Lensed Quasars

    Kochanek, C. S.; Mochejska, B.; Morgan, N. D.; Stanek, K. Z.

    2005-01-01

    We demonstrate that gravitationally lensed quasars are easily recognized using image subtraction methods as time variable sources that are spatially extended. For Galactic latitudes |b|>20 deg, lensed quasars dominate the population of spatially extended variable sources, although there is some contamination from variable star pairs, variable star-quasar pairs and binary quasars that can be easily controlled using other information in the survey such as the object light curves and colors. Thi...

  5. Finding Methods for Innovative Packaging Development: The Card Approach

    Magnusson, Amanda; Olander, Malin; Olsson, Annika

    2013-01-01

    Innovation strategies are crucial for corporate success and should be a top priority for packaging companies. However, to improve the innovativeness of packaging manufacturers, there is a need to increase the integration of product and packaging development and collaboration within the supply chain. New methods for innovative packaging development are needed. Packaging plays a valuable role in the marketing and distribution of products, and can thus add great value for actors in the supply...

  6. Functional Imaging of Autonomic Regulation: Methods and Key Findings

    Paul M Macey

    2016-01-01

    Full Text Available Central nervous system processing of autonomic function involves a network of regions throughout the brain which can be visualized and measured with neuroimaging techniques, notably functional magnetic resonance imaging (fMRI. The development of fMRI procedures has both confirmed and extended earlier findings from animal models, and human stroke and lesion studies. Assessments with fMRI can elucidate interactions between different central sites in regulating normal autonomic patterning, and demonstrate how disturbed systems can interact to produce aberrant regulation during autonomic challenges. Understanding autonomic dysfunction in various illnesses reveals mechanisms that potentially lead to interventions in the impairments. The objectives here are to: 1 describe the fMRI neuroimaging methodology for assessment of autonomic neural control, 2 outline the widespread, lateralized distribution of function in autonomic sites in the normal brain which includes structures from the neocortex through the medulla and cerebellum, 3 illustrate the importance of the time course of neural changes when coordinating responses, and how those patterns are impacted in conditions of sleep-disordered breathing, and 4 highlight opportunities for future research studies with emerging methodologies. Methodological considerations specific to autonomic testing include timing of challenges relative to the underlying fMRI signal, spatial resolution sufficient to identify autonomic brainstem nuclei, blood pressure and blood oxygenation influences on the fMRI signal, and the sustained timing, often measured in minutes of challenge periods and recovery. Key findings include the lateralized nature of autonomic organization, which is reminiscent of asymmetric motor, sensory and language pathways. Testing brain function during autonomic challenges demonstrate closely-integrated timing of responses in connected brain areas during autonomic challenges, and the involvement with

  7. Findings from analysing and quantifying human error using current methods

    In human reliability analysis (HRA), the scarcity of data means that, at best, judgement must be applied to transfer to the domain of the analysis what data are available for similar tasks. In particular for the quantification of tasks involving decisions, the analyst has to choose among quantification approaches that all depend to a significant degree on expert judgement. The use of expert judgement can be made more reliable by eliciting relative judgements rather than absolute judgements. These approaches, which are based on multiple criterion decision theory, focus on ranking the tasks to be analysed by difficulty. While these approaches remedy at least partially the poor performance of experts in the estimation of probabilities, they nevertheless require the calibration of the relative scale on which the actions are ranked in order to obtain the probabilities of interest. This paper presents some results from a comparison of some current HRA methods performed in the frame of a study of SLIM calibration options. The HRA quantification methods THERP, HEART, and INTENT were applied to derive calibration human error probabilities for two groups of operator actions. (author)

  8. A evolutionary method for finding communities in bipartite networks

    WeiHua, Zhan; Jihong, Guan; Shuigeng, Zhou

    2010-01-01

    Common practice in community structure detection is to develop different methods for different classes of networks. Here, we first show that unipartite networks and directed networks can be uniformly represented as bipartite networks, and their modularity completely consist with that for bipartite networks. To optimize the bipartite modularity, we then present a modified adaptive genetic algorithm, called as MMOGA, which is especially suited for community structure detection. In MMOGA, we introduce a new measure for the informativeness of a locus instead of the standard deviation, which can exactly determine those loci to mutate. This measure is the bias between the distribution of a locus over the current population and the uniform distribution of the locus, i.e., Kull-back Divergence between them. Moreover, we develop a reassignment technique for differentiating the informative state a locus has attained from the random state at initial phase. Also we present a modified mutation rule which incorporating rel...

  9. Onychomycosis: Clinical findings, etiological agents and evaluation of laboratory methods

    Dubljanin Eleonora

    2014-01-01

    Full Text Available The aim of this study was to identify the etiological agents in patients with suspected onychomycosis, and to carry out comparative testing of individual or combinations of tests: direct microscopy with KOH and Blankophor (BP, culturing on Sabouraud’s dextrose agar (SDA, diluted Sabouraud’s dextrose agar (D-SDA and dermatophyte test medium (DTM. From 70 nail samples (65 toenails, 5 fingernails, 46 (60.5% had at least one of five positive tests. Isolation was possible in 41, while in 5 samples the presence of fungi was observed by KOH and/or BP. Dermatophytes were most frequently isolated (80.5% where Trichophyton rubrum was predominant. Candida spp. was isolated in 9.8%, Aspergillus spp. 4.9%, Alternaria spp. 2.4% and Fusarium spp. 2.4%. Application of BP as an individual test was the most sensitive method. The combination of BP with DTM or D-SDA provides the best sensitivity and allows the identification of fungi to the species/genus level.

  10. Centroid Moment Tensor Inversion in a 3D heterogeneous Earth: Application to the Australasian region

    Hejrani, B.; Tkalcic, H.; Fichtner, A.

    2015-12-01

    Australia is surrounded by active complex tectonic belts causing significant seismicity. The recent expansion of permanent seismic networks in the Australasian region provides great opportunity to study Earth structure and a great variety of physical mechanisms responsible for earthquakes.On one hand, a better understanding of the Australasian lithosphere, which is now available through tomographic images from full waveform modelling (Fichtner et al. 2010), provides a powerful tool to scrutinize the determination of earthquake source parameters. Even at relatively long periods (40-200s), the 3D effects of regional structure were shown to significantly alter the global centroid moment tensor solutions (Hingee et al. 2012). Thus, we can now explore other types of uncertainties and test the accuracy of global centroid moment tensor (GCMT) solution for the earthquakes in the Australasian region while checking for the systematic inconsistencies in the solutions. This has a significant bearing on tectonic interpretations. For example, azimuth and plunge of fault planes can be investigated in search for systematic biases.On the other hand, the time has come to take a full advantage of the 3D Earth structural model and embrace ongoing advances in computational power and storage. We develop a semi-automated procedure to calculate the Centroid Moment Tensors in a 3D heterogeneous Earth. We utilize the reciprocity theorem to create Green's functions for point sources covering seismogenic zones of Australasia. We focus on improving the capacity of the method to fully complement the existing monitoring tools at Geosciences Australia. Furthermore, we investigate the effects of detailed velocity structure on Centroid location and double-couple percentages. Moreover Azimuth and Plunge of focal mechanisms in GCMT (Global CMT), were investigated in search for any systematic bias.References: Fichtner, A., Kennett, B.L.N., Igel, H., Bunge, H.-P., 2010. Full waveform tomography for

  11. Visualising Pipeline Sensor Datasets with Modified Incremental Orthogonal Centroid Algorithm

    Folorunso Olufemi Ayinde

    2011-09-01

    Full Text Available Each year, millions of people suffer from after-effects of pipeline leakages, spills, and eruptions. Leakages Detection Systems (LDS are often used to understand and analyse these phenomena but unfortunately could not offer complete solution to reducing the scale of the problem. One recent approach was to collect datasets from these pipeline sensors and analyse offline, the approach yielded questionable results due to vast nature of the datasets. These datasets together with the necessity for powerful exploration tools made most pipelines operating companies "data rich but information poor". Researchers have therefore identified problem of dimensional reduction for pipeline sensor datasets as a major research issue. Hence, systematic gap filling data mining development approaches are required to transform data "tombs" into "golden nuggets" of knowledge. This paper proposes an algorithm for this purpose based on the Incremental Orthogonal Centroid (IOC. Search time for specific data patterns may be enhanced using this algorithm.

  12. Regularities with random interactions in energy centroids defined by group symmetries

    Kota, V K B

    2005-01-01

    Regular structures generated by random interactions in energy centroids defined over irreducible representations (irreps) of some of the group symmetries of the interacting boson models $sd$IBM, $sdg$IBM, $sd$IBM-$T$ and $sd$IBM-$ST$ are studied by deriving trace propagations equations for the centroids. It is found that, with random interactions, the lowest and highest group irreps in general carry most of the probability for the corresponding centroids to be lowest in energy. This generalizes the result known earlier, via numerical diagonalization, for the more complicated fixed spin ($J$) centroids where simple trace propagation is not possible.

  13. Time delay and magnification centroid due to gravitational lensing by black holes and naked singularities

    Virbhadra, K S

    2007-01-01

    We model the massive dark object at the center of the Galaxy as a Schwarzschild black hole as well as Janis-Newman-Winicour naked singularities, characterized by the mass and scalar charge parameters, and study gravitational lensing (particularly time delay, magnification centroid, and total magnification) by them. We find that the lensing features are qualitatively similar (though quantitatively different) for the Schwarzschild black holes, weakly naked, and marginally strongly naked singularities. However, the lensing characteristics of strongly naked singularities are qualitatively very different from those due the Schwarzschild black holes. The images produced by Schwarzschild black hole lenses and weakly naked and marginally strongly naked singularity lenses always have positive time delays. On the other hand, the strongly naked singularity lenses can give rise to images with positive, zero, or negative time delays. In particular, for a large angular source position the direct image (the outermost image ...

  14. Outlier Finding from Clusters using Categorical Data

    Anamika Malaiya

    2012-12-01

    Full Text Available A New Categorical Data algorithm which combines a systematic method for finding initial centroids and an efficient way for assigning data points to clusters. This method ensures the entire process generate cluster without sacrificing the accuracy. It always generate good cluster by reducing the mean square error. Our clustering algorithm serves as a good benchmark to monitor the progression of student’s performance in institute. It also enhances the decision making by academic planners to monitor the student’s performance semester by semester by improving on the future academic results in the subsequence academic session.

  15. Total Magnification and Magnification Centroid Due to Strongly Naked Singularity Lensing

    DeAndrea, Justin

    2015-01-01

    A strongly naked singularity (SNS) was modelled at the center of the Galaxy. This specific type of naked singularity was characterized in 2008 by Virbhadra and Keeton. The lens is described using the Janis-Newman-Winicour metric, which has an ordinary mass and massless scalar charge parameters. Gravitational lensing by the SNS gives rise to 4 images: 2 images on the same side as the source and 2 images on the opposite side of the source from the optic axis. We compute magnification centroid, magnification centroid shift, and total absolute magnification for many values of the angular source position. The nature of the curve for all three results are qualitatively similar to Schwarzschild black hole lenses, but quantitatively different. Magnification centroid increases as angular source position increases. As angular source position increases, magnification centroid shift increases to a maximum value, and then begins to decrease. As angular source position becomes large, magnification centroid shift will appro...

  16. Grand-Canonical Adaptive Resolution Centroid Molecular Dynamics: Implementation and Application

    Agarwal, Animesh

    2016-01-01

    We have implemented the Centroid Molecular Dynamics scheme (CMD) into the Grand Canonical-like version of the Adaptive Resolution Simulation Molecular Dynamics (GC-AdResS) method. We have tested the implementation on two different systems, liquid parahydrogen at extreme thermodynamic conditions and liquid water at ambient conditions; the reproduction of structural as well as dynamical results of reference systems are highly satisfactory. The capability of performing GC-AdResS CMD simulations allows for the treatment of a system characterized by some quantum features and open boundaries. This latter characteristic not only is of computational convenience, allowing for equivalent results of much larger and computationally more expensive systems, but also suggests a tool of analysis so far not explored, that is the unambiguous identification of the essential (quantum) degrees of freedom required for a given property.

  17. A Direct Algebraic Method in Finding Particular Solutions to Some Nonlinear Evolution Equations

    LIUChun-Ping; CHENJian-Kang; CAIFan

    2004-01-01

    Firstly, a direct algebraic method and a routine way in finding traveling wave solutions to nonlinear evolution equations are explained. And then some new exact solutions for some evolution equations are obtained by using the method.

  18. High-speed on-chip windowed centroiding using photodiode-based CMOS imager

    Pain, Bedabrata (Inventor); Sun, Chao (Inventor); Yang, Guang (Inventor); Cunningham, Thomas J. (Inventor); Hancock, Bruce (Inventor)

    2004-01-01

    A centroid computation system is disclosed. The system has an imager array, a switching network, computation elements, and a divider circuit. The imager array has columns and rows of pixels. The switching network is adapted to receive pixel signals from the image array. The plurality of computation elements operates to compute inner products for at least x and y centroids. The plurality of computation elements has only passive elements to provide inner products of pixel signals the switching network. The divider circuit is adapted to receive the inner products and compute the x and y centroids.

  19. NEWTON''S METHOD FOR FINDING EXTREMUM OF STRONGLY CONVEX FUNCTIONALS

    BAMADIO B.

    2015-01-01

    Full Text Available In this article the generalized method for solving nonlinear equations for finding the extremum of functions is presented. In the thesis, the examples show that the method of expanding the domain of convergence from different initial approximations, obviously do not meet sufficient conditions for convergence of the classical Newton's method.

  20. Systematic centroid error compensation for the simple Gaussian PSF in an electronic star map simulator

    Wang Haiyong; Wang Yonghai; Li Zhifeng; Song Zhenfei

    2014-01-01

    Simulated star maps serve as convenient inputs for the test of a star sensor, whose stan-dardability mostly depends on the centroid precision of the simulated star image, so it is necessary to accomplish systematic error compensation for the simple Gaussian PSF (or SPSF, in which PSF denotes point spread function). Firstly, the error mechanism of the SPSF is described, the reason of centroid deviations of the simulated star images based on SPSF lies in the unreasonable sampling positions (the centers of the covered pixels) of the Gaussian probability density function. Then in reference to the IPSF simulated star image spots regarded as ideal ones, and by means of normal-ization and numerical fitting, the pixel center offset function expressions are got, so the systematic centroid error compensation can be executed simply by substituting the pixel central position with the offset position in the SPSF. Finally, the centroid precision tests are conducted for the three big error cases of Gaussian radius r=0.5, 0.6, 0.671 pixel, and the centroid accuracy with the compen-sated SPSF (when r=0.5) is improved to 2.83 times that of the primitive SPSF, reaching a 0.008 pixel error, an equivalent level of the IPSF. Besides its simplicity, the compensated SPSF further increases both the shape similarity and the centroid precision of simulated star images, which helps to improve the image quality and the standardability of the outputs of an electronic star map sim-ulator (ESS).

  1. Parallel shooting methods for finding steady state solutions to engine simulation models

    Andersen, Stig Kildegård; Thomsen, Per Grove; Carlsen, Henrik

    2007-01-01

    Parallel single- and multiple shooting methods were tested for finding periodic steady state solutions to a Stirling engine model. The model was used to illustrate features of the methods and possibilities for optimisations. Performance was measured using simulation of an experimental data set as...

  2. Initial data for general relativistic SPH with Centroidal Voronoi Tessellations

    Pablo, Cruz Pérez Juan

    2013-01-01

    In this work we present an alternative method to obtain a distribution of particles over an hyper surface, such that they obey a rest-mass density distribution $\\rho(x^i)$. We use density profiles that can be written as $\\rho(x^1,x^2,x^3)=\\rho(x^1) \\rho(x^2) \\rho(x^3)$ in order to be able to use them as a probability density functions. We can find the relation between the chart $x^j$ and a uniform random variable $\\bar{x}^j \\in (0,1)$, say $F(x^j)=\\bar{x}^j$. Using the inverse of this function we relate a set of $N$ arbitrary number of points inside a cube with coordinates $\\{ x^j =F^{-1}(\\bar{x}^j)\\}$ giving the position in order to get the density distribution $\\rho(x^j)$. We get some noise due to the random distribution and we can notice that each time we relax the configuration on the cube we also get a better distribution of the desired physical configuration described with $\\rho(x^j)$. This relaxation of the position of the particles in the cube has been performed a Lloyd's algorithm in 3D and we have u...

  3. Dressing transformation method for finding soliton solutions of the sinh-Gordon equation

    In this paper, the establishment of the dressing transformations in the sinh-Gordon model is reconsidered. By carefully analysing the infinitesimal structures of dressing transformations, we improve the algebraic method for solving the dressing problem in the system and then lay the dressing transformation method on a firm basis. The modified dressing transformation method, which no longer contains any deductive jumps, turns out to become a powerful Hamiltonian approach to finding N-soliton solutions (N≥1) of the integrable systems. (author)

  4. Very Fast Characterization of Focal Mechanism Parameters Through W-Phase Centroid Inversion in the Context of Tsunami Warning

    Roch, Julien; Duperray, Pierre; Schindelé, François

    2016-03-01

    Most of the tsunami potential seismic sources in the NEAM region are in a magnitude range of 6.5 ≤ Mw ≤ 7.5 (e.g. the tsunami triggered by the Boumerdes earthquake of 2003 with Mw=6.9 ). The CENtre d'ALerte aux Tsunamis (CENALT), in operation since 2012 as the French National Tsunami Warning Centre (NTWC) and Candidate Tsunami Service Provider (CTSP), has to issue warning messages within 15 min of earthquake origin time. These warnings are based on the seismic source parameters (Mw magnitude, focal depth and type of fault), which are computed by focal mechanisms and centroid inversion methods. The W-phase method, developed by Kanamori and Rivera, allows quick computation of seismic source parameters due to the early arrival time between P-waves and surface waves, and is therefore particularly useful for monitoring. We assess the W-phase method with 29 events of magnitude M_w ≥ 5.8 for the period 2010-2015 in the NEAM region. Results with 10 min of signal length are in good agreement compared to the Global Centroid Moment Tensor (GCMT) catalog.

  5. AN EFFICIENT DATA MINING METHOD TO FIND FREQUENT ITEM SETS IN LARGE DATABASE USING TR- FCTM

    Saravanan Suba

    2016-01-01

    Full Text Available Mining association rules in large database is one of most popular data mining techniques for business decision makers. Discovering frequent item set is the core process in association rule mining. Numerous algorithms are available in the literature to find frequent patterns. Apriori and FP-tree are the most common methods for finding frequent items. Apriori finds significant frequent items using candidate generation with more number of data base scans. FP-tree uses two database scans to find significant frequent items without using candidate generation. This proposed TR-FCTM (Transaction Reduction- Frequency Count Table Method discovers significant frequent items by generating full candidates once to form frequency count table with one database scan. Experimental results of TR-FCTM shows that this algorithm outperforms than Apriori and FP-tree.

  6. Accuracy Evaluation for Region Centroid-Based Registration of Fluorescent CLSM Imagery

    Lin Amy

    2006-01-01

    Full Text Available We present an accuracy evaluation of a semiautomatic registration technique for 3D volume reconstruction from fluorescent confocal laser scanning microscope (CLSM imagery. The presented semiautomatic method is designed based on our observations that (a an accurate point selection is much harder than an accurate region (segment selection for a human, (b a centroid selection of any region is less accurate by a human than by a computer, and (c registration based on structural shape of a region rather than based on intensity-defined point is more robust to noise and to morphological deformation of features across stacks. We applied the method to image mosaicking and image alignment registration steps and evaluated its performance with 20 human subjects on CLSM images with stained blood vessels. Our experimental evaluation showed significant benefits of automation for 3D volume reconstruction in terms of achieved accuracy, consistency of results, and performance time. In addition, the results indicate that the differences between registration accuracy obtained by experts and by novices disappear with the proposed semiautomatic registration technique while the absolute registration accuracy increases.

  7. Application of the method of quaternion typification for finding subalgebras and Lie subalgebras of Clifford algebras

    Shirokov, Dmitry

    2009-01-01

    In this paper we further develop the method of quaternion typification of Clifford algebra elements suggested by the author in the previous papers. On the basis of new classification of Clifford algebra elements it is possible to find out and prove a number of new properties of Clifford algebra. In particular, we find subalgebras and Lie subalgebras of Clifford algebra and subalgebras of the Lie algebra of the pseudo-unitary Lie group.

  8. A trilinear method for finding null points in a three-dimensional vector space

    Null points are important locations in vector fields, such as a magnetic field. A new technique (a trilinear method for finding null points) is presented for finding null points over a large grid of points, such as those derived from a numerical experiment. The method was designed so that the null points found would agree with any field lines traced using the commonly used trilinear interpolation. It is split into three parts: reduction, analysis, and positioning, which, when combined, provide an efficient means of locating null points to a user-defined subgrid accuracy. We compare the results of the trilinear method with that of a method based on the Poincare index, and discuss the accuracy and limitations of both methods

  9. The effect of event shape on centroiding in photon counting detectors

    High resolution, CCD readout, photon counting detectors employ simple centroiding algorithms for defining the spatial position of each detected event. The accuracy of centroiding is very dependent upon a number of parameters including the profile, energy and width of the intensified event. In this paper, we provide an analysis of how the characteristics of an intensified event change as the input count rate increases and the consequent effect on centroiding. The changes in these parameters are applied in particular to the MIC photon counting detector developed at UCL for ground and space based astronomical applications. This detector has a maximum format of 3072x2304 pixels permitting its use in the highest resolution applications. Individual events, at light level from 5 to 1000k events/s over the detector area, were analysed. It was found that both the asymmetry and width of event profiles were strongly dependent upon the energy of the intensified event. The variation in profile then affected the centroiding accuracy leading to loss of resolution. These inaccuracies have been quantified for two different 3 CCD pixel centroiding algorithms and one 2 pixel algorithm. The results show that a maximum error of less than 0.05 CCD pixel occurs with the 3 pixel algorithms and 0.1 CCD pixel for the 2 pixel algorithm. An improvement is proposed by utilising straight pore MCPs in the intensifier and a 70 μm air gap in front of the CCD. ((orig.))

  10. A Mixed Method Research for Finding a Model of Administrative Decentralization

    Tahereh Feizy; Alireza Moghali; Masuod Geramipoor; Reza Zare

    2015-01-01

    One of the critical issues of administrative decentralization in translating theory into practice is understanding its meaning. An important method to identify administrative decentralization is to address how it can be planned and implemented, and what are its implications, and how it would overcome challenges. The purpose of this study is finding a model for analyzing and evaluating administrative decentralization, so a mixed method research was used to explore and confirm the model of Admi...

  11. The method of geometric progression for finding a minimum of unimodal functions

    Abdukhamidov, A.U. [Samarkand Univ. (Russian Federation)

    1994-06-05

    An asymptotically optimal method for finding a minimal point x{sup *} for a function f(x) {element_of} C{sup 2}, unimodal on an interval [a{sub k},b{sub k}] is proposed. This method partitions the intervals {delta}{sub k} = b{sub k} - a{sub k}, k = 1, 2, {hor_ellipsis}, and locates x{sup *} by means of a decreasing geometric progression. 1 ref., 1 fig., 2 tabs.

  12. Nudged-elastic band method with two climbing images: finding transition states in complex energy landscapes

    Zarkevich, Nikolai A

    2014-01-01

    The nudged-elastic band (NEB) method is modified with concomitant two climbing images (C2-NEB) to find a transition state (TS) in complex energy landscapes, such as those with serpentine minimal energy path (MEP). If a single climbing image (C1-NEB) successfully finds the TS, C2-NEB finds it with higher stability and accuracy. However, C2-NEB is suitable for more complex cases, where C1-NEB misses the TS because the MEP and NEB directions near the saddle point are different. Generally, C2-NEB not only finds the TS but guarantees that the climbing images approach it from the opposite sides along the MEP, and it estimates accuracy from the three images: the highest-energy one and its climbing neighbors. C2-NEB is suitable for fixed-cell NEB and the generalized solid-state NEB (SS-NEB).

  13. Estimation Normal Vector of Triangular Mesh Vertex by Angle and Centroid Weights and its Application

    Yueping Chen

    2013-04-01

    Full Text Available To compute vertex normal of triangular meshes more accurately, this paper presents an improved algorithm based on angle and centroid weights. Firstly, four representational algorithms are analyzed by comparing their weighting characteristics such as angles, areas and centroids. The drawbacks of each algorithm are discussed. Following that, an improved algorithm is put forward based on angle and centroid weights. Finally, by taking the deviation angle between the nominal normal vector and the estimated one as the error evaluation standard factor, the triangular mesh models of spheres, ellipsoids, paraboloids and cylinders are used to analyze the performance of all these estimation algorithms. The machining and inspection operations of one mould part are conducted to verify the improved algorithm. Experimental results demonstrate that the algorithm is effective.

  14. Systematic centroid error compensation for the simple Gaussian PSF in an electronic star map simulator

    Wang Haiyong

    2014-08-01

    Full Text Available Simulated star maps serve as convenient inputs for the test of a star sensor, whose standardability mostly depends on the centroid precision of the simulated star image, so it is necessary to accomplish systematic error compensation for the simple Gaussian PSF (or SPSF, in which PSF denotes point spread function. Firstly, the error mechanism of the SPSF is described, the reason of centroid deviations of the simulated star images based on SPSF lies in the unreasonable sampling positions (the centers of the covered pixels of the Gaussian probability density function. Then in reference to the IPSF simulated star image spots regarded as ideal ones, and by means of normalization and numerical fitting, the pixel center offset function expressions are got, so the systematic centroid error compensation can be executed simply by substituting the pixel central position with the offset position in the SPSF. Finally, the centroid precision tests are conducted for the three big error cases of Gaussian radius σ = 0.5, 0.6, 0.671 pixel, and the centroid accuracy with the compensated SPSF (when σ = 0.5 is improved to 2.83 times that of the primitive SPSF, reaching a 0.008 pixel error, an equivalent level of the IPSF. Besides its simplicity, the compensated SPSF further increases both the shape similarity and the centroid precision of simulated star images, which helps to improve the image quality and the standardability of the outputs of an electronic star map simulator (ESS.

  15. Fast simulators for satellite cloud optical centroid pressure retrievals; evaluation of OMI cloud retrievals

    J. Joiner

    2012-03-01

    Full Text Available The cloud Optical Centroid Pressure (OCP is a satellite-derived parameter that is commonly used in trace-gas retrievals to account for the effects of clouds on near-infrared through ultraviolet radiance measurements. Fast simulators are desirable to further expand the use of cloud OCP retrievals into the operational and climate communities for applications such as data assimilation and evaluation of cloud vertical structure in general circulation models. In this paper, we develop and validate fast simulators that provide estimates of the cloud OCP given a vertical profile of optical extinction. We use a pressure-weighting scheme where the weights depend upon optical parameters of clouds and/or aerosols. A cloud weighting function is easily extracted using this formulation. We then use fast simulators to compare two different satellite cloud OCP retrievals, from the Ozone Monitoring Instrument (OMI, with estimates based on collocated cloud extinction profiles from a combination of CloudSat radar and MODIS visible radiance data. These comparisons are made over a wide range of conditions to provide a comprehensive validation of the OMI cloud OCP retrievals. We find generally good agreement between OMI cloud OCPs and those predicted by CloudSat. However, the OMI cloud OCPs from the two independent algorithms agree better with each other than either does with the estimates from CloudSat/MODIS. Differences between OMI cloud OCPs and those based on CloudSat/MODIS may result from undetected snow/ice at the surface, cloud 3-D effects, cases of low clouds obscurred by ground-clutter in CloudSat observations and by opaque high clouds in CALIPSO lidar observations, and the fact that CloudSat/CALIPSO only observes a relatively small fraction of an OMI field-of-view.

  16. Fast simulators for satellite cloud optical centroid pressure retrievals, 1. evaluation of OMI cloud retrievals

    J. Joiner

    2011-10-01

    Full Text Available The cloud Optical Centroid Pressure (OCP is a satellite-derived parameter that is commonly used in trace-gas retrievals to account for the effects of clouds on near-infrared through ultraviolet radiance measurements. A fast simulator is desirable in order to further expand the use of cloud OCP retrievals into the operational and climate communities for applications such as data assimilation and evaluation of cloud vertical structure in general circulation models. In this paper, we develop and validate a fast simulator that provides estimates of the cloud OCP given a vertical profile of optical extinction. We use a pressure-weighting scheme where the weights depend upon optical parameters of clouds and/or aerosol. A cloud weighting function is easily extracted using this formulation. We then use the fast simulator to compare two different satellite cloud OCP retrievals from the Ozone Monitoring Instrument (OMI with estimates based on collocated cloud extinction profiles from a combination of CloudSat radar and MODIS visible radiance data. These comparisons are made over a wide range of conditions in order to provide a comprehensive validation of the OMI cloud OCP retrievals. We find generally good agreement between OMI cloud OCPs and those predicted by CloudSat. However, the OMI cloud OCPs from the two independent algorithms agree better with each other than either does with the estimates from CloudSat/MODIS. Differences between OMI cloud OCPs and those based on CloudSat/MODIS may result from undetected snow/ice at the surface, cloud 3-D effects, and the fact that CloudSat only observes a relatively small fraction of OMI pixel.

  17. Fast Simulators for Satellite Cloud Optical Centroid Pressure Retrievals, 1. Evaluation of OMI Cloud Retrievals

    Joiner, J.; Vasilkov, A.; Gupta, P.; Bhartia, P. K.; Veefkind, P.; Sneep, M.; de Haan, J.; Polonsky, I.; Spurr, R.

    2012-01-01

    The cloud Optical Centroid Pressure (OCP), also known as the effective cloud pressure, is a satellite-derived parameter that is commonly used in trace-gas retrievals to account for the effects of clouds on near-infrared through ultraviolet radiance measurements. Fast simulators are desirable to further expand the use of cloud OCP retrievals into the operational and climate communities for applications such as data assimilation and evaluation of cloud vertical structure in general circulation models. In this paper, we develop and validate fast simulators that provide estimates of the cloud OCP given a vertical profile of optical extinction. We use a pressure-weighting scheme where the weights depend upon optical parameters of clouds and/or aerosol. A cloud weighting function is easily extracted using this formulation. We then use fast simulators to compare two different satellite cloud OCP retrievals from the Ozone Monitoring Instrument (OMI) with estimates based on collocated cloud extinction profiles from a combination of CloudS at radar and MODIS visible radiance data. These comparisons are made over a wide range of conditions to provide a comprehensive validation of the OMI cloud OCP retrievals. We find generally good agreement between OMI cloud OCPs and those predicted by CloudSat. However, the OMI cloud OCPs from the two independent algorithms agree better with each other than either does with the estimates from CloudSat/MODIS. Differences between OMI cloud OCPs and those based on CloudSat/MODIS may result from undetected snow/ice at the surface, cloud 3-D effects, low altitude clouds missed by CloudSat, and the fact that CloudSat only observes a relatively small fraction of an OMI field-of-view.

  18. A method for finding the ridge between saddle points applied to rare event rate estimates

    Maronsson, Jon Bergmann; Jónsson, Hannes; Vegge, Tejs

    2012-01-01

    to the path. The method is applied to Al adatom diffusion on the Al(100) surface to find the ridge between 2-, 3- and 4-atom concerted displacements and hop mechanisms. A correction to the harmonic approximation of transition state theory was estimated by direct evaluation of the configuration......A method is presented for finding the ridge between first order saddle points on a multidimensional surface. For atomic scale systems, such saddle points on the energy surface correspond to atomic rearrangement mechanisms. Information about the ridge can be used to test the validity of the harmonic...... approximation to transition state theory, in particular to verify that second order saddle points—maxima along the ridge—are high enough compared to the first order saddle points. New minima along the ridge can also be identified during the path optimisation, thereby revealing additional transition mechanisms...

  19. A Root-MUSIC-Like Direction Finding Method for Cyclostationary Signals

    Yide Wang

    2005-01-01

    Full Text Available We propose a new root-MUSIC-like direction finding algorithm that exploits cyclostationarity in order to improve the direction-of-arrival estimation. The proposed cyclic method is signal selective, it allows to increase the resolution power and the noise robustness significantly, and it is also able to handle more sources than the number of sensors. Computer simulations are used to show the performance of the algorithm.

  20. A Root-MUSIC-Like Direction Finding Method for Cyclostationary Signals

    2005-01-01

    We propose a new root-MUSIC-like direction finding algorithm that exploits cyclostationarity in order to improve the direction-of-arrival estimation. The proposed cyclic method is signal selective, it allows to increase the resolution power and the noise robustness significantly, and it is also able to handle more sources than the number of sensors. Computer simulations are used to show the performance of the algorithm.

  1. Geothermal energy environmental problems and control methods: review of recent findings

    Nguyen, V.T.; Caskey, J.F.; Pfundstein, R.T.; Rifkin, S.B.

    1980-06-01

    The findings of a literature review on the environmental concerns and associated control methods of geothermal energy utilization are presented. The document introduces the environmental problems associated with geothermal energy utilization; assesses the current status of control methods; references appropriate environmental documents; and identifies areas where additional environmental research is needed. The review attempts to consolidate current understanding of the environmental impact of geothermal energy development. Approximately 180 reports written by authors in industry, government and academia have been reviewed in the areas of air emissions, surface and subsurface liquid discharges, solid wastes, noise, subsidence, and induced seismicity.

  2. An Approach for registration method to find corresponding mass lesions in temporal mammogram pairs

    Prof. Samir Kumar Bandyopadhyay

    2010-11-01

    Full Text Available Radiologists generally use multiple mammographic views to detect and characterize suspiciousregions. When radiologists discover a suspicious lesion in one view, they try to find a corresponding lesion in the other views. Views from different projections, typically cranio caudal (CC and medio lateral oblique (MLO views, allow for a better realization of the lesion. Most current computer aided detection (CAD systems differ considerably from radiologists in the way they use multiple views. These systems do not combine information from available views but instead analyse each view separately. Given the positive effect of multiview systems on radiologists' performance we expect that fusion of information from different views will improve CAD systems as well. Such multi-view CAD programs require regional registration methods to find corresponding regions in all available views. In this paper we concentrate on developing such a method for corresponding mass lesions in prior and In other words, starting from a current image containing a mass lesion, the method aims at locating the same mass lesion in the prior image. The method was tested on a set of 412 cancer cases. In each case a malignant mass, architectural distortion or asymmetry was annotated. In 92% of these cases the candidate mass detections by CAD included the cancer regions in both views. It was found that in 82% of the cases a correct link between the true. Positive regions in both views could be established by our method.Key words: Multiple View, Computer-Aided Detection, masses, mammography

  3. Tuberculosis case finding: evaluation of a paper slip method to trace contacts.

    Judith Mwansa-Kambafwile

    Full Text Available SETTING: South Africa has the third highest tuberculosis (TB burden in the world. Intensified case finding, recommended by WHO, is one way to control TB. OBJECTIVE: To evaluate the effectiveness and acceptability of a paper slip method for TB contact tracing. METHOD: TB patients were offered paper slips to give to their contacts, inviting them for TB screening. The number of contacts screened and the proportion diagnosed with TB was calculated. Contacts that returned to the clinic after receiving the slips were interviewed. A focus group discussion (FGD with TB patients was held to determine their acceptability. RESULTS: From 718 paper slips issued, a 26% TB contact tracing rate was found, with a 12% case detection rate. The majority (68% of contacts were screened within 2 weeks of receiving the slip. Age and gender were not significantly associated with time to screening. 16% of the contacts screened did not reside with the TB patients. 98% of the contacts said the method was acceptable. FGD findings show that this method is acceptable and may prevent stigma associated with TB/HIV. CONCLUSION: This simple, inexpensive method yields high contact tracing and case detection rates and potentially would yield additional benefits outside households.

  4. A novel method for finding the initial structure parameters of optical systems via a genetic algorithm

    Jun, LIU; Huang, Wei; Hongjie, Fan

    2016-02-01

    A novel method for finding the initial structure parameters of an optical system via the genetic algorithm (GA) is proposed in this research. Usually, optical designers start their designs from the commonly used structures from a patent database; however, it is time consuming to modify the patented structures to meet the specification. A high-performance design result largely depends on the choice of the starting point. Accordingly, it would be highly desirable to be able to calculate the initial structure parameters automatically. In this paper, a method that combines a genetic algorithm and aberration analysis is used to determine an appropriate initial structure of an optical system. We use a three-mirror system as an example to demonstrate the validity and reliability of this method. On-axis and off-axis telecentric three-mirror systems are obtained based on this method.

  5. Centroid and Theoretical Rotation: Justification for Their Use in Q Methodology Research

    Ramlo, Sue

    2016-01-01

    This manuscript's purpose is to introduce Q as a methodology before providing clarification about the preferred factor analytical choices of centroid and theoretical (hand) rotation. Stephenson, the creator of Q, designated that only these choices allowed for scientific exploration of subjectivity while not violating assumptions associated with…

  6. A general centroid determination methodology, with application to multilayer dielectric structures and thermally stimulated current measurements

    A general methodology is developed to experimentally characterize the spatial distribution of occupied traps in dielectric films on a semiconductor. The effects of parasitics such as leakage, charge transport through more than one interface, and interface trap charge are quantitatively addressed. Charge transport with contributions from multiple charge species is rigorously treated. The methodology is independent of the charge transport mechanism(s), and is directly applicable to multilayer dielectric structures. The centroid capacitance, rather than the centroid itself, is introduced as the fundamental quantity that permits the generic analysis of multilayer structures. In particular, the form of many equations describing stacked dielectric structures becomes independent of the number of layers comprising the stack if they are expressed in terms of the centroid capacitance and/or the flatband voltage. The experimental methodology is illustrated with an application using thermally stimulated current (TSC) measurements. The centroid of changes (via thermal emission) in the amount of trapped charge was determined for two different samples of a triple-layer dielectric structure. A direct consequence of the TSC analyses is the rigorous proof that changes in interface trap charge can contribute, though typically not significantly, to thermally stimulated current

  7. European–Mediterranean Regional Centroid Moment Tensor catalog: Solutions for years 2003 and 2004

    Pondrelli, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia; Salimbeni, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia; Morelli, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia; Ekström, G.; Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, USA; Boschi, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione AC, Roma, Italia

    2007-01-01

    We present an update, for years 2003 and 2004, of the European– Mediterranean Regional Centroid Moment Tensor (RCMT) catalog that we maintain since 1997. This update adds 177 new solutions to the database, relating to moderate-magnitude (4.5 ≤M

  8. Reducing systematic centroid errors induced by fiber optic faceplates in intensified high-accuracy star trackers.

    Xiong, Kun; Jiang, Jie

    2015-01-01

    Compared with traditional star trackers, intensified high-accuracy star trackers equipped with an image intensifier exhibit overwhelmingly superior dynamic performance. However, the multiple-fiber-optic faceplate structure in the image intensifier complicates the optoelectronic detecting system of star trackers and may cause considerable systematic centroid errors and poor attitude accuracy. All the sources of systematic centroid errors related to fiber optic faceplates (FOFPs) throughout the detection process of the optoelectronic system were analyzed. Based on the general expression of the systematic centroid error deduced in the frequency domain and the FOFP modulation transfer function, an accurate expression that described the systematic centroid error of FOFPs was obtained. Furthermore, reduction of the systematic error between the optical lens and the input FOFP of the intensifier, the one among multiple FOFPs and the one between the output FOFP of the intensifier and the imaging chip of the detecting system were discussed. Two important parametric constraints were acquired from the analysis. The correctness of the analysis on the optoelectronic detecting system was demonstrated through simulation and experiment. PMID:26016920

  9. Reducing Systematic Centroid Errors Induced by Fiber Optic Faceplates in Intensified High-Accuracy Star Trackers

    Kun Xiong

    2015-05-01

    Full Text Available Compared with traditional star trackers, intensified high-accuracy star trackers equipped with an image intensifier exhibit overwhelmingly superior dynamic performance. However, the multiple-fiber-optic faceplate structure in the image intensifier complicates the optoelectronic detecting system of star trackers and may cause considerable systematic centroid errors and poor attitude accuracy. All the sources of systematic centroid errors related to fiber optic faceplates (FOFPs throughout the detection process of the optoelectronic system were analyzed. Based on the general expression of the systematic centroid error deduced in the frequency domain and the FOFP modulation transfer function, an accurate expression that described the systematic centroid error of FOFPs was obtained. Furthermore, reduction of the systematic error between the optical lens and the input FOFP of the intensifier, the one among multiple FOFPs and the one between the output FOFP of the intensifier and the imaging chip of the detecting system were discussed. Two important parametric constraints were acquired from the analysis. The correctness of the analysis on the optoelectronic detecting system was demonstrated through simulation and experiment.

  10. A comparison of three clustering methods for finding subgroups in MRI, SMS or clinical data

    Kent, Peter; Jensen, Rikke K; Kongsted, Alice

    2014-01-01

    BACKGROUND: There are various methodological approaches to identifying clinically important subgroups and one method is to identify clusters of characteristics that differentiate people in cross-sectional and/or longitudinal data using Cluster Analysis (CA) or Latent Class Analysis (LCA). There is...... a scarcity of head-to-head comparisons that can inform the choice of which clustering method might be suitable for particular clinical datasets and research questions. Therefore, the aim of this study was to perform a head-to-head comparison of three commonly available methods (SPSS TwoStep CA...... each program's ease of use and interpretability of the presentation of results.We analysed five real datasets of varying complexity in a secondary analysis of data from other research projects. Three datasets contained only MRI findings (n = 2,060 to 20,810 vertebral disc levels), one dataset contained...

  11. Two methods for improving performance of an HMM and their application for gene finding

    Krogh, Anders Stærmose

    1997-01-01

    A hidden Markov model for gene finding consists of submodels for coding regions, splice sites, introns, intergenic regions and possibly more. It is described how to estimate the model as a whole from labeled sequences instead of estimating the individual parts independently from subsequences....... It is argued that the standard maximum likelihood estimation criterion is not optimal for training such a model. Instead of maximizing the probability of the DNA sequence, one should maximize the probability of the correct prediction. Such a criterion, called conditional maximum likelihood, is used...... for the gene finder `HMMgene'. A new (approximative) algorithm is described, which finds the most probable prediction summed over all paths yielding the same prediction. We show that these methods contribute significantly to the high performance of HMMgene....

  12. A New Method for Finding Point Sources in High-energy Neutrino Data

    Fang, Ke; Miller, M. Coleman

    2016-08-01

    The IceCube collaboration has reported the first detection of high-energy astrophysical neutrinos, including ∼50 high-energy starting events, but no individual sources have been identified. It is therefore important to develop the most sensitive and efficient possible algorithms to identify the point sources of these neutrinos. The most popular current method works by exploring a dense grid of possible directions to individual sources, and identifying the single direction with the maximum probability of having produced multiple detected neutrinos. This method has numerous strengths, but it is computationally intensive and because it focuses on the single best location for a point source, additional point sources are not included in the evidence. We propose a new maximum likelihood method that uses the angular separations between all pairs of neutrinos in the data. Unlike existing autocorrelation methods for this type of analysis, which also use angular separations between neutrino pairs, our method incorporates information about the point-spread function and can identify individual point sources. We find that if the angular resolution is a few degrees or better, then this approach reduces both false positive and false negative errors compared to the current method, and is also more computationally efficient up to, potentially, hundreds of thousands of detected neutrinos.

  13. Partly melted DNA conformations obtained with a probability peak finding method

    Tøstesen, Eivind

    2005-06-01

    Peaks in the probabilities of loops or bubbles, helical segments, and unzipping ends in melting DNA are found in this article using a peak finding method that maps the hierarchical structure of certain energy landscapes. The peaks indicate the alternative conformations that coexist in equilibrium and the range of their fluctuations. This yields a representation of the conformational ensemble at a given temperature, which is illustrated in a single diagram called a stitch profile. This article describes the methodology and discusses stitch profiles vs the ordinary probability profiles using the phage lambda genome as an example.

  14. A novel method to find the neutral position of the breast

    Knight, Miranda; Wheat, Jon; Driscoll, Heather; Haake, Steve

    2014-01-01

    Breast pain affects up to 70% of the female population. It is believed that stretching of the breast tissue causes discomfort and that by placing the breast into a position in which the tissue is neither in compression or tension (termed neutral position) will eliminate breast pain. The purpose of the study was to find a simple method that could be used to determine the location of the neutral position. One participant with a breast size of 34C performed three activities. The breast and torso...

  15. Reconciling incongruous qualitative and quantitative findings in mixed methods research: exemplars from research with drug using populations

    Wagner, Karla D.; Davidson, Peter J.; Pollini, Robin A.; Steffanie A Strathdee; Washburn, Rachel; Palinkas, Lawrence A.

    2011-01-01

    Mixed methods research is increasingly being promoted in the health sciences as a way to gain more comprehensive understandings of how social processes and individual behaviours shape human health. Mixed methods research most commonly combines qualitative and quantitative data collection and analysis strategies. Often, integrating findings from multiple methods is assumed to confirm or validate the findings from one method with the findings from another, seeking convergence or agreement betwe...

  16. A new method of finding all Roots of simple quaternionic polynomials

    Feng, Lianggui

    2011-01-01

    In this paper, we provide a new method to find all zeros of polynomials with quaternionic coefficients located on only one side of the powers of the variable (these polynomials are called simple polynomials). This method is much more efficient and much simpler than the known one in [D. Janovska and G. Opfer, A note on the computation of all zeros of simple quaternionic polynomials, SIAM J. Numer. Anal., 48(1)(2010), pp. 244-256]. We recover several known results, and deduce several interesting consequences concerning solving equations with all real coefficients or complex coefficients which do not seem to be deduced easily from the results in [D. Janovska and G. Opfer, A note on the computation of all zeros of simple quaternionic polynomials, SIAM J. Numer. Anal., 48(1)(2010), pp. 244-256]. We also give a necessary and sufficient condition for a simple quaternionic polynomials to have finitely many solutions (only isolated solutions).

  17. Application of Artificial Intelligence methods in Finding Program Comprehension Differences in Novice Object Oriented Programmers

    Marzieh Ahmadzadeh

    2013-09-01

    Full Text Available Program comprehension is the first step required for software maintenance, which accounts for a considerable number of job opportunities. For this to happen, it seems obvious that improving this ability in the teaching environment is required. The literature shows, however, that not enough solutions for improving program comprehension are offered as much as for programming itself.The aim of this research therefore, is to find a pattern of how different students vary in terms of comprehending a code written in an object-oriented language. For this, we have focused on two concepts including inheritance and polymorphism, gathered data online and analyzed it qualitatively. To find the right subject for all the students to study, a data mining technique i.e., the K-means clustering algorithm, was used.Results showed that a slight difference in programming experience can have a significant impact on program comprehension ability. The methods that were used by participants who succeeded in the experiment were the same as methods used by experts as mentioned in earlier research. Inheritance and polymorphism did not play an important role in lack of success in the process of program comprehension.

  18. 4D tumor centroid tracking using orthogonal 2D dynamic MRI: Implications for radiotherapy planning

    Tryggestad, Erik [Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21231 and Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota 55905 (United States); Flammang, Aaron; Shea, Steven M. [Center for Applied Medical Imaging, Siemens Corporation, Corporate Technology, Baltimore, Maryland 21205 (United States); Hales, Russell; Herman, Joseph; Lee, Junghoon; McNutt, Todd; Roland, Teboh; Wong, John [Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21231 (United States)

    2013-09-15

    distribution functions. The surrogate respiratory information allowed the authors to show how this technique can be used to study correlations between internal and external (surrogate) information over these prolonged durations. However, compared against the gold standard of the time stamps in the dMRI frames, the temporal synchronization of the surrogate 1D respiratory information was shown to be likely unreliable.Conclusions: The authors have established viability of a novel and practical pretreatment, 4D tumor centroid tracking method employing a commercially available dynamic MRI sequence. Further developments from the vendor are likely needed to provide a reliably synchronized surrogate 1D respiratory signal, which will likely broaden the utility of this method in the pretreatment radiotherapy planning context.

  19. 4D tumor centroid tracking using orthogonal 2D dynamic MRI: Implications for radiotherapy planning

    distribution functions. The surrogate respiratory information allowed the authors to show how this technique can be used to study correlations between internal and external (surrogate) information over these prolonged durations. However, compared against the gold standard of the time stamps in the dMRI frames, the temporal synchronization of the surrogate 1D respiratory information was shown to be likely unreliable.Conclusions: The authors have established viability of a novel and practical pretreatment, 4D tumor centroid tracking method employing a commercially available dynamic MRI sequence. Further developments from the vendor are likely needed to provide a reliably synchronized surrogate 1D respiratory signal, which will likely broaden the utility of this method in the pretreatment radiotherapy planning context

  20. Exponential tails in the centroid velocity distributions of star-forming regions

    Miesch, M S; Miesch, Mark S; Scalo, John M

    1994-01-01

    Probability density functions (pdfs) of ^{13}CO emission line centroid (line-of-sight, intensity-weighted average) velocities are presented for several densely sampled molecular clouds as quantitative descriptors of their underlying dynamics. Although some are approximately Gaussian in form, most of the pdfs exhibit relatively broader, often nearly exponential, tails, similar to the pdfs of velocity {\\em differences} and {\\em derivatives} (but not the velocity field itself) found in experiments and numerical simulations of incompressible turbulence. The broad pdf tails found in the present work are also similar to those found in decades-old measurements of interstellar velocity pdfs using atomic line centroids, and to the excess wing emission recently found in individual molecular line profiles. Some possible interpretations of the observed deviations are briefly discussed, although none of these account for the nearly exponential tails.

  1. THE USE OF THE PATENT ANALYSIS METHOD FOR FINDING ANALOGUES AND PROTOTYPES OF RECEIVED TECHNICAL SOLUTIONS

    Irina Petrova

    2016-03-01

    Full Text Available The research deals with the issue of the patent analysis efficiency, which is a necessary stage of seaching analogues and prototypes to obtain technical solutions. The article presents the results of analyzing the present automation systems for finding necessary information in the patent databases and identifies their advantages and disadvantages. It gives a description of the “Intellect” system, which is an example of software systems for the conceptual design stage support. Materials and Methods The article presents some of the possible ways to organize the patents-analogues search process and specific features of searching analogues and prototypes for the generated parametric structure scheme of the technical solution, which is the result of the synthesis of a new information-measuring and control system element in the “Intellect” system. The description of the proposed search query forming method is given. The article gives the structure of the patent passport, which must be stored in a database to organize the process of searcing analogues and prototypes. There given a description of algorithms for automatic adding a patent to the database, recalculating the weights while adding a patent by experts, identifying the fact of using different physical and technical effects in a patent. Results The final part of the article contains an example of the results of testing the developed subsystem implementing the proposed method. According to the test results it is concluded that the selected software and algorithmic solutions are effective.

  2. Study of finding out uranium deposit with geophysical methods at Zhongdong district Onyuan county Guangdong province

    The soil natural thermoluminescence measurement and radon survey were chosen, whose penetrability is stronger, and their applied effects were studied in prospecting uranium deposit at Xiazhuang granite area. The 236 stations were measured respectively with these two methods at Zhongdong district Ongyuan county Guangdong province. The research results show that: 1. There are good effects which fractured zones were found out with radon survey. 2. The soil natural thermoluminescence measurement is one of the cumulative measurement methods. It can obviously respond the projected position of uranium deposit of intersected point type. 3. The sensitivity, stability and reappearance of the soil natural thermoluminescence is good, and it was less affected by human activity on the surface. The measured anomalies can reflect the variety of the radioactive field, so amplitude and width of anomalies can basically respond the distribution of uranium ore body. The problems to be solved in the future are: If the rocks above the 'intersection point type' uranium deposits are relatively intact, how much depth can it be found out with soil natural thermoluminescence method? A set of nuclear geophysical prospecting pattern on the different types of uranium deposits in Xiazhuang uranium ore field should be summarized so that they can be used to find out uranium deposits in granite area in the future. (authors)

  3. A Bayesian Method For Finding Galaxies That Cause Quasar Absorption Lines

    Shoemaker, Emileigh Suzanne; Laubner, David Andrew; Scott, Jennifer E.

    2016-01-01

    We present a study of candidate absorber-galaxy pairs for 39 low redshift quasar sightlines (0.06 Digital Sky Survey (SDSS). We downloaded the COS linelists for these quasar spectra from MAST and queried the SDSS DR12 database for photometric data on all galaxies within 1 Mpc of each of these quasar lines of sight. We calculated photometric redshifts for all the SDSS galaxies using the Bayesian Photometric Redshift code. We used all these absorber and galaxy data as input into an absorber-galaxy matching code which also employs a Bayesian scheme, along with known statistics of the intergalactic medium and circumgalactic media of galaxies, for finding the most probable galaxy match for each absorber. We compare our candidate absorber-galaxy matches to existing studies in the literature and explore trends in the absorber and galaxy properties among the matched and non-matched populations. This method of matching absorbers and galaxies can be used to find targets for follow up spectroscopic studies.

  4. A method for automatic matching of multi-timepoint findings for enhanced clinical workflow

    Raghupathi, Laks; Dinesh, MS; Devarakota, Pandu R.; Valadez, Gerardo Hermosillo; Wolf, Matthias

    2013-03-01

    Non-interventional diagnostics (CT or MR) enables early identification of diseases like cancer. Often, lesion growth assessment done during follow-up is used to distinguish between benign and malignant ones. Thus correspondences need to be found for lesions localized at each time point. Manually matching the radiological findings can be time consuming as well as tedious due to possible differences in orientation and position between scans. Also, the complicated nature of the disease makes the physicians to rely on multiple modalities (PETCT, PET-MR) where it is even more challenging. Here, we propose an automatic feature-based matching that is robust to change in organ volume, subpar or no registration that can be done with very less computations. Traditional matching methods rely mostly on accurate image registration and applying the resulting deformation map on the findings coordinates. This has disadvantages when accurate registration is time-consuming or may not be possible due to vast organ volume differences between scans. Our novel matching proposes supervised learning by taking advantage of the underlying CAD features that are already present and considering the matching as a classification problem. In addition, the matching can be done extremely fast and at reasonable accuracy even when the image registration fails for some reason. Experimental results∗ on real-world multi-time point thoracic CT data showed an accuracy of above 90% with negligible false positives on a variety of registration scenarios.

  5. MVClustViz: A Novice Yet Simple Multivariate Cluster Visualization Technique for Centroid-based Clusters

    Sagar S. De; Minati Mishra; Satchidananda Dehuri

    2013-01-01

    In the visual data mining, visualization of clusters is a challenging task. Although lots of techniques already have been developed, the challenges still remain to represent large volume of data with multiple dimension and overlapped clusters. In this paper, a multivariate clusters visualization technique (MVClustViz) has been presented to visualize the centroid-based clusters. The geographic projection technique supports multi-dimension, large volume, and both crisp and fuzzy clusters visual...

  6. An Improved Particle Swarm Optimization Algorithm Based on Centroid and Exponential Inertia Weight

    2014-01-01

    Particle swarm optimization algorithm (PSO) is a global stochastic tool, which has ability to search the global optima. However, PSO algorithm is easily trapped into local optima with low accuracy in convergence. In this paper, in order to overcome the shortcoming of PSO algorithm, an improved particle swarm optimization algorithm (IPSO), based on two forms of exponential inertia weight and two types of centroids, is proposed. By means of comparing the optimization ability of IPSO algorithm w...

  7. A Centroid-based Heuristic Algorithm for the Capacitated Vehicle Routing Problem

    Kwangcheol Shin; Sangyong Han

    2012-01-01

    The vehicle routing problem (VRP) is famous as a nondeterministic polynomial-time hard problem. This study proposes a centroid-based heuristic algorithm to solve the capacitated VRP in polynomial time. The proposed algorithm consists of three phases: cluster construction, cluster adjustment, and route establishment. At the cluster construction phase, the farthest node (customer) among un-clustered nodes is selected as a seed to form a cluster. The notion of the geometrical centre of a cluster...

  8. School Locations and Traffic Emissions — Environmental (InJustice Findings Using a New Screening Method

    Philine Gaffron

    2015-02-01

    Full Text Available It has been shown that the location of schools near heavily trafficked roads can have detrimental effects on the health of children attending those schools. It is therefore desirable to screen both existing school locations and potential new school sites to assess either the need for remedial measures or suitability for the intended use. Current screening tools and public guidance on school siting are either too coarse in their spatial resolution for assessing individual sites or are highly resource intensive in their execution (e.g., through dispersion modeling. We propose a new method to help bridge the gap between these two approaches. Using this method, we also examine the public K-12 schools in the Sacramento Area Council of Governments Region, California (USA from an environmental justice perspective. We find that PM2.5 emissions from road traffic affecting a school site are significantly positively correlated with the following metrics: percent share of Black, Hispanic and multi-ethnic students, percent share of students eligible for subsidized meals. The emissions metric correlates negatively with the schools’ Academic Performance Index, the share of White students and average parental education levels. Our PM2.5 metric also correlates with the traffic related, census tract level screening indicators from the California Communities Environmental Health Screening Tool and the tool’s tract level rate of asthma related emergency department visits.

  9. Old Wine in New Skins: The Sensitivity of Established Findings to New Methods

    Foster, E. Michael; Wiley-Exley, Elizabeth; Bickman, Leonard

    2009-01-01

    Findings from an evaluation of a model system for delivering mental health services to youth were reassessed to determine the robustness of key findings to the use of methodologies unavailable to the original analysts. These analyses address a key concern about earlier findings--that the quasi-experimental design involved the comparison of two…

  10. Criteria to find qualified candidates--professional personnel recruitment methods adapted to neurosurgery.

    Gilsbach, J M; Pillong, A

    1997-01-01

    A neurosurgeon has not received any special training in personnel recruitment at the time he becomes chief of a department. Consequently, a suboptimal personnel policy is most probable. Due to the rapid changes in social behaviour and style of leadership in postwar Europe, he might be ill advised to follow only the example of his successful predecessors, apart from the fact, that this would only be possible if the personalities (of the former and new chief) were similar. To save time and energy for optimal patient care, personnel recruitment can be improved and made more reproducible and reliable by adopting modern, professional non-medical principles. A typical stepwise process of personnel recruitment includes an analysis of the position and function, the definition of demands and offers, the choice of advertising and searching methods, the analysis of the application documents, the interview with the candidate including its re-evaluation and the ongoing evaluation process during the training. This election process is not only conducted by the chief of a department, but also by senior staff-members and even young, competing assistants. It aims to find the candidate who fits best in the requirements, who will be trained and educated with the least effort and who has the best potential to succeed in the long run. The only factors seemingly predicting a good development of a candidate are personality, energy (potential, motivation) and intelligence. Therefore, the search should especially aim to discover these-admittedly difficult to detect-qualities. PMID:9253431

  11. Findings from a mixed-methods study of an interprofessional faculty development program.

    Abu-Rish Blakeney, Erin; Pfeifle, Andrea; Jones, Mandy; Hall, Leslie Walter; K Zierler, Brenda

    2016-01-01

    Forty faculty members from eight schools participated in a year-long National Faculty Development Program (NFDP) conducted in 2012-2013, aimed at developing faculty knowledge and skills for interprofessional education (IPE). The NFDP included two live conferences. Between conferences, faculty teams implemented self-selected IPE projects at their home institutions and participated in coaching and peer-support conference calls. This paper describes program outcomes. A mixed methods approach was adopted. Data were gathered through online surveys and semi-structured interviews. The study explored whether faculty were satisfied with the program, believed the program was effective in developing knowledge and skills in designing, implementing, and evaluating IPE, and planned to continue newly-implemented IPE and faculty development (FD). Peer support and networking were two of the greatest perceived benefits. Further, this multi-institutional program appears to have facilitated early organizational change by bringing greater contextual understanding to assumptions made at the local level that in turn could influence hidden curricula and networking. These findings may guide program planning for future FD to support IPE. PMID:26576839

  12. Transition state-finding strategies for use with the growing string method

    Goodrow, Anthony; Bell, Alexis T.; Head-Gordon, Martin

    2009-06-01

    Efficient identification of transition states is important for understanding reaction mechanisms. Most transition state search algorithms require long computational times and a good estimate of the transition state structure in order to converge, particularly for complex reaction systems. The growing string method (GSM) [B. Peters et al., J. Chem. Phys. 120, 7877 (2004)] does not require an initial guess of the transition state; however, the calculation is still computationally intensive due to repeated calls to the quantum mechanics code. Recent modifications to the GSM [A. Goodrow et al., J. Chem. Phys. 129, 174109 (2008)] have reduced the total computational time for converging to a transition state by a factor of 2 to 3. In this work, three transition state-finding strategies have been developed to complement the speedup of the modified-GSM: (1) a hybrid strategy, (2) an energy-weighted strategy, and (3) a substring strategy. The hybrid strategy initiates the string calculation at a low level of theory (HF/STO-3G), which is then refined at a higher level of theory (B3LYP/6-31G∗). The energy-weighted strategy spaces points along the reaction pathway based on the energy at those points, leading to a higher density of points where the energy is highest and finer resolution of the transition state. The substring strategy is similar to the hybrid strategy, but only a portion of the low-level string is refined using a higher level of theory. These three strategies have been used with the modified-GSM and are compared in three reactions: alanine dipeptide isomerization, H-abstraction in methanol oxidation on VOx/SiO2 catalysts, and C-H bond activation in the oxidative carbonylation of toluene to p-toluic acid on Rh(CO)2(TFA)3 catalysts. In each of these examples, the substring strategy was proved most effective by obtaining a better estimate of the transition state structure and reducing the total computational time by a factor of 2 to 3 compared to the modified

  13. Infant feeding experiences among teen mothers in North Carolina: Findings from a mixed-methods study

    Samandari Ghazaleh

    2011-09-01

    Full Text Available Abstract Background Adolescent mothers in the U.S. are much less likely to initiate breastfeeding than older mothers, and teens who do initiate breastfeeding tend to breastfeed for shorter durations. The purpose of this mixed-methods study is to investigate breastfeeding practices, barriers and facilitators among adolescent mothers ages 17 and younger. Methods Quantitative descriptive analyses are conducted using data from the North Carolina Pregnancy Risk Assessment Monitoring System (PRAMS. The population-based sample comprises 389 teens ages 13-17 giving birth to a live born infant in North Carolina in 2000 - 2005 and in 2007. Qualitative analyses are based on in-depth interviews with 22 Black, White and Hispanic teen mothers residing in rural and urban areas of North Carolina conducted between November 2007 and February 2009. Results In quantitative analyses, 52% (196 of 389 of North Carolina teen mothers initiated breastfeeding, but half of those who initiated breastfeeding (92/196 stopped within the first month postpartum. Hispanic teens (44/52 or 89% were much more likely than Black (61/159 or 41% or White teens (87/164 or 52% to initiate breastfeeding and to continue for a longer duration. Nearly sixty two percent (29/52 of Hispanic respondents breastfed for greater than four weeks as compared to 16% (29/159 of Black respondents and 26% (39/164 of White respondents. Common barriers to breastfeeding initiation and continuation included not liking breastfeeding, returning to school, nipple pain, and insufficient milk. Qualitative data provided context for the quantitative findings, elucidating the barriers and facilitators to breastfeeding from the teens' perspective and insight into the ways in which breastfeeding support to teens could be enhanced. Conclusions The large number of adolescents ceasing breastfeeding within the first month points to the need for more individualized follow-up after hospital discharge in the first few days

  14. Centers and centroids of the cone-beam projection of a ball.

    Clackdoyle, R; Mennessier, C

    2011-12-01

    In geometric calibration of cone-beam (CB) scanners, point-like marker objects such as small balls are imaged to obtain positioning information from which the unknown geometric parameters are extracted. The procedure is sensitive to errors in the positioning information, and one source of error is a small bias which can occur in estimating the detector locations of the CB projections of the centers of the balls. We call these detector locations the center projections. In general, the CB projection of a ball of uniform density onto a flat detector forms an ellipse. Inside the ellipse lie the center projection M, the ellipse center C and the centroid G of the intensity values inside the ellipse. The center projection is invariably estimated from C or G which are much easier to extract directly from the data. In this work, we quantify the errors incurred in using C or G to estimate M. We prove mathematically that the points C, G, M and O are always distinct and lie on the major axis of the ellipse, where O is the detector origin, defined as the orthogonal projection of the cone vertex onto the detector. (The ellipse can only degenerate to a circle if the ball is along the direct line of sight to O, and in this case all four points coincide.) The points always lie in the same order: O, M, G, C which establishes that the centroid has less geometric bias than the ellipse center for estimating M. However, our numerical studies indicate that the centroid bias is only 20% less than the ellipse center bias so the benefit in using centroid estimates is not substantial. For the purposes of quantifying the bias in practice, we show that the ellipse center bias ||CM|| can be conveniently estimated by eA/(π ƒ(≈) where A is the area of the elliptical projection, e is the eccentricity of the ellipse and ƒ(≈) is an estimate of the focal length of the system. Finally, we discuss how these results are affected by physical factors such as beam hardening, and indicate extensions

  15. Centers and centroids of the cone-beam projection of a ball

    In geometric calibration of cone-beam (CB) scanners, point-like marker objects such as small balls are imaged to obtain positioning information from which the unknown geometric parameters are extracted. The procedure is sensitive to errors in the positioning information, and one source of error is a small bias which can occur in estimating the detector locations of the CB projections of the centers of the balls. We call these detector locations the center projections. In general, the CB projection of a ball of uniform density onto a flat detector forms an ellipse. Inside the ellipse lie the center projection M, the ellipse center C and the centroid G of the intensity values inside the ellipse. The center projection is invariably estimated from C or G which are much easier to extract directly from the data. In this work, we quantify the errors incurred in using C or G to estimate M. We prove mathematically that the points C, G, M and O are always distinct and lie on the major axis of the ellipse, where O is the detector origin, defined as the orthogonal projection of the cone vertex onto the detector. (The ellipse can only degenerate to a circle if the ball is along the direct line of sight to O, and in this case all four points coincide.) The points always lie in the same order: O, M, G, C which establishes that the centroid has less geometric bias than the ellipse center for estimating M. However, our numerical studies indicate that the centroid bias is only 20% less than the ellipse center bias so the benefit in using centroid estimates is not substantial. For the purposes of quantifying the bias in practice, we show that the ellipse center bias ||CM|| can be conveniently estimated by eA/(π f-tilde) where A is the area of the elliptical projection, e is the eccentricity of the ellipse and f-tilde is an estimate of the focal length of the system. Finally, we discuss how these results are affected by physical factors such as beam hardening, and indicate extensions

  16. European Mediterranean Regional Centroid Moment Tensor catalog: Solutions for years 2003 and 2004

    Pondrelli, S.; Salimbeni, S.; Morelli, A.; Ekström, G.; Boschi, E.

    2007-09-01

    We present an update, for years 2003 and 2004, of the European- Mediterranean Regional Centroid Moment Tensor (RCMT) catalog that we maintain since 1997. This update adds 177 new solutions to the database, relating to moderate-magnitude ( 4.5≤MBoumerdes, Algerian coast in 2003 and Al Hoceima, Morocco in 2004) and in Southern Greece and Dodecanese region (August 2003 and 2004). The complete RCMT catalog for the European and Mediterranean region now covers 8 years, and contains about 600 solutions.

  17. Determination of the beam centroid of an obstructed focused Gaussian laser beam.

    St John, W Doyle

    2009-08-01

    Diffraction of an obstructed focused Gaussian laser beam has been treated theoretically using the Huygens-Fresnel diffraction integral and was found to be in good agreement with experimental measurements. The obstruction is a vertically oriented opaque cylinder treated as a flat hard aperture. Measurements and calculations are compared for the diffracted irradiance profile and the beam centroid as a function of cylinder diameter and lateral and longitudinal placement along the optic axis. The cylinders used were gauge pins and/or wires with diameters from 0.5 to 100 mil. PMID:19649057

  18. Determination of the beam centroid of an obstructed focused Gaussian laser beam

    Diffraction of an obstructed focused Gaussian laser beam has been treated theoretically using the Huygens-Fresnel diffraction integral and was found to be in good agreement with experimental measurements. The obstruction is a vertically oriented opaque cylinder treated as a flat hard aperture. Measurements and calculations are compared for the diffracted irradiance profile and the beam centroid as a function of cylinder diameter and lateral and longitudinal placement along the optic axis. The cylinders used were gauge pins and/or wires with diameters from 0.5 to 100 mil.

  19. Determination of the beam centroid of an obstructed focused Gaussian laser beam

    Doyle St John, W.

    2009-08-01

    Diffraction of an obstructed focused Gaussian laser beam has been treated theoretically using the Huygens-Fresnel diffraction integral and was found to be in good agreement with experimental measurements. The obstruction is a vertically oriented opaque cylinder treated as a flat hard aperture. Measurements and calculations are compared for the diffracted irradiance profile and the beam centroid as a function of cylinder diameter and lateral and longitudinal placement along the optic axis. The cylinders used were gauge pins and/or wires with diameters from 0.5 to 100 mil.

  20. 一种双臂巡检机器人的质心调整策略%Centroid adjustment strategy for a dual arm inspection robot

    李贞辉; 王洪光; 王越超

    2014-01-01

    In this paper, a centroid adjustment strategy is presented for solving the dynamic stability problem for a du⁃al arm inspection robot when it is hung by single arm. Based on analysis of the obstacle crossing process of the robot, a kinetic model is established when the robot is hung by a single arm and a state⁃feedback controller based on the ro⁃bot model is presented. This paper also discusses the planning method for the variable of joints based on shortest tran⁃sition time, achieving the dynamically stable movement by regulating joint variables in time and adjusting the centroid of the robot. The simulation and experimental results showed that the centroid adjustment strategy is feasible.%针对一种双臂巡检机器人单臂挂线越障时的动态稳定问题,提出了一种质心调整策略。在分析机器人越障过程的基础上,建立了机器人单臂挂线时的动力学模型,设计了一种状态反馈控制器。提出以过渡时间最短为目标规划关节变量,设定机器人倾角和两臂间距为控制目标,实时调节各关节运动,通过控制调整机器人质心位置实现机器人越障时的稳定运动。仿真和实验证明了所提质心调整策略的可行性。

  1. Update of the European-Mediterranean Regional Centroid Moment Tensor (RCMT) Catalog: an Insight on Notable Recent Mediterranean Seismicity

    Pondrelli, S.; Salimbeni, S.; Ekström, G.; Morelli, A.

    2006-12-01

    The European-Mediterranean Regional Centroid Moment Tensor (RCMT) Catalog collects solutions routinely computed since 1997 for earthquakes with moderate magnitude (4.5≤ M ≤ 5.5) in the Mediterranean region. The database represents an extension to smaller magnitudes of the Harvard global CMT catalog, based on analysis of seismograms recorded at regional distance, and modeling of intermediate period surface waves. The catalog, updated to 2005, includes about 650 events, and represents a valuable tool for seismotectonic and geodynamic studies. The most interesting seismic sequences in the most recent years occurred in Northern Africa (Boumerdes, Algerian coast in 2003 and Al Hoceima, Morocco in 2004) and in the Southern Greece, Dodecanese area and Aegean Sea (August 2003 and 2004, October 2005). For most of the events of these sequences moment tensor solutions were not available in the literature. We further extended the catalog back in time for the Italian region, as far as allowed by availability of digital data --- i.e. since 1977 --- with the same analysis and inversion method used for current seismicity. The new dataset includes events in many seismic zones where moderate seismicity had previously been scarcely documented, e.g. the Po Plain and the Adriatic Sea. In particular, both older and more recent seismicity in the Central Adriatic Sea holds particular interest, as the region had often been depicted as aseismic. New solutions, providing new information on the geometry of seismic deformation, mainly represent moderate magnitude events, that can effectively be modeled by the method we use.

  2. Target Centroid Position Estimation of Phase-Path Volume Kalman Filtering

    Fengjun Hu

    2016-01-01

    Full Text Available For the problem of easily losing track target when obstacles appear in intelligent robot target tracking, this paper proposes a target tracking algorithm integrating reduced dimension optimal Kalman filtering algorithm based on phase-path volume integral with Camshift algorithm. After analyzing the defects of Camshift algorithm, compare the performance with the SIFT algorithm and Mean Shift algorithm, and Kalman filtering algorithm is used for fusion optimization aiming at the defects. Then aiming at the increasing amount of calculation in integrated algorithm, reduce dimension with the phase-path volume integral instead of the Gaussian integral in Kalman algorithm and reduce the number of sampling points in the filtering process without influencing the operational precision of the original algorithm. Finally set the target centroid position from the Camshift algorithm iteration as the observation value of the improved Kalman filtering algorithm to fix predictive value; thus to make optimal estimation of target centroid position and keep the target tracking so that the robot can understand the environmental scene and react in time correctly according to the changes. The experiments show that the improved algorithm proposed in this paper shows good performance in target tracking with obstructions and reduces the computational complexity of the algorithm through the dimension reduction.

  3. Microlensed image centroid motions by an exotic lens object with negative convergence or negative mass

    Kitamura, Takao; Nakajima, Koki; Hagiwara, Chisaki; Asada, Hideki

    2013-01-01

    Gravitational lens models with negative convergence (surface mass density projected onto the lens plane) inspired by modified gravity theories, exotic matter and energy have been recently examined to discuss possible demagnification of images and gravitational lensing shear, in such a way that a static and spherically symmetric modified spacetime metric depends on the inverse distance to the power of positive $n$ ($n=1$ for Schwarzschild metric, $n=2$ for Ellis wormhole) in the weak-field approximation [Kitamura, Nakajima and Asada, PRD 87, 027501 (2013), Izumi et al. to be published in PRD (2013)]. Some of the exotic lens models cause the attractive force on light rays like a convex lens, whereas the others are repulsive on light rays like a concave lens. The present paper considers microlensed image centroid motions by the exotic lens models. Numerical calculations show that, for large $n$ cases in the convex-type models, the centroid shift from the source position might move on a multiply-connected curve l...

  4. A path method for finding energy barriers and minimum energy paths in complex micromagnetic systems

    Minimum energy paths and energy barriers are calculated for complex micromagnetic systems. The method is based on the nudged elastic band method and uses finite-element techniques to represent granular structures. The method was found to be robust and fast for both simple test problems as well as for large systems such as patterned granular media. The method is used to estimate the energy barriers in CoCr-based perpendicular recording media

  5. A simple method for finding the scattering coefficients of quantum graphs

    Cottrell, Seth S. [Department of Physics and Astronomy, Hunter College of the City University of New York, New York, New York 10065 (United States)

    2015-09-15

    Quantum walks are roughly analogous to classical random walks, and similar to classical walks they have been used to find new (quantum) algorithms. When studying the behavior of large graphs or combinations of graphs, it is useful to find the response of a subgraph to signals of different frequencies. In doing so, we can replace an entire subgraph with a single vertex with variable scattering coefficients. In this paper, a simple technique for quickly finding the scattering coefficients of any discrete-time quantum graph will be presented. These scattering coefficients can be expressed entirely in terms of the characteristic polynomial of the graph’s time step operator. This is a marked improvement over previous techniques which have traditionally required finding eigenstates for a given eigenvalue, which is far more computationally costly. With the scattering coefficients we can easily derive the “impulse response” which is the key to predicting the response of a graph to any signal. This gives us a powerful set of tools for rapidly understanding the behavior of graphs or for reducing a large graph into its constituent subgraphs regardless of how they are connected.

  6. The study on the centroid of the lattice point in the plane%平面格点形心问题研究

    慕运动

    2001-01-01

    The centroid of the lattice point in the plane is studied in this paper. Let n(k) be the smallest integer n such that, given any n latice points in the plane, some k of them have a lattice point centroid. Erickson gave a proof of n(3)=9 by the method of finite projective plane in [1]. Firstly, this paper gives a new and simple proof of n(3)=9 by geometric method and the pigeonhole principle. Secondly, it improves the upper bound of n(4).%在组合论和数论中,平面格点形心问题是对给定的自然数k,求这样的最小整数n(k),使得当n≥n(k)时,平面上任意几个格点中必存在k个格点的形心也是格点。显然n(1)=1,并容易求出n(2)=5。文献[1]用较复杂的组合设计方法确定出n(3)=9。本文提出一种简易的方法,给出n(3)=9的新证,并得到n(4)的改进上界。

  7. Bayesian data augmentation methods for the synthesis of qualitative and quantitative research findings

    Crandell, Jamie L.; Voils, Corrine I.; Chang, YunKyung; Sandelowski, Margarete

    2011-01-01

    The possible utility of Bayesian methods for the synthesis of qualitative and quantitative research has been repeatedly suggested but insufficiently investigated. In this project, we developed and used a Bayesian method for synthesis, with the goal of identifying factors that influence adherence to HIV medication regimens. We investigated the effect of 10 factors on adherence. Recognizing that not all factors were examined in all studies, we considered standard methods for dealing with missin...

  8. Towards understanding household-level forest reliance in Cambodia - study sites, methods, and preliminary findings

    Ra, Koy; Pichdara, Lonn; Dararath, Yem;

    There is growing international interest in the role of forests in poverty prevention and reduction. In consequence, this broad area of investigation has been subject to increased research; one major international research project is that facilitated by the Poverty Environment Network (PEN). This...... project covers a large number of sites in 26 countries throughout the tropics. The present report contains contextual details, methodological information and preliminary findings for the PEN sites in Cambodia....

  9. An Approach for registration method to find corresponding mass lesions in temporal mammogram pairs

    Prof. Samir Kumar Bandyopadhyay

    2010-01-01

    Radiologists generally use multiple mammographic views to detect and characterize suspiciousregions. When radiologists discover a suspicious lesion in one view, they try to find a corresponding lesion in the other views. Views from different projections, typically cranio caudal (CC) and medio lateral oblique (MLO) views, allow for a better realization of the lesion. Most current computer aided detection (CAD) systems differ considerably from radiologists in the way they use multiple views. Th...

  10. An MLE method for finding LKB NTCP model parameters using Monte Carlo uncertainty estimates

    The aims of this work were to establish a program to fit NTCP models to clinical data with multiple toxicity endpoints, to test the method using a realistic test dataset, to compare three methods for estimating confidence intervals for the fitted parameters and to characterise the speed and performance of the program.

  11. The functional variable method for finding exact solutions of some nonlinear time-fractional differential equations

    Wenjun Liu; Kewang Chen

    2013-09-01

    In this paper, we implemented the functional variable method and the modified Riemann–Liouville derivative for the exact solitary wave solutions and periodic wave solutions of the time-fractional Klein–Gordon equation, and the time-fractional Hirota–Satsuma coupled KdV system. This method is extremely simple but effective for handling nonlinear time-fractional differential equations.

  12. A New Method for Finding Point Sources in High-energy Neutrino Data

    Fang, Ke

    2016-01-01

    The IceCube collaboration has reported the first detection of high-energy astrophysical neutrinos including $\\sim 50$ high-energy starting events, but no individual sources have been identified. It is therefore important to develop the most sensitive and efficient possible algorithms to identify point sources of these neutrinos. The most popular current method works by exploring a dense grid of possible directions to individual sources, and identifying the single direction with the maximum probability of having produced multiple detected neutrinos. This method has numerous strengths, but it is computationally intensive and, because it focuses on the single best location for a point source, additional point sources are not included in the evidence. We propose a new maximum likelihood method that uses the angular separations between all pairs of neutrinos in the data. Unlike existing autocorrelation methods for this type of analysis, which also use angular separations between neutrino pairs, our method incorpor...

  13. A simple way of finding linked and antagonistic characters by means of table of characters used in the dendrite method

    Tadeusz Kowal

    2015-05-01

    Full Text Available The author gives a new methodical solution based on the table of characters used in taxonomic examinations by the dendrite method worked out for the species of Delia Dum., Spergula L. and Spergularia Presl. growing in Poland. This methodical solution shows a simple way to find conjugate and antagonistic characters in the examined species and to determine which characters are related to each other in different organs.

  14. An alternative computational method for finding the minimum-premium insurance portfolio

    Katsikis, Vasilios N.

    2016-06-01

    In this article, we design a computational method, which differs from the standard linear programming techniques, for computing the minimum-premium insurance portfolio. The corresponding algorithm as well as a Matlab implementation are provided.

  15. DiffCoEx : a simple and sensitive method to find differentially coexpressed gene modules

    Tesson, Bruno M.; Breitling, Rainer; Jansen, Ritsert C.

    2010-01-01

    Background: Large microarray datasets have enabled gene regulation to be studied through coexpression analysis. While numerous methods have been developed for identifying differentially expressed genes between two conditions, the field of differential coexpression analysis is still relatively new. M

  16. DiffCoEx: a simple and sensitive method to find differentially coexpressed gene modules

    Breitling Rainer; Tesson Bruno M; Jansen Ritsert C

    2010-01-01

    Abstract Background Large microarray datasets have enabled gene regulation to be studied through coexpression analysis. While numerous methods have been developed for identifying differentially expressed genes between two conditions, the field of differential coexpression analysis is still relatively new. More specifically, there is so far no sensitive and untargeted method to identify gene modules (also known as gene sets or clusters) that are differentially coexpressed between two condition...

  17. A numerical method for finding sign-changing solutions of superlinear Dirichlet problems

    Neuberger, J.M.

    1996-12-31

    In a recent result it was shown via a variational argument that a class of superlinear elliptic boundary value problems has at least three nontrivial solutions, a pair of one sign and one which sign changes exactly once. These three and all other nontrivial solutions are saddle points of an action functional, and are characterized as local minima of that functional restricted to a codimension one submanifold of the Hilbert space H-0-1-2, or an appropriate higher codimension subset of that manifold. In this paper, we present a numerical Sobolev steepest descent algorithm for finding these three solutions.

  18. A simple method for finding crystallite distribution by size based on the profile of x-ray diffraction lines

    The present communication proposes a mathematical method of finding crystallite distribution by size. The method was developed in recent years to process small-angle scattering data and is based on a modified Laplace method. The proposed method is less sensitive to background level and requires fewer experimental points over a wide angle range than harmonic analysis of the form of the diffraction lines (HAFXL). Experimental verification of the method obtained from two powder samples of nickel oxide is presented. 6 refs., 2 figs., 2 tabs

  19. DiffCoEx: a simple and sensitive method to find differentially coexpressed gene modules

    Breitling Rainer

    2010-10-01

    Full Text Available Abstract Background Large microarray datasets have enabled gene regulation to be studied through coexpression analysis. While numerous methods have been developed for identifying differentially expressed genes between two conditions, the field of differential coexpression analysis is still relatively new. More specifically, there is so far no sensitive and untargeted method to identify gene modules (also known as gene sets or clusters that are differentially coexpressed between two conditions. Here, sensitive and untargeted means that the method should be able to construct de novo modules by grouping genes based on shared, but subtle, differential correlation patterns. Results We present DiffCoEx, a novel method for identifying correlation pattern changes, which builds on the commonly used Weighted Gene Coexpression Network Analysis (WGCNA framework for coexpression analysis. We demonstrate its usefulness by identifying biologically relevant, differentially coexpressed modules in a rat cancer dataset. Conclusions DiffCoEx is a simple and sensitive method to identify gene coexpression differences between multiple conditions.

  20. The Findings from the OECD/NEA/CSNI UMS (Uncertainty Method Study)

    Within licensing procedures there is the incentive to replace the conservative requirements for code application by a 'best estimate' concept supplemented by an uncertainty analysis to account for predictive uncertainties of code results. Methods have been developed to quantify these uncertainties. The Uncertainty Methods Study (UMS) Group, following a mandate from CSNI (Committee on the Safety of Nuclear Installations) of OECD/NEA (Organization for Economic Cooperation and Development / Nuclear Energy Agency), has compared five methods for calculating the uncertainty in the predictions of advanced 'best estimate' thermal-hydraulic codes. Most of the methods identify and combine input uncertainties. The major differences between the predictions of the methods came from the choice of uncertain parameters and the quantification of the input uncertainties, i.e. the wideness of the uncertainty ranges. Therefore, suitable experimental and analytical information has to be selected to specify these uncertainty ranges or distributions. After the closure of the Uncertainty Method Study (UMS) and after the report was issued comparison calculations of experiment LSTF-SB-CL-18 were performed by University of Pisa using different versions of the RELAP 5 code. It turned out that the version used by two of the participants calculated a 170 K higher peak clad temperature compared with other versions using the same input deck. This may contribute to the differences of the upper limit of the uncertainty ranges. A 'bifurcation' analysis was also performed by the same research group also providing another way of interpreting the high temperature peak calculated by two of the participants. (authors)

  1. Path integral centroid molecular dynamics simulations of semiinfinite slab and bulk liquid of para-hydrogen

    Kinugawa, Kenichi [Nara Women`s Univ., Nara (Japan). Dept. of Chemistry

    1998-10-01

    It has been unsuccessful to solve a set of time-dependent Schroedinger equations numerically for many-body quantum systems which involve, e.g., a number of hydrogen molecules, protons, and excess electrons at a low temperature, where quantum effect evidently appears. This undesirable situation is fatal for the investigation of real low-temperature chemical systems because they are essentially composed of many quantum degrees of freedom. However, if we use a new technique called `path integral centroid molecular dynamics (CMD) simulation` proposed by Cao and Voth in 1994, the real-time semi-classical dynamics of many degrees of freedom can be computed by utilizing the techniques already developed in the traditional classical molecular dynamics (MD) simulations. Therefore, the CMD simulation is expected to be very powerful tool for the quantum dynamics studies or real substances. (J.P.N.)

  2. Centroid position measurements and subpixel sensitivity variations with the MAMA detector

    Morgan, Jeffrey S.; Slater, D. C.; Timothy, John G.; Jenkins, E. B.

    1989-01-01

    Initial measurements of the position sensitivity of a visible-light multianode microchannel array detector show that centroid calculations for image spots are accurate to better than 0.04 pixels even with sources that are essentially delta functions at the photocathode.Subpixel sensitivity variations of 10-15 percent are typically found for pixels in the array. Variations as large as 30 percent are possible in the worst conditions. These variations limit the photometric accuracy of the detector when very small scale features are observed. The photometric accuracy and the position sensitivity of the detector appear to be limited by cross-coupling effects within the anode array. Initial measurements with more recent designs of the detector show that most or all of this cross-coupling has been eliminated.

  3. Energy Centroids of Spin $I$ States by Random Two-body Interactions

    Zhao, Y M; Ogawa, K

    2005-01-01

    In this paper we study the behavior of energy centroids (denoted as $\\bar{E_I}$) of spin $I$ states in the presence of random two-body interactions, for systems ranging from very simple systems (e.g. single-$j$ shell for very small $j$) to very complicated systems (e.g., many-$j$ shells with different parities and with isospin degree of freedom). Regularities of $\\bar{E_I}$'s discussed in terms of the so-called geometric chaoticity (or quasi-randomness of two-body coefficients of fractional parentage) in earlier works are found to hold even for very simple systems in which one cannot assume the geometric chaoticity. It is shown that the inclusion of isospin and parity does not "break" the regularities of $\\bar{E_I}$'s.

  4. Music therapists’ practice-based research in cancer and palliative care: Creative methods and situated findings

    Philippa Barry

    2009-11-01

    Full Text Available Although randomized controlled trials are described as the gold standard in health care research, their superiority is being questioned in palliative care which is focused on addressing individualized needs to maximize life quality. We use creative practice-based research to examine the usefulness of our music therapy work amongst people with life threatening conditions. Examined voices include “collective” (patients, visitors, staff, and music therapist, "their” (patients or caregivers, "our” (a group of music therapists, and "my voice” (one music therapist. Data sources have included clinical journals, semi-structured questionnaires, interview responses, a focus group, reflexive groupwork supervision transcripts, and patients’ song lyrics. Findings, situated within varied theoretic lenses, substantiate music therapy’s role in oncology and palliative care settings. Readers are invited to devise creative ways to voice their clients’, bystanders’, and own wisdom about music therapy to meaningfully extend the knowledge base.

  5. The Dynamics of Poverty in the United States: A Review of Data, Methods, and Findings

    Cellini, Stephanie Riegg; McKernan, Signe-Mary; Ratcliffe, Caroline

    2008-01-01

    This paper reviews the literature on poverty dynamics in the U.S. It surveys the most prevalent data, theories, and methods used to answer three key questions: How likely are people to enter, exit, and reenter poverty? How long do people remain in poverty? And what events are associated with entering and exiting poverty? The paper then analyzes…

  6. A Simple Method to Find out when an Ordinary Differential Equation Is Separable

    Cid, Jose Angel

    2009-01-01

    We present an alternative method to that of Scott (D. Scott, "When is an ordinary differential equation separable?", "Amer. Math. Monthly" 92 (1985), pp. 422-423) to teach the students how to discover whether a differential equation y[prime] = f(x,y) is separable or not when the nonlinearity f(x, y) is not explicitly factorized. Our approach is…

  7. A NEW PROOF OF JORDAN'S CENTROID THEOREM%约当重心定理的一个新证明

    Skrun.,R; 李冠英

    1999-01-01

    Jordan's Centroid Theorem (1869) states th at the centroid of a tree consists of either a single vertex or a pair of adjace nt vertices. This paper presents a new proof of this theorem.%约当重心定理(1869年)提出,一棵树的重心不是由一个单一的顶点组成,就是由一对相邻的顶点组成.这篇文章提出了一个证明这个定理的新方法.

  8. A Proposal to Speed up the Computation of the Centroid of an Interval Type-2 Fuzzy Set

    Carlos E. Celemin

    2013-01-01

    Full Text Available This paper presents two new algorithms that speed up the centroid computation of an interval type-2 fuzzy set. The algorithms include precomputation of the main operations and initialization based on the concept of uncertainty bounds. Simulations over different kinds of footprints of uncertainty reveal that the new algorithms achieve computation time reductions with respect to the Enhanced-Karnik algorithm, ranging from 40 to 70%. The results suggest that the initialization used in the new algorithms effectively reduces the number of iterations to compute the extreme points of the interval centroid while precomputation reduces the computational cost of each iteration.

  9. A Novel Approach Based on MEMS-Gyro's Data Deep Coupling for Determining the Centroid of Star Spot

    Xing Fei; Chen Nan; You Zheng; Sun Ting

    2012-01-01

    The traditional approach of star tracker for determining the centroid of spot requires enough energy and good shape, so a relatively long exposure time and stable three-axis state become necessary conditions to maintain high accuracy, these limit its update rate and dynamic performance. In view of these issues, this paper presents an approach for determining the centroid of star spot which based on MEMS-Gyro's data deep coupling, it achieves the deep fusion of the data of star tracker and MEM...

  10. An alignment-free method to find and visualise rearrangements between pairs of DNA sequences.

    Pratas, Diogo; Silva, Raquel M; Pinho, Armando J; Ferreira, Paulo J S G

    2015-01-01

    Species evolution is indirectly registered in their genomic structure. The emergence and advances in sequencing technology provided a way to access genome information, namely to identify and study evolutionary macro-events, as well as chromosome alterations for clinical purposes. This paper describes a completely alignment-free computational method, based on a blind unsupervised approach, to detect large-scale and small-scale genomic rearrangements between pairs of DNA sequences. To illustrate the power and usefulness of the method we give complete chromosomal information maps for the pairs human-chimpanzee and human-orangutan. The tool by means of which these results were obtained has been made publicly available and is described in detail. PMID:25984837

  11. Exploring Community Gardens in a Health Disparate Population: Findings from a Mixed Methods Pilot Study

    Zanko, Ashley; Price, Bryan; Bonner, Jennifer; Hill, Jennie L.; Zoellner, Jamie M

    2012-01-01

    Background: Despite recommendations, there have been few efforts to apply the community-based participatory research (CBPR) approach in the development, implementation, and evaluation of community gardens. Objectives: As guided by the CBPR approach and grounded in a social-ecological model and behavioral theory, the purpose of this mixed methods study was to understand opinions and interests in developing and implementing a community garden and to understand factors impacting fruit, vegetable...

  12. Finding the buckling load of non-uniform columns using the iteration perturbation method

    Aref Afsharfard; Anooshiravan Farshidianfar

    2014-01-01

    The aim of this study is to calculate the critical load of variable inertia columns. The example studied in this paper can be used as a paradigm for other non-uniform columns. The wavelength of equivalent vibratory system is used to calculate the critical load of the trigonometrically varied inertia column. In doing so, the equilibrium equation of the column is theoretically studied using the perturbation method. Accuracy of the calculated results is evaluated by comparing the solution with n...

  13. THE STATISTICAL METHOD FOR FINDING THE RESPONSE FOR N RANDOM EXCITATION OF THE INVERTED PENDULUM

    Marinică STAN

    2013-05-01

    Full Text Available We present a method for estimating the power spectral density of the stationary response of oscillatorwith a nonlinear restoring force under external stochastic wide-band excitation. An equivalent linear system isderived, from which the power spectral density is deduced. We consider an inverted pendulum suspendedsubjected to white noise excitation with a random number n random excitations simultaneously applied. Themethod will be briefly discussed in the following sections

  14. Gradient Method for Finding Optimal Scheduling in Infinite Dimensional Models of Chemotherapy

    Smieja, Jaroslaw; Swierniak, Andrzej; Duda, Zdzislaw

    2000-01-01

    One of the major obstacles against succesful chemotherapy of cancer is the emergence of resistance of cancer cells to cytotoxic agents. Applying optimal control theory to mathematical models of cell cycle dynamics can be a very efficient method to understand and, eventually, overcome this problem. Results that have been hitherto obtained have already helped to explain some observed phenomena, concerning dynamical properties of cancer populations. Because of recent progress in understanding th...

  15. An alignment-free method to find and visualise rearrangements between pairs of DNA sequences

    Pratas, Diogo; Silva, Raquel M; Pinho, Armando J.; Ferreira, Paulo J.S.G.

    2015-01-01

    Species evolution is indirectly registered in their genomic structure. The emergence and advances in sequencing technology provided a way to access genome information, namely to identify and study evolutionary macro-events, as well as chromosome alterations for clinical purposes. This paper describes a completely alignment-free computational method, based on a blind unsupervised approach, to detect large-scale and small-scale genomic rearrangements between pairs of DNA sequences. To illustrat...

  16. Healthy Bread Initiative: Methods, Findings, and Theories—Isfahan Healthy Heart Program

    Talaei, Mohammad; Mohammadifard, Noushin; Khaje, Mohammad-Reza; Sarrafzadegan, Nizal; Sajjadi, Firoozeh; Alikhasi, Hasan; Maghroun, Maryam; Iraji, Farhad; Ehteshami, Shahram

    2013-01-01

    The scientific evidences show that the content, baking methods, and types of bread can make health impacts. Bread, as a major part of Iranian diet, demonstrates a significant potential to be targeted as health promotion subject. Healthy Food for Healthy Communities (HFHC) was a project of Isfahan Healthy Heart Program (IHHP), consisting of a wide variety of strategies, like Healthy Bread (HB) Initiative. The HB Initiative was designed to improve the behaviour of both producers and consumers, ...

  17. A critical assessment of theoretical methods for finding reaction pathways and transition states of surface processes

    The performance of a variety of techniques for locating transition states on potential energy surfaces is evaluated within the density functional theory framework. Diffusion of a water molecule across NaCl(001) and HCl bond breaking on the same surface are treated as general test cases; the former is an example of a low barrier diffusion process and the latter an example of a relatively high barrier covalent bond rupture event. The methods considered include the nudged elastic band (NEB), Dewar, Healy and Stewart (DHS), dimer, constrained optimization (CO), activation-relaxation technique (ART) and one-side growing string (OGS) as well as novel combinations of the DHS with growing string (DHS + GS) and DHS plus climbing image (CI-DHS). A key conclusion to come from this study is that the NEB method is relatively fast, especially when just a single (climbing) image is used. Indeed, using more images represents an unnecessary computational burden for our set of processes. The dimer method exhibits variable performance; being poor for the water diffusion processes, which have small activation energies, but much more efficient for the HCl bond breaking process which has a higher barrier. When only a poor initial guess of the transition state geometry is available, the CI-DHS scheme is one of the most efficient techniques considered. And as a means to quickly establish an approximate minimum energy pathway the DHS + GS scheme offers some potential.

  18. Lead finding from whole plant of Marrubium vulgare L. with Hepatoprotective Potentials through in silico methods

    Amita Verma; Mubashir Masoodi; Bahar Ahmed

    2012-01-01

    Objective: In the present study an attempt has been made to study the antihepatotoxic activity of active compounds in this plant through in silico methods. Methods: We have taken 12 compounds form this plant. All the compounds were further subjected to molecular propertied prediction and drug likeness by Molinspiration and found in compliance with Lipinski’s rule of five. Biochemical parameters like SGOT and SGPT were determined by Reitman and Frankel, ALP by Kind and King, TP by reported methods of Wooton. Results: All the compounds were showed expected similar bioactivity especially in case of enzyme inhibition. Compound Vulgarin showed no violation with good drug likeness score and biological activity as compare to standard drug Silibinin. Vulgarin exhibited a significant antihepatotoxic activity by reducing the elevated levels of serum enzymes such as serum glutamate oxaloacetate transaminase (SGOT) serum glutamate pyruvate oxaloacetate transaminase (SGPT) and alkaline phosphatase (ALP) while the total protein (TP) levels were increased when compared with standard drug silymarin against CCl4-induced toxicity in Wistar rats. These biochemical observations were also supplemented by histopathological examinations of the liver sections. Conclusions: We found that Vulgarin one of the twelve compounds is showed better drug likeness and biological activity against Silibinin. So this particular compound can be taken as lead compound for further drug discovery for hepatotoxic activity.

  19. Adaptive Ant Colony Clustering Method Applied to Finding Closely Communicating Community

    Yan Liu

    2012-02-01

    Full Text Available The investigation of community structures in networks is an important issue in many domains and disciplines. Closely communicating community is different from the traditional community which emphasize particularly on structure or context. Our previous method played more emphasis on the feasibility that ant colony algorithm applied to community detection. However the essence of closely communicating community did not be described clearly. In this paper, the definition of closely communicating community is put forward firstly, the four features are described and corresponding methods are introduced to achieve the value of features between each pair. Meanwhile, pair propinquity and local propinquity are put forward and used to guide ants’ decision. Based on the previous work, the closely communicating community detection method is improved in four aspects of adaptive adjusting, which are entropy based weight modulation, combining historical paths and random wandering to select next coordination, the strategy of forcing unloading and the adaptive change of ant’s eyesight. The value selection of parameters is discussed in the portion of experiments, and the results also reveal the improvement of our algorithm in adaptive djusting.

  20. The SHIELD (Safety & Health Improvement: Enhancing Law Enforcement Departments) Study: Mixed Methods Longitudinal Findings.

    Kuehl, Kerry S; Elliot, Diane L; MacKinnon, David P; O'Rourke, Holly P; DeFrancesco, Carol; Miočević, Milica; Valente, Matthew; Sleigh, Adriana; Garg, Bharti; McGinnis, Wendy; Kuehl, Hannah

    2016-05-01

    The SHIELD (Safety & Health Improvement: Enhancing Law Enforcement Departments) Study is a worksite wellness team-based intervention among police and sheriff departments assessing the program's effectiveness to reduce occupational risks and unhealthy lifestyle behaviors. The SHIELD program focused on improving diet, physical activity, body weight and sleep, and reducing the effects of unhealthy stress and behaviors, such as tobacco and substance abuse. The SHIELD team-based health promotion program was found to be feasible and effective at 6 months in improving diet, sleep, stress, and overall quality of life of law enforcement department personnel. Both intervention and control groups were followed for 24 months, and we report those durability findings, along with qualitative group interview results that provide insight into the changes of the long-term outcomes. Long-term effects were observed for consumption of fruits and vegetables, and there was some evidence for effects on tobacco and alcohol use. Assessment of dietary habits, physical activity behaviors, weight loss maintenance, and substance use is rare more than 1 year following an intervention, and in general, initial positive changes do not persist in prior research. The SHIELD program was feasible, effective, and durable for improving dietary changes. PMID:27158956

  1. 1001 optimal PDB structure alignments: integer programming methods for finding the maximum contact map overlap.

    Caprara, Alberto; Carr, Robert; Istrail, Sorin; Lancia, Giuseppe; Walenz, Brian

    2004-01-01

    Protein structure comparison is a fundamental problem for structural genomics, with applications to drug design, fold prediction, protein clustering, and evolutionary studies. Despite its importance, there are very few rigorous methods and widely accepted similarity measures known for this problem. In this paper we describe the last few years of developments on the study of an emerging measure, the contact map overlap (CMO), for protein structure comparison. A contact map is a list of pairs of residues which lie in three-dimensional proximity in the protein's native fold. Although this measure is in principle computationally hard to optimize, we show how it can in fact be computed with great accuracy for related proteins by integer linear programming techniques. These methods have the advantage of providing certificates of near-optimality by means of upper bounds to the optimal alignment value. We also illustrate effective heuristics, such as local search and genetic algorithms. We were able to obtain for the first time optimal alignments for large similar proteins (about 1,000 residues and 2,000 contacts) and used the CMO measure to cluster proteins in families. The clusters obtained were compared to SCOP classification in order to validate the measure. Extensive computational experiments showed that alignments which are off by at most 10% from the optimal value can be computed in a short time. Further experiments showed how this measure reacts to the choice of the threshold defining a contact and how to choose this threshold in a sensible way. PMID:15072687

  2. Finding a needle by removing the haystack: A spatio-temporal normalization method for geophysical data

    Pavlidou, E.; van der Meijde, M.; van der Werff, H.; Hecker, C.

    2016-05-01

    We introduce a normalization algorithm which highlights short-term, localized, non-periodic fluctuations in hyper-temporal satellite data by dividing each pixel by the mean value of its spatial neighbourhood set. In this way we suppress signal patterns that are common in the central and surrounding pixels, utilizing both spatial and temporal information at different scales. We test the method on two subsets of a hyper-temporal thermal infra-red (TIR) dataset. Both subsets are acquired from the SEVIRI instrument onboard the Meteosat-9 geostationary satellite; they cover areas with different spatiotemporal TIR variability. We impose artificial fluctuations on the original data and apply a window-based technique to retrieve them from the normalized time series. We show that localized short-term fluctuations as low as 2 K, which were obscured by large-scale variable patterns, can be retrieved in the normalized time series. Sensitivity of retrieval is determined by the intrinsic variability of the normalized TIR signal and by the amount of missing values in the dataset. Finally, we compare our approach with widely used techniques of statistical and spectral analysis and we discuss the improvements introduced by our method.

  3. Application of geo-microbial prospecting method for finding oil and gas reservoirs

    Rasheed, M. A.; Hasan, Syed Zaheer; Rao, P. L. Srinivasa; Boruah, Annapurna; Sudarshan, V.; Kumar, B.; Harinarayana, T.

    2015-03-01

    Microbial prospecting of hydrocarbons is based on the detection of anomalous population of hydrocarbon oxidizing bacteria in the surface soils, indicates the presence of subsurface oil and gas accumulation. The technique is based on the seepage of light hydrocarbon gases such as C1-C4 from the oil and gas pools to the shallow surface that provide the suitable conditions for the development of highly specialized bacterial population. These bacteria utilize hydrocarbon gases as their only food source and are found enriched in the near surface soils above the hydrocarbon bearing structures. The methodology involves the collection of soil samples from the survey area, packing, preservation and storage of samples in pre-sterilized sample bags under aseptic and cold conditions till analysis and isolation and enumeration of hydrocarbon utilizing bacteria such as methane, ethane, propane, and butane oxidizers. The contour maps for the population density of hydrocarbon oxidizing bacteria are drawn and the data can be integrated with geological, geochemical, geophysical methods to evaluate the hydrocarbon prospect of an area and to prioritize the drilling locations thereby reducing the drilling risks and achieve higher success in petroleum exploration. Microbial Prospecting for Oil and Gas (MPOG) method success rate has been reported to be 90%. The paper presents details of microbial prospecting for oil and gas studies, excellent methodology, future development trends, scope, results of study area, case studies and advantages.

  4. 20 CFR 404.283 - Recomputation under method other than that used to find your primary insurance amount.

    2010-04-01

    ... used to find your primary insurance amount. 404.283 Section 404.283 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL OLD-AGE, SURVIVORS AND DISABILITY INSURANCE (1950- ) Computing Primary Insurance Amounts Recomputing Your Primary Insurance Amount § 404.283 Recomputation under method other than that used to...

  5. Preliminary Findings of a Format-based Foreign Language Teaching Method for School Children in the Basque Country.

    Azpillaga, Beronika; Arzamendi, Jesus; Etxeberria, Feli; Garagorri, Xabier; Lindsay, Diana; Joaristi, Luis

    2001-01-01

    Describes the preliminary findings in the Basque Country of a project shared by four European countries to teach a second language or a foreign language to preschool and school-age children. The method used to teach the foreign language--English--is based on the use of dramatized formats. Examines level of language proficiency achieved with each…

  6. Finding the buckling load of non-uniform columns using the iteration perturbation method

    Aref Afsharfard

    2014-01-01

    Full Text Available The aim of this study is to calculate the critical load of variable inertia columns. The example studied in this paper can be used as a paradigm for other non-uniform columns. The wavelength of equivalent vibratory system is used to calculate the critical load of the trigonometrically varied inertia column. In doing so, the equilibrium equation of the column is theoretically studied using the perturbation method. Accuracy of the calculated results is evaluated by comparing the solution with numerical results. Effect of improving the initial guess on the solution accuracy is investigated. Effects of varying parameters of the trigonometrically varied inertia and the uniformly tapered columns on their stability behavior are studied. Finally, using the so-called “perfectibility” parameter, two design goals, i.e., being lightweight and being strong, are studied for the discussed columns.

  7. Three-Dimensional Computed Tomography as a Method for Finding Die Attach Voids in Diodes

    Brahm, E. N.; Rolin, T. D.

    2010-01-01

    NASA analyzes electrical, electronic, and electromechanical (EEE) parts used in space vehicles to understand failure modes of these components. The diode is an EEE part critical to NASA missions that can fail due to excessive voiding in the die attach. Metallography, one established method for studying the die attach, is a time-intensive, destructive, and equivocal process whereby mechanical grinding of the diodes is performed to reveal voiding in the die attach. Problems such as die attach pull-out tend to complicate results and can lead to erroneous conclusions. The objective of this study is to determine if three-dimensional computed tomography (3DCT), a nondestructive technique, is a viable alternative to metallography for detecting die attach voiding. The die attach voiding in two- dimensional planes created from 3DCT scans was compared to several physical cross sections of the same diode to determine if the 3DCT scan accurately recreates die attach volumetric variability

  8. A comparative method for finding and folding RNA secondary structures within protein-coding regions

    Pedersen, Jakob Skou; Meyer, Irmtraud Margret; Forsberg, Roald; Simmonds, Peter; Hein, Jotun

    2004-01-01

    Existing computational methods for RNA secondary-structure prediction tacitly assume RNA to only encode functional RNA structures. However, experimental studies have revealed that some RNA sequences, e.g. compact viral genomes, can simultaneously encode functional RNA structures as well as proteins...... that RNA-DECODER's parameters can be automatically trained to successfully fold known secondary structures within the HCV genome. We scan the genomes of HCV and polio virus for conserved secondary-structure elements, and analyze performance as a function of available evolutionary information. On known...... secondary structures, RNA-DECODER shows a sensitivity similar to the programs MFOLD, PFOLD and RNAALIFOLD. When scanning the entire genomes of HCV and polio virus for structure elements, RNA-DECODER's results indicate a markedly higher specificity than MFOLD, PFOLD and RNAALIFOLD....

  9. Combined Calibration Method and its Realization for Direction Finding Antenna Systems with Patch Antennas

    R. Seller

    2007-09-01

    Full Text Available A novel radio channel compensation method aiming to give optimal calibration for microstrip antenna array systems is presented in this paper, realized for an actual DOA measurement antenna system using microstrip antennas to sample the electromagnetic field, operating at 4.5GHz. This new approach considers mismatch between antennas and channel RF ports, channel transmission inequalities, and also decreases the effects of multipath propagation components of calibration reference signals by placing the calibration reference signal feeding network on the microstrip antenna array bearer, directly beside the antenna patches. It is combined with orthogonal spread spectrum calibration signal utility for continuous uninterrupted measurements. The spread spectrum calibration signal is orthogonal to the continuous wave (CW signal to be measured, therefore, the 2 signals can be separated in the receiver, enabling them to be present simultaneously. DOA measurement results are shown, measured with the realized integrated microstrip patch antenna array with calibration network hardware.

  10. Lead finding from Pterocarpous santilanus with hepatoprotective potentials through in silico methods

    B.K.Manjunatha

    2010-08-01

    Full Text Available Review of the literature revealed that, many compounds have been isolated from P.santalinus but there is no report of screening its potency in protecting CCl4 induced liver damage. Hence in the present study an attempt has been made to study the hepatoprotective potency of the active constituents in P.santalinus through in silico methods.Lipenski’s Rule of Five was applied on all the compounds to evaluate their drug likeness and pharmacological properties. Only the compounds satisfying the Lipenski’s criteria were considered for further computational operations. Compounds that cleared the Lipenski’s barrier were prepared for docking studies by their energyminimization in Marvin Sketch. HBx protein of hepatitis B virus served as a target (receptor for docking studies. Its structure was retrieved from PDB (ID:3I7H. Energy minimized compounds were subjected to receptor-ligand interaction study using Hex docking tool. Based on the docking scores of energy minimized compounds it wasconcluded that pterocarpol and cryptomeridiol required minimum energy to bind to HBx. ADME-TOX analysis of these compounds showed that their AMES test value was significantly lower than some of the ommercially and widely used drugs to treat Hepatisis. Hence these compounds hold good prospective of being used as medicine thattargets HBx for hepatitis treatment.

  11. A COMPARATIVE STUDY TO FIND A SUITABLE METHOD FOR TEXT DOCUMENT CLUSTERING

    Dr.M.Punithavalli

    2012-01-01

    Full Text Available Text mining is used in various text related tasks such as information extraction, concept/entity extraction,document summarization, entity relation modeling (i.e., learning relations between named entities,categorization/classification and clustering. This paper focuses on document clustering, a field of textmining, which groups a set of documents into a list of meaningful categories. The main focus of thispaper is to present a performance analysis of various techniques available for document clustering. Theresults of this comparative study can be used to improve existing text data mining frameworks andimprove the way of knowledge discovery. This paper considers six clustering techniques for documentclustering. The techniques are grouped into three groups namely Group 1 - K-means and its variants(traditional K-means and K* Means algorithms, Group 2 - Expectation Maximization and its variants(traditional EM, Spherical Gaussian EM algorithm and Linear Partitioning and Reallocation clustering(LPR using EM algorithms, Group 3 - Semantic-based techniques (Hybrid method and Feature-basedalgorithms. A total of seven algorithms are considered and were selected based on their popularity inthe text mining field. Several experiments were conducted to analyze the performance of the algorithmand to select the winner in terms of cluster purity, clustering accuracy and speed of clustering.

  12. Examining the effects of interprofessional problem-based clinical ethics: Findings from a mixed methods study.

    Chou, Fremen Chihchen; Kwan, Chiu-Yin; Hsin, Dena Hsin-Chen

    2016-05-01

    Understanding how interprofessional education (IPE) works in learning clinical ethics via problem-based learning (PBL) and how different professions' perspectives influence each other in this setting may inform future IPE. Eighty-nine students participated in a clinical ethics PBL and were assigned into three study groups, i.e., medical, nursing, and interprofessional groups. This study applied an explanatory sequential mixed methods design. The quantitative phase involved observation of the learning process in PBL tutorial with checklists to code students' performance of learning behaviour, ethics discussion skills, learning content explored, and analysis through comparison of accumulative percentage of the coded performance between groups. Content analysis of post-PBL homework self-reflections from interprofessional group was conducted as the following explanatory qualitative phase. Quantitative results indicated that nursing students performed favourably on course engagement, caring, and communication while medical students performed positively on issue identification and the life science aspect. Interprofessional group showed the strength of the both professions and performed best through the learning process. Content analysis revealed that students in the interprofessional group achieved interprofessional learning from recognizing the differences between to appreciating learning from each other and to sense the need of future collaboration. With early exposure to IPE, undergraduate students may learn to balance their socialized viewpoints by seeing ethical dilemmas from each other's standpoint. PMID:27152541

  13. Atmospheric Deposition: Sampling Procedures, Analytical Methods, and Main Recent Findings from the Scientific Literature

    M. Amodio

    2014-01-01

    Full Text Available The atmosphere is a carrier on which some natural and anthropogenic organic and inorganic chemicals are transported, and the wet and dry deposition events are the most important processes that remove those chemicals, depositing it on soil and water. A wide variety of different collectors were tested to evaluate site-specificity, seasonality and daily variability of settleable particle concentrations. Deposition fluxes of POPs showed spatial and seasonal variations, diagnostic ratios of PAHs on deposited particles, allowed the discrimination between pyrolytic or petrogenic sources. Congener pattern analysis and bulk deposition fluxes in rural sites confirmed long-range atmospheric transport of PCDDs/Fs. More and more sophisticated and newly designed deposition samplers have being used for characterization of deposited mercury, demonstrating the importance of rain scavenging and the relatively higher magnitude of Hg deposition from Chinese anthropogenic sources. Recently biological monitors demonstrated that PAH concentrations in lichens were comparable with concentrations measured in a conventional active sampler in an outdoor environment. In this review the authors explore the methodological approaches used for the assessment of atmospheric deposition, from the analysis of the sampling methods, the analytical procedures for chemical characterization of pollutants and the main results from the scientific literature.

  14. An efficient method to find potentially universal population genetic markers, applied to metazoans

    Chenuil Anne

    2010-09-01

    Full Text Available Abstract Background Despite the impressive growth of sequence databases, the limited availability of nuclear markers that are sufficiently polymorphic for population genetics and phylogeography and applicable across various phyla restricts many potential studies, particularly in non-model organisms. Numerous introns have invariant positions among kingdoms, providing a potential source for such markers. Unfortunately, most of the few known EPIC (Exon Primed Intron Crossing loci are restricted to vertebrates or belong to multigenic families. Results In order to develop markers with broad applicability, we designed a bioinformatic approach aimed at avoiding multigenic families while identifying intron positions conserved across metazoan phyla. We developed a program facilitating the identification of EPIC loci which allowed slight variation in intron position. From the Homolens databases we selected 29 gene families which contained 52 promising introns for which we designed 93 primer pairs. PCR tests were performed on several ascidians, echinoderms, bivalves and cnidarians. On average, 24 different introns per genus were amplified in bilaterians. Remarkably, five of the introns successfully amplified in all of the metazoan genera tested (a dozen genera, including cnidarians. The influence of several factors on amplification success was investigated. Success rate was not related to the phylogenetic relatedness of a taxon to the groups that most influenced primer design, showing that these EPIC markers are extremely conserved in animals. Conclusions Our new method now makes it possible to (i rapidly isolate a set of EPIC markers for any phylum, even outside the animal kingdom, and thus, (ii compare genetic diversity at potentially homologous polymorphic loci between divergent taxa.

  15. Healthy bread initiative: methods, findings, and theories--Isfahan Healthy Heart Program.

    Talaei, Mohammad; Mohammadifard, Noushin; Khaje, Mohammad-Reza; Sarrafzadegan, Nizal; Sajjadi, Firoozeh; Alikhasi, Hasan; Maghroun, Maryam; Iraji, Farhad; Ehteshami, Shahram

    2013-03-01

    The scientific evidences show that the content, baking methods, and types of bread can make health impacts. Bread, as a major part of Iranian diet, demonstrates a significant potential to be targeted as health promotion subject. Healthy Food for Healthy Communities (HFHC) was a project of Isfahan Healthy Heart Program (IHHP), consisting of a wide variety of strategies, like Healthy Bread (HB) Initiative. The HB Initiative was designed to improve the behaviour of both producers and consumers, mainly aiming at making high-fibre, low-salt bread, eliminating the use of baking soda, providing enough rest time for dough before baking (at least one hour), and enough baking time (at least one minute in oven). A workshop was held for volunteer bakers, and a baker-to-baker training protocol under direct supervision was designed for future volunteers. Cereal Organization was persuaded to provide less refined flour that contained more bran. Health messages in support of new breads were disseminated by media and at bakeries by health professionals. Evaluation of the HB Initiative was done using before-after assessments and population surveys. While HB was baked in 1 (0.01%) bakery at baseline, 402 (41%) bakeries in the intervention area joined the HB Initiative in 2009. Soda was completely eliminated and fibre significantly increased from 4 +/- 0.4 g% before study to 12 +/- 0.6 g% after the intervention (p bread decreased from 13 +/- 1.8 g% to 2 +/- 0.5 g% and was expressed as the most important advantage of this initiative by consumers. People who lived in Isfahan city consumed whole bread 6 times more than those who lived in reference area Arak (p breads as a healthy choice that were compatible with local dishes and made a model to solve the longstanding problems of bread. It used various health promotion approaches but was best consistent with Beattie's model. PMID:23617204

  16. A Novel Approach Based on MEMS-Gyro's Data Deep Coupling for Determining the Centroid of Star Spot

    Xing Fei

    2012-01-01

    Full Text Available The traditional approach of star tracker for determining the centroid of spot requires enough energy and good shape, so a relatively long exposure time and stable three-axis state become necessary conditions to maintain high accuracy, these limit its update rate and dynamic performance. In view of these issues, this paper presents an approach for determining the centroid of star spot which based on MEMS-Gyro's data deep coupling, it achieves the deep fusion of the data of star tracker and MEMS-Gyro at star map level through the introduction of EKF. The trajectory predicted by using the angular velocity of three axes can be used to set the extraction window, this enhances the dynamic performance because of the accurate extraction when the satellite has angular speed. The optimal estimations of the centroid position and the drift in the output signal of MEMS-Gyro through this approach reduce the influence of noise of the detector on accuracy of the traditional approach for determining the centroid and effectively correct the output signal of MEMS-Gyro. At the end of this paper, feasibility of this approach is verified by simulation.

  17. Digital animation as a method to disseminate research findings to the community using a community-based participatory approach.

    Vaughn, Nicole A; Jacoby, Sara F; Williams, Thalia; Guerra, Terry; Thomas, Nicole A; Richmond, Therese S

    2013-03-01

    Community-based participatory research (CBPR) has garnered increasing interest over the previous two decades as researchers have tackled increasingly complex health problems. In academia, professional presentations and articles are major ways that research is disseminated. However, dissemination of research findings to the people and communities who participated in the research is many times forgotten. In addition, little scholarly literature is focused on creative dissemination of research findings to the community using CBPR methods. We seek to fill this gap in the literature by providing an exemplar of research dissemination and partnership strategies that were used to complete this project. In this paper, we present a novel approach to the dissemination of research findings to our targeted communities through digital animation. We also provide the foundational thinking and specific steps that were taken to select this specific dissemination product development and distribution strategy. PMID:22395365

  18. 一种改进的基于质心的文本分类算法%AN IMPROVED TEXT CATEGORISATION ALGORITHM BASED ON CENTROID

    陈震; 吴斌; 沈崇玮; 张忠辉; 王柏

    2013-01-01

    Text categorisation is a hot topic in data mining and information retrieval, and has been rapidly developing in recent years. Centroid-based approach is a text categorisation method modelling fast and having good effect, many researchers have studied this method thoroughly and put forward the improvement strategies to incessantly raise the performance of it. In this paper, we propose a novel algorithm to dynamically adjust the centroid position. The algorithm adjusts the centroid position dynamically based on every sample text in training set. Besides, we tackle the bottleneck aiming at mass data, make use of two current parallel computing frameworks, MapReduce and BSP, and put forward the parallel strategy of the algorithm. By the comparative experiments on 5 different datasets with other algorithms, we prove that the algorithm has quite accurate classification effect.%文本分类是数据挖掘与信息检索领域的热点话题,近年来迅速发展.基于质心的方法是一种建模迅速且效果较好的文本分类方法,许多学者对该方法进行了深入研究并提出改进策略,不断提高算法效果.提出一种新的动态调整质心位置算法,该算法根据训练集中的每个样本文本动态的调整质心位置.并且针对海量数据处理瓶颈,运用当前两种并行计算框架MapReduce和BSP,提出了算法的并行策略.通过与其它算法在5种不同数据集中的对比实验,证明该方法确有较准确的分类效果.

  19. SEQUENTIAL AND PARALLEL ALGORITHM TO FIND MAXIMUM FLOW ON EXTENDED MIXED NETWORKS BY REVISED POSTFLOW-PULL METHODS

    Lau Nguyen Dinh

    2016-01-01

    Full Text Available The problem of finding maximum flow in network graph is extremely interesting and practically applicable in many fields in our daily life, especially in transportation. Therefore, a lot of researchers have been studying this problem in various methods. Especially in 2013, we has developed a new algorithm namely, postflow-pull algorithm to find the maximum flow on traditional networks. In this paper, we revised postflow-push methods to solve this problem of finding maximum flow on extended mixed network. In addition, to take more advantage of multi-core architecture of the parallel computing system, we build this parallel algorithm. This is a completely new method not being announced in the world. The results of this paper are basically systematized and proven. The idea of this algorithm is using multi processors to work in parallel by postflow_push algorithm. Among these processors, there is one main processor managing data, sending data to the sub processors, receiving data from the sub-processors. The sub-processors simultaneously execute their work and send their data to the main processor until the job is finished, the main processor will show the results of the problem.

  20. The Shortlist Method for fast computation of the Earth Mover's Distance and finding optimal solutions to transportation problems.

    Gottschlich, Carsten; Schuhmacher, Dominic

    2014-01-01

    Finding solutions to the classical transportation problem is of great importance, since this optimization problem arises in many engineering and computer science applications. Especially the Earth Mover's Distance is used in a plethora of applications ranging from content-based image retrieval, shape matching, fingerprint recognition, object tracking and phishing web page detection to computing color differences in linguistics and biology. Our starting point is the well-known revised simplex algorithm, which iteratively improves a feasible solution to optimality. The Shortlist Method that we propose substantially reduces the number of candidates inspected for improving the solution, while at the same time balancing the number of pivots required. Tests on simulated benchmarks demonstrate a considerable reduction in computation time for the new method as compared to the usual revised simplex algorithm implemented with state-of-the-art initialization and pivot strategies. As a consequence, the Shortlist Method facilitates the computation of large scale transportation problems in viable time. In addition we describe a novel method for finding an initial feasible solution which we coin Modified Russell's Method. PMID:25310106

  1. Neutron radiography with sub-15 μm resolution through event centroiding

    Conversion of thermal and cold neutrons into a strong ∼1 ns electron pulse with an absolute neutron detection efficiency as high as 50–70% makes detectors with 10B-doped Microchannel Plates (MCPs) very attractive for neutron radiography and microtomography applications. The subsequent signal amplification preserves the location of the event within the MCP pore (typically 6–10 μm in diameter), providing the possibility to perform neutron counting with high spatial resolution. Different event centroiding techniques of the charge landing on a patterned anode enable accurate reconstruction of the neutron position, provided the charge footprints do not overlap within the time required for event processing. The new fast 2×2 Timepix readout with >1.2 kHz frame rates provides the unique possibility to detect neutrons with sub-15 μm resolution at several MHz/cm2 counting rates. The results of high resolution neutron radiography experiments presented in this paper, demonstrate the sub-15 μm resolution capability of our detection system. The high degree of collimation and cold spectrum of ICON and BOA beamlines combined with the high spatial resolution and detection efficiency of MCP-Timepix detectors are crucial for high contrast neutron radiography and microtomography with high spatial resolution. The next generation of Timepix electronics with sparsified readout should enable counting rates in excess of 107 n/cm2/s taking full advantage of high beam intensity of present brightest neutron imaging facilities.

  2. Power centroid radar and its rise from the universal cybernetics duality

    Feria, Erlan H.

    2014-05-01

    Power centroid radar (PC-Radar) is a fast and powerful adaptive radar scheme that naturally surfaced from the recent discovery of the time-dual for information theory which has been named "latency theory." Latency theory itself was born from the universal cybernetics duality (UC-Duality), first identified in the late 1970s, that has also delivered a time dual for thermodynamics that has been named "lingerdynamics" and anchors an emerging lifespan theory for biological systems. In this paper the rise of PC-Radar from the UC-Duality is described. The development of PC-Radar, US patented, started with Defense Advanced Research Projects Agency (DARPA) funded research on knowledge-aided (KA) adaptive radar of the last decade. The outstanding signal to interference plus noise ratio (SINR) performance of PC-Radar under severely taxing environmental disturbances will be established. More specifically, it will be seen that the SINR performance of PC-Radar, either KA or knowledgeunaided (KU), approximates that of an optimum KA radar scheme. The explanation for this remarkable result is that PC-Radar inherently arises from the UC-Duality, which advances a "first principles" duality guidance theory for the derivation of synergistic storage-space/computational-time compression solutions. Real-world synthetic aperture radar (SAR) images will be used as prior-knowledge to illustrate these results.

  3. The dynamical climate network, its major centroids, and their close relation to the ENSO cycle

    Gozolchiani, Avi; Yamasaki, Kazuko; Berezin, Yehiel; Guez, Oded; Dijkstra, Henk; Havlin, Shlomo

    2013-04-01

    The observed relations between temperature fluctuations in different geographical regions yields a very robust climate network pattern that remains highly stable during time. Here, we break up the different elements that contribute to this stability, and quantify them [Y. Berezin, et. al., Nat. Sci. Rep. (2012)]. Due to its high stability, the climate network adjacency matrix can be regarded as a spatial field on its own right, and its typical profiles indeed have been the topic of recent studies. We have demonstrated [K. Yamasaki et. al. PRL (2008),A. Gozolchiani et. al. EPL (2008)] that during El-Nino times large portions of this field have a reduced value, corresponding to a less correlated atmosphere. We are now able to pinpoint a peculiar and rich pattern in this effect - the unique autonomous component in the eastern pacific [A. Gozolchiani et. al. PRL 107, 148501 (2011)]. In contrast to our and others earlier works, the different stages of the ENSO cycle come out as the 2 dominant K-means centroids, without pre-identification based on ENSO indices. Finally, the different feedback mechanisms which contribute to events are shown to be reflected in the network profile.

  4. Rapid Centroids and the Refined Position Accuracy of the Swift Gamma-ray Burst Catalogue

    The Swift X-ray Telescope autonomously refines the Burst Alert Telescope positions (∼1-4' uncertainty) to better than 5 arcsec, within 5 seconds of target acquisition by the observatory for typical bursts. The results of the rapid positioning capability of the XRT are presented here for both known sources and newly discovered GRBs, demonstrating the ability to automatically utilise one of two integration times according to the burst brightness, and to correct the position for alignment offsets caused by the fast pointing performance and variable thermal environment of the satellite as measured by the Telescope Alignment Monitor. We present an evaluation of the position accuracy for both the onboard centroiding software and the ground software for the calibration targets and show that a significant improvement in position accuracy is obtained if the boresight detector position is optimised relative to the spacecraft pointing. Finally, we present an updated catalogue of Swift GRB X-ray positions obtained in Photon Counting Mode using the improved, calibrated boresight

  5. New Distributed Positioning Algorithm Based on Centroid of Circular Belt for Wireless Sensor Networks

    Xu-Zhi Lai; Simon X. Yang; Gui-Xiu Zeng; Jin-Hua She; Min Wu

    2007-01-01

    This paper presents a new distributed positioning algorithm for unknown nodes in a wireless sensor network. The algorithm is based exclusively on connectivity. First, assuming that the positions of the anchor nodes are already known, a circular belt containing an unknown node is obtained using information about the anchor nodes that are in radio range of the unknown node, based on the geometric relationships and communication constraints among the unknown node and the anchor nodes. Then, the centroid of the circular belt is taken to be the estimated position of the unknown node. Since the algorithm is very simple and since the only communication needed is between the anchor nodes and the unknown node, the communication and computational loads are very small. Furthermore, the algorithm is robust because neither the failure of old unknown nodes nor the addition of new unknown nodes influences the positioning of unknown nodes to be located. A theoretical analysis and simulation results show that the algorithm does not produce any cumulative error and is insensitive to range error, and that a change in the number of sensor nodes does not affect the communication or computational load. These features make this algorithm suitable for all sizes of low-power wireless sensor networks.

  6. Solving the Task of Finding the Meaning of Dreams as a Method of Exploring Comprehension of Meanings of Life

    Kubarev V.S.

    2015-10-01

    Full Text Available The paper presents outcomes of a quantitative psychotechnological research on the process of one's comprehension of his/her own life. It focuses on the reflective mechanisms of realizing meanings of life, thus further developing research on meaning formations of personality within the culturalactivity approach. For these purposes a method of solving the task of finding the meaning of a dream was used in the study, which is in fact an operationalization of the method of productive amplification of consciousness. Rather than examining the already formed contents of meanings of life available for introspective descriptions, this method allows the exploration of the constructive activity of consciousness through which these meanings of life are formed. The main outcome is the reconstruction and empirical model of reflective activity carried out by the individual in the process of comprehending meanings of life and his/her life situation

  7. 基于加权聚类质心的 SVM 不平衡分类方法%Support vector machine imbalanced data classification based on weighted clustering centroid

    2013-01-01

    Classification of imbalanced data has become a research hot topic in machine learning .Traditional classi-fication algorithms assume that different classes have balanced distribution or equal misclassification cost , thus, making it hard to get ideal result of classifications .A support vector machine (SVM) classification method based on weighted clustering centroid was proposed in this paper .First, unsupervised clustering was applied to the positive and negative samples respectively to extract the clustering centroid of each clustering , which was represented the most in compactness of the clustering sample .Next, all clustering centroids formed a new set of balance training .In order to minimize the information loss during clustering , each clustering centroid was associated with a weight factor that was defined proportional to the number of samples of the class .Finally, all clustering centroids and weight fac-tors participated in the training of the improved SVM model .Experimental results show that the proposed method can make the sample selected from model train sets more typical and improve the classification performance better than other sampling techniques for dealing with imbalanced data .%  不平衡数据分类是机器学习研究的热点问题,传统分类算法假定不同类别具有平衡分布或误分代价相同,难以得到理想的分类结果。提出一种基于加权聚类质心的SVM分类方法,在正负类样本上分别进行聚类,对每个聚类,用聚类质心和权重因子代表聚类内样本分布和数量,相等类别数量的质心和权重因子参与SVM模型训练。实验结果表明,该方法使模型的训练样本具有较高的代表性,分类性能与其他采样方法相比得到了提升。

  8. Quantum size correction to the work function and the centroid of excess charge in positively ionized simple metal clusters

    M. Payami

    2003-12-01

    Full Text Available  In this work, we have shown the important role of the finite-size correction to the work function in predicting the correct position of the centroid of excess charge in positively charged simple metal clusters with different values . For this purpose, firstly we have calculated the self-consistent Kohn-Sham energies of neutral and singly-ionized clusters with sizes in the framework of local spin-density approximation and stabilized jellium model (SJM as well as simple jellium model (JM with rigid jellium. Secondly, we have fitted our results to the asymptotic ionization formulas both with and without the size correction to the work function. The results of fittings show that the formula containing the size correction predict a correct position of the centroid inside the jellium while the other predicts a false position, outside the jellium sphere.

  9. Low-Frequency Centroid Moment Tensor Inversion of the 2015 Illapel Earthquake from Superconducting-Gravimeter Data

    Zábranová, Eliška; Matyska, Ctirad

    2016-04-01

    After the 2015 Illapel earthquake the radial and spheroidal modes up to 1 mHz were registered by the network of superconducting gravimeters. These data provide unique opportunity to obtain ultralow-frequency estimates of several centroid moment tensor components. We employ the superconducting-gravimeter records of 60-h lengths and perform the joint inversion for M_{rr}, (M_{\\vartheta \\vartheta }-M_{\\varphi \\varphi })/2 and M_{\\vartheta \\varphi } centroid moment tensor components from spheroidal modes up to 1 mHz. The M_{rr} component is also obtained from independent inversion of the radial modes _0S_0 and _1S_0. Our results are consistent with the published solutions obtained from higher frequency data, suggesting thus negligible slow afterslip phenomenon.

  10. Temnothoraxcrasecundus sp. n. - a cryptic Eurocaucasian ant species (Hymenoptera, Formicidae) discovered by Nest Centroid Clustering.

    Seifert, Bernhard; Csösz, Sandor

    2015-01-01

    The paper integrates two independent studies of numeric morphology-based alpha-taxonomy of the cryptic ant species Temnothoraxcrassispinus (Karavajev, 1926) and Temnothoraxcrasecundus sp. n. conducted by different investigators, using different equipment, considering different character combinations and evaluating different samples. Samples investigated included 603 individual workers from 203 nests - thereof 104 nest samples measured by Seifert and 99 by Csösz. The material originated from Europe, Asia Minor and Caucasia. There was a very strong interspecific overlap in any of the 29 shape characters recorded and subjective expert determination failed in many cases. Primary classification hypotheses were formed by the exploratory data analysis Nest Centroid (NC) clustering and corrected to final species hypotheses by an iterative linear discriminant analysis algorithm. The evaluation of Seifert's and Csösz's data sets arrived at fully congruent conclusions. NC-Ward and NC-K-means clustering disagreed from the final species hypothesis in only 1.9 and 1.9% of the samples in Seifert's data set and by 1.1 and 2.1% in Csösz's data set which is a strong argument for heterospecificity. The type series of Temnothoraxcrassispinus and Temnothoraxcrasecundus sp. n. were allocated to different clusters with p = 0.9851 and p = 0.9912 respectively. The type series of the junior synonym Temnothoraxslavonicus (Seifert, 1995) was allocated to the Temnothoraxcrassispinus cluster with p = 0.9927. Temnothoraxcrasecundus sp. n. and Temnothoraxcrassispinus are parapatric species with a long contact zone stretching from the Peloponnisos peninsula across Bulgaria northeast to the southern Ukraine. There is no indication for occurrence of interspecifically mixed nests or intraspecific polymorphism. However, a significant reduction of interspecific morphological distance at sites with syntopic occurrence of both species indicates local hybridization. The results are discussed within the

  11. Centroid and Envelope Eynamics of Charged Particle Beams in an Oscillating Wobbler and External Focusing Lattice for Heavy Ion Fusion Applications

    Recent heavy ion fusion target studies show that it is possible to achieve ignition with direct drive and energy gain larger than 100 at 1MJ. To realize these advanced, high-gain schemes based on direct drive, it is necessary to develop a reliable beam smoothing technique to mitigate instabilities and facilitate uniform deposition on the target. The dynamics of the beam centroid can be explored as a possible beam smoothing technique to achieve a uniform illumination over a suitably chosen region of the target. The basic idea of this technique is to induce an oscillatory motion of the centroid for each transverse slice of the beam in such a way that the centroids of different slices strike different locations on the target. The centroid dynamics is controlled by a set of biased electrical plates called 'wobblers'. Using a model based on moments of the Vlasov-Maxwell equations, we show that the wobbler deflection force acts only on the centroid motion, and that the envelope dynamics are independent of the wobbler fields. If the conducting wall is far away from the beam, then the envelope dynamics and centroid dynamics are completely decoupled. This is a preferred situation for the beam wobbling technique, because the wobbler system can be designed to generate the desired centroid motion on the target without considering its effects on the envelope and emittance. A conceptual design of the wobbler system for a heavy ion fusion driver is briefly summarized.

  12. Optimization of Phenolic Antioxidant Extraction from Wuweizi (Schisandra chinensis) Pulp Using Random-Centroid Optimazation Methodology

    Xiong (Bill) Yu; Hao Jing; Xia Wu

    2011-01-01

    The extraction optimization and composition analysis of polyphenols in the fresh pulp of Wuweizi (Schisandra chinensis) have been investigated in this study. The extraction process of polyphenols from Wuweizi pulp was optimized using Random-Centroid Optimization (RCO) methodology. Six factors including liquid and solid ratio, ethanol concentration, pH, temperature, heating time and extraction times, and three extraction targets of polyphenol content, antioxidant activity and extract yield wer...

  13. Energy Method of Finding Distribution Constants of an Antiferromagnetic Vector for an Antidot System in a Two-sublattice Antiferromagnet

    V.V. Kulish

    2015-06-01

    Full Text Available The paper investigates the antiferromagnetic vector distribution in an antiferromagnetic film with a system of antidots. A static distribution of the antiferromagnetic vector is written and a method – based on the minimization of the antiferromagnet energy – that allows reducing the number of boundary conditions required for finding the constants of this distribution is proposed. Equations for the distribution constants are obtained for the both cases of minimizing the antiferromagnet energy by one and by two distribution constants that enter the expression for the antiferromagnet energy. The method is illustrated on a system of one isolated antidot. For such system, one additional condition – for the case when two boundary conditions on the surface of the antidot are given – and two additional conditions – for the case when one boundary condition on the surface of the antidot is given – on the distribution constants are written.

  14. Meeting report: discussions and preliminary findings on extracellular RNA measurement methods from laboratories in the NIH Extracellular RNA Communication Consortium

    Louise C. Laurent

    2015-08-01

    Full Text Available Extracellular RNAs (exRNAs have been identified in all tested biofluids and have been associated with a variety of extracellular vesicles, ribonucleoprotein complexes and lipoprotein complexes. Much of the interest in exRNAs lies in the fact that they may serve as signalling molecules between cells, their potential to serve as biomarkers for prediction and diagnosis of disease and the possibility that exRNAs or the extracellular particles that carry them might be used for therapeutic purposes. Among the most significant bottlenecks to progress in this field is the lack of robust and standardized methods for collection and processing of biofluids, separation of different types of exRNA-containing particles and isolation and analysis of exRNAs. The Sample and Assay Standards Working Group of the Extracellular RNA Communication Consortium is a group of laboratories funded by the U.S. National Institutes of Health to develop such methods. In our first joint endeavour, we held a series of conference calls and in-person meetings to survey the methods used among our members, placed them in the context of the current literature and used our findings to identify areas in which the identification of robust methodologies would promote rapid advancements in the exRNA field.

  15. Are human service agencies ready for disasters? Findings from a mixed-methods needs assessment and planning project.

    Hipper, Thomas J; Orr, Ashley; Chernak, Esther

    2015-01-01

    A mixed-methods design was used to assess the current capacity of human service agencies to provide services in a major disaster, identify challenges and successful strategies for providing those services, and formulate specific recommendations for government planners and the nonprofit sector to promote the integration of human service agencies into emergency preparedness and response. A web-based survey was completed by 188 unique human service agencies, 31 semistructured interviews were conducted with human service agency and government leaders from southeastern Pennsylvania and the mid-Atlantic region, and a collaborative planning meeting was held to review the findings and develop systems-based recommendations. Survey results indicated that human service agencies serve the most vulnerable communities during disasters and would welcome integration into preparedness and response plans, but they currently face challenges that include a lack of real-time communication and opportunities for collaborative planning with government partners. Interview findings were grouped according to 5 themes that emerged: capacity, coordination, communication, training, and leadership. This study identified recommendations to assist human service agencies, local health departments, and emergency management agencies as they work to ensure that needed human services are available during disasters, despite the resource challenges that most agencies face. PMID:25813974

  16. The centroid shift of the 5d levels of Ce sup 3 sup + with respect to the 4f levels in ionic crystals, a theoretical investigation

    Andriessen, J; Eijk, C W E

    2002-01-01

    The centroid shifts of the 5d level of Ce sup 3 sup + in BaF sub 2 , LaAlO sub 3 and LaCl sub 3 have been calculated using the ionic cluster approach. By applying configuration interaction as extension of the basic HF-LCAO approach the dynamical polarization contribution to the centroid shift was calculated. This was found to be only successful if basis sets are used optimized for polarization of the anions.

  17. Using quantitative and qualitative data in health services research – what happens when mixed method findings conflict? [ISRCTN61522618

    Howel Denise

    2006-03-01

    Full Text Available Abstract Background In this methodological paper we document the interpretation of a mixed methods study and outline an approach to dealing with apparent discrepancies between qualitative and quantitative research data in a pilot study evaluating whether welfare rights advice has an impact on health and social outcomes among a population aged 60 and over. Methods Quantitative and qualitative data were collected contemporaneously. Quantitative data were collected from 126 men and women aged over 60 within a randomised controlled trial. Participants received a full welfare benefits assessment which successfully identified additional financial and non-financial resources for 60% of them. A range of demographic, health and social outcome measures were assessed at baseline, 6, 12 and 24 month follow up. Qualitative data were collected from a sub-sample of 25 participants purposively selected to take part in individual interviews to examine the perceived impact of welfare rights advice. Results Separate analysis of the quantitative and qualitative data revealed discrepant findings. The quantitative data showed little evidence of significant differences of a size that would be of practical or clinical interest, suggesting that the intervention had no impact on these outcome measures. The qualitative data suggested wide-ranging impacts, indicating that the intervention had a positive effect. Six ways of further exploring these data were considered: (i treating the methods as fundamentally different; (ii exploring the methodological rigour of each component; (iii exploring dataset comparability; (iv collecting further data and making further comparisons; (v exploring the process of the intervention; and (vi exploring whether the outcomes of the two components match. Conclusion The study demonstrates how using mixed methods can lead to different and sometimes conflicting accounts and, using this six step approach, how such discrepancies can be harnessed

  18. Finding possible transition states of defects in silicon-carbide and alpha-iron using the dimer method

    Energetic primary recoil atoms from ion implantation or fast neutron irradiation produce isolated point defects and clusters of both vacancies and interstitials. The migration energies and mechanisms for these defects are crucial to successful multiscale modeling of microstructural evolution during ion-implantation, thermal annealing, or under irradiation over long periods of time. The dimer method is employed to search for possible transition states of interstitials and small interstitial clusters in SiC and α-Fe. The method uses only the first derivatives of the potential energy to find saddle points without knowledge of the final state of the transition. In SiC, the possible migration pathway for the C interstitial is found to consist of the first neighbor jump via a Si site or second neighbor jump, but the relative probability for the second neighbor jump is very low. In α-Fe, the possible transition states are studied as a function of interstitial cluster size, and the lowest energy barriers correspond to defect migration along directions. However, this paper addresses whether migrating interstitial clusters can thermally change their direction, and the activation energies and corresponding mechanisms for changing the direction of these clusters are determined

  19. Finding possible transition states of defects in silicon-carbide and alpha-iron using the dimer method

    Gao Fei; Weber, W J; Corrales, L R; Jonsson, H

    2003-01-01

    Energetic primary recoil atoms from ion implantation or fast neutron irradiation produce isolated point defects and clusters of both vacancies and interstitials. The migration energies and mechanisms for these defects are crucial to successful multiscale modeling of microstructural evolution during ion-implantation, thermal annealing, or under irradiation over long periods of time. The dimer method is employed to search for possible transition states of interstitials and small interstitial clusters in SiC and alpha-Fe. The method uses only the first derivatives of the potential energy to find saddle points without knowledge of the final state of the transition. In SiC, the possible migration pathway for the C interstitial is found to consist of the first neighbor jump via a Si site or second neighbor jump, but the relative probability for the second neighbor jump is very low. In alpha-Fe, the possible transition states are studied as a function of interstitial cluster size, and the lowest energy barriers corr...

  20. Radiation organ doses received in a nationwide cohort of U.S. radiologic technologists: methods and findings.

    Simon, Steven L; Preston, Dale L; Linet, Martha S; Miller, Jeremy S; Sigurdson, Alice J; Alexander, Bruce H; Kwon, Deukwoo; Yoder, R Craig; Bhatti, Parveen; Little, Mark P; Rajaraman, Preetha; Melo, Dunstana; Drozdovitch, Vladimir; Weinstock, Robert M; Doody, Michele M

    2014-11-01

    In this article, we describe recent methodological enhancements and findings from the dose reconstruction component of a study of health risks among U.S. radiologic technologists. An earlier version of the dosimetry published in 2006 used physical and statistical models, literature-reported exposure measurements for the years before 1960, and archival personnel monitoring badge data from cohort members through 1984. The data and models previously described were used to estimate annual occupational radiation doses for 90,000 radiological technologists, incorporating information about each individual's employment practices based on a baseline survey conducted in the mid-1980s. The dosimetry methods presented here, while using many of the same methods as before, now estimate 2.23 million annual badge doses (personal dose equivalent) for the years 1916-1997 for 110,374 technologists, but with numerous methodological improvements. Every technologist's annual dose is estimated as a probability density function to reflect uncertainty about the true dose. Multiple realizations of the entire cohort distribution were derived to account for shared uncertainties and possible biases in the input data and assumptions used. Major improvements in the dosimetry methods from the earlier version include: A substantial increase in the number of cohort member annual badge dose measurements; Additional information on individual apron usage obtained from surveys conducted in the mid-1990s and mid-2000s; Refined modeling to develop lognormal annual badge dose probability density functions using censored data regression models; Refinements of cohort-based annual badge probability density functions to reflect individual work patterns and practices reported on questionnaires and to more accurately assess minimum detection limits; and Extensive refinements in organ dose conversion coefficients to account for uncertainties in radiographic machine settings for the radiographic techniques

  1. Method for finding metabolic properties based on the general growth law. Liver examples. A general framework for biological modeling.

    Yuri K Shestopaloff

    Full Text Available We propose a method for finding metabolic parameters of cells, organs and whole organisms, which is based on the earlier discovered general growth law. Based on the obtained results and analysis of available biological models, we propose a general framework for modeling biological phenomena and discuss how it can be used in Virtual Liver Network project. The foundational idea of the study is that growth of cells, organs, systems and whole organisms, besides biomolecular machinery, is influenced by biophysical mechanisms acting at different scale levels. In particular, the general growth law uniquely defines distribution of nutritional resources between maintenance needs and biomass synthesis at each phase of growth and at each scale level. We exemplify the approach considering metabolic properties of growing human and dog livers and liver transplants. A procedure for verification of obtained results has been introduced too. We found that two examined dogs have high metabolic rates consuming about 0.62 and 1 gram of nutrients per cubic centimeter of liver per day, and verified this using the proposed verification procedure. We also evaluated consumption rate of nutrients in human livers, determining it to be about 0.088 gram of nutrients per cubic centimeter of liver per day for males, and about 0.098 for females. This noticeable difference can be explained by evolutionary development, which required females to have greater liver processing capacity to support pregnancy. We also found how much nutrients go to biomass synthesis and maintenance at each phase of liver and liver transplant growth. Obtained results demonstrate that the proposed approach can be used for finding metabolic characteristics of cells, organs, and whole organisms, which can further serve as important inputs and constraints for many applications in biology (such as protein expression, biotechnology (synthesis of substances, and medicine.

  2. Mixed methods evaluation of targeted case finding for cardiovascular disease prevention using a stepped wedged cluster RCT

    Marshall Tom

    2012-10-01

    Full Text Available Abstract Background A pilot project cardiovascular prevention was implemented in Sandwell (West Midlands, UK. This used electronic primary care records to identify untreated patients at high risk of cardiovascular disease then invited these high risk patients for assessment by a nurse in their own general practice. Those found to be eligible for treatment were offered treatment. During the pilot a higher proportion of high risk patients were started on treatment in the intervention practices than in control practices. Following the apparent success of the prevention project, it was intended to extend the service to all practices across the Sandwell area. However the pilot project was not a robust evaluation. There was a need for an efficient evaluation that would not disrupt the planned rollout of the project. Methods/design Project nurses will sequentially implement targeted cardiovascular case finding in a phased way across all general practices, with the sequence of general practices determined randomly. This is a stepped wedge randomised controlled trial design. The target population is patients aged 35 to 74, without diabetes or cardiovascular disease whose ten-year cardiovascular risk, (determined from data in their electronic records is ≥20%. The primary outcome is the number of high risk patients started on treatment, because these data could be efficiently obtained from electronic primary care records. From this we can determine the effects of the case finding programme on the proportion of high risk patients started on treatment in practices before and after implementation of targeted case finding. Cost-effectiveness will be modelled from the predicted effects of treatments on cardiovascular events and associated health service costs. Alongside the implementation it is intended to interview clinical staff and patients who participated in the programme in order to determine acceptability to patients and clinicians. Practical

  3. Some Companion Inequalities Related to Centroidal Mean%形心平均的双边不等式

    高红亚; 李梦华

    2012-01-01

    一些经典不等式及其双边关系式在数学、物理学和工程技术中有着广泛应用.考虑形心平均与其他几个经典平均,得到几个双边不等式.%Some classical inequalities and their companion relations have wide applicatoins in mathematics, physics and engineering. Centroidal mean and some other classical means are considered. Some companion inequalities are obtained.

  4. Pseudometrically Constrained Centroidal Voronoi Tessellations: Generating uniform antipodally symmetric points on the unit sphere with a novel acceleration strategy and its applications to Diffusion and 3D radial MRI

    Koay, Cheng Guan

    2012-01-01

    Purpose: The purpose of this work is to investigate the hypothesis that uniform sampling measurements that are endowed with antipodal symmetry play an important role when the raw data and image data are related through the Fourier relationship as in q-space diffusion MRI and 3D radial MRI. Currently, it is extremely challenging to generate large uniform antipodally symmetric point sets suitable for 3D radial MRI. A novel approach is proposed to solve this important and long-standing problem. Methods: The proposed method is based upon constrained centroidal Voronoi tessellations of the upper hemisphere with a novel pseudometric. Geometrically intuitive approach to tessellating the upper hemisphere is also proposed. Results: The average time complexity of the proposed centroidal tessellations was shown to be effectively on the order of the product of the number of iterations and the number of generators. For small sample size, the proposed method was comparable to the state-of-the-art iterative method in terms ...

  5. Essential features influencing collaboration in team-based non-specific back pain rehabilitation: Findings from a mixed methods study.

    Hellman, Therese; Jensen, Irene; Bergström, Gunnar; Brämberg, Elisabeth Björk

    2016-05-01

    The aim of the study presented in this article was to explore how professionals, without guidelines for implementing interprofessional teamwork, experience the collaboration within team-based rehabilitation for people with back pain and how this collaboration influences their clinical practice. This study employed a mixed methods design. A questionnaire was answered by 383 participants and 17 participants were interviewed. The interviews were analysed using content analysis. The quantitative results showed that the participants were satisfied with their team-based collaboration. Thirty percent reported that staff changes in the past year had influenced their clinical practice, of which 57% reported that these changes had had negative consequences. The qualitative findings revealed that essential features for an effective collaboration were shared basic values and supporting each other. Furthermore, aspects such as having enough time for reflection, staff continuity, and a shared view of the team members' roles were identified as aspects which influenced the clinical practice. Important clinical implications for nurturing and developing a collaboration in team-based rehabilitation are to create shared basic values and a unified view of all team members' roles and their contributions to the team. These aspects need to be emphasised on an ongoing basis and not only when the team is formed. PMID:27152534

  6. Meat intake, cooking methods, dietary carcinogens, and colorectal cancer risk: findings from the Colorectal Cancer Family Registry

    Diets high in red meat and processed meats are established colorectal cancer (CRC) risk factors. However, it is still not well understood what explains this association. We conducted comprehensive analyses of CRC risk and red meat and poultry intakes, taking into account cooking methods, level of doneness, estimated intakes of heterocyclic amines (HCAs) that accumulate during meat cooking, tumor location, and tumor mismatch repair proficiency (MMR) status. We analyzed food frequency and portion size data including a meat cooking module for 3364 CRC cases, 1806 unaffected siblings, 136 unaffected spouses, and 1620 unaffected population-based controls, recruited into the CRC Family Registry. Odds ratios (OR) and 95% confidence intervals (CI) for nutrient density variables were estimated using generalized estimating equations. We found no evidence of an association between total nonprocessed red meat or total processed meat and CRC risk. Our main finding was a positive association with CRC for pan-fried beefsteak (Ptrend < 0.001), which was stronger among MMR deficient cases (heterogeneity P = 0.059). Other worth noting associations, of borderline statistical significance after multiple testing correction, were a positive association between diets high in oven-broiled short ribs or spareribs and CRC risk (Ptrend = 0.002), which was also stronger among MMR-deficient cases, and an inverse association with grilled hamburgers (Ptrend = 0.002). Our results support the role of specific meat types and cooking practices as possible sources of human carcinogens relevant for CRC risk

  7. Effect of point spread functions on star centroid error analysis%点扩散函数对星点提取误差分析的影响

    姜亮; 张宇; 张立国; 张星祥; 任建岳

    2015-01-01

    Star centroid systematic error is called pixel frequency error, whose period is the width of the pixel. The analysis of the distribution of systematic error is useful in error compensation. Point spread function is the main factor which affects the distribution of systematic error. Traditionally the Gauss point spread function is used in the frequency analysis of the systematic error, but its reasonability has not been taken into consideration. With real star image considered, the Giancarlo point spread function was compared with the Gauss point spread function. Then the Giancarlo point spread function was used in the spacial frequency analysis of star centroid systematic error, and the theoretical formulas of the systematic error was obtained. Compared with the result of the traditional frequency analysis, an item that modulated the amplitude of the S curve distribution was added to the theoretical formulas, and that made the x coordinate systematic error distributed as an S curve along x axis and the amplitude of S curve changed along y axis. A simulation under a condition with noise was carried out, and the result was in accordance with the frequency analysis of this article. Finally an experiment is done, the result of the experiment is compensated for according to the theoretical formulas, the star centroid accuracy is improved by 54.42%, which is better than the traditional sine curve fitting compensation method.%星点提取系统误差又称作像元频率误差,它的分布呈现以像元为周期的规律性,分析它的分布规律对补偿这种误差有指导作用.光学系统点扩散函数类型是影响星点提取系统误差分布的主要因素,选取合理的点扩散函数模型对星点提取系统误差进行频域分析,可以减小分析结果与实际的偏离,提高误差补偿效果.传统方法采用Gauss分布点扩散函数模型进行频域分析,但没有考察它的合理性.文中结合星敏感器拍摄的星点像,将一

  8. Aims, methods and preliminary findings of the Physical Activity, Nutrition and Allergies in Children Examined in Athens (PANACEA epidemiological study

    Papadimitriou Anastasios

    2007-07-01

    Full Text Available Abstract Background To determine the prevalence of asthma symptoms in a sample of Greek children aged 10–12 years, and to evaluate these rates in relation to anthropometric, lifestyle characteristics and dietary habits. Methods During 2006, 700 schoolchildren (323 male and 377 female, aged 10–12 years (4th to 6th school grade, were selected from 18 schools located in the greater Athens area. The schools were randomly selected from a list provided by the regional educational offices. To achieve a representative sample the schools enrolled were selected from various region of the Athens area. For each child a questionnaire was completed that was developed for the purposes of the study to retrieve information on: age, sex, school class, other socio-demographic characteristics, anthropometric measurements, dietary habits (through a semi-quantitative Food Frequency Questionnaire and physical activity status; the presence of asthma and allergies was assessed by the standard ISAAC questionnaire. Results The prevalence of wheezing in the past was 25% in boys and 19% in girls, while the prevalence of current wheezing was 9.0% in boys and 5.8% in girls. The prevalence of any asthma symptoms was 27.6% in boys and 20.4% in girls. Multiple logistic regression analysis revealed that increased body weight and sedentary lifestyle is associated with asthma symptoms only in boys. Conclusion The present cross-sectional study cannot establish causal relationships between asthma and increased body weight of schoolchildren; however, our findings underline the associations between asthma, increased body weight, and physical activity at population level, and urge for actions that should be taken by public health policy makers in order to prevent these conditions among children.

  9. Multi-response optimisation of the extraction solvent system for phenolics and antioxidant activities from fermented soy flour using a simplex-centroid design.

    Handa, Cíntia Ladeira; de Lima, Fernando Sanches; Guelfi, Marcela Fernanda Geton; Georgetti, Sandra Regina; Ida, Elza Iouko

    2016-04-15

    A simplex-centroid design comprising three solvents (water, ethanol and methanol) was used to optimise the extraction mixture for phenolics and antioxidant activities from defatted soy flour fermented with Monascus purpureus or Aspergillus oryzae. Total phenolics were more efficiently extracted using only water for both samples. The highest antioxidant activities by the DPPH and ABTS methods were obtained using extraction mixtures containing at least 75 wt% water. Specific water:ethanol:methanol ratios promoted the joint optimisation of the total phenolic and isoflavone contents as well as antioxidant activities: 0.5:0.375:0.125 (wt/wt/wt) and 0.5:0.3:0.2 (wt/wt/wt) from defatted soy flour fermented with M. purpureus or A. oryzae, respectively. However, a water:ethanol ratio of 0.5:0.5 (wt/wt) was deemed optimal because it is comprised of green solvents and yielded results that were greater than 90% of the multi-response maximum values. Both the solvents and the sample matrix strongly influenced the extractability of total phenolics and isoflavones. PMID:26616938

  10. An Example of the Use of Research Methods and Findings as an Experiential Learning Exercise in an Accounting Theory Course

    Bublitz, Bruce; Philipich, Kirk; Blatz, Robert

    2015-01-01

    The purpose of this teaching note is to describe an experiential learning exercise used in a master's level financial accounting theory course. The experiential exercise illustrates how order effects can affect user's judgments, a long-standing research finding. This experiential exercise was used in an attempt to make students more cognizant of…

  11. Optimization of a fermented soy product formulation with a kefir culture and fiber using a simplex-centroid mixture design.

    Baú, Tahis Regina; Garcia, Sandra; Ida, Elza Iouko

    2013-12-01

    The objective of this work was to optimize a fermented soy product formulation with kefir and soy, oat and wheat fibers and to evaluate the fiber and product characteristics. A simplex-centroid mixture design was used for the optimization. Soymilk, soy, oat and wheat fiber mixtures, sucrose and anti-foaming agent were used for the formulation, followed by thermal treatment, cooling and the addition of flavoring. Fermentation was performed at 25 °C with a kefir culture until a pH of 4.5 was obtained. The products were cooled, homogenized and stored for analysis. From the mathematical models and variables response surface and desirability an optimal fermented product was formulated containing 3% (w/w) soy fiber. Compared with the other formulations, soy fermented product with 3% soy fiber had the best acidity, viscosity, syneresis, firmness and Lactococcus lactis count. PMID:23876105

  12. Modeling and simulation of centroid and inversion charge density in cylindrical surrounding gate MOSFETs including quantum effects

    An analytical model for surrounding gate metal—oxide—semiconductor field effect transistors (MOSFETs) considering quantum effects is presented. To achieve this goal, we have used a variational approach for solving the Poissonand Schrodinger equations. This model is developed to provide an analytical expression for the inversion charge distribution function for all regions of the device operation. This expression is used to calculate the other important parameters like the inversion charge centroid, threshold voltage and inversion charge density. The calculated expressions for the above parameters are simple and accurate. The validity of this model was checked for the devices with different device dimensions and bias voltages. The calculated results are compared with the simulation results and they show good agreement. (semiconductor devices)

  13. Astrometric Image Centroid Displacements due to Gravitational Microlensing by the Ellis Wormhole

    Toki, Yukiharu; Kitamura, Takao; Asada, Hideki; Abe, Fumio

    2011-01-01

    Continuing work initiated in an earlier publication (Abe, ApJ, 725 (2010) 787), we study the gravitational microlensing effects of the Ellis wormhole in the weak-field limit. First, we find a suitable coordinate transformation, such that the lens equation and analytic expressions of the lensed image positions can become much simpler than the previous ones. Second, we prove that two images always appear for the weak-field lens by the Ellis wormhole. By using these analytic results, we discuss ...

  14. Radiation Organ Doses Received in a Nationwide Cohort of U.S. Radiologic Technologists: Methods and Findings

    Steven L Simon; Preston, Dale L.; Linet, Martha S.; Miller, Jeremy S.; Sigurdson, Alice J.; Bruce H Alexander; Kwon, Deukwoo; Yoder, R. Craig; Bhatti, Parveen; Little, Mark P.; Rajaraman, Preetha; Melo, Dunstana; Drozdovitch, Vladimir; Weinstock, Robert M.; Doody, Michele M.

    2014-01-01

    In this article, we describe recent methodological enhancements and findings from the dose reconstruction component of a study of health risks among U.S. radiologic technologists. An earlier version of the dosimetry published in 2006 used physical and statistical models, literature-reported exposure measurements for the years before 1960, and archival personnel monitoring badge data from cohort members through 1984. The data and models previously described were used to estimate annual occupat...

  15. The Shortlist Method for Fast Computation of the Earth Mover's Distance and Finding Optimal Solutions to Transportation Problems

    Gottschlich, Carsten; Schuhmacher, Dominic

    2014-01-01

    Finding solutions to the classical transportation problem is of great importance, since this optimization problem arises in many engineering and computer science applications. Especially the Earth Mover's Distance is used in a plethora of applications ranging from content-based image retrieval, shape matching, fingerprint recognition, object tracking and phishing web page detection to computing color differences in linguistics and biology. Our starting point is the well-known revised simplex ...

  16. Experiences of racism and discrimination among migrant care workers in England: findings from a mixed-methods research project

    Stevens, Martin; Hussein, Shereen; Manthorpe, Jill

    2011-01-01

    Abstract Abstract This article reports part of the findings of research undertaken in 2007-09 that aimed to investigate the contribution made by migrant workers to the care workforce in England. The study involved analysis of national statistics on social care and social workers and semi-structured interviews with a wide range of stakeholders, including 96 migrant care workers. The interviews elicited some accounts relating experiences of racism and discrimination from some peo...

  17. Experimental Validation of the Dynamic Inertia Measurement Method to Find the Mass Properties of an Iron Bird Test Article

    Chin, Alexander; Herrera, Claudia; Spivey, Natalie; Fladung, William; Cloutier, David

    2015-01-01

    This presentation describes the DIM method and how it measures the inertia properties of an object by analyzing the frequency response functions measured during a ground vibration test (GVT). The DIM method has been in development at the University of Cincinnati and has shown success on a variety of small scale test articles. The NASA AFRC version was modified for larger applications.

  18. Finding Solutions to the Picard Boundary Value Problem via Homotopy Method%用同伦方法求Picard边值问题的解

    李兰; 徐旭

    2008-01-01

    This paper deals with the problem of finding solutions to the Picard boundary problem. In our approach, by means of the homotopy method, the equation considered is linked to a simpler equation by introducing a parameter. We first find the solutions of the simpler equation, and give a priori estimates of" the equa tion we considered, and then one can obtain the solutions of Picard boundary problem by following the path of solutions of Cauchy problem.

  19. 汶川地震前后地磁Z分量的谱质心变化%The Spectrum Centroid Variation in Geomagnetic Z Component Data before and after the Wenchuan Earthquake

    许康生; 辛长江; 李英

    2014-01-01

    提取了汶川地震前后成都台、木里台和西昌台地磁观测的 Z 分量数据,分3个时段对采样率为每秒一个点的观测数据每小时计算一个最大谱质心、平均谱质心和谱质心标准差。不同台站和不同时段谱质心的结果比较表明,三个参数在汶川地震前这一时段,成都台地磁 Z 分量显示较大的变化幅度,并存在震前逐渐升高的变化趋势,而其它台站和其它时段没有显示如此明显的特征。对比分析表明,成都台地磁 Z 分量显示出的谱质心变化是一个与汶川地震有关联的特征信息,且这一特征的出现与台站和震中的距离有关。对这一问题的深入研究,对于研究震磁关系、大地震的孕震机理,大地震的预测及大震发生位置的推测具有积极意义。%Research on the seismo-geomagnetic effect goes back more than 100 years,but the use of modern methods and experimentation began in the middle of the last century.Some geomagnet-ically abnormal changes have been reported before large earthquakes,e.g.,the Alaska earthquake (March 27,1964),the Loma Prieta earthquake (M7.1,Oct,17,1989),and the Iwateken Nairku Hokubu earthquake(M6.1,Sep.3,1998).The Wenchuan earthquake was the largest one after the Tangshan earthquake in China.It is important to explore the mechanism of great earthquakes when studying the Wenchuan earthquake.In this paper,we study vertical component (compo-nent) geomagnetic data observed by three stations (Chengdu station (CDP ),MuLi station (MUL),and XiChang station(XIC))in Sichuan Province,with a data sampling rate of one point per second.The maximum spectral centroid,the average spectral centroid,and the spectral cen-troid standard deviation were calculated hourly over three time segments (May 1,2008 to May 12, 2008,May 1,2009 to May 12,2009,and May 1,2010 to May 12,2010).The purpose of this time segment division is,first,to reduce seasonal disturbance,and,second,to avoid

  20. The Continuing Search to Find a More Effective and Less Intimidating Way to Teach Research Methods in Higher Education

    Bell, Robin

    2016-01-01

    Existing literature examining the teaching of research methods highlights difficulties students face when developing research competencies. Studies of student-centred teaching approaches have found increased student performance and improved confidence in undertaking research projects. To develop a student-centred approach, it could be beneficial…

  1. Tomography methods for diagnostic examination of cerebrovascular disease: a comparative evaluation of SPECT, PET and MR/CT findings

    Single Photon Emissions Computerized Tomography (SPECT), Positron Emissions Tomography (PET), Magnetic Resonance Tomography (MR), and Transmission Computerized Tomography (CT) complement each other and lead to a consideration of the cerebrovascular disease under patho-physiological aspects. Indications for the combined application of functionally oriented (SPECT/PET) and morphologically oriented (CT/MR) examination methods with cerebrovascular disease are presented. (orig./MG)

  2. OMERACT 10 sharp symposium: important findings in examination of imaging methods for measurement of joint damage in rheumatoid arthritis

    Strand, Vibeke; Kingsbury, Sarah R; Woodworth, Thasia; Landewé, Robert; Østergaard, Mikkel; Peterfy, Charles; van der Heijde, Désirée; D'Agostino, Maria-Antonietta; Maksymowych, Walter; Tak, Paul P; Wells, George; Conaghan, Philip G

    2011-01-01

    The Sharp Symposium was held at the Outcome Measures in Rheumatology Clinical Trials 2010 meeting (OMERACT 10) in honor of the late John Sharp, consummate rheumatologist and researcher. The symposium focused on the status of current scoring methods in radiography, magnetic resonance imaging (MRI...

  3. Six Forms of Variety in Students' Moral Reasoning: An Age-Old Distinction Enabling New Methods and Findings

    Backman, Ylva; Gardelli, Viktor

    2015-01-01

    In this study, the age-old distinction between decision method and criterion of rightness, commonly employed in normative ethics, was used to attain a detailed understanding of inter- and intrapersonal variety in students' moral reasoning. A total of 24 Swedish students, 12-15 years of age, were interviewed. Inter- and intrapersonal varieties in…

  4. Assessing the impacts of regional characteristics on the location of manufacturing facilities: A review of recent methods and findings

    Calzonetti, F.J. [West Virginia Univ., Morgantown, WV (United States). Dept. of Geology and Geography; Hemphill, R.C. [Argonne National Lab., IL (United States). Environmental Assessment and Information Sciences Div.

    1992-01-01

    This report gives federal agencies background information to help them assess the impacts that siting a nuclear-waste storage facility could have on industries making location decisions in various regions of influence. It reviews two major research methods used to analyze reasons for location choices: economic-based or econometric methods and survey-based factor-ranking methods. It summarizes the results of studies that have used these methods, identifying and ranking factors shown to be important to industries making location decisions throughout the nation and in western states. Neither economic-based nor survey-based studies have shown the public`s perceptions of a region to be an important determinant in the selection of new manufacturing sites, although consideration of the level of amenities is gaining importance in the West. In general, available studies are inconclusive with respect to the extent to which perceptions about hazards play a role in the location of manufacturing facilities in any region of the nation.

  5. Assessing the impacts of regional characteristics on the location of manufacturing facilities: A review of recent methods and findings

    Calzonetti, F.J. (West Virginia Univ., Morgantown, WV (United States). Dept. of Geology and Geography); Hemphill, R.C. (Argonne National Lab., IL (United States). Environmental Assessment and Information Sciences Div.)

    1992-01-01

    This report gives federal agencies background information to help them assess the impacts that siting a nuclear-waste storage facility could have on industries making location decisions in various regions of influence. It reviews two major research methods used to analyze reasons for location choices: economic-based or econometric methods and survey-based factor-ranking methods. It summarizes the results of studies that have used these methods, identifying and ranking factors shown to be important to industries making location decisions throughout the nation and in western states. Neither economic-based nor survey-based studies have shown the public's perceptions of a region to be an important determinant in the selection of new manufacturing sites, although consideration of the level of amenities is gaining importance in the West. In general, available studies are inconclusive with respect to the extent to which perceptions about hazards play a role in the location of manufacturing facilities in any region of the nation.

  6. Finding a Way into a Family of Tone Languages: The Story and Methods of the Chatino Language Documentation Project

    Cruz, Emily; Woodbury, Anthony C.

    2014-01-01

    We give a narrative description of our ten-year path into the elaborate tonal systems of the Chatino languages (Otomanguean; Oaxaca, Mexico), and of some of the methods we have used and recommend, illustrated with specific examples. The work, ongoing at the time of writing, began when one of us (Cruz), a native speaker of San Juan Quiahije…

  7. A Method for Finding Solutions of the Hermitian Theory of Relativity which Depend on Three Co-ordinates

    Antoci, S.

    2001-01-01

    A method is presented, which can generate solutions of the Hermitian theory of relativity from known solutions of the general theory of relativity, when the latter depend on three co-ordinates and are invariant under reversal of the fourth one.

  8. Intuition based decision making methodology for ranking fuzzy numbers using centroid point and spread

    Abu Bakar, Ahmad Syafadhli Bin

    2015-01-01

    The concept of ranking fuzzy numbers has received significant attention from the research community due to its successful applications for decision making. It complements the decision maker exercise their subjective judgments under situations that are vague, imprecise, ambiguous and uncertain in nature. The literature on ranking fuzzy numbers show that numerous ranking methods for fuzzy numbers are established where all of them aim to correctly rank all sets of fuzzy numbers that mimic real d...

  9. Robust seed selection algorithm for k-means type algorithms - Optimal centroids using high density object

    K. Karteeka Pavan; Allam Appa Rao; A.V. Dattatreya Rao; Sridhar, G. R.

    2011-01-01

    Selection of initial seeds greatly affects the quality of the clusters and in k-means typealgorithms. Most of the seed selection methods result different results in different independent runs. Wepropose a single, optimal, outlier insensitive seed selection algorithm for k-means type algorithms asextension to k-means++. The experimental results on synthetic, real and on microarray data setsdemonstrated that effectiveness of the new algorithm in producing the clustering results

  10. Essential features influencing collaboration in team-based non-specific back pain rehabilitation: Findings from a mixed methods study

    Hellman, Therese; Jensen, Irene; Bergström, Gunnar; Brämberg, Elisabeth Björk

    2016-01-01

    ABSTRACT The aim of the study presented in this article was to explore how professionals, without guidelines for implementing interprofessional teamwork, experience the collaboration within team-based rehabilitation for people with back pain and how this collaboration influences their clinical practice. This study employed a mixed methods design. A questionnaire was answered by 383 participants and 17 participants were interviewed. The interviews were analysed using content analysis. The quan...

  11. Meat intake, cooking methods, dietary carcinogens, and colorectal cancer risk: findings from the Colorectal Cancer Family Registry

    Joshi, Amit D.; Kim, Andre; Lewinger, Juan Pablo; Ulrich, Cornelia M.; Potter, John D; Cotterchio, Michelle; Le Marchand, Loic; Stern, Mariana C.

    2015-01-01

    Diets high in red meat and processed meats are established colorectal cancer (CRC) risk factors. However, it is still not well understood what explains this association. We conducted comprehensive analyses of CRC risk and red meat and poultry intakes, taking into account cooking methods, level of doneness, estimated intakes of heterocyclic amines (HCAs) that accumulate during meat cooking, tumor location, and tumor mismatch repair proficiency (MMR) status. We analyzed food frequency and porti...

  12. Teacher Characteristics and Student Achievements in TIMSS. Findings Gained from Applying the "First-Difference" Method to TIMSS-2007 Data

    Tatiana Khavenson; Yulia Tyumeneva

    2012-01-01

    The advantage of Trends in International Mathematics and Science Study is that not only does it perform a direct cognitive assessment of students concerning these students' teachers, but also their education, work experience and the instructional strategies used in their classes. In order to estimate teachers’ characteristics effects on a student’s achievements and overcome the limits of the TIMSS' correlational design, we have employed the first-difference method. Teachers’ characteristics e...

  13. Aims, methods and preliminary findings of the Physical Activity, Nutrition and Allergies in Children Examined in Athens (PANACEA) epidemiological study

    Papadimitriou Anastasios; Anthracopoulos Michael B; Panagiotakos Demosthenes B; Priftis Kostas N; Nicolaidou Polyxeni

    2007-01-01

    Abstract Background To determine the prevalence of asthma symptoms in a sample of Greek children aged 10–12 years, and to evaluate these rates in relation to anthropometric, lifestyle characteristics and dietary habits. Methods During 2006, 700 schoolchildren (323 male and 377 female), aged 10–12 years (4th to 6th school grade), were selected from 18 schools located in the greater Athens area. The schools were randomly selected from a list provided by the regional educational offices. To achi...

  14. Research on subpixel location error of weighted centroiding algorithm%加权质心法亚像元定位误差研究

    李朋; 高立民; 吴易明; 刘爱敏

    2011-01-01

    Weighted centroiding algorithm is often used in the subpixel location measurement process of CCD star tracker and photoelectric autocollimator, it directly affects the locating accuracy of the system, therefore, it is of great significance to research on the error analysis of weighted centroiding algorithm. Basing on the principle of centroiding algorithm,causes of error were analyzed in detail in this article, and also error calculation formulas of centroiding algorithm and weighted centroiding algorithm were deduced later. Then with the facula as a case, the systematic error and random error were quantitatively analyzed and compared. Analysis shows that.facular size has an important effect on the system measurement accuracy, suitable dispersion of the facula can improve the measurement accuracy.%加权质心法常用于CCD星敏感器或自准直仪的亚像元定位细分过程,它直接影响着系统的定位精度,因此对加权质心法的误差分析有着极重要的意义.从质心法原理出发,详细分析了误差产生的原因,并推导出了质心法和加权质心法的误差计算公式.然后以点斑为例,对其系统误差和随机误差进行了定量分析和比较.分析证明,光斑大小对于系统的测量精度有着重要的影响,合理对光斑进行弥散可以达到提高测量精度的目的.

  15. Characterization of a millefiori glass find from Aquincum by SEM-EDX and micro-PIXE methods

    Uzonyi, I., E-mail: uzonyi@atomki.hu [Institute of Nuclear Research of the Hungarian Academy of Sciences, H-4026 Debrecen, Bem ter 18/C (Hungary); Csontos, K.; Verebes, A. [Budapest History Museum, Aquincum Museum H-8211 Budapest, Zahony u. 4. (Hungary); Cserhati, C. [Department of Solid State Physics, University of Debrecen H-4032 Debrecen, Bem ter 18/B (Hungary); Csedreki, L.; Kis-Varga, M.; Kiss, A.Z. [Institute of Nuclear Research of the Hungarian Academy of Sciences, H-4026 Debrecen, Bem ter 18/C (Hungary)

    2011-10-15

    Research has been focused on the analysis of archaeological glasses from the Roman age and medieval times. Study of ancient millefiori type glasses from the collection of Hungarian Museums has been started. A test measurement, carried out on a glass fragment supposedly part of a dish, was performed by SEM-EDX and micro-PIXE methods. Complementary analytical data were obtained for texture and composition. Results suggest that Roman and Mesopotamian techniques were used together. Our data contribute to data bases of millefiori glasses.

  16. Ground experiments for finding principles and working out methods for preventing adverse effects of weightlessness on the human organism

    Kakurin, L. I.; Gregoryev, A. I.; Mikhailov, V. M.; Tishler, V. A.

    1980-01-01

    A comparative assessment of the effectiveness of different prophylactic procedures to prevent the adverse effects of weightlessness is presented. It is concluded that: physical training is most effective but no single method by itself produces the full effect, and an adjustment of regimes to one another enhances the effect. The approved complex of prophylactic procedures affected basic changes occurring in hypokinesia: deficit of muscular activity, no or reduced BP hydrostatic component, reduced volume of blood circulation, reduced hydration level, and the application of various prophylactic complexes during 49 day antiorthostatic hypodynamia eliminated or reduced the adverse effects of weightlessness in simulation.

  17. A Finding Method of Business Risk Factors Using Characteristics of Probability Distributions of Effect Ratios on Qualitative and Quantitative Hybrid Simulation

    Samejima, Masaki; Negoro, Keisuke; Mitsukuni, Koshichiro; Akiyoshi, Masanori

    We propose a finding method of business risk factors on qualitative and quantitative hybrid simulation in time series. Effect ratios of qualitative arcs in the hybrid simulation vary output values of the simulation, so we define effect ratios causing risk as business risk factors. Finding business risk factors in entire ranges of effect ratios is time-consuming. It is considered that probability distributions of effect ratios in present time step and ones in previous time step are similar, the probability distributions in present time step can be estimated. Our method finds business risk factors in only estimated ranges effectively. Experimental results show that a precision rate and a recall rate are 86%, and search time is decreased 20% at least.

  18. [Low dose ionising radiation and cancer: findings and methods. Report of a meeting and consequences for Switzerland].

    Schüler, G; Gutzwiller, F

    1991-01-01

    Today's society is concerned about the dangers of ionising radiation, especially in the aftermath of Chernobyl. On the other hand, there exists a widespread lack of understanding radiation biology and radioepidemiology--the very sciences which provide the data from which today's risk estimates have been derived. The papers in this issue of the Journal were presented at a workshop on "Low level radiation and cancer: data and methods" held on 10th-11th December in Feuisberg, near Zurich. The meeting was organised by the Institute of Social and Preventive Medicine of the University of Zurich under the auspices of the Swiss Federal Office of Public Health. Its aims were threefold. First, to give an introduction to some basic facts and methodological issues in radiation physics, biology and epidemiology. Secondly, to give an overview of the availability of data for radioepidemiological research in Switzerland and, thirdly, to evaluate possible research strategies in this country. A list of some notions and units commonly used in the radiation sciences serves an an introduction to the field (G. Schüler et al.). In using units and notions it is important to distinguish the description of biological experiments and epidemiological observations from definitions and risk projections proposed by international reports and consensus bodies for radioprotection purposes. The next papers deal more specifically with selected aspects of the basic sciences. Dosimetry means quantifying the physical effects of ionizing radiation in human tissue; this is not a straight-forward procedure (I. Cordt). The foundations of general radiation biology are succinctly summarised by C. Michel. An account of our present knowledge and theories of radiation carcinogenesis is provided by W. Burkart. W Lutz compares dose-response models of chemical carcinogenesis with those used in radiation carcinogenesis. During the last decade the epidemiological foundations of radioprotection have changed

  19. Suppressing beam-centroid motion in a long-pulse linear induction accelerator

    Ekdahl, Carl; Abeyta, E. O.; Archuleta, R.; Bender, H.; Broste, W.; Carlson, C.; Cook, G.; Frayer, D.; Harrison, J.; Hughes, T.; Johnson, J.; Jacquez, E.; McCuistian, B. Trent; Montoya, N.; Nath, S.; Nielsen, K.; Rose, C.; Schulze, M.; Smith, H. V.; Thoma, C.; Tom, C. Y.

    2011-12-01

    The second axis of the dual-axis radiography of hydrodynamic testing (DARHT) facility produces up to four radiographs within an interval of 1.6μs. It does this by slicing four micropulses out of a 2-μs long electron beam pulse and focusing them onto a bremsstrahlung converter target. The 1.8-kA beam pulse is created by a dispenser cathode diode and accelerated to more than 16 MeV by the unique DARHT Axis-II linear induction accelerator (LIA). Beam motion in the accelerator would be a problem for multipulse flash radiography. High-frequency motion, such as from beam-breakup (BBU) instability, would blur the individual spots. Low-frequency motion, such as produced by pulsed-power variation, would produce spot-to-spot differences. In this article, we describe these sources of beam motion, and the measures we have taken to minimize it. Using the methods discussed, we have reduced beam motion at the accelerator exit to less than 2% of the beam envelope radius for the high-frequency BBU, and less than 1/3 of the envelope radius for the low-frequency sweep.

  20. Optical telecommunications system and signal analysis using data-entropy and multiple-centroid data-scatter

    Egan, J.; McMillan, N. D.; Denieffe, D.; Riedel, S.; Doyle, G.; Farrell, G.

    2005-09-01

    The data-entropy quality-budget developed by the authors is used as an alternative to the conventional power budget. The traditional power budget approach is not capable of providing a full analysis of a system with different noise types and specifically providing a measure of signal quality. The quality-budget addressed this issue by applying its dimensionless 'bit measure' to integrate the analysis of all types of losses. A data-entropy visualisation is produced for each set of points in a reference and test signal. This data-entropy signal is a measure of signal disorder and reflects the power loss and types of signal degradation experienced by the test signal. To analyse the differences between two signals an algorithm known as phase-coherent data-scatter (PCDS) is used to assess levels of attenuation, dispersion, jitter, etc. Practical analysis of telecommunications signals using the new multiple-centroid (MC) PCDS is presented here for the first time. MC-PCDS is then used to analyse differences between sets of data-entropy signals and digital signals. The theory behind MC data-scatter is discussed and its advantages for the quantification of signal degradations are assessed. Finally, a brief consideration is given to the use of pattern recognition algorithms to measure optical signal degrading factors.

  1. Numerical methods for finding periodic points in discrete maps. High order islands chains and noble barriers in a toroidal magnetic configuration

    We first remind usual physical and mathematical concepts involved in the dynamics of Hamiltonian systems, and namely in chaotic systems described by discrete 2D maps (representing the intersection points of toroidal magnetic lines in a poloidal plane in situations of incomplete magnetic chaos in Tokamaks). Finding the periodic points characterizing chains of magnetic islands is an essential step not only to determine the skeleton of the phase space picture, but also to determine the flux of magnetic lines across semi-permeable barriers like Cantori. We discuss here several computational methods used to determine periodic points in N dimensions, which amounts to solve a set of N nonlinear coupled equations: Newton method, minimization techniques, Laplace or steepest descend method, conjugated direction method and Fletcher-Reeves method. We have succeeded to improve this last method in an important way, without modifying its useful double-exponential convergence. This improved method has been tested and applied to finding periodic points of high order m in the 2D 'Tokamap' mapping, for values of m along rational chains of winding number n/m converging towards a noble value where a Cantorus exists. Such precise positions of periodic points have been used in the calculation of the flux across this Cantorus. (authors)

  2. A new method for the discovery of the best threshold value for finding positive or negative association rules using Binary Particle Swarm Optimization

    Abdoljabbar Asadi

    2012-11-01

    Full Text Available In association rule mining most of former researches have worked on analytic optimizing method , but finding and specifying the advocate initiation limit influences on association rule mining's quality , which still is important hence this research wants to present a new algorithm for optimizing the analytic efficiency improvement including automatic analyze proper amount for initiation. Through former method this task had been performing based on positive rules but regarding that finding the negative ones were though for administrator, this research's privilege is that the initiation level automatically is analyzed for the first time; also it has high efficiency in large data base. Particle Swarm Optimization is observed for any particle's efficiency and as data turned in binary the advocate amount will be found. Results showed Particle Swarm Optimization could present better initiation level, and enhance the former algorithm's result a lot. Consequence will be comparing with Weka and Apriori.

  3. Finding Sliesthorp?

    Dobat, Andres S.

    2016-01-01

    In 2003, a hitherto unknown Viking age settlement was discovered at Füsing in Northern Germany close to Hedeby/Schleswig, the largest of the early Scandinavian towns. Finds and building features suggest a high status residence and a seat of some chiefly elite that flourished from around 700 to the...

  4. The New Multi-HAzard and MulTi-RIsK Assessment MethodS for Europe (MATRIX) Project - An overview of its major findings

    Fleming, Kevin; Zschau, Jochen; Gasparini, Paolo

    2014-05-01

    Recent major natural disasters, such as the 2011 Tōhoku earthquake, tsunami and subsequent Fukushima nuclear accident, have raised awareness of the frequent and potentially far-reaching interconnections between natural hazards. Such interactions occur at the hazard level, where an initial hazard may trigger other events (e.g., an earthquake triggering a tsunami) or several events may occur concurrently (or nearly so), e.g., severe weather around the same time as an earthquake. Interactions also occur at the vulnerability level, where the initial event may make the affected community more susceptible to the negative consequences of another event (e.g., an earthquake weakens buildings, which are then damaged further by windstorms). There is also a temporal element involved, where changes in exposure may alter the total risk to a given area. In short, there is the likelihood that the total risk estimated when considering multiple hazard and risks and their interactions is greater than the sum of their individual parts. It is with these issues in mind that the European Commission, under their FP7 program, supported the New Multi-HAzard and MulTi-RIsK Assessment MethodS for Europe or MATRIX project (10.2010 to 12.2013). MATRIX set out to tackle multiple natural hazards (i.e., those of concern to Europe, namely earthquakes, landslides, volcanos, tsunamis, wild fires, storms and fluvial and coastal flooding) and risks within a common theoretical framework. The MATRIX work plan proceeded from an assessment of single-type risk methodologies (including how uncertainties should be treated), cascade effects within a multi-hazard environment, time-dependent vulnerability, decision making and support for multi-hazard mitigation and adaption, and an assessment of how the multi-hazard and risk viewpoint may be integrated into current decision making and risk mitigation programs, considering the existing single-hazard and risk focus. Three test sites were considered during the

  5. A Centroid Model of Species Distribution to Analyize Multi-directional Climate Change Finger Print in Avian Distribution in North America

    Huang, Q.; Sauer, J.; Dubayah, R.

    2015-12-01

    Species distribution shift (or referred to as "fingerprint of climate change") as a primary mechanism to adapt climate change has been of great interest to ecologists and conservation practitioners. Recent meta-analyses have concluded that a wide range of animal and plant species are already shifting their distribution. However majority of the literature has focused on analyzing recent poleward and elevationally upward shift of species distribution. However if measured only in poleward shifts, the fingerprint of climate change will be underestimated significantly. In this study, we demonstrate a centroid model for range-wide analysis of distribution shifts using the North American Breeding Bird Survey. The centroid model is based on a hierarchical Bayesian framework which models population change within physiographic strata while accounting for several factors affecting species detectability. We used the centroid approach to examine large number of species permanent resident species in North America and evaluated the dreiction and magnitude of their shifting distribution. To examine the inferential ability of mean temperature and precipitation, we test a hypothesis based on climate velocity theory that species would be more likely to shift their distribution or would shift with greater magnitude in in regions with high climate change velocity. For species with significant shifts of distribution, we establish a precipitation model and a temperature model to explain their change of abundance at the strata level. Two models which are composed of mean and extreme climate indices respectively are also established to test the influences of changes in gradual and extreme climate trends.

  6. The Two-Phase Method for Finding a Great Number of Eigenpairs of the Symmetric or Weakly Non-symmetric Large Eigenvalue Problems

    Dul, Franciszek A.; Arczewski, Krzysztof

    1994-03-01

    Although it has been stated that "an attempt to solve (very large problems) by subspace iterations seems futile" (H. G. Matthies, Comput. Struct.21 (1985), p. 324), we will show that the statement is not true, especially for extremely large eigenproblems. In this paper a new two-phase subspace iteration/Rayleigh quotient/conjugate gradient method for generalized, large, symmetric eigenproblems Ax = λBx is presented. It has the ability of solving extremely large eigenproblems, N = 216,000, for example, and finding a large number of leftmost or rightmost eigenpairs, up to 1000 or more. Multiple eigenpairs, even those with multiplicity 100, can be easily found. The use of the proposed method for solving the big full eigenproblems ( N ˜ 10 3), as well as for large weakly non-symmetric eigenproblems, have been considered also. The proposed method is fully iterative; thus the factorization of matrices is avoided. The key idea consists in joining two methods: subspace and Rayleigh quotient iterations. The systems of indefinite and almost singular linear equations ( A - σ B) x = By are solved by various iterative conjugate gradient/Lanczos methods. It will be shown that the standard conjugate gradient method can be used without danger of breaking down due to its property that may be called "self-correction towards the eigenvector," discovered recently by us. The use of various preconditioners (SSOR and IC) has also been considered. The main features of the proposed method have been analyzed in detail. Comparisons with other methods, such as, accelerated subspace iteration, Lanczos, Davidson, TLIME, TRACMN, and SRQMCG, are presented. The results of numerical tests for various physical problems (acoustic, vibrations of structures, quantum chemistry) are presented as well. The final conclusion is that our new method is usually much faster than other iterative methods, especially for very large eigenproblems arising from 3D elliptic or biharmonic problems defined on

  7. Global pathways to men's caregiving: mixed methods findings from the International Men and Gender Equality Survey and the Men Who Care study.

    Kato-Wallace, Jane; Barker, Gary; Eads, Marci; Levtov, Ruti

    2014-01-01

    Promoting men's participation in unpaid care work is part of the Programme of Action for the International Conference on Population and Development. However, men's involvement in care work does not mirror the advances women have made in paid work outside the home. This mixed method study explores which men are more involved in caregiving, and what childhood and adulthood factors influence their level of involvement. Quantitative research presents findings from 1169 men across six countries with children aged 0-4, and a qualitative study presents findings from in-depth interviews with 83 men engaged in atypical caregiving practices. Survey research finds that being taught to care for children, witnessing one's father take care of one's siblings, respondents' present attitudes about gender equality and having outside help (or none, in some cases) were all also associated with men's higher level of involvement. Qualitative research reveals that men's experiences of violence, the normalisation of domestic work as children and life circumstances rather than greater-than-average beliefs in gender equality all propelled them into care work. Findings suggest that engaging more men into care work implies changes to policies and structural realities in the workplace coupled with changing gender attitudes. These insights inform policy and practice aimed at promoting greater involvement in care work by men. PMID:24938308

  8. A colorimetric method for highly sensitive and accurate detection of iodide by finding the critical color in a color change process using silver triangular nanoplates

    Graphical abstract: -- Highlights: •Demonstrated a new colorimetric strategy for iodide detection by silver nanoplates. •The colorimetric strategy is to find the critical color in a color change process. •The colorimetric strategy is more accurate and sensitive than common colorimetry. •Discovered a new morphological transformation phenomenon of silver nanoplates. -- Abstract: In this contribution, we demonstrated a novel colorimetric method for highly sensitive and accurate detection of iodide using citrate-stabilized silver triangular nanoplates (silver TNPs). Very lower concentration of iodide can induce an appreciable color change of silver TNPs solution from blue to yellow by fusing of silver TNPs to nanoparticles, as confirmed by UV–vis absorption spectroscopy and transmission electron microscopy (TEM). The principle of this colorimetric assay is not an ordinary colorimetry, but a new colorimetric strategy by finding the critical color in a color change process. With this strategy, 0.1 μM of iodide can be recognized within 30 min by naked-eyes observation, and lower concentration of iodide down to 8.8 nM can be detected using a spectrophotometer. Furthermore, this high sensitive colorimetric assay has good accuracy, stability and reproducibility comparing with other ordinary colorimetry. We believe this new colorimetric method will open up a fresh insight of simple, rapid and reliable detection of iodide and can find its future application in the biochemical analysis or clinical diagnosis

  9. A colorimetric method for highly sensitive and accurate detection of iodide by finding the critical color in a color change process using silver triangular nanoplates

    Yang, Xiu-Hua; Ling, Jian, E-mail: lingjian@ynu.edu.cn; Peng, Jun; Cao, Qiu-E., E-mail: qecao@ynu.edu.cn; Ding, Zhong-Tao; Bian, Long-Chun

    2013-10-10

    Graphical abstract: -- Highlights: •Demonstrated a new colorimetric strategy for iodide detection by silver nanoplates. •The colorimetric strategy is to find the critical color in a color change process. •The colorimetric strategy is more accurate and sensitive than common colorimetry. •Discovered a new morphological transformation phenomenon of silver nanoplates. -- Abstract: In this contribution, we demonstrated a novel colorimetric method for highly sensitive and accurate detection of iodide using citrate-stabilized silver triangular nanoplates (silver TNPs). Very lower concentration of iodide can induce an appreciable color change of silver TNPs solution from blue to yellow by fusing of silver TNPs to nanoparticles, as confirmed by UV–vis absorption spectroscopy and transmission electron microscopy (TEM). The principle of this colorimetric assay is not an ordinary colorimetry, but a new colorimetric strategy by finding the critical color in a color change process. With this strategy, 0.1 μM of iodide can be recognized within 30 min by naked-eyes observation, and lower concentration of iodide down to 8.8 nM can be detected using a spectrophotometer. Furthermore, this high sensitive colorimetric assay has good accuracy, stability and reproducibility comparing with other ordinary colorimetry. We believe this new colorimetric method will open up a fresh insight of simple, rapid and reliable detection of iodide and can find its future application in the biochemical analysis or clinical diagnosis.

  10. Method of transient identification based on a possibilistic approach, optimized by genetic algorithm

    This work develops a method for transient identification based on a possible approach, optimized by Genetic Algorithm to optimize the number of the centroids of the classes that represent the transients. The basic idea of the proposed method is to optimize the partition of the search space, generating subsets in the classes within a partition, defined as subclasses, whose centroids are able to distinguish the classes with the maximum correct classifications. The interpretation of the subclasses as fuzzy sets and the possible approach provided a heuristic to establish influence zones of the centroids, allowing to achieve the 'don't know' answer for unknown transients, that is, outside the training set. (author)

  11. Research progress on intervention method of promoting benefit finding%提升益处发现的干预方法研究进展

    邵丽华

    2015-01-01

    There were many intervention methods that mainly included cognitive behavior management,stress management,peer support,complementary and alternative medicine and positive reflection to promote benefit finding.The intervention obj ects mainly focused on patients with breast cancer or alzheimer’s disease or AIDS. It put forward that the study on benefit finding was still in the stage of exploration.%提高益处发现的干预方法主要有认知行为管理、压力管理、同伴支持、补充和替代疗法、积极反思等方法,干预对象主要集中于乳腺癌、阿尔兹海默病、艾滋病病人等。提出益处发现的研究尚处于探索阶段。

  12. Reliability of change in lumbar MRI findings over time in patients with and without disc prosthesis - comparing two different image evaluation methods

    To assess the reliability of change in lumbar magnetic resonance imaging (MRI) findings evaluated retrospectively by direct comparison of images and by non-comparison. Pre-treatment and 2-year follow-up MRI was performed in 126 patients randomized to disc prosthesis surgery or non-surgical treatment. Two experienced radiologists independently evaluated progress and regress for Modic changes, disc findings, and facet arthropathy (FA) at L3/L4, L4/L5, and L5/S1, both by non-comparison and by comparison of initial and follow-up images. FA was evaluated at all levels, and other findings at non-operated levels. We calculated prevalence- and bias-adjusted kappa (PABAK) values for interobserver agreement. The impact of an adjacent prosthesis (which causes artefacts) and image evaluation method on PABAK was assessed using generalized estimating equations. Image comparison indicated good interobserver agreement on progress and regress (PABAK 0.63-1.00) for Modic changes, posterior high-intensity zone, disc height, and disc contour at L3-S1 and for nucleus pulposus signal and FA at L3/L4; and moderate interobserver agreement (PABAK 0.46-0.59) on decreasing nucleus signal and increasing FA at L4-S1. Image comparison indicated lower (but fair) interobserver agreement (PABAK 0.29) only for increasing FA at L5/S1 in patients with prosthesis in L4/L5 and/or L5/S1. An adjacent prosthesis had no overall impact on PABAK values (p ≥ 0.22). Comparison yielded higher PABAK values than non-comparison (p < 0.001). Regarding changes in lumbar MRI findings over time, comparison of images can provide moderate or good interobserver agreement, and better agreement than non-comparison. An adjacent prosthesis may not reduce agreement on change for most findings. (orig.)

  13. Reliability of change in lumbar MRI findings over time in patients with and without disc prosthesis - comparing two different image evaluation methods

    Berg, Linda; Espeland, Ansgar [Haukeland University Hospital, Department of Radiology, Bergen (Norway); University of Bergen, Section for Radiology, Department of Surgical Sciences, Bergen (Norway); Gjertsen, Oeivind [Oslo University Hospital, Department of Neuroradiology, Oslo (Norway); Hellum, Christian [Oslo University Hospital, Department of Orthopaedics, Oslo (Norway); University of Oslo, Department of Orthopaedics, Oslo (Norway); Neckelmann, Gesche [Haukeland University Hospital, Department of Radiology, Bergen (Norway); Johnsen, Lars G. [University Hospital of Trondheim, National Centre for Diseases of the Spine, Trondheim (Norway); University Hospital of Trondheim, Orthopaedic Department, Trondheim (Norway); Eide, Geir E. [Haukeland University Hospital, Centre for Clinical Research, Bergen (Norway); University of Bergen, Department of Public Health and Primary Health Care, Bergen (Norway)

    2012-12-15

    To assess the reliability of change in lumbar magnetic resonance imaging (MRI) findings evaluated retrospectively by direct comparison of images and by non-comparison. Pre-treatment and 2-year follow-up MRI was performed in 126 patients randomized to disc prosthesis surgery or non-surgical treatment. Two experienced radiologists independently evaluated progress and regress for Modic changes, disc findings, and facet arthropathy (FA) at L3/L4, L4/L5, and L5/S1, both by non-comparison and by comparison of initial and follow-up images. FA was evaluated at all levels, and other findings at non-operated levels. We calculated prevalence- and bias-adjusted kappa (PABAK) values for interobserver agreement. The impact of an adjacent prosthesis (which causes artefacts) and image evaluation method on PABAK was assessed using generalized estimating equations. Image comparison indicated good interobserver agreement on progress and regress (PABAK 0.63-1.00) for Modic changes, posterior high-intensity zone, disc height, and disc contour at L3-S1 and for nucleus pulposus signal and FA at L3/L4; and moderate interobserver agreement (PABAK 0.46-0.59) on decreasing nucleus signal and increasing FA at L4-S1. Image comparison indicated lower (but fair) interobserver agreement (PABAK 0.29) only for increasing FA at L5/S1 in patients with prosthesis in L4/L5 and/or L5/S1. An adjacent prosthesis had no overall impact on PABAK values (p {>=} 0.22). Comparison yielded higher PABAK values than non-comparison (p < 0.001). Regarding changes in lumbar MRI findings over time, comparison of images can provide moderate or good interobserver agreement, and better agreement than non-comparison. An adjacent prosthesis may not reduce agreement on change for most findings. (orig.)

  14. Temnothorax crasecundus sp. n. – a cryptic Eurocaucasian ant species (Hymenoptera, Formicidae discovered by Nest Centroid Clustering

    Bernhard Seifert

    2015-01-01

    Full Text Available The paper integrates two independent studies of numeric morphology-based alpha-taxonomy of the cryptic ant species Temnothorax crassispinus (Karavajev, 1926 and T. crasecundus sp. n. conducted by different investigators, using different equipment, considering different character combinations and evaluating different samples. Samples investigated included 603 individual workers from 203 nests – thereof 104 nest samples measured by Seifert and 99 by Csösz. The material originated from Europe, Asia Minor and Caucasia. There was a very strong interspecific overlap in any of the 29 shape characters recorded and subjective expert determination failed in many cases. Primary classification hypotheses were formed by the exploratory data analysis Nest Centroid (NC clustering and corrected to final species hypotheses by an iterative linear discriminant analysis algorithm. The evaluation of Seifert’s and Csösz’s data sets arrived at fully congruent conclusions. NC-Ward and NC-K-means clustering disagreed from the final species hypothesis in only 1.9 and 1.9% of the samples in Seifert’s data set and by 1.1 and 2.1% in Csösz’s data set which is a strong argument for heterospecificity. The type series of T. crassispinus and T. crasecundus sp. n. were allocated to different clusters with p = 0.9851 and p = 0.9912 respectively. The type series of the junior synonym T. slavonicus (Seifert, 1995 was allocated to the T. crassispinus cluster with p = 0.9927. T. crasecundus sp. n. and T. crassispinus are parapatric species with a long contact zone stretching from the Peloponnisos peninsula across Bulgaria northeast to the southern Ukraine. There is no indication for occurrence of interspecifically mixed nests or intraspecific polymorphism. However, a significant reduction of interspecific morphological distance at sites with syntopic occurrence of both species indicates local hybridization. The results are discussed within the context of the Pragmatic

  15. PERFORMANCE OF SELECTED AGGLOMERATIVE HIERARCHICAL CLUSTERING METHODS

    Nusa Erman

    2015-01-01

    Full Text Available A broad variety of different methods of agglomerative hierarchical clustering brings along problems how to choose the most appropriate method for the given data. It is well known that some methods outperform others if the analysed data have a specific structure. In the presented study we have observed the behaviour of the centroid, the median (Gower median method, and the average method (unweighted pair-group method with arithmetic mean – UPGMA; average linkage between groups. We have compared them with mostly used methods of hierarchical clustering: the minimum (single linkage clustering, the maximum (complete linkage clustering, the Ward, and the McQuitty (groups method average, weighted pair-group method using arithmetic averages - WPGMA methods. We have applied the comparison of these methods on spherical, ellipsoid, umbrella-like, “core-and-sphere”, ring-like and intertwined three-dimensional data structures. To generate the data and execute the analysis, we have used R statistical software. Results show that all seven methods are successful in finding compact, ball-shaped or ellipsoid structures when they are enough separated. Conversely, all methods except the minimum perform poor on non-homogenous, irregular and elongated ones. Especially challenging is a circular double helix structure; it is being correctly revealed only by the minimum method. We can also confirm formerly published results of other simulation studies, which usually favour average method (besides Ward method in cases when data is assumed to be fairly compact and well separated.

  16. The two-phase method for finding a great number of eigenpairs of the symmetric or weakly non-symmetric large eigenvalue problems

    Dul, F.A.; Arczewski, K. (Warsaw Univ. of Technology, Warsaw (Poland))

    1994-03-01

    Although it has been stated that [open quotes]an attempt to solve (very large problems) by subspace iterations seems futile[close quotes], we will show that the statement is not true, especially for extremely large eigenproblems. In this paper a new two-phase subspace iteration/Rayleigh quotient/conjugate gradient method for generalized, large, symmetric eigenproblems Ax = [lambda]Bx is presented. It has the ability of solving extremely large eigenproblems, N = 216,000, for example, and finding a large number of leftmost or rightmost eigenpairs, up to 1000 or more. Multiple eigenpairs, even those with multiplicity 100, can be easily found. The use of the proposed method for solving the big full eigenproblems (N [approximately] 10[sup 3]), as well as for large weakly non-symmetric eigenproblems, have been considered also. The proposed method is fully iterative; thus the factorization of matrices ins avoided. The key idea consists in joining two methods: subspace and Rayleigh quotient iterations. The systems of indefinite and almost singular linear equations (a - [sigma]B)x = By are solved by various iterative conjugate gradient method can be used without danger of breaking down due to its property that may be called [open quotes]self-correction towards the eigenvector,[close quotes] discovered recently by us. The use of various preconditioners (SSOR and IC) has also been considered. The main features of the proposed method have been analyzed in detail. Comparisons with other methods, such as, accelerated subspace iteration, Lanczos, Davidson, TLIME, TRACMN, and SRQMCG, are presented. The results of numerical tests for various physical problems (acoustic, vibrations of structures, quantum chemistry) are presented as well. 40 refs., 12 figs., 2 tabs.

  17. 面向几何坐标的张拉整体结构找形算法%Geometry-oriented form-finding method for tensegrity

    陆金钰; 李娜; 范圣刚

    2012-01-01

    A new form-finding method for computing the given nodal coordinates tensegrity was proposed. The equilibrium equation was formulated in two different ways. Based on the orthogonal vectors that were generated by the singular value decomposition of equilibrium matrix and eigenvalue decomposition of force density matrix, the self stress modes and nodal coordinates were obtained, respectively. The given nodal coordinates were introduced as constraint conditions. Self stress modes and nodal coordinates were calculated iteratively until the results converge, and the corresponding procedure was established. The topology and a set of nodal coordinates were specified in this method. The proposed approach can be applied to the form-finding of tensegrity with required shape, and the form-finding of novel nonregular tensegrity system.%提出一种可满足给定几何坐标的张拉整体结构找形方法.从结构平衡方程的2种不同形式出发,借助平衡矩阵奇异值分解与力密度矩阵特征值分解后得到的正交向量,分别构造自应力及几何坐标,并引入节点坐标作为约束条件,给出基于构件自应力与节点坐标非线性迭代的求解技术及其算法流程.结果表明,只需给出结构拓扑连接关系及若干已知节点坐标,找形算法便可用于寻找满足给定几何外形的张拉整体以及新的非规则张拉整体形式.

  18. Oscar — Using Byte Pairs to Find File Type and Camera Make of Data Fragments

    Karresand, Martin; Shahmehri, Nahid

    Mapping out the contents of fragmented storage media is hard if the file system has been corrupted, especially as the current forensic tools rely on meta information to do their job. If it was possible to find all fragments belonging to a certain file type, it would also be possible to recover a lost file. Such a tool could for example be used in the hunt for child pornography. The Oscar method identifies the file type of data fragments based solely on statistics calculated from their structure. The method does not need any meta data to work. We have previously used the byte frequency distribution and the rate of change between consecutive bytes as basis for the statistics, as well as calculating the 2-gram frequency distribution to create a model of different file types. This paper present a variant of the 2-gram method, in that it uses a dynamic smoothing factor. In this way we take the amount of data used to create the centroid into consideration. A previous experiment on file type identification is extended with .mp3 files reaching a detection rate of 76% with a false positives rate of 0.4%. We also use the method to identify the camera make used to capture a .jpg picture from a fragment of the picture. The result shows that we can clearly separate a picture fragment coming from a Fuji or Olympus cameras from a fragment of a picture of the other camera makes used in our test.

  19. CT findings of minimally invasive adenocarcinoma (MIA) of the lung and comparison of solid portion measurement methods at CT in 52 patients

    Lee, Sang Min; Lee, Kyung Hee; Park, Chang Min [Seoul National University Medical Research Center, Department of Radiology, Seoul National University College of Medicine, and Institute of Radiation Medicine, Jongno-gu, Seoul (Korea, Republic of); Goo, Jin Mo [Seoul National University Medical Research Center, Department of Radiology, Seoul National University College of Medicine, and Institute of Radiation Medicine, Jongno-gu, Seoul (Korea, Republic of); Seoul National University College of Medicine, Cancer Research Institute, Seoul (Korea, Republic of); Chung, Doo Hyun; Koh, Jaemoon [Seoul National University College of Medicine, Department of Pathology, Seoul (Korea, Republic of)

    2015-08-15

    We aimed to retrospectively investigate CT findings of minimally invasive adenocarcinoma (MIA) and to determine the appropriate method for measurement of solid portions in MIAs at CT. From May 2012 to April 2014, 55 pulmonary nodules in 52 patients were pathologically confirmed as MIAs and were included in this study. CT findings of MIAs and measurements of solid portions at CT were evaluated by two independent radiologists. Mean size of MIAs was 10.5 mm ± 4.8 (range, 4-28 mm). Fifty-two MIAs manifested as 28 pure ground glass nodules (GGNs) (53.8 % %), 22 part-solid GGNs (42.3 % %), and 2 two solid nodules (3.8 % %) at CT. Lobulated border, bubble lucency, and pleural retraction were frequently found in both observers (26.9-42.3 % %). Differences according to window settings between solid portion size and invasive component size were not significantly different in both observers (p > 0.05). As for interobserver agreement, 95 % CIs for solid portion size in the mediastinal window setting (-2.2 to 3.4; mean, 0.6) were slightly narrower than those in the lung window setting (-2.6 to 3.1; mean, 0.3). Nearly all MIAs appear as pure and part-solid GGNs. Mediastinal and lung window settings can be applied for measurement of solid portions at CT without a significant difference. (orig.)

  20. A comprehensive method to find RPO trajectory and incentive scheme for promotion of renewable energy in India with study of impact of RPO on tariff

    Renewable Purchase Obligation (RPO) regime in India started in 2011 with the announcement of benchmark RPO (BRPO) of states for the Financial Year (FY) 2011 by respective State Electricity Regulatory Commissions (SERC), to promote Renewable Energy (RE). The report submitted to Forum of Regulators (FoR) in this regard has recommended uniform rate of increase of BRPO of states and studied the impact of RPO on tariff for FY 2011–2015. However, more rigorous analysis is needed for fixing BRPO in a scientific manner and for fair allocation of incentives to promote RE. This paper attempts to evaluate all states on a common platform to find BRPO, giving due weightage to the state-wise energy demand and RE generation, ensuring minimum change in BRPO of consecutive years and hence less impact of RPO on tariff. To encourage the states to align their actual RPO with BRPO, a financial incentive scheme is proposed giving due weightage to RE consumption, RE capacity addition and RPO compliance of the states. The methods are illustrated for the Indian states using real system data. A study of RPO's impact on electricity tariff of Indian states is also conducted and reported for FY 2011–2015, considering Renewable Energy Certificate (REC). - Author-Highlights: • Proposes a comprehensive method to find the BRPO of Indian states for promoting RE. • Minimum change in BRPO of consecutive years hence less impact of RPO on tariff. • Incentive scheme to encourage the states to align their actual RPO with BRPO. • Study of impact of RPO on tariff of Indian states is conducted

  1. Main findings

    Licensing regimes vary from country to country. When the license regime involves several regulators and several licenses, this may lead to complex situations. Identifying a leading organisation in charge of overall coordination including preparation of the licensing decision is a useful practice. Also, if a stepwise licensing process is implemented, it is important to fix in legislation decisions and/or time points and to identify the relevant actors. There is considerable experience in civil and mining engineering that can be applied when constructing a deep geological disposal facility. Specific challenges are, however, the minimization of disturbances to the host rock and the understanding of its long-term behavior. Construction activities may affect the geo-hydraulic and geochemical properties of the various system components which are important safety features of the repository system. Clearly defined technical specifications and an effective quality management plan are important in ensuring successful repository implementation which is consistent with safety requirements. Monitoring plan should also be defined in advance. The regulatory organization should prepare itself to the licensing review before construction by allocating sufficient resources. It should increase its competence, e.g., by interacting early with the implementer and through its own R and D. This will allow the regulator to define appropriate technical conditions associated to the construction license and to elaborate a relevant inspection plan of the construction work. After construction, obtaining the operational license is the most important and crucial step. Main challenges include (a) establishing sufficient confidence so that the methods for closing the individual disposal units comply with the safety objectives and (b) addressing the issue of ageing of materials during a 50-100 years operational period. This latter challenge is amplified when reversibility/retrievability is required

  2. Experimental Test of Data Analysis Methods from Staggered Pair X-ray Beam Position Monitors at Bending Magnet Beamlines

    Different methods have been proposed to calculate the vertical position of the photon beam centroid from the four blade currents of staggered pair X-ray beam position monitors (XBPMs) at bending magnet beamlines since they emerged about 15 years ago. The original difference-over-sum method introduced by Peatman and Holldack is still widely used, even though it has been proven to be rather inaccurate at large beam displacements. By systematically generating bumps in the electron orbit of the ANKA storage ring and comparing synchronized data from electron BPMs and XBPM blade currents, we have been able to show that the log-ratio method by S. F. Lin, B.G. Sun et al. is superior (meaning the characteristic being closer to linear) to the ratio method, which in turn is superior to the difference over sum method. These findings are supported by simulations of the XBPM response to changes of the beam centroid. The heuristic basis for each of the methods is investigated. The implications on using XBPM readings for orbit correction are discussed

  3. New treatment method for developmental dysplasia of the hips after walking age. Arthroscopic reduction with limboplasty based on the findings of preoperative imaging

    What makes treatment choice for developmental dysplasia of the hips diagnosed after walking age difficult is the poor understanding of prereduction conditions that obstruct the reduction in spatial terms. To evaluate these problems, we employed subtraction three-dimensional imaging to search for the factors involved in intraarticular obstruction. On the basis of the findings of preoperative subtraction three-dimensional imaging from computed tomography, we developed a new method, a minimum invasive arthroscopic reduction with limboplasty, for reduction of developmental dysplasia of the hips after walking age. The purposes of this report were to: describe the technique of the arthroscopic procedure, and evaluate our new method using radiographic parameters. Ten patients with ten hips with developmental dysplasia after walking age treated by arthroscopic reduction with limboplasty were included in this study. The mean age of the patients at reduction was 22.6 months (range, 18.6-29.7 months); mean age at follow up was 7.2 years (range, 3.9-10.9 years); and mean follow up was 5.4 years (range, 1.7-9.0 years). These ten hips were evaluated using radiographic measurements. Moderate or severe avascular necrosis of the femoral head was not observed. Two hips that had a spherical-shaped head with minimal residual height loss or coxa magna were classified as Kalamchi and MacEwen grade 1. Additional surgery had been performed for two hips classified as Severin group 4 during the course of follow up. These two hips were classified as Severin group 1 at final examination. One more hip was classified as Severin group 4 at final examination, and additional surgery was recommended. The remaining seven hips (70%) therefore obtained good evaluations by arthroscopic reduction with limboplasty alone. We developed a new reduction method by using an arthroscopic procedure for the reduction of developmental dysplasia of the hips after walking age when this dysplasia failed to be reduced

  4. Aplicação do delineamento simplex-centroide no estudo da cinética da oxidação de biodiesel B100 em mistura com antioxidantes sintéticos The simplex-centroid design applied to study of the kinetics of the oxidation of B100 biodiesel in blend with synthetic antioxidants

    Dionísio Borsato; Luiz Henrique Dall'Antonia; Carmen Luísa B. Guedes; Elaine Cristina R. Maia; Heverson Renan de Freitas; Ivanira Moreira; Kelly Roberta Spacino

    2010-01-01

    Antioxidants are an alternative to prevent or slow the degradation of the biofuel. In this study, it was evaluated the oxidative stability of B100 biodiesel from soybean oil in the presence of three commercial synthetic antioxidants, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and tert-butylhydroquinone (TBHQ), pure or blended, from the experimental design of simplex-centroid mixture. The reaction order and rate constant were also calculated for all tests. The treatment con...

  5. Determination of Critical Slip Surface of Soil Slope by New Complex Method

    Li Liang; Chi Shichun; Lin Gao

    2006-01-01

    A new complex method is presented considering not only the improvement upon the "bad "design point, but also the diversity of the newly generated complex, which is obtained by replacing the "bad "design point with the better design point located at the line between the "bad "design point and the centroid of the remaining design points of the old complex. The new complex method is apphed to searching for the critical slip surface of two non-homogeneous soil slopes. The comparison of the results obtained by the new complex method with that by the basic complex method shows that the new complex method is much more likely to find the true critical surface for the randomly generated initial complex.

  6. On Methods of Finding Water in the Karst Zones of Southwest China%西南岩溶地区找水技术方法探讨

    李伟; 朱庆俊; 王洪磊; 李戍

    2011-01-01

    In the karst zones of Southwest China,groundwater is mainly stored in karst caves,karst channels and fractures.Karst water exploration is extremely difficult due to the heterogeneity of karst development and mud-filling in the shallow subsurface,which is not favorable to solve the problem of drinking water shortage for local people and livestock.In the work practice of fighting a drought and finding water in Long'an County,we estimated the location of water-bearing structure on the basis of geographic and geomorphic conditions,formation lithology,distribution of ponors and spring spots,then determined a target range for finding water.Furthermore,we described the spatial characters and watery property of ground water reservoirs in terms of resistivity response of water-bearing structure and hydrogeological information.In practice,we summarized the methods of mapping low resistivity in the high-resistivity area and high resistivity in the low-resistivity area to determine the well locations,which avoided the problem of mudstone filling,and increased the well completion ratio.%我国西南岩溶地区的地下水主要赋存于溶洞、管道和裂隙中,由于岩溶发育的不均匀性及其浅部的泥质充填,给岩溶水的勘查和开发带来了极大的困难,造成了当地人畜饮用水严重缺乏。在广西隆安县抗旱找水工作实践中,根据地形地貌、地层岩性、落水洞及泉点的分布等情况分析推断储水构造的位置,确定找水靶区;进而依据储水构造的电性特征结合水文地质调查结果,刻画储水构造的空间发育特征及其富水性。工作中总结的高阻中找低阻、低阻中找高阻的找水定井经验,有效避开了储水构造中泥质充填,提高了工作效率和成井率。

  7. Combined radioimmunoassay of 17-alpha-hydroxyprogesterone and 11-desoxycortisol, and of dehydroepiandrosterone-sulphate: Methods and some novel clinical findings

    The radioimmunoassay (RIA) methods for determining 17-alpha-hydroxyprogesterone (17HOP), 11-desoxycortisol (Cpd.-S), and dehydroepiandrosterone-sulphate, are reported. The plasma levels of these hormones were measured in a series of 15 diagnostic groups including adrenal diseases, fertility-related problems and human growth hormone (HGH) deficiency states. The relations of DHEA-S and growth hormone were studied in a group of children with growth retardation who presented an absent response to HGH stimulation tests. The DHEA-S level found in these patients was significantly lower than that of their age-matched controls. Furthermore, in an etiologically different entity, i.e. head-injury patients, similar findings were also made. In a single case with HGH deficiency due to antibodies against HGH, DHEA-S levels were not detectable. It is suggested that the determination of DHEA-S plasma levels can provide further insight into the classification of patients with fertility-related problems. Furthermore, it appears that DHEA-S can be taken as an indicator for the availability of bioactive human growth hormone. The various forms of congenital adrenal hyperplasia (CAH) can be successfully screened and detected by the determination of the plasma levels of 17-alpha-hydroxyprogesterone (17HOP), of 11-desoxycortisol (Cpd.-S), and of dehydroepiandrosterone-sulphate (DHEA-S). These tests are also relevant in the investigation of patients with hirsutism, hyperandrogenism, and amenorrhea. RIA procedures for the measurement of these hormones are described and new clinical data on DHEA-S are presented in relation to fertility problems both in men and women, such as oligozoospermia, oligomenorrhea and aspermia and, in cases of human growth hormone (HGH), deficiency states such as retarded growth, head-injury patients and, in one case, HGH deficiency due to antibodies directed against HGH. The relations between normo- and hyperprolactinaemia and DHEA-S are also examined

  8. Challenges from Tuberculosis Diagnosis to Care in Community-Based Active Case Finding among the Urban Poor in Cambodia: A Mixed-Methods Study.

    Natalie Lorent

    Full Text Available While community-based active case finding (ACF for tuberculosis (TB holds promise for increasing early case detection among hard-to-reach populations, limited data exist on the acceptability of active screening. We aimed to identify barriers and explore facilitators on the pathway from diagnosis to care among TB patients and health providers.Mixed-methods study. We administered a survey questionnaire to, and performed in-depth interviews with, TB patients identified through ACF from poor urban settlements in Phnom Penh, Cambodia. Additionally, we conducted focus group discussions and in-depth interviews with community and public health providers involved in ACF, respectively.Acceptance of home TB screening was strong among key stakeholders due to perceived reductions in access barriers and in direct and indirect patient costs. Privacy and stigma were not an issue. To build trust and facilitate communication, the participation of community representatives alongside health workers was preferred. Most health providers saw ACF as complementary to existing TB services; however, additional workload as a result of ACF was perceived as straining operating capacity at public sector sites. Proximity to a health facility and disease severity were the strongest determinants of prompt care-seeking. The main reasons reported for delays in treatment-seeking were non-acceptance of diagnosis, high indirect costs related to lost income/productivity and transportation expenses, and anticipated side-effects from TB drugs.TB patients and health providers considered home-based ACF complementary to facility-based TB screening. Strong engagement with community representatives was believed critical in gaining access to high risk communities. The main barriers to prompt treatment uptake in ACF were refusal of diagnosis, high indirect costs, and anticipated treatment side-effects. A patient-centred approach and community involvement were essential in mitigating barriers

  9. H.U.B city steps: methods and early findings from a community-based participatory research trial to reduce blood pressure among african americans

    Molaison Elaine

    2011-06-01

    Full Text Available Abstract Background Community-based participatory research (CBPR has been recognized as an important approach to develop and execute health interventions among marginalized populations, and a key strategy to translate research into practice to help reduce health disparities. Despite growing interest in the CBPR approach, CBPR initiatives rarely use experimental or other rigorous research designs to evaluate health outcomes. This behavioral study describes the conceptual frameworks, methods, and early findings related to the reach, adoption, implementation, and effectiveness on primary blood pressure outcomes. Methods The CBPR, social support, and motivational interviewing frameworks are applied to test treatment effects of a two-phased CBPR walking intervention, including a 6-month active intervention quasi experimental phase and 12-month maintenance randomized controlled trial phase to test dose effects of motivational interviewing. A community advisory board helped develop and execute the culturally-appropriate intervention components which included social support walking groups led by peer coaches, pedometer diary self-monitoring, monthly diet and physical activity education sessions, and individualized motivational interviewing sessions. Although the study is on-going, three month data is available and reported. Analyses include descriptive statistics and paired t tests. Results Of 269 enrolled participants, most were African American (94% females (85% with a mean age of 43.8 (SD = 12.1 years. Across the 3 months, 90% of all possible pedometer diaries were submitted. Attendance at the monthly education sessions was approximately 33%. At the 3-month follow-up 227 (84% participants were retained. From baseline to 3-months, systolic BP [126.0 (SD = 19.1 to 120.3 (SD = 17.9 mmHg; p Conclusions This CBPR study highlights implementation factors and signifies the community's active participation in the development and execution of this study. Reach

  10. Movements of the Western Pacific Warm Pool Centroid and Their Relationship to Sea Surface Temperature Changes in Ni(n)o Regions

    FANG Mingqiang

    2005-01-01

    By using monthly historical sea surface temperature (SST) data for the years from 1950 to 2000, the Western Pacific Warm Pool (WPWP) climatology and anomalies are studied in this paper. The analysis of WPWP centroid (WPWPC)movement anomalies and the Nino-3 region SST anomalies(SSTA) seems to reveal a close, linear relation between the zonal WPWPC and Nino-3 region SSTA, which suggests that a 9° anomaly of the zonal displacement from the climatological position of the WPWPC corresponds to about a 1℃ anomaly in the Nino-3 region area-mean SST. This study connects the WPWPC zonal displacement with the Nino-3 SSTA, and it may be helpful in better understanding the fact that the WPWP eastward extension is conducive to the Nino-3 region SST increase during an El Nino-Southern Oscillation (ENSO) event.

  11. 格点形心问题的若干结果%Some Results on the Lattice-Point Centroid Problem

    王晓凯

    2002-01-01

    Let n(k) be the smallest integer n such that, given any n lattice points in the plane,some k of them have a lattice-point centroid. Erickson posted an open problem on determining n(4) in [4]. This note gives an answer that n(4) = 13. Furthermore, some related results are presented.%设n(k)为满足如下条件的最小整数:给定平面上任意n个格点,其中必存在k个点的形心也是格点.文献[4]提出关于确定n(4)的未解问题.本文给出解答n(4)=13,并进一步给出相关的一些问题的结果.

  12. Reliability of an experimental method to analyse the impact point on a golf ball during putting.

    Richardson, Ashley K; Mitchell, Andrew C S; Hughes, Gerwyn

    2015-06-01

    This study aimed to examine the reliability of an experimental method identifying the location of the impact point on a golf ball during putting. Forty trials were completed using a mechanical putting robot set to reproduce a putt of 3.2 m, with four different putter-ball combinations. After locating the centre of the dimple pattern (centroid) the following variables were tested; distance of the impact point from the centroid, angle of the impact point from the centroid and distance of the impact point from the centroid derived from the X, Y coordinates. Good to excellent reliability was demonstrated in all impact variables reflected in very strong relative (ICC = 0.98-1.00) and absolute reliability (SEM% = 0.9-4.3%). The highest SEM% observed was 7% for the angle of the impact point from the centroid. In conclusion, the experimental method was shown to be reliable at locating the centroid location of a golf ball, therefore allowing for the identification of the point of impact with the putter head and is suitable for use in subsequent studies. PMID:26102559

  13. Aplicação do delineamento simplex-centroide no estudo da cinética da oxidação de biodiesel B100 em mistura com antioxidantes sintéticos The simplex-centroid design applied to study of the kinetics of the oxidation of B100 biodiesel in blend with synthetic antioxidants

    Dionísio Borsato

    2010-01-01

    Full Text Available Antioxidants are an alternative to prevent or slow the degradation of the biofuel. In this study, it was evaluated the oxidative stability of B100 biodiesel from soybean oil in the presence of three commercial synthetic antioxidants, butylated hydroxyanisole (BHA, butylated hydroxytoluene (BHT and tert-butylhydroquinone (TBHQ, pure or blended, from the experimental design of simplex-centroid mixture. The reaction order and rate constant were also calculated for all tests. The treatment containing pure TBHQ proved to be the most effective, proven by design, the optimum mix obtained and the rate constant. Binary and ternary mixtures containing TBHQ also showed appreciable antioxidant effect.

  14. Splitting Methods for Convex Clustering

    Chi, Eric C.; Lange, Kenneth

    2013-01-01

    Clustering is a fundamental problem in many scientific applications. Standard methods such as $k$-means, Gaussian mixture models, and hierarchical clustering, however, are beset by local minima, which are sometimes drastically suboptimal. Recently introduced convex relaxations of $k$-means and hierarchical clustering shrink cluster centroids toward one another and ensure a unique global minimizer. In this work we present two splitting methods for solving the convex clustering problem. The fir...

  15. Effects of Hourly, Low-Incentive, and High-Incentive Pay on Simulated Work Productivity: Initial Findings with a New Laboratory Method

    Oah, Shezeen; Lee, Jang-Han

    2011-01-01

    The failures of previous studies to demonstrate productivity differences across different percentages of incentive pay may be partially due to insufficient simulation fidelity. The present study compared the effects of different percentages of incentive pay using a more advanced simulation method. Three payment methods were tested: hourly,…

  16. Radiological findings after gastrectomy

    Riedl, P.; Polterauer, P.; Funovics, J.

    1980-06-01

    In 63 patients after total gastrectomy and reconstruction of the small bowel described by Beal-Longmire, Roux and Tomoda radiological findings were correlated with clinical symptoms. No correlation could be found between clinical symptoms of dumping and oesophagitis caused by reflux on one side and increased length of intestinal transit time, increased diameter of intestinal loops and gastro-oesophageal reflux on the other side. Enlarged blind loops after termino-lateral oesophago-jejunostomy and insufficient ligations (operation technique by Tomoda) were correlated with higher incidence of pains. Patients operated by the method of Beal-Longmire and Roux showed better results than those operated with the method of Tomoda.

  17. Bridging macroscopic and microscopic methods for the measurements of cerebral blood flow: Toward finding the determinants in maintaining the CBF homeostasis.

    Kanno, I; Masamoto, K

    2016-01-01

    Methods exist to evaluate the cerebral blood flow (CBF) at both the macroscopic and microscopic spatial scales. These methods provide complementary information for understanding the mechanism in maintaining an adequate blood supply in response to neural demand. The macroscopic CBF assesses perfusion flow, which is usually measured using radioactive tracers, such as diffusible, nondiffusible, or microsphere. Each of them determines CBF based on indicator dilution principle or particle fraction principle under the assumption that CBF is steady state during the measurement. Macroscopic CBF therefore represents averaged CBF over a certain space and time domains. On the other hand, the microscopic CBF assesses bulk flow, usually measures using real-time microscopy. The method assesses hemodynamics of microvessels, ie, vascular dimensions and flow velocities of fluorescently labeled or nonlabeled RBC and plasma markers. The microscopic CBF continuously fluctuates in time and space. Smoothing out this heterogeneity may lead to underestimation in the macroscopic CBF. To link the two measurements, it is needed to introduce a common parameter which is measurable for the both methods, such as mean transit time. Additionally, applying the defined physiological and/or pharmacological perturbation may provide a good exercise to determine how the specific perturbations interfere the quantitative relationships between the macroscopic and microscopic CBF. Finally, bridging these two-scale methods potentially gives a further indication how the absolute CBF is regulated with respect to a specific type of the cerebrovascular tones or capillary flow velocities in the brain. PMID:27130412

  18. Uni and multivariate methods applied to studies of phenotypic adaptability in maize (Zea mays L.)=Métodos uni e multivariados aplicados em estudos de adaptabilidade fenotípica em milho (Zea mays L.).

    Antonio Carlos Gerage; Pedro Mário de Araújo; Deoclécio Domingos Garbuglio; Esmael Lopes dos Santos; Pedro Sentaro Shioga; Cássio Egidio Cavenaghi Prete

    2011-01-01

    The objective of this study was to evaluate the performance of 15 maize cultivars in seven locations in Paraná State, Brazil. Towards this aim, grain yield trials were conducted during two crop seasons, and centroid (multivariate) and bissegmented regression (univariate) methods were used to evaluate possible divergences among results obtained. The genotypes were evaluated in randomized complete blocks with three replications. The centroid method was effective for indicating productive potent...

  19. Multiresponse optimisation on biodiesel obtained through a ternary mixture of vegetable oil and animal fat: Simplex-centroid mixture design application

    Highlights: • Mixture experimental design was used which allowed evaluating various responses. • Predictive equation was presented that allows verifying the behavior of the mixtures. • The results depicted that the obtained biodiesel dispensed the use of any additives. - Abstract: The quality of biodiesel is a determining factor in its commercialisation, and parameters such as the Cold Filter Plugging Point (CFPP) and Induction Period (IP) determine its operability in engines on cold days and storage time, respectively. These factors are important in characterisation of the final product. A B100 biodiesel formulation was developed using a multiresponse optimisation, for which the CFPP and cost were minimised, and the IP and yield were maximised. The experiments were carried out according to a simplex-centroid mixture design using soybean oil, beef tallow, and poultry fat. The optimum formulation consisted of 50% soybean oil, 20% beef tallow, and 30% poultry fat and had CFPP values of 1.92 °C, raw material costs of US$ 903.87 ton−1, an IP of 8.28 h, and a yield of 95.68%. Validation was performed in triplicate and the t-test indicated that there were no difference between the estimated and experimental values for none of the dependent variables, thus indicating efficiency of the joint optimisation in the biodiesel production process that met the criteria for CFPP and IP, as well as high yield and low cost

  20. Granulomatous mastitis: radiological findings

    Ozturk, M.; Mavili, E.; Kahriman, G.; Akcan, A.C.; Ozturk, F. [Depts. of Radiology, Surgery, and Pathology, Erciyes Univ. Medical Faculty, Kayseri (Turkey)

    2007-02-15

    Purpose: To evaluate the radiological, ultrasonographic, and magnetic resonance imaging (MRI) findings of idiopathic granulomatous mastitis. Material and Methods: Between April 2002 and June 2005, the mammography, ultrasound, color Doppler ultrasound, non enhanced MR, and dynamic MR findings of nine patients with the preliminary clinical diagnosis of malignancy and the final diagnosis of granulomatous mastitis were evaluated. Results: On mammography, asymmetrical focal densities with no distinct margins, ill-defined masses with spiculated contours, and bilateral multiple ill-defined nodules were seen. On ultrasound, in four patients a discrete, heterogenous hypoechoic mass, in two patients multiple abscesses, in one patient bilateral multiple central hypo peripheral hyperechoic lesions, in two patients heterogeneous hypo- and hyperechoic areas together with parenchymal distortion, and in one patient irregular hypoechoic masses with tubular extensions and abscess cavities were seen. Five of the lesions were vascular on color Doppler ultrasound. On MR mammography, the most frequent finding was focal or diffuse asymmetrical signal intensity changes that were hypointense on T1W images and hyperintense on T2W images, without significant mass effect. Nodular lesions were also seen. On dynamic contrast-enhanced mammography, mass-like enhancement, ring-like enhancement, and nodular enhancement were seen. The time-intensity curves differed from patient to patient and from lesion to lesion. Conclusion: The imaging findings of idiopathic granulomatous mastitis have a wide spectrum, and they are inconclusive for differentiating malignant and benign lesions.

  1. Granulomatous mastitis: radiological findings

    Purpose: To evaluate the radiological, ultrasonographic, and magnetic resonance imaging (MRI) findings of idiopathic granulomatous mastitis. Material and Methods: Between April 2002 and June 2005, the mammography, ultrasound, color Doppler ultrasound, non enhanced MR, and dynamic MR findings of nine patients with the preliminary clinical diagnosis of malignancy and the final diagnosis of granulomatous mastitis were evaluated. Results: On mammography, asymmetrical focal densities with no distinct margins, ill-defined masses with spiculated contours, and bilateral multiple ill-defined nodules were seen. On ultrasound, in four patients a discrete, heterogenous hypoechoic mass, in two patients multiple abscesses, in one patient bilateral multiple central hypo peripheral hyperechoic lesions, in two patients heterogeneous hypo- and hyperechoic areas together with parenchymal distortion, and in one patient irregular hypoechoic masses with tubular extensions and abscess cavities were seen. Five of the lesions were vascular on color Doppler ultrasound. On MR mammography, the most frequent finding was focal or diffuse asymmetrical signal intensity changes that were hypointense on T1W images and hyperintense on T2W images, without significant mass effect. Nodular lesions were also seen. On dynamic contrast-enhanced mammography, mass-like enhancement, ring-like enhancement, and nodular enhancement were seen. The time-intensity curves differed from patient to patient and from lesion to lesion. Conclusion: The imaging findings of idiopathic granulomatous mastitis have a wide spectrum, and they are inconclusive for differentiating malignant and benign lesions

  2. Management Control System and the Case of CSR in the Tunisian Industrial Companies: What Findings by the Method of Structural Equation?

    Hichem Dkhili; Hedi Noubbigh

    2013-01-01

    This study aims to the behavior of management control; it is providing a model to the behavior of integration of social responsibility in the management control tools. This model was validated with 306 Tunisian companies in the industrial sector. Through a questionnaire, the data collected are processed using exploratory and confirmatory analysis by the methods of structural equations. The results revealed that the management control system in industrial Tunisia is facing economic responsibil...

  3. Finding of experience of the use of computer-integrated forms and methods of teaching in the process of preparation of future teachers of initial school

    Sinopalnikova N.N.

    2010-06-01

    Full Text Available Theoretically grounded and experimentally examined that one of the trends of future teachers training for the integrated activity is gaining experience in using the integrated organization forms of learning. It is realized in the process of specially organized student's learning and during their pedagogical practice. It was promoted by conducting the special course The integrated forms of learning organization in primary school with the use of interactive forms and methods of learning, fulfilling the aimed tasks while passing pedagogical practice.

  4. Matrix Organization and Merit Factor Evaluation as a Method to Address the Challenge of Finding a Polymer Material for Roll Coated Polymer Solar Cells

    Bundgaard, Eva; Livi, Francesco; Hagemann, Ole;

    2015-01-01

    The results presented demonstrate how the screening of 104 light-absorbing low band gap polymers for suitability in roll coated polymer solar cells can be accomplished through rational synthesis according to a matrix where 8 donor and 13 acceptor units are organized in rows and columns. Synthesis...... silver comb back electrode structure. The matrix organization enables fast identification of active layer materials according to a weighted merit factor that includes more than simply the power conversion efficiency and is used as a method to identify the lead candidates. Based on several characteristics...

  5. A search system for optimum energy use: using the Nelder-Mead method to find the optimum operating conditions for a blast furnace

    Matsumoto, S.; Kawabe, H.; Wada, K.; Kihara, H.; Takahashi, T.; Kobayashi, Y.

    1983-01-01

    The Nelder-Mead method was used to search for optimum operating conditions (such that energy use is minimized) of a blast furnace for given production and fuel conditions. The search system is explained and its use illustrated for the case of all-coke production with zero N/sub 2/ and O/sub 2/ injection. Furnace restrictions are obtained and the blast temperature and humidity for minimum cost operation are derived on the basis of gas flow, tuyere nose temperature and furnace core temperature. (1 ref.)

  6. Semi-automatic Face Image Finding Method, Which Uses the 3D Model of the Head for Recognising an Unknown Face

    Krutikova, O; Glazs, A

    2015-01-01

    In this paper, a semi-automatic facial recognition algorithm is proposed in case of an insufficient training set (profile, front, half-turn). The recognition algorithm uses a polygonal 3D model that is created from the base images. The control points, in the proposed method, are transferred from the base images onto the 3D model, and they are also placed on the new image from the examination set. Then, the 3D model is used to determine the rotation angle of the head on th...

  7. MANAGEMENT CONTROL SYSTEM AND THE CASE OF CSR IN THE TUNISIAN INDUSTRIAL COMPANIES: WHAT FINDINGS BY THE METHOD OF STRUCTURAL EQUATION?

    Hichem Dkhili

    2013-01-01

    Full Text Available This study aims to the behavior of management control; it is providing a model to the behavior of integration of social responsibility in the management control tools. This model was validated with 306 Tunisian companies in the industrial sector. Through a questionnaire, the data collected are processed using exploratory and confirmatory analysis by the methods of structural equations. The results revealed that the management control system in industrial Tunisia is facing economic responsibility. This is in response to emerging pressures of uncertainty related to the environment, and in enrolling a strategy of domination by cost. In addition, the management control system is designed as a guidance tool actions and behaviors.

  8. Servicemembers and veterans with major traumatic limb loss from Vietnam war and OIF/OEF conflicts: Survey methods, participants, and summary findings

    Charles Maynard, PhD

    2010-08-01

    Full Text Available Care of veterans and servicemembers with major traumatic limb loss from combat theaters is one of the highest priorities of the Department of Veteran Affairs. We achieved a 62% response rate in our Survey for Prosthetic Use from 298 Vietnam war veterans and 283 servicemembers/veterans from Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF who sustained major traumatic limb loss. Participants reported their combat injuries; health status; quality of life; and prosthetic device use, function, rejection, and satisfaction. Despite the serious injuries experienced, health status was rated excellent, very good, or good by 70.7% of Vietnam war and 85.5% of OIF/OEF survey participants. However, many health issues persist for Vietnam war and OIF/OEF survey participants(respectively: phantom limb pain (72.2%/76.0%, chronic back pain (36.2%/42.1%, residual-limb pain (48.3%/62.9%, prosthesis-related skin problems (51.0%/58.0%, hearingloss (47.0%/47.0%, traumatic brain injury (3.4%/33.9%, depression (24.5%/24.0%, and posttraumatic stress disorder (37.6%/58.7%. Prosthetic devices are currently used by 78.2% of Vietnam war and 90.5% of OIF/OEF survey participants to improve function and mobility. On average, the annual rate for prosthetic device receipt is 10.7-fold higher for OIF/OEF than for Vietnam war survey participants. Findings from this cross-conflict survey identify many strengths in prosthetic rehabilitationfor those with limb loss and several areas for future attention.

  9. Feasibility of finding malignant diseases with the Ar + 501.7 nm laser line using a new blood-analysis method

    Sato, H.; Hayashi, H.; Totsuka, T.; Sugiyama, M.; Tsuchiya, S.; Takeuchi, K.; Mochida, N.

    1983-12-01

    Utilizing a new blood-analysis method which uses the interaction between an Ar + laser beam and a blood sample, it can be shown that there is a significant difference in the reflectance variation δ R between the malignant and benign blood, at 501.7 nm of the Ar + laser, under a dc magnetic field, for both human and mouse blood. For the malignant mouse-blood with leukaemia, δ R tends to be positive with the magnetic field, while for the benign blood it is negative. This is also true for the human blood. This fact is confirmed by the inverted variation of the higher order Fourier pattern obtained by the Fourier pattern analyser from the transmitted beam through the diluted sample, for the malignant and benign mouse-blood under the magnetic field.

  10. Application of Monte-Carlo method for finding of ionization and secondary emission coefficients and volt-ampere characteristics of Townsend discharge in hydrogen

    The coefficients of γ secondary cathode emission for hydrogen is determined experimentally via calculation of the ionization numbers within the gaps by the Monte-Carlo method. In this case, one calculates the ionization frequencies, the Townsend ionization coefficients (demonstrating their nonlocality), the electron drift rate, the probability of the emitted electron return to the cathode. The calculated parameters are in line with the measured ones. One studied the gaps with pd=0.37-17 Torrxcm. It is shown that just for pd within the Paschen curve minimum vicinity the observed negative differential resistance of the Townsend discharge may be associated with the reduction of the probability of the electron return to the cathode at E/N increase

  11. Form finding and analysis of extensible membranes attached to 2-D and 3-D frames intended for micro air vehicles via experimentally validated finite element methods

    Abudaram, Yaakov Jack

    This work is concerned with a new method to apply consistent and known pretension to silicone rubber membranes intended for micro air vehicles as well as an understanding in the science of developed pre-tension in membranes constrained by 2- D and 3-D frames and structures. Pre-tension has a marked effect on the static and dynamic response of membrane wings and controls the overall deflections, as such control and measurement of the membrane pre-tension is important. Two different 2-D frame geometries were fabricated to evaluate the technique. For open-cell frames, the pretension was not uniform, whereas it was for closed-cell frames. Results show developed full-field stress and strain fields as a function of membrane attachment temperature and frame geometry along with experimental iterations to prove repeatability. The membranes can be stretched to a specific pretension according to the temperature at which it adheres to frames. Strain fields in membranes attached to 3-D frames at various temperatures are modeled through FEA utilizing Abaqus to be able to predict the developed membrane deformations, stresses, and strains. Rigid frames with various curvatures are built via appropriate molds and then adhered to silicone rubber membranes and elevated to various temperatures to achieve different pre-strains for experimental validation. Additional experiments are conducted for more complex frame geometries involving both convex and concave topologies embedded within frames. Results are then compared with the Abaqus outputs to validate the accuracy of the FEA model. Highly compliant wings have been used for MAV platforms, where the wing structure is determined by some combination of carbon fiber composites and a membrane skin, adhered in between the layers of composite material. Another new technique of attaching membranes firmly on wing structures is introduced, which involves the application of a technology known as corona treatment coupled with another method of

  12. How possible is the development of an operational psychometric method to assess the presence of the 5-HTTLPR s allele? Equivocal preliminary findings

    Laszik Andras

    2010-05-01

    Full Text Available Abstract Objective The s allele of the 5-hydroxytryptamine transporter-linked promoter region (5-HTTLPR polymorphism of the serotonin transporter gene has been found to be associated with neuroticism-related traits, affective temperaments and response to selective serotonin reuptake inhibitor (SSRI treatment. The aim of the current study was to develop a psychometric tool that could at least partially substitute for laboratory testing and could predict the presence of the s allele. Methods The study included 138 women of Caucasian origin, mean 32.20 ± 1.02 years old. All subjects completed the Hungarian standardised version of the Temperament Evaluation of the Memphis, Pisa, Paris, and San Diego Autoquestionnaire (TEMPS-A instrument and were genotyped for 5-HTTLPR using PCR. The statistical analysis included the calculation of the Index of Discrimination (D, Discriminant Function Analysis, creation of scales on the basis of the above and then item analysis and calculation of sensitivity and specificity. Results Four indices were eventually developed, but their psychometric properties were relatively poor and their joint application did not improve the outcome. Conclusions We could not create a scale that predicts the 5-HTTLPR genotype with sufficient sensitivity and specificity, therefore we could not substitute a psychometric scale for laboratory genetic testing in predicting genotype, and also possibly affective disorder characterisation and treatment.

  13. Abdominal aspergillosis: CT findings

    Yeom, Suk Keu, E-mail: pagoda20@hanmail.net [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Kim, Hye Jin, E-mail: kimhyejin@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Byun, Jae Ho, E-mail: jhbyun@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Kim, Ah Young, E-mail: aykim@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Lee, Moon-Gyu, E-mail: mglee@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Ha, Hyun Kwon, E-mail: hkha@amc.seoul.kr [Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap2-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of)

    2011-03-15

    Objective: In order to retrospectively evaluate the CT findings of abdominal aspergillosis in immunocompromised patients. Materials and methods: CT scans were reviewed with regard to the sites, number, morphologic appearance, attenuation, and the contrast enhancement patterns of the lesions in six patients (5 women, 1 man; mean age, 43.4 years; range, 23-59 years) with pathologically proved abdominal aspergillosis by two gastrointestinal radiologists in consensus. Medical records were also reviewed to determine each patient's clinical status and outcome. Results: All patients were immunocompromised state: 4 patients received immunosuppressive therapy for solid organ transplantation and 2 patients received chemotherapy for acute myeloid leukemia. Aspergillosis involved blood vessels (n = 3), liver (n = 2), spleen (n = 2), gastrointestinal tract (n = 2), native kidney (n = 1), transplanted kidney (n = 1), peritoneum (n = 1), and retroperitoneum (n = 1). CT demonstrated solid organ or bowel infarction or perforation secondary to vascular thrombosis or pseudoaneurysm, multiple low-attenuating lesions of solid organs presenting as abscesses, concentric bowel wall thickening mimicking typhlitis, or diffuse or nodular infiltration of the peritoneum and retroperitoneum. Conclusion: Familiarity with findings commonly presenting as angioinvasive features or abscesses on CT, may facilitate the diagnosis of rare and fatal abdominal aspergillosis.

  14. Radiological findings in angiofibroma

    Surgery after pre-operative embolization has become the main treatment modality in angiofibroma therapy. As surgical planning is based on precise pre-operative tumour evaluation, knowledge of the characteristic growth patterns is of great interest. Analysis of tumour extension and blood supply, as well as methods of controlling intra-operative bleeding, help in determining the appropriate surgical approach. Though benign, angiofibroma demonstrates a locally aggressive nature. This fibrovascular tumour is characterised by typical radiological findings and by predictable growth patterns. The tumour extension and blood supply can be accurately determined by CT, MR imaging and angiography. With classic radiological findings, no pre-operative biopsy is necessary in most angiofibromas. Advances in radiological imaging have contributed to improved surgical planning and tumour resection. The surgeon is able to select the least traumatic approach with secure haemostatic control, which is also critical for avoiding the disturbance of facial skeletal growth in this group of young patients. Embolization, pre-operative autologous donation and the cell saver system for immediate retransfusion of the collected blood after filtration, are important tools for dealing with blood loss in angiofibroma surgery as they minimize homologous blood transfusion

  15. Abdominal aspergillosis: CT findings

    Objective: In order to retrospectively evaluate the CT findings of abdominal aspergillosis in immunocompromised patients. Materials and methods: CT scans were reviewed with regard to the sites, number, morphologic appearance, attenuation, and the contrast enhancement patterns of the lesions in six patients (5 women, 1 man; mean age, 43.4 years; range, 23-59 years) with pathologically proved abdominal aspergillosis by two gastrointestinal radiologists in consensus. Medical records were also reviewed to determine each patient's clinical status and outcome. Results: All patients were immunocompromised state: 4 patients received immunosuppressive therapy for solid organ transplantation and 2 patients received chemotherapy for acute myeloid leukemia. Aspergillosis involved blood vessels (n = 3), liver (n = 2), spleen (n = 2), gastrointestinal tract (n = 2), native kidney (n = 1), transplanted kidney (n = 1), peritoneum (n = 1), and retroperitoneum (n = 1). CT demonstrated solid organ or bowel infarction or perforation secondary to vascular thrombosis or pseudoaneurysm, multiple low-attenuating lesions of solid organs presenting as abscesses, concentric bowel wall thickening mimicking typhlitis, or diffuse or nodular infiltration of the peritoneum and retroperitoneum. Conclusion: Familiarity with findings commonly presenting as angioinvasive features or abscesses on CT, may facilitate the diagnosis of rare and fatal abdominal aspergillosis.

  16. Radiological findings in angiofibroma

    Schick, B. [Univ. of Marburg (Germany). Dept. of Ear, Nose and Throat Diseases; Kahle, G. [Univ. of Marburg, (Germany). Inst.of Radiology

    2000-11-01

    Surgery after pre-operative embolization has become the main treatment modality in angiofibroma therapy. As surgical planning is based on precise pre-operative tumour evaluation, knowledge of the characteristic growth patterns is of great interest. Analysis of tumour extension and blood supply, as well as methods of controlling intra-operative bleeding, help in determining the appropriate surgical approach. Though benign, angiofibroma demonstrates a locally aggressive nature. This fibrovascular tumour is characterised by typical radiological findings and by predictable growth patterns. The tumour extension and blood supply can be accurately determined by CT, MR imaging and angiography. With classic radiological findings, no pre-operative biopsy is necessary in most angiofibromas. Advances in radiological imaging have contributed to improved surgical planning and tumour resection. The surgeon is able to select the least traumatic approach with secure haemostatic control, which is also critical for avoiding the disturbance of facial skeletal growth in this group of young patients. Embolization, pre-operative autologous donation and the cell saver system for immediate retransfusion of the collected blood after filtration, are important tools for dealing with blood loss in angiofibroma surgery as they minimize homologous blood transfusion.

  17. Glossopharyngeal neuralgia: MR findings

    Objective: To investigate the possibility of MRI on visualizing the relationship between glossopharyngeal nerve and surrounding vessels, and to evaluate the significance of MRI in the diagnosis and treatment of glossopharyngeal neuralgia. Methods: MRI findings were analyzed retrospectively in 12 patients with glossopharyngeal neuralgia, and were compared with surgical findings and effect of pain relief. Results: The artery compression or contact of the glossopharyngeal entry zone, as revealed during operation in 10 patients with glossopharyngeal neuralgia, was visualized on MRI in 9 and not seen in 1. The venous compression of the glossopharyngeal entry zone was not identified on MRI in 1. The conglutinative arachnoids of the glossopharyngeal entry, zone was not visualized on MRI in 1. MRI demonstrated the affected glossopharyngeal nerve root entry zone was compressed or contacted by the posterior inferior cerebellar artery. (PICA) in 8 patients and by the vertebral artery in 1 patient. One patient's offending vessel was confirmed to be the anterior inferior cerebellar artery (AICA) by the operation, and the surgical findings were corresponded with MRI in others. Vascular compression or' contact of the affected glossopharyngeal nerve was not visualized on MRI in 3 patients, and operation confirmed that the glossopharyngeal nerve root entry zone was compressed by unknown artery in 1, by small vein in 1, and by conglutinative arachnoids in 1, respectively. Eight patients presented with symptoms of the ipsilateral trigeminal neuralgia concurrently. The compression of the affected trigeminal nerve root by superior cerebellar artery (SCA) was visualized on MRI in 6 patients, and operation did not reveal the source of artery compression in 1 and corresponded with MRI findings in other 5 cases. Vascular compression of affected trigeminal nerve was not visualized on MRI in 2 patients, and intraoperative inspection revealed that trigeminal nerve root was compressed by

  18. Finding Cryptography in Object Code

    Jason L. Wright

    2008-10-01

    Finding and identifying Cryptography is a growing concern in the malware analysis community. In this paper, a heuristic method for determining the likelihood that a given function contains a cryptographic algorithm is discussed and the results of applying this method in various environments is shown. The algorithm is based on frequency analysis of opcodes that make up each function within a binary.

  19. Fabrication Aware Form-finding

    Egholm Pedersen, Ole; Larsen, Niels Martin; Pigram, Dave;

    2014-01-01

    This paper describes a design and construction method that combines two distinct material systems with fabrication aware form-finding and file-to-factory workflows. The method enables the fluent creation of complex materially efficient structures comprising high populations of geometrically unique...

  20. MRI finding of hemangioblastomas

    Park, Seung Cheol; Oh, Min Cheol; Chung, Hwan Hoon; Seol, Hye Young; Lee, Nam Joon; Kim, Jung Hyuk [Korea University College of Medicine, Seoul (Korea, Republic of)

    1994-05-15

    The purpose of this study is to evaluate the findings of magnetic resonance imaging (MRI) of posterior fossa hemanangioblastoma and usefulness of contrast enhancement with Gd-DTPA. Seven patients with posterior fossa hemangioblastoma were studied with both pre- and post-enhanced MRI. The MR images were reviewed regarding the location, size, signal intensities of cysts and mural nodules, and their contrast enhancement pattern. Five tumors were located in cerebellar hemisphere, one in vermis, and one in posterior part of medulla. One patient with von Hippel-Lindau disease had a medullary hemangioblastoma with multiple pancreatic cysts. In 6 cases, the major portion of the tumor was cysts and had small mulkal nodules. The solid portion was relatively lange in one cases, cemprising half of the tumor cysts were oval shaped and their sized were 3-6.7 cm in diameter. In five cases(71%), septations were noted within the cysts. Cysts were isointense or slightly hyperintense on T1-weighted image and hyperintense on T2- weighted image compared with cerebrospinal fluid. Mural nodules were oval or rounded radiotherapy had better prognosis than those treated with radiotherapy alwas 0.5-2.5 cm in diameter. Mural nodules were isointense to gray matter. They were detected in five cases on T1-weighted images and one case on T2-weighted images. In two cases, vascular signal void area was noted in mural nodules. On contrast-enhanced T1-weighted images, all mural nodules were intensely enhanced. MRI provide to be a good diagnostic method to detect and characterize posterior fossa hemangioblastoma. The most common finding is Cystic posterior fossa lesion with enhancing mural nodule. Contrast enhancement is essential for specific diagnosis.

  1. MUSIC测向算法的虚假谱峰消除方法研究%Study on Method of Eliminating Spurious Spectral Peak of MUSIC Direction Finding Algorithm

    王仁涛; 李斌; 王毅

    2012-01-01

    在基于均匀线阵的MUSIC测向算法中,单元间距与波长之比大于0.5时,可能会出现虚假谱峰,干扰真实波达方向的判断。现有的一些消除虚假谱峰的方法多适用于主动测向或非均匀阵列,而对被动测向和均匀阵列无法适用。针对这一问题,本文通过分析虚假谱峰的出现原因,提出一种新的通过机械旋转进行虚假谱峰消除的方法——阵列旋转法,并仿真分析验证了该方法的有效性。该方法实现简单,适用范围广,能较好满足实际工程设计需求。%In the MUSIC direction finding algorithm based on uniform linear array, when the ratio of the element spacing to wavelength is more than 0. 5, the spurious spectral peak may occur to interfere direction of real arrival estimation. The available methods of eliminating spurious spectral peak are mainly suitable for active direction find- ing or non-uniform array, not for passive direction finding and uniform array. Aiming at this issue, a novel method of eliminating spurious spectral peak ( array rotating method) by mechanical rotating after analyzing causes for occurrence of spurious spectral peak is presented. The simulated results show effectiveness of this method. The implementation of this method is simply, and it can be widely applied and meet real engineering design requirement.

  2. A Two-Stage Method for Scientific Papers Analysis

    Damien Hanyurwimfura

    2014-10-01

    Full Text Available A considerable amount of research is being conducted by many people (researchers, graduate students, professors etc everyday. Finding information about aspecific topic is one of the most time consuming activities of those people. People doing research have to search, read and analyze multiple research papers, e-books and other documents and then determine what they contain and discover knowledge from them. Many available resources are in the form of unstructured text format of long text pages which require long time to read and analyze. In this paper we propose a two-stage method for scientific paper analysis. The method uses information extraction to extract the main idea key sentences (mainly needed by the most readers from the paper and the extracted paper’s information is then organized in a structured format and grouped in different clusters according to their topics using a multi-word based clustering method. The proposed method combines different features in paper’s topics extraction and uses multi-word matching feature in selection of initial centroids for clustering. The proposed method can help readers to access and analyze multiple research papers documents timely and efficiently. Conducted experiments show the effectiveness and usefulness of our proposed approach.

  3. Radiologic findings of sacroiliitis : emphasis on MR findings

    Yang, Ik; Park, Hai Jung; Lee, Yul; Chung, Soo Young; Park, Jong Ho [Hallym Univ. College of Medicine, Chunchon (Korea, Republic of)

    1997-05-01

    To compare the characteristic MR findings of infectious sacroiliitis (IS) and ankylosing spondylitis (AS). We retrospectively reviewed MR findings in eight patients with IS (pyogenic in six, tuberculosis in two) confirmed by culture and clinical follow-up, and in six with AS by HLA-B27 typing. AA control group of 13 asymptomatic volunteers was formed, and they underwent MRI Findings were analysed for morphology, degree of bone erosion, and adjacent soft tissue change. CT findings of AS in four patients and IS in four were also compared to MR findings. MR characteristics of IS included unilaterality (100%), abnormal cartilage signal intensity (100%), bone marrow change (100%), contrast enhancement (100%), erosion (63%), and soft tissue change (63%). MR findings of AS showed bilaterality (67%), abnormal cartilage signal intensity (80%), bone marrow change (80%), erosion (80%), contrast enhancement (44%) and soft tissue change (10%). CT scan showed bony sclerosis and erosion (86%), and abnormal joint space (71%). MR findings of sacroiliitis were loss of thin zone of a cartilage and erosions on T1-weighted image, and increased signal intensity on T2-weighted image. MRI is regarded as a useful diagnostic method where conventional diagnosis is difficult, and is able to image cartilage abnormalities directly and noninvasively. Significant differences in MR findings between IS and AS were not noted, however.

  4. Azimuth Computation Method Study on Remote Direction Finding Based on Gauss-Krueger Projection%高斯-克吕格投影的远程测向方位角计算方法

    王锐; 徐祎; 王晓翔; 姜丽; 柏诗玉

    2013-01-01

      唯一参考点单目标计算方位角的经典方法计算唯一参考点多目标之间的方位角时,方位角方向线由于地球曲率影响通常不在同一平面,在远程测向中尤为明显。为此提出了一种基于高斯-克吕格投影的远程测向方位角计算方法,利用高斯-克吕格投影及三度分带法,将地球近似椭球体转化为二维平面,再进行远程方位角计算。该算法减小了地球曲率影响,提高了计算精度。通过具有代表性的几组数据的验证说明本算法的有效性。可用在无线电波远程测向定位、航海航空计算等领域。%At azimuth computation between multiple targets with one reference point by the classic method applied in the azimuth computation between one reference point and single target,the azimuth direction vectors are non-coplanar influenced by earth curvature,which is especially obvious in remote direction finding. In this paper it is put forward that azimuth computation method on remote direction finding based on Gauss-Krueger projection,which is that the earth approximate ellipsoid is transformed into two-dimensional plane to compute remote azimuth with. Gauss-Krueger projection and 3°zone dividing. This method has less earth curvature effect and higher accuracy than the classic method. In this paper azimuth computation with several groups of representative datum verifies the effective of the method in remote direction finding,and the method can be used in radio remote goniometric location, navigation and aviation computation.

  5. A FAST FORM-FINDING METHOD FOR SINGLE-LAYER PLANE CABLE NET WITH ELASTIC BOUNDARY%一种弹性边界单层平面索网快速找形方法

    林晖; 吴杰; 罗晓群; 张其林

    2015-01-01

    Single‐layer cable net glass curtain is an advanced technique that has been widely used in public buildings .Configuration and cable force of initial state can be significantly affected by boundary deformation in cable net .A fast form‐finding method was presented in this paper ,it was a nonlinear iteration method based on unstressed length control method .Compared with ANSYS ,this method was proved to be high efficiency and good accuracy . The correctness of this method was also verified by backward and forward analysis .Error analysis showed that cable force error is bigger in unstressed length control method ,but geometric error is smaller .Cable force control method ,by contrast ,has bigger geometric error and smaller cable force error .%单层平面索网玻璃幕墙结构是广泛应用于大型公共建筑中的一种新型结构形式。针对弹性边界索网中边界变形会显著影响索网初始状态的位形和索力的特点,提出并实现一种快速找形方法,即基于原长法的非线性迭代方法,其与ANSYS的对比分析表明,该方法计算效率高、找形结果精确。同时,通过倒拆和正装分析验证了该方法的正确性。施工过程误差分析表明,定长控制施工法的索力误差较大,但几何误差较小,主动索力控制法则相反。

  6. Thoracic textilomas: CT findings

    Objective: the aim of this study was to analyze chest CT scans of patients with thoracic textiloma. Methods: this was a retrospective study of 16 patients (11 men and 5 women) with surgically confirmed thoracic textiloma. The chest CT scans of those patients were evaluated by two independent observers, and discordant results were resolved by consensus. Results: the majority (62.5%) of the textilomas were caused by previous heart surgery. The most common symptoms were chest pain (in 68.75%) and cough (in 56.25%). In all cases, the main tomographic finding was a mass with regular contours and borders that were well-defined or partially defined. Half of the textilomas occurred in the right hemithorax and half occurred in the left. The majority (56.25%) were located in the lower third of the lung. The diameter of the mass was ≤ 10 cm in 10 cases (62.5%) and > 10 cm in the remaining 6 cases (37.5%). Most (81.25%) of the textilomas were heterogeneous in density, with signs of calcification, gas, radiopaque marker, or sponge-like material. Peripheral expansion of the mass was observed in 12 (92.3%) of the 13 patients in whom a contrast agent was used. Intraoperatively, pleural involvement was observed in 14 cases (87.5%) and pericardial involvement was observed in 2 (12.5%). Conclusions: it is important to recognize the main tomographic aspects of thoracic textilomas in order to include this possibility in the differential diagnosis of chest pain and cough in patients with a history of heart or thoracic surgery, thus promoting the early identification and treatment of this postoperative complication. (author)

  7. Thoracic textilomas: CT findings

    Machado, Dianne Melo; Zanetti, Glaucia; Araujo Neto, Cesar Augusto; Nobre, Luiz Felipe; Meirelles, Gustavo de Souza Portes; Silva, Jorge Luiz Pereira e; Guimaraes, Marcos Duarte; Escuissato, Dante Luiz; Souza Junior, Arthur Soares; Hochhegger, Bruno; Marchiori, Edson, E-mail: edmarchiori@gmail.com [Hospital Universitario Antonio Pedro (HUAP/UFF), Niteroi, RJ (Brazil)

    2014-09-15

    Objective: the aim of this study was to analyze chest CT scans of patients with thoracic textiloma. Methods: this was a retrospective study of 16 patients (11 men and 5 women) with surgically confirmed thoracic textiloma. The chest CT scans of those patients were evaluated by two independent observers, and discordant results were resolved by consensus. Results: the majority (62.5%) of the textilomas were caused by previous heart surgery. The most common symptoms were chest pain (in 68.75%) and cough (in 56.25%). In all cases, the main tomographic finding was a mass with regular contours and borders that were well-defined or partially defined. Half of the textilomas occurred in the right hemithorax and half occurred in the left. The majority (56.25%) were located in the lower third of the lung. The diameter of the mass was ≤ 10 cm in 10 cases (62.5%) and > 10 cm in the remaining 6 cases (37.5%). Most (81.25%) of the textilomas were heterogeneous in density, with signs of calcification, gas, radiopaque marker, or sponge-like material. Peripheral expansion of the mass was observed in 12 (92.3%) of the 13 patients in whom a contrast agent was used. Intraoperatively, pleural involvement was observed in 14 cases (87.5%) and pericardial involvement was observed in 2 (12.5%). Conclusions: it is important to recognize the main tomographic aspects of thoracic textilomas in order to include this possibility in the differential diagnosis of chest pain and cough in patients with a history of heart or thoracic surgery, thus promoting the early identification and treatment of this postoperative complication. (author)

  8. MEMS AO for Planet Finding

    Rao, Shanti; Wallace, J. Kent; Shao, Mike; Schmidtlin, Edouard; Levine, B. Martin; Samuele, Rocco; Lane, Benjamin; Chakrabarti, Supriya; Cook, Timothy; Hicks, Brian; Jung, Paul

    2008-01-01

    This slide presentation reviews a method for planet finding using microelectromechanical systems (MEMS) Adaptive Optics (AO). The use of a deformable mirror (DM) is described as a part of the instrument that was designed with a nulling interferometer. The strategy that is used is described in detail.

  9. Finding solution by Tabu search

    Ratanamanee, W.

    2003-11-01

    Full Text Available In this paper, the method of finding the solution by Tabu search is addressed. Tabu search is one of the local search heuristics, which has been applied extensively in operations research works. In this paper, the basic concepts of the Tabu search heuristic and some examples of applying this search technique in operations research problems are presented.

  10. A novel method of spectrum stabilization

    A new type of spectrum stabilizer for a scintillation spectrometer is described. A pulse light source DM 160 is used to introduce an artificial peak in the spectrum at a convenient energy. The centroid of pulse spectrum corresponding to artificial peak is compared with that of suitable reference pulses obtained from the DM 160 driver circuit. Any drift in artificial peak produces a d.c. voltage at the output of centroid comparator and this voltage is used to control the gain of variable gain amplifier to counter the drift. With suitable adjustment the effect of any variation in pulse height of DM 160 driving pulse can be compensated so that the spectrometer gain is independent of any variation, drift etc. in the height of pulse driving DM 160 tube. This circuit is simple and gives improved performance compared to 2 channel method of obtaining the control voltage for variable gain amplifier. (author)

  11. Fact Finding Nuclear Energy; Fact Finding Kernenergie

    Scheepers, M.J.J.; Seebregts, A.J.; Lako, P. [ECN-Beleidsstudies, Petten (Netherlands); Blom, F.J.; Van Gemert, F. [Sociaal-Economische Raad SER, Den Haag (Netherlands)

    2007-09-15

    Facts and figures on nuclear energy are presented to enable a discussion on the role of nuclear power in the transition to a sustainable energy supply for the Netherlands. The following issues are presented: Nuclear technology, safety and security (including non-proliferation and protection against terrorism); Environmental aspects (including greenhouse gas emissions of the nuclear energy lifecycle); Nuclear power and the power market (including impact of nuclear power on electricity market prices); Economic aspects (including costs of nuclear power and external costs and benefits); Policy issues (including sustainable development); Social acceptance of nuclear energy; Knowledge infrastructure for nuclear energy in the Netherlands; and Nuclear power in long term energy scenarios for the Netherlands and Europe. Using two long-term energy scenarios the report also presents a social impact analysis of an increasing share of nuclear power in the Dutch electricity supply. [Dutch] In dit onderzoek zijn feiten en gegevens over kernenergie verzameld op basis van bestaande inzichten en een veelheid aan literatuur (fact finding). Voor technologische expertise heeft ECN zich laten bijstaan door de Nucleair Research and consultancy Group (NRG). Op basis van de fact-finding studie bereidt de SER een advies voor over de rol van kernenergie in de toekomstige nationale elektriciteitsproductie. In de eerste acht hoofdstukken worden feiten en gegevens gepresenteerd over verschillende onderwerpen die bij kernenergie van belang zijn. In Hoofdstuk 2 wordt de kernenergietechnologie beschreven, inclusiefde veiligheid van kernenergie besproken, omdat die nauw met de technologie samenhangt. Hierbij gaat het om de technische veiligheid van de installaties, maar ook om beveiliging tegen misbruik van technologie en nucleair materiaal, waaronder beveiliging tegen terrorisme. De milieuaspecten door radioactiviteit en door emissies van kooldioxide die met het gebruik van kernenergie samenhangen

  12. Radiologic findings of anthracofibrosis

    To evaluate the CT findings of bronchial anthracofibrosis. Fourteen patients with bronchoscopically confirmed anthracofibrosis were involved in this study. CT findings (n=3D12) were retrospectively analysed; the pattern, distri-bution and extent of bronchial and parenchymal abnormalities and additional findings such as mediastinal lymphadenopathy and pleural effusion were assessed. Age, sex, and occupational and disease history were history were also reviewed. Patients were aged between 63 and 95 (mean, 71.3) years, and ten were female. Only one patient had an occupational history, but four had a history of pulmonary tuberculosis. Frequent radiologic findings were bronchial wall thickening(n=3D6), atelectasis(n=3D8), mediastinal lymphad-enopathy(n=3D7) and mass(n=3D4). Other accompanying findings were bronchial wall calcification(n=3D3), consolidation(n=3D2) and pleural effusion(n=3D2). Right upper (n=3D7) and right middle lobe(n=3D7) were the most commonly involved sites, and multifocal involvement (n=3D7) was frequent. Bronchial wall thickening, atelectasis and mediastinal lymphadenopathy were characteristic CT findings of anthracofibrosis. When such findings are noted in older or aged female patients, anthracofibrosis should be included in the differential diagnosis

  13. A comparison of methods for calculating population exposure estimates of daily weather for health research

    Dear Keith BG

    2006-09-01

    appropriate method conceptually is the use of weather data from sites within 50 kilometres radius of the area weighted to population centres, but a simpler acceptable option is to weight to the geographic centroid.

  14. Find a Therapist

    ... Facts Find Help News and Research Tips for Soldiers and Veterans Tips for Families and Friends Take ... questions to ask for yourself and for your child . If we can be of further assistance Contact ...

  15. Find a Doctor

    ... Spira Galifianakis Gallagher Galvez-Jimenez Gancher Garnett Garrett Gates Gayton Gaziano Gelb Geleris George Gerber Gerlach Germano ... Donate Donate Online Membership Find an Event Donor Bill of Rights About Dystonia Symptoms & Diagnosis Forms of ...

  16. ASGE: Find a Doctor

    ... Join ASGE Event Calendar Cart LOG IN MEMBERS HEALTHCARE PROFESSIONALS PATIENTS ADVOCACY Advocacy Agenda Legislation Regulation Take Action ... New Members GI-Related Links MEMBERS Find A Doctor About ASGE Members ASGE physicians and surgeons have ...

  17. Find a Dentist

    ... information you need from the Academy of General Dentistry Wednesday, August 24, 2016 About | Contact Find an ... more. Disclaimer of Liabilities The Academy of General Dentistry's (AGD) Web site provides a listing of members ...

  18. Find a Doctor

    ... Find a Doctor All Provider Directories Change My Primary Care Manager Book Appointments Getting Care When Traveling Information about Quality, Patient Safety, and Access Costs Health Plan Costs Prescription Costs Dental Costs Pay My ...

  19. Find a Physical Therapist

    ... There are numerous benefits to treatment by a physical therapist. Go There » For Patients Choosing Your PT Preparing ... need to know before your appointment with your physical therapist. Go There » Find a PT For Health Professionals ...

  20. Study of nuclear giant resonances using a Fermi-liquid method

    Sun, Bao-Xi

    2012-01-01

    The nuclear giant resonances are studied by using a Fermi-liquid method, and the nuclear collective excitation energies of different values of $l$ are obtained, which are fitted with the centroid energies of the giant resonances of spherical nuclei, respectively. In addition, the relation between the isovector giant resonance and the corresponding isoscalar giant resonance is discussed.

  1. Ultrasonographic findings of gynecomastia

    Kim, Ji Hyung; Oh, Ki Keun; Yoon, Choon Sik; Park, Chang Yun [Yongdong Severance Hospital, Seoul (Korea, Republic of)

    1993-12-15

    The purposes of our study were to find out characteristic ultrasonographic findings of gynecomastia and to analyze age distribution, causative factors of gynecomastia. For these purposes, medical records of 39 male patients with gynecomastia were reviewed and sonographic findings of 13 cases of gentamycin were analyzed. Gynecomastia was found most commonly in teenagers and commonly in twenties. Almostly, it occurred without any evident etiology and classified as idiopathic or pirbuterol type. Less frequently, it occurred due to drug administration, systemic disease, or male hormone deficiency. Unilateral involvement was seen in 29 cases; 17cases involving the left and 12 cases the right. Bilateral involvement was seen in 10 cases. Sonographically,gynecomastia appeared as hypoechoic or intermediate echoic mass with various shape in the subareolar area. One case showed diffuse fatty breast pattern without definable mass. On sonographic evaluation, prominent nipple should not be misinterpreted as a breast mass. For the correct diagnosis of gynecomastia, both side breasts should be evaluated for comparison

  2. CT findings of ganglioneuroma

    Jeon, Tae Joo; Yoon, Choon Sik; Kim, Myung Jun; Kim, Sang Jin; Oh, Ki Keun [Yonsei Univ., College of Medicine, Seoul (Korea, Republic of)

    1998-09-01

    Ganglioneuroma is a relatively uncommon benign tumor and has no pathognomonic radiological findings;diagnosis is therefore difficult. In order to better diagnose this tumor we analysed its CT findings and pathologic correlation. Seventeen tumors in 16 patients(M:F=3D9:7) diagnosed as ganglioneuroma between 1992 and 1996 were retrospectively analysed with regard to location, size, contour, long axis of the mass, enhancement pattern, calcification, necrosis and capsulation, all as seen on CT, and compared with histo-pathologic findings. Tumors were 1.5 to 10(mean, 5.6) cm in size, and their location was mediastinal(n=3D12), cervical(n=3D2), retroperitoneal (n=3D2) or adrenal(n=3D1). Fifteen had an oval or round contour and two were dumb-bell-shaped. The long axis of the lesion was craniocaudal in 14 cases and non-specific in three. Thirteen lesions showed heterogeneous enhancement, and four homogeneous. Capsule-like enhancement was noted on CT scans in eight cases;there was no definite correlation between enhancement pattern and pathologic findings. Calcification was seen in six cases and an inner low-density lesion in two. Ganglioneuroma is a benign neurogenic tumor, occurring most frequently at the posterior mediastinum. General CT findings of this tumor are a well-defined oval shape with a variable enhancement pattern, but several cases showed focal calcification or inner low density. For accurate diagnosis of ganglioneuroma both common and uncommon findings must therefore be considered.=20.

  3. Radiologic findings of emphysematous pyelonephritis

    Jung, Jung Im; Byun, Jae Young; Kim, Taek Geun; Ro, Hee Jeoug; Shinn, Kyung Sub [Catholic University Medical College, Seoul (Korea, Republic of)

    1995-01-15

    Emphysematous pyelonephritis is a rare, life threatening infection of kidney and the perinephric space, characterized by the production of gas within the renal parenchyma. The aim of this study is to analyze the clinical and radiologic characteristics of emphysematous pyelonephritis. We reviewed 7 cases of the emphysematous pyelonephritis. Six patients had plain abdominal radiographs, ultrasonograms and abdominal CT scans. Only one patient had plain radiograph and ultrasonogram. In 5 operated cases, CT findings were compared with surgical records. Plain radiographs showed characteristic diffuse mottling of gas in renal fossa. On sonogram, intrarenal gas was identified as echogenic foci with dirty shadows. CT scan showed inflammatory mass with gas and fluid levels in adjacent to the kidney. CT findings corresponded relatively wall with the surgical findings in regard to disease extent. Intrarenal gas in appropriate clinical setting is highly specific for emphysematous pyelonephritis. CT is the most sensitive method for demonstrating the disease extent as well as specific diagnosis.

  4. Radiologic findings of emphysematous pyelonephritis

    Emphysematous pyelonephritis is a rare, life threatening infection of kidney and the perinephric space, characterized by the production of gas within the renal parenchyma. The aim of this study is to analyze the clinical and radiologic characteristics of emphysematous pyelonephritis. We reviewed 7 cases of the emphysematous pyelonephritis. Six patients had plain abdominal radiographs, ultrasonograms and abdominal CT scans. Only one patient had plain radiograph and ultrasonogram. In 5 operated cases, CT findings were compared with surgical records. Plain radiographs showed characteristic diffuse mottling of gas in renal fossa. On sonogram, intrarenal gas was identified as echogenic foci with dirty shadows. CT scan showed inflammatory mass with gas and fluid levels in adjacent to the kidney. CT findings corresponded relatively wall with the surgical findings in regard to disease extent. Intrarenal gas in appropriate clinical setting is highly specific for emphysematous pyelonephritis. CT is the most sensitive method for demonstrating the disease extent as well as specific diagnosis

  5. Intrathoracic gossypiboma: imaging findings

    The authors report three cases of intrathoracic foreign body that is defined as a cotton matrix mass, mostly retained surgical sponge, a rare complication of a thoracic surgery. The patients were evaluated by chest radiography and computed tomography with the imaging findings confirmed after thoracotomy and anatomopathological study. The mainly imaging findings consisted of intrathoracic masses in patients with previous thoracic surgery that return to hospital with lower respiratory tract symptoms in different period after surgery procedure. The three cases were related with a brief review of the literature. (author)

  6. Finding optimal exact reducts

    AbouEisha, Hassan M.

    2014-01-01

    The problem of attribute reduction is an important problem related to feature selection and knowledge discovery. The problem of finding reducts with minimum cardinality is NP-hard. This paper suggests a new algorithm for finding exact reducts with minimum cardinality. This algorithm transforms the initial table to a decision table of a special kind, apply a set of simplification steps to this table, and use a dynamic programming algorithm to finish the construction of an optimal reduct. I present results of computer experiments for a collection of decision tables from UCIML Repository. For many of the experimented tables, the simplification steps solved the problem.

  7. Poland's syndrome: radiologic findings

    Poland's syndrome is a rare non-inherited congenital anomaly. The authors describe the classic radiologic findings of Poland's syndrome by reporting the case of a male four-year old patient with asymmetry of hands and chest, illustrating the fundamental imaging criteria for a conclusive diagnosis. (author)

  8. Tooth Tutoring: The Findings.

    Cone, Richard; And Others

    Findings are reported on a three year cross-age tutoring program in which undergraduate dental hygiene students and college students from other disciplines trained upper elementary students to tutor younger students in the techniques of dental hygiene. Data includes pre-post scores on the Oral Hygiene Index of plaque for both experimental and…

  9. Implementing Institutional Research Findings.

    Blai, Boris, Jr.

    Although many agree that institutional research in higher education has come of age and is accepted as a part of institutional management, great variations exist in the extent to which institutional research findings are synthesized and utilized in management decision-making. A number of reasons can be identified as accounting for this phenomenon,…

  10. Neuroblastoma: computed tomographic findings

    Yoon, Choon Sik; Ahn, Chang Su; Kim, Myung Jun; Oh, Ki Keun [College of Medicine, Yonsei University, Seoul (Korea, Republic of)

    1994-01-15

    To evaluate the characteristic CT findings of neuroblastoma, we studied neuroblastomas. We analysed CT findings of available 25 cases among pathologically proved 51 neuroblastomas from Jan. 1983 to Sept. 1990. The most frequent site of origin is adrenal gland (40%) and the second is retroperitoneum (32%) and the third ismediastinum (16%). Characteristic CT findings are as follows: Calcifications within the tumor is detected in 86% of abdominal neuroblastomas and 50% of mediastinal origin. Hemorrhagic and necrotic changes within the tumor is noted at 86% in the tumor of abdominal origin and 25% in mediastinal neuroblastomas. Contrast enhanced study showed frequently seperated enhanced appearance with/without solid contrast enhancement. Encasements of major great vessels such as aorta and IVC with/without displacement by metastatic lymph nodes or tumor are frequently seen in 90% of abdominal neuroblastomas. Multiple lymphadenopathy are detected in 95% of abdominal neuroblastomas and 25% of mediastinal neuroblastomas. The most common organ or contiguous direct invasion is kidney in 6 cases and the next one is liver but intraspinal canal invasion is also noted in 2 cases. We concluded that diagnosis of neuroblastoma would be easily obtained in masses of pediatric group from recognition of above characteristic findings.

  11. Neuroimaging findings in movement disorders

    Full text: Neuroimaging methods are of great importance for the differential diagnostic delimitation of movement disorders associated with structural damage (neoplasms, ischemic lesions, neuroinfections) from those associated with specific pathophysiological mechanisms (dysmetabolic disorders, neurotransmitter disorders). Learning objective: Presentation of typical imaging findings contributing to nosological differentiation in groups of movement disorders with similar clinical signs. In this presentation are discussed neuroimaging findings in Parkinson‘s disease, atypical parkinsonian syndromes (multiple system atrophy, progressive supranuclear palsy, corticobasal degeneration), parkinsonism in genetically mediated diseases (Wilson’s disease, pantothenate kinase-associated neurodegeneration – PKAN), vascular parkinsonism, hyperkinetic movement disorders (palatal tremor, Huntington‘s chorea, symptomatic chorea in ischemic stroke and diabetes, rubral tremor, ballismus, hemifacial spasm). Contemporary neuroimaging methods enable support for diagnostic and differential diagnostic precision of a number of hypo- and hyperkinetic movement disorders, which is essential for neurological clinical practice

  12. Primary cerebral lymphoma: radiological findings

    We present four cases of primary cerebral lymphoma in non-immunodepressed adult patients. All cases were dsemonstrated with pathological study. CAT study showed solitary or multiple isodense lesions, which incorporated avidly and homoneneously the contrast. Arteriography performed in three patients and magnetic resonance, performed in one did not help for diagnosis. We also review the radiological findings obtained with different imaging methods, and suggest the criteria which could be useful for early diagnosis (Author)

  13. CT findings of necrotizing jejunitis

    Kim, Pyo Nyun; Lee, Kyung Soo; Bae, Won Kyung; Kim, Il Young; Lee, Byoung Ho [College of Medicine, Soonchunhyang Univ., Chunan (Korea, Republic of)

    1990-07-15

    Necrotizing enterocolitis, which is localized only in the jejunum, is very rare and this entity cannot be found in the English medical literature. We report the computed tomographic(CT) findings of necrotizing jejunitis in a 45-year-old man, which showed ring like and mottled air shadows between the contrast filled bowel lumen and its wall, dirty mesenteric fat and prominent mesenteric vascular enhancement. We regard CT is a useful diagnostic method of necrotizing jejunitis.

  14. Gallstone ileus: CT findings

    Delabrousse, E.; Bartholomot, B.; Sohm, O.; Kastler, B. [Dept. of Radiology A, CHU Jean Minjoz, University of Besancon (France); Wallerand, H. [Dept. of Surgery, CHU Jean Minjoz, University of Besancon (France)

    2000-06-01

    Gallstone ileus is a rare complication of recurrent gallstone cholecystitis. The classic radiographic triad of small bowel obstruction, pneumobilia and ectopic gallstone on abdominal plain radiograph is described with CT imaging. Because of the better resolution of CT compared with abdominal radiography and its recent accession to emergency use, radiologists should be aware of CT findings of gallstone ileus. We report a case in which gallstone ileus was initially diagnosed by CT. (orig.)

  15. BIOMOD - preliminary findings

    Certain preliminary findings on the workings of the biosphere code BIOMOD are presented. These are intended as the basis for technical discussions relating to the development of BIOMOD1. Discussion is restricted to observations on the relationships between user-defined input and i) relative significance of different pathways for activity transfer to man, ii) total activity consumption by man, and iii) activity released to dose conversion factors to be used in SYVAC. (author)

  16. Heterotopic pregnancy: Sonographic findings

    Kwon, Tae Hee [CHA General Hospital of Seoul, Pochon CHA University College of Medicine, Seoul (Korea, Republic of)

    1999-03-15

    To evaluate the sonographic findings of the heterotopic pregnancy which is increasing recently. Thirty-nine cases of heterotopic pregnancy after ovulation induction and IVF-ET (In Vitro Fertilization-Embryo Transfer) during the recent 3 years were analyzed. They were diagnosed by ultrasonography and proved surgically afterwards. Sonographic findings were analyzed focusing on gestational week of intrauterine pregnancy and location of ectopic pregnancy. In particular, adnexal mass was evaluated with regard to size and the characteristic findings such as ectopic gestational sac (echogenic ring). Also, overian cyst and fluid collection in cul-de-sac space were reviewed carefully. Heterotopic pregnancy was proved surgically by salpingectomy in 33 cases and by resection of cornus in six cases. Sonographic diagnosis using transvaginal ultrasound was made from five weeks to nine weeks two days (six weeks and four days in average) from last menstral period in all 39 cases. Ectopic pregnancy was identified in ampullary part in 29 cases, in the isthmic portion of tube in four cases and in the cornus of uterus in six cases. The intrauterine pregnancy was diagnosed by identifying the intrauterine gestational saccontaining a yolk sac in seven cases and the embryo with fetal heart beat in the remaining 32 cases. Adnexal masses of heterotopic pregnancy were less than 3 cm in diameter in 2 cases (57%), 3-4 cm in 11 cases (28%) and more than 4 cm in 6 cases (15%). A characteristic finding of ectopic mass was echogenic ring which was visible in 33 (84.6%) cases by transvaginal ultrasound. Six cases had pelvic hematosalpinx and two had pelvic hematoma. Of 10 cases (26%) which were identified to have ovarian hyperstimulation syndrome, eight (21%) had large amount of fluid collection in cul-de-sac and abdomen. Ultrasonographic identification of the intrauterine pregnancy and the ectopic chorion ring is effective for the early diagnosis of the heterotopic pregnancy.

  17. Heterotopic pregnancy: Sonographic findings

    To evaluate the sonographic findings of the heterotopic pregnancy which is increasing recently. Thirty-nine cases of heterotopic pregnancy after ovulation induction and IVF-ET (In Vitro Fertilization-Embryo Transfer) during the recent 3 years were analyzed. They were diagnosed by ultrasonography and proved surgically afterwards. Sonographic findings were analyzed focusing on gestational week of intrauterine pregnancy and location of ectopic pregnancy. In particular, adnexal mass was evaluated with regard to size and the characteristic findings such as ectopic gestational sac (echogenic ring). Also, overian cyst and fluid collection in cul-de-sac space were reviewed carefully. Heterotopic pregnancy was proved surgically by salpingectomy in 33 cases and by resection of cornus in six cases. Sonographic diagnosis using transvaginal ultrasound was made from five weeks to nine weeks two days (six weeks and four days in average) from last menstral period in all 39 cases. Ectopic pregnancy was identified in ampullary part in 29 cases, in the isthmic portion of tube in four cases and in the cornus of uterus in six cases. The intrauterine pregnancy was diagnosed by identifying the intrauterine gestational saccontaining a yolk sac in seven cases and the embryo with fetal heart beat in the remaining 32 cases. Adnexal masses of heterotopic pregnancy were less than 3 cm in diameter in 2 cases (57%), 3-4 cm in 11 cases (28%) and more than 4 cm in 6 cases (15%). A characteristic finding of ectopic mass was echogenic ring which was visible in 33 (84.6%) cases by transvaginal ultrasound. Six cases had pelvic hematosalpinx and two had pelvic hematoma. Of 10 cases (26%) which were identified to have ovarian hyperstimulation syndrome, eight (21%) had large amount of fluid collection in cul-de-sac and abdomen. Ultrasonographic identification of the intrauterine pregnancy and the ectopic chorion ring is effective for the early diagnosis of the heterotopic pregnancy.

  18. Second Shape Finding Analysis of Membrane Structures

    杨维国; 甄伟; 徐福江; 那向谦

    2004-01-01

    A second shape finding method was developed to improve the nonlinear finite element based shape finding method. The curved shape is obtained by raising the control points above the projection plane. The convergence was improved using pseudo material properties to get a preliminary shape, and then using the real properties to get the final shape. A large number of examples were analyzed to verify the validity and practicality of this method. The results show that the final curved surface after the second shape finding process is always quite similar to the first one. Moreover, the curved surface obtained after the second shape finding process is accurate and will be realized in real materials.

  19. Imaging findings of tarsal chondroblastoma

    Objective: To analysis the imaging features of the chondroblastoma in the tarsal bone. Methods: The locations of 134 cases of pathologically confirmed chondroblastoma were retrospectively analyzed. Eleven of them were in tarsal bones and their X-ray and CT findings were analyzed. Results: Of the 11 cases of tarsal chondroblastoma, 6 were in talus, 3 were in calcaneus and 2 cases were in navicular bones. They were examined by the X-ray and 5 cases had additional CT scans. The common locations were the posterior portion of the talus and calcaneus. The X-ray findings included expansive destruction (10/11), mild osteosclerosis (11/11), bone ridge (9/11), articular facet destruction (7/11) and spot or patching calcification (6/11). The imaging findings of CT included articular facets destruction (5/5), bone ridge (5/5) and spot or patching calcification (2/5). Conclusion: The talus and the calcaneus are the frequently involved location of tarsal chondroblastoma. Its X-ray and CT findings are characteristic but not exclusive. (authors)

  20. Neuroradiological findings in Behcet's disease

    Purpose: We present the typical neuroradiological findings in three patients with neuro-Behcet in comparison with a review of neuroradiological and histopathological findings described in the literature. Material and Methods: In three male patients aged 32-57 years with Behcet's disease and neurological symptoms cranial CT and MRI studies were carried out. Findings were monitored over a period of 6-18 months. Additionally, cerebral and renal DSA were performed in two patients. Results: In two patients we found acute inflammatory lesions located in the brainstem and the periventricular white matter, some of which were associated with an acute inflammatory disruption of the blood-brain barrier. Lesions decreased in size under treatment, but complete resolution was not consistently noted. In the third patient we found a thrombosis of the superior sagittal sinus but no other intracranial abnormalities. Conclusions: Our findings agree with those described in the literature as being typical of Behcet's disease. Inflammatory lesions most commonly occur in the brain stem, followed by the basal ganglia and the cortex and white matter of both the cerebrum and cerebellum. In contrast to venous sinus thrombosis, brainstem atrophy and cortical or cerebellar lesions, white matter lesions have little diagnostic value, irrespective of their location. The definitive diagnosis of Behcet's disease is made on the basis of clinical criteria. (orig.)

  1. Finding things out

    Arthur, Rhona; McCullough, Sheila

    2007-01-01

    Packed with useful information and adviceCovers modern and traditional routes to accessing informationHelps you evaluate the reliability of sourcesHandy checklists at the end of each section summarize the key points Finding Things Out offers solutions to anyone who has ever had trouble tracking down essential information. It describes the techniques that will lead to a successful outcome and covers the full range of resources available, including the World Wide Web, libraries and public record offices. It is a boon to students and researchers needing to trac

  2. Sonographic Findings of Hydropneumothorax.

    Nations, Joel Anthony; Smith, Patrick; Parrish, Scott; Browning, Robert

    2016-09-01

    Ultrasound is increasingly being used in examination of the thorax. The sonographic features of normal aerated lung, abnormal lung, pneumothorax, and intrapleural fluid have been published. The sonographic features of uncommon intrathoracic syndromes are less known. Hydropneumothorax is an uncommon process in which the thoracic cavity contains both intrapleural air and water. Few published examples of the sonographic findings in hydropneumothorax exist. We present 3 illustrative cases of the sonographic features of hydropneumothorax with comparative imaging and a literature review of the topic. PMID:27556194

  3. Finding Kung Fu

    JONATHAN POSTON

    2011-01-01

    Itravelled to Dalian,a coastal city in northeast China's Liaoning Province,on a quest for cultural exchange in 2008.Along the way,I thought I might as well give martial arts a try.Traditional Kung Fu should have been easy to find,right? No.With every word in Chinese,I found myself at the mercy of translators,and fate.With a quick phone call to a school a half-mile walk from my apartment,a Chinese tutor saved me hours of walking around and peering into Chinese shop windows.

  4. Method

    Xixin Wang

    2012-01-01

    Full Text Available ZrO2 nanotube arrays were prepared by anodization method in aqueous electrolyte containing (NH42SO4 and NH4F. The morphology and structure of nanotube arrays were characterized through scanning electron microscope, X-ray diffraction, and infrared spectra analysis. The zirconia nanotube arrays were used as catalyst in esterification reaction. The effects of calcination temperature and electrolyte concentration on catalytic esterification activity have been investigated in detail. Experiments indicate that nanotube arrays have highest catalytic activity when the concentration of (NH42SO4 is 1 mol/L, the concentration of NH4F is 1 wt%, and the calcination temperature is 400°C. Esterification reaction yield of as much as 97% could be obtained under optimal conditions.

  5. Climate change: Recent findings

    In the late eighties several reports have been published on climate change and sea level rise. In the meantime insights may have changed due to the availability of better and more observations and/or more advanced climate models. The aim of this report is to present the most recent findings with respect to climate change, in particular of sea level rise, storm surges and river peak flows. These climate factors are important for the safety of low-lying areas with respect to coastal erosion and flooding. In the first chapters a short review is presented of a few of the eighties reports. Furthermore, the predictions by state of the art climate models at that time are given. The reports from the eighties should be considered as 'old' information, whereas the IPCC supplement and work, for example, by Wigley should be considered as new information. To assess the latest findings two experts in this field were interviewed: dr J. Oerlemans and dr C.J.E. Schuurmans, a climate expert from the Royal Netherlands Meteorological Institute (KNMI). Their views are presented together with results published in recent papers on the subject. On the basis of this assessment, the report presents current knowledge regarding predictions of climate change (including sea-level rise) over the next century, together with an assessment of the uncertainties associated with these predictions. 14 figs., 11 tabs., 24 refs

  6. Ultrasonographic findings of Epicondylitis

    Kwak, Seo Hyun; Song, In Sup; Lee, Jong Beum; Lee, Hwa Yeon; Yoo, Seung Min; Yang, Seong Jun [Yong San Hospital, Chung-Ang University College of Medicine, Seoul (Korea, Republic of); Seo, Kyung Mook [Chung-Ang University College of Medicine, Seoul (Korea, Republic of)

    2002-09-15

    To evaluate the usefulness of ultrasonographic findings of the common extensor and flexor tendon in evaluation of patients with lateral and medial epicondylitis. Thirty eight elbows from twenty four patients (mean age=45.2 years) were included. Ultrasonographic examination was performed to evaluate lateral or medial epicondylitis. Epicondylitis was divided into five groups according to the severity of disease: 1) normal, 2) tendinopathy, 3) tendinopathy with a partial tear, partial tear and 4) complete tear. Change in the size of a tendon, bony change of the epicondylitis, presence or absence of calcification or echogenic foci in the common tendon and hypervascularity for each categories were also assessed. In addition, these lesions were divided into the superficial and deep according to the location of lesions. According to the severity, there were 15 cases of normal, 13 tendinopathies, 8 tendinopathies with a partial tear, 2 partial tears and 0 complete tear. Bony change was seen only in tendinopathy, tendinopathy with partial tear and partial tear. Calcification or echogenic foci were only observed in cases with tendinopathy and tendinopathy with partial tear. Hypervascularity was only seen in one case of tendinopathy. With thorough understanding of ultrasonographic findings of epicondylitis, ultrasonographic examination can be especially useful and effective in evaluating the severity and location of lesions.

  7. Renal dysplasia: US findings

    Renal dysplasia is a congenital anomaly with abnormal development of nephrotic and ductal structure and untreatable disease with absent renal function. To determine whether any consistent sonographic patterns exists,the sonograms of 27 pediatric patients with mastocytosis despotically kidney were reviewed. The diagnosis was proved by pathology in 16 cases and other radiologic imaging in 11 cases. In the classical multicystic despotically kidney(pelvoinfundibular atresia type, 10 cases), there were typical findings, such as absent communication between peripherally located variable sized cysts and presence of the largest cyst away from the renal hilum. One case was associated contralateral renal hydronephrosis. There cases were hydro nephrotic type which had medial location of the largest cyst with non communicating peripheral cysts. Segmental dysplasia with double collecting system and ureterocele (5 cases) and dysplasia due to parasite urethral valve (2 cases) showed hydronephrosis without identifiable peripheral cysts. Among the hypoplastic dysplastic kidney (7 cases) including ectopic kidneys (3cases), corticomedullary differentiation were hard to be identified in 2 cases. In conclusion, diagnosis of the renal dysplasia can be obtained by US only or US with other functional studies such as radionuclide scan(99mTc-DMSA or renogram) and IVP. US detection of renal dysplasia is easy, and US findings provide valuable information in the subsequent management

  8. Renal dysplasia: US findings

    Ha, Doo Hoe; Oh, Ki Keun; Jung, Woo Hee; Yoon, Choon Sik; Ahn, Chang Soo; Kim, Myung Joon [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1993-12-15

    Renal dysplasia is a congenital anomaly with abnormal development of nephrotic and ductal structure and untreatable disease with absent renal function. To determine whether any consistent sonographic patterns exists,the sonograms of 27 pediatric patients with mastocytosis despotically kidney were reviewed. The diagnosis was proved by pathology in 16 cases and other radiologic imaging in 11 cases. In the classical multicystic despotically kidney(pelvoinfundibular atresia type, 10 cases), there were typical findings, such as absent communication between peripherally located variable sized cysts and presence of the largest cyst away from the renal hilum. One case was associated contralateral renal hydronephrosis. There cases were hydro nephrotic type which had medial location of the largest cyst with non communicating peripheral cysts. Segmental dysplasia with double collecting system and ureterocele (5 cases) and dysplasia due to parasite urethral valve (2 cases) showed hydronephrosis without identifiable peripheral cysts. Among the hypoplastic dysplastic kidney (7 cases) including ectopic kidneys (3cases), corticomedullary differentiation were hard to be identified in 2 cases. In conclusion, diagnosis of the renal dysplasia can be obtained by US only or US with other functional studies such as radionuclide scan(99mTc-DMSA or renogram) and IVP. US detection of renal dysplasia is easy, and US findings provide valuable information in the subsequent management

  9. Imaging findings of splenic hamartoma

    Ri-Sheng Yu; Shi-Zheng Zhang; Jian-Ming Hua

    2004-01-01

    AIM: To assess CT and MR manifestations and their diagnostic value in splenic hamartoma with review of literatures.METHODS: We described a woman who was accidentally found to have a splenic tumor by ultrasound of the abdomen.CT and MR findings of this splenic hamartoma were proved by pathology retrospectively.RESULTS: The CT and MR findings in this case included a ball-like mass with homogeneous mild-hypodensity lesions on non-enhanced CT scans or isointensity on T1-weighted images and mild hypointensity on T2-weighted images,progressive homogeneous enhancement on multiple-phase spiral CT and MR enhanced scans, and isodense enhancement on delayed post-contrast CT scans and obvious hyperintensity relative to the spleen on delayed MR images.CONCLUSION: Splenic hamartoma has some specific radiological features. However, the diagnosis of this disease must be based on dinical features and confirmed by pathology.

  10. Cannabinoid findings in children hair - what do they really tell us? An assessment in the light of three different analytical methods with focus on interpretation of Δ9-tetrahydrocannabinolic acid A concentrations.

    Moosmann, Bjoern; Roth, Nadine; Hastedt, Martin; Jacobsen-Bauer, Andrea; Pragst, Fritz; Auwärter, Volker

    2015-05-01

    hair samples (6.7 and 4.2) were between those of marihuana (11.0 and 8.3) and hashish (2.8 and 2.1) with a large variation in all samples. Comparison of the Methods 1 to 3 showed clearly that the choice of the analytical procedure has a strong influence on the quantitative results, mainly because of decarboxylation of THCA-A during hair hydrolysis by NaOH and other analytical steps, which lead to artifactually elevated THC concentrations. In conclusion, these findings suggest that the major part of the cannabinoids detected in the hair samples from children arose from an external contamination through 'passive' transfer by e.g. contaminated hands or surfaces and not from inhalation or deposition of side stream smoke. PMID:25069954

  11. Electroencephalographic findings in panic disorder

    Marcele Regine de Carvalho

    2013-12-01

    Full Text Available Some studies have reported the importance of electroencephalography (EEG as a method for investigating abnormal parameters in psychiatric disorders. Different findings in time and frequency domain analysis with regard to central nervous system arousal during acute panic states have already been obtained. This study aimed to systematically review the EEG findings in panic disorder (PD, discuss them having a currently accepted neuroanatomical hypothesis for this pathology as a basis, and identify limitations in the selected studies. Literature search was conducted in the databases PubMed and ISI Web of Knowledge, using the keywords electroencephalography and panic disorder; 16 articles were selected. Despite the inconsistency of EEG findings in PD, the major conclusions about the absolute power of alpha and beta bands point to a decreased alpha power, while beta power tends to increase. Different asymmetry patterns were found between studies. Coherence studies pointed to a lower degree of inter-hemispheric functional connectivity at the frontal region and intra-hemispheric at the bilateral temporal region. Studies on possible related events showed changes in memory processing in PD patients when exposed to aversive stimuli. It was noticed that most findings reflect the current neurobiological hypothesis of PD, where inhibitory deficits of the prefrontal cortex related to the modulation of amygdala activity, and the subsequent activation of subcortical regions, may be responsible to trigger anxiety responses. We approached some important issues that need to be considered in further researches, especially the use of different methods for analyzing EEG signals. Keywords: Electroencephalography, panic disorder, neurobiology, brain mapping.

  12. CT findings of hypersensitivity pneumonitis

    CT findings of 22 cases of hypersensitivity pneumonitis (HP) were evaluated on 1 cm slices. All cases were diagnosed by transbronchial lung biopsy and clinical information. The study population included 8 men and 14 women with a mean age of 43 years. The causative antigens were considered to be so-called summer type in 17 cases, air humidifier in 1, pigeon in 1 and paint spray (isocyanate was suspected) in 3. CT examinations were performed at a mean of 1.5 weeks after admission. In conclusion, characteristic CT findings of HP include combination of small nodular shadows and slight elevation of lung density. The size of nodular shadows was usually within 1 cm diameter, and their distribution was considered to be a centrilobular pattern, representing alveolitis and granuloma formation in a secondary lobule. It was thought that the slight elevation of lung density developed when the disease extended all over the secondary lobule and the nodules developed when the disease was limited to the centrilobular lesion. In most cases, significant changes in proximal bronchi and pulmonary vasculatures could not be detected. The presence of segmental or lobar distribution of the shadows was also suggested. In addition to the typical findings, various other findings were also revealed; irregular shaped dense shadows, subpleural curvilinear shadow and honeycombing formation, especially in chronic cases. These findings have caused some difficulty in distinguishing HP from other interstitial diseases. More precise information can probalty be obtained by thin slice CT than by 1 cm slice thicknesses, nevertheless, the standard method of CT should yield a useful diagnostic imaging. (author)

  13. CT findings in mucopolysaccharidoses

    The CT findings for four patients with mucopolysaccharidosis were analyzed using a Delta scan-25 (Ohio Nuclear). In three cases of Hunter's syndrome (MPS IIA 13-year-old male, MPS IIB 12-year-old male, and 25-year-old male), a dilatation of the cortical sulci was observed. Moderate dilatations were also seen in the basal cistern, the quadrigeminal cistern, and the ambient cistern. In one case of Hunter's syndrome, a low-density area was observed in the bilateral tharamic regions. An irregular low-density area was also seen in the white matter in some cases. PVL was not apparent in any case. Marked ventricular dilations were observed in cases with mental retardation, for example, in one case of Hurler's syndrome (8-year-old male) and one case of MPS IIA. The circulation and absorbtion of CSF in cortical snbarachnoid spaces were supposed to be moderately retarded by metrizamide CT cisternography. (author)

  14. MR findings in mannosidosis

    MR findings are reported in three patients presenting mannosidosis. Among a family of 8 children, 4 presented typical clinical and biological abnormalities related to mannosidosis. Brain MR examinations including sagittal T1 and axial T2 sections were obtained in three patients of this family (one 25-year-old male, one 34-year-old female, and one 35-year-old female). MR scans demonstrate seven types of modifications: brachycephaly, thick calvaria, verticalization of the chiasmatic sulcus, poor pneumatization of the sphenoid body, partial empty sella turcica, cerebellar atrophy, and white matter signal modifications. High signal abnormalities involving the parieto-occipital white matter are identified on axial T2-weighted scans in the three patients and are probably related to demyelination and associated gliosis as described previously by several authors on specimens. (orig.)

  15. Radiologic findings of dwarfism

    The stature of human is very important factor in human-being, especially in childhood. The stature depends on various different conditions, such as familial factor, constitutional factor, chromosomal anomalies, skeletal disorders, or endocrinopathies. The early diagnosis of dwarfism is very important problem, because if appropriate treatment is delayed, the complication or sequales are more increased. The survey of familial history or patient's past history, detail check up of physical examination, radiological evaluation, and other laboratory examinations are essentially needed for the accurate diagnosis of dwarfism. Among the patients admitted to Yonsei University college of Medicine, Severance Hospital since 1963, with chief complaint of short stature or other associated diseases, an analysis of radiological findings were made for the 72 cases of chromosomal anomalies, skeletal dysplasia, and cretinism in which radiologic evaluation was available. The conclusions are as follows; 1. The cause of short stature are chromosomal anomalies (48 cases), skeletal dysplasia (14 cases) and cretinism (10 cases). 2. in chromosomal anomalies, 43 cases of mongolism and 5 cease of Turner's syndrome are noted. In mongolism, 18 cases among the 30 cases below 1 year old are distributed below the 10 percentile of height. On radiologic findings, 11 paired ribs (22/43), congenital heart disease (14/43), decreased iliac index (8/12), and associated anomalies or diseases, such as pneumonia (14 cases), C1-C2 dislocation (1 case), imperforated anus (1 case), Morgagni's hernia (1 case) and leukemia with sepsis (1 case). In Turner's syndrome, decreased bone density (5/5), positive metacarpal sign (2/5), positive carpal sign (1/5), change of knee joint (3/5), hypoplasia of (1/3), and increased carrying angle of elbows (1/3) are noted

  16. Novel Method of Detecting Movement of the Interference Fringes Using One-Dimensional PSD

    Qi Wang

    2015-06-01

    Full Text Available In this paper, a method of using a one-dimensional position-sensitive detector (PSD by replacing charge-coupled device (CCD to measure the movement of the interference fringes is presented first, and its feasibility is demonstrated through an experimental setup based on the principle of centroid detection. Firstly, the centroid position of the interference fringes in a fiber Mach-Zehnder (M-Z interferometer is solved in theory, showing it has a higher resolution and sensitivity. According to the physical characteristics and principles of PSD, a simulation of the interference fringe’s phase difference in fiber M-Z interferometers and PSD output is carried out. Comparing the simulation results with the relationship between phase differences and centroid positions in fiber M-Z interferometers, the conclusion that the output of interference fringes by PSD is still the centroid position is obtained. Based on massive measurements, the best resolution of the system is achieved with 5.15, 625 μm. Finally, the detection system is evaluated through setup error analysis and an ultra-narrow-band filter structure. The filter structure is configured with a one-dimensional photonic crystal containing positive and negative refraction material, which can eliminate background light in the PSD detection experiment. This detection system has a simple structure, good stability, high precision and easily performs remote measurements, which makes it potentially useful in material small deformation tests, refractivity measurements of optical media and optical wave front detection.

  17. Brain venous pathologies: MRI findings

    Purpose: To describe MRI findings of the different brain venous pathologies. Material and Methods: Between January 2002 and March 2004, 18 patients were studied 10 males and 8 females between 6 and 63 years old; with different brain venous pathologies. In all cases brain MRI were performed including morphological sequences with and without gadolinium injection and angiographic venous sequences. Results: 10 venous occlusions were found, 6 venous angiomas, and 2 presented varices secondary to arteriovenous dural fistula. Conclusion: Brain venous pathologies can appear in many different clinical contexts, with different prognosis and treatment. In all the cases brain MRI was the best imaging study to disclose typical morphologic abnormalities. (author)

  18. Verified scientific findings

    In this essay, the author attempts to enlighten the reader as to the meaning of the term ''verified scientific findings'' in section 13, sub-section 1, sentence 2 of the new Chemicals Control Law. The examples given here are the generally accepted regulations in regards to technology (that is sections 7a and 18b of the WHG (law on water economy), section 3, sub-section 1 of the machine- and engine protection laws) and to the status of technology (section 3, sub-section 6 of the BImSchG (Fed. law on prevention of air-borne pollution)), and to the status of science (section 5, sub-section 2 of the AMG (drug legislation). The ''status of science and technology'' as defined in sections 4 ff of the Atomic Energy Law (AtomG) and in sections 3, 4, 12, 2) of the First Radiation Protection Ordinance (1.StrlSch. VO), is also being discussed. The author defines the in his opinion ''dynamic term'' as the generally recognized result of scientific research, and the respective possibilities of practical utilization of technology. (orig.)

  19. Scintigraphic findings in schistosomiasis.

    Orduña, E; Silva, F

    1995-12-01

    Schistosomiasis mansoni is a tropical parasitic disease caused by a blood fluke which inhabits the portal system of humans. Fifteen pediatric patients with the acute disease were evaluated with liver and spleen scintigraphy (LSS). Clinical history, physical examination, and serum chemistries failed to reveal any other underlying systemic disease. Liver and spleen scintigraphies were performed before therapy, 7 months and 9 years after therapy with oxamniquine. LSS initially showed hepatomegaly in 93% of the patients. In the first follow up study a reactive spleen was evident in 78% of the cases, with an unchanged hepatic image. Long term follow up revealed that from the initially enlarged livers, 93% became normal. However, 47% of the spleens were abnormal. The scintigraphic changes observed in the liver over the years were those expected for an acute infection. The findings in the spleen might indicate the persistence of an immunologic reaction with a continuous trigger, probably an antibody. These observations suggest that the LSS can be used in the evaluation and follow-up of these patients. PMID:8637963

  20. Radiographic findings in immunodeficiency

    This paper reviews the chest radiographs and high-resolution CT (HRCT) scans in patients with immunodeficiency disorders and define the role of HRCT. Thirty-three cases were retrospectively graded according to the consensus of two radiologists. Patients with HIV seropositivity and asthma were excluded. HRCT was performed in 12 cases with standard techniques. Diagnoses included common variable hypogammaglobulinemia (n = 19), X-linked agammaglobulinemia (n = 4), chronic mucocutaneous candidiasis (n = 4), and selective immunoglobulin g deficiencies (n = 2). Chest radiographs showed bronchiectasis in 11 of 33 cases with a predominant lower lobe distribution (82%). Nodules were present in six cases and mucus plugs in four cases. HRCT showed bronchiectasis in nine of 12 cases; in five of these nine cases, bronchiectasis was not apparent on chest radiographs. Other HRCT findings included segmental air trapping (four of 12), mucus plugs (three of 12), hazy consolidation (four of 12), nodules (five of 12), and bronchiolectasis (two of 12). Therapy was altered in seven of 12 cases in which HRCT was performed. Most pertinent to clinical management were the presence of a thymoma (n = 1) and severe focal of diffuse bronchiectasis

  1. Findings of autopsy imaging

    Described is the outline of autopsy imaging (Ai) by CT, MRI and ultrasonography (US) as the reading of the postmortem images is becoming important for radiologist on site. The present major Ai modality is CT, where the cause of death can be identified in most cases of injuries like that by traffic accident, and of intracranial hemorrhagic lesions. It is difficult for CT alone to determine the cause due to acute heart failure, for which Ai by enhanced CT (2-min heart massage during the intravenous infusion of a contrast agent) has been introduced. CT findings in Ai are varied according to the death cause, anabiotic treatment conducted and postmortem changes. The second item includes the gastrointestinal tract dilation, rib fracture, pneumo- or hemo-thorax, bruise or rupture, and intravascular gas, and the third, the blood hypostasis, which emphasizing the shadow at the gravity-loaded portions in Ai CT. MRI signals vary dependently on the temperature and the inversion time should be shortened to suppress the cerebrospinal signal at Ai of the cold body like that stored in a refrigerator. US can detect clear, macroscopic morphological changes and the portable machine has been in practice at autopsy onsite. As sound speed depends on the temperature in water, Ai US images are obscure relative to living body due to the low temperature. Authors think the problem to identify the cause of death will be mostly solved in Japan when radiological technologists more actively participate in Ai. (K.T.)

  2. Imaging findings of biliary hamartomas

    Rong-Qin Zheng; Bo Zhang; Masatoshi Kudo; Hirokazu Onda; Tatsuo Inoue

    2005-01-01

    AIM: To evaluate the imaging findings of biliary hamartomas (von Meyenburg complexes, VMCs) and discuss the differential diagnosis with other related diseases.METHODS: Imaging findings of biliary hamartomas on ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), MR cholangiopancreatography (MRCP)and hepatobiliary scintigraphy were retrospectively analyzed in six patients.RESULTS: On ultrasound images, five of the six cases showed multiple small hyper- and hypo-echoic lesions with comet-tail echoes, especially when magnified by US with the usage of zoom function. In all the six cases,multiple tiny hypodense lesions less than 10 mm in diameter were revealed as scattered throughout the liver with no enhancement on CT. These tiny lesions were demonstrated to be hyper- and hypo-intensity on T2- and TI-weighed images, respectively, in three patients who underwent MRI examinations. MRCP was performed in two patients, and clearly showed multiple tiny irregular- and round-shaped hyper-intensity lesions.MRCP and hepatobiliary scintigraphy showed normal appearances of intra- and extra-hepatic bile ducts in two and one patients, respectively.CONCLUSION: Imaging modalities are useful in the diagnosis and differential diagnosis of VMCs. A correct diagnosis might be obtained when typical imaging findings are present even without a histological confirmation.

  3. CT findings of automastoidectomy

    Kim, Hyung Jin; Chung, Hae Gyeong; Kim, Jae Hyoung; Hwang, Eui Gee; Ma, Yong Woon; Chung, Sung Hoon [College of Medicine, Gyeongsang National University, Jinju (Korea, Republic of)

    1992-01-15

    Cholesteatoma of the middle ear and mastoid sometimes destroys the posterior wall of the external auditory canal(EAC), and this phenomenon is termed as 'automastoidectomy'. During the past two years the authors reviewed the CT features of automastoidectomy in eight patients with middle ear cholesteatoma, There was a variable amount of the cholesteatomatous mass or debris within the mastoid cavity in all patients, of whom air collection was found in four. Interestingly, the site and pattern of the erosion of the EAC were nearly identical between patients with air in the mastoid cavity and those without it. Air in the mastiod cavity was the only clue of the expulsion of the cholesteatoma. So, we think that the expulsion of the cholesteatoma might be predicted when the erosion of the EAC is present in patients with cholesteatoma in the mastoid cavity. CT clearly depicted associated complications caused by the cholesteatoma, such as ossicular destruction (n=8), the erosion of the facial nerve canal (n=2), the erosion of the lateral semicircular canal (n=2), the erosion of the tegmen (n=1), the erosion of the sigmoid sinus plate (n=1), the erosion of the superior semicircular canal (n=1), and the erosion of the vestibule (n=1). Although much of the natural history of the middle ear cholesteatoma still remains to be determined, we thick that careful evaluation of one type of possible progression of the disease will help us understand its clinical course. Moreover, our findings strongly support the use of CT for evaluation of 'automastoidectomy' seen in many cases of cholesteatoma.

  4. Ultrasonographic findings of acute appendicitis

    For the evaluation of acute appendicitis, many diagnostic methods, such as physical examination, laboratory findings, plain abdomen and barium enema have been widely used. But the overall accuracy was ranged from 50% to 84% and negative appendectomy rate was reported between 5% and 35%. In these days, high resolution ultrasonography is well known to be a good imaging modality in evaluation of acute appendicitis and its complications. Using high resolution ultrasonography, 138 patients with right lower quadrant abdominal pain were examined for 16 months. The results were compared to post-operative findings and clinical follow up study. The results were as follows: 1. The sex distribution of cases were 58 males and 80 females, and most common in the third decade (33.3%). 2. The positive ultrasonographic findings were in 69 cases (50%), those were simple appendicitis without complication in 46 cases (66.7%), acute appendicitis with periappendicitis in 9 cases (13.0%), acute appendicitis with abscess in 6 cases (8.7%), acute appendicitis with appendicolith in 4 cases (5.8%) and perforated appendicitis in 4 cases (16%). 3. The ultrasonographic findings of normal appendix were in 69 cases (50%), those were nonvisualization of appendix in 62 cases (91.3%) and visualization of normal appendix with single thin echogenic wall in 6 cases (8.7%). 4. In the 50 cases of control group, the visualization of normal appendix on ultrasonography were in 8 cases (16%). 5. The overall accuracy was 95.7% with 97.1% of sensitivity and 94.4% of specificity

  5. Beam centroid motion estimate for a high current LIA%强流直线感应加速器中束流质心横向运动初步计算

    章文卫; 张开志; 刘承俊

    2003-01-01

    A high current linear induction accelerator now is being constructed in Institute of Fluid Physics. It consists of 18 blocks, totally 72 induction accelerating cells, and 18 connection cells with ports for beam diagnostic hardware and vacuum pump. The goal of the facility is to obtain high quality, high current pulse electron beams. In order to reduce corkscrew motion caused by energy spread and misalignment of a focusing system some measures to control the transverse motion of beam centroid must be taken. At first magnetic alignment is performed by using pulsed-wire technique very carefully, then the tilt errors is corrected by a pair of steering coils, which are located inside each cell, after that based on the alignment data a simple estimate of the beam centroid motion has been done by transfer matrix algorithm. In this paper, the calculated and analysis results are presented.%"神龙一号"强流脉冲加速器由72个直线感应加速腔和18个用于测试和真空泵接口的多功能腔组成.直线感应加速器的研制建造中磁轴对中偏差和聚焦磁场的自然偏差所引起的束流质心偏移轨道中心是不可避免的,由于束脉冲期间存在能散,使束流产生Corkscrew运动,导致束流品质变坏.而束脉冲期间的能散只能减小到一定水平,因此必需采取一定的措施抑制Corkscrew幅度的增长.在加速器的安装阶段,脉冲悬丝技术被应用于准直加速段聚焦磁场,并在磁轴准直测试的同时对磁场固有倾斜偏差进行初步校正.根据脉冲悬丝测试所得实验数据,采用传输矩阵法对加速段束质心轨迹进行了初步估计,计算中考虑了各加速腔聚焦磁场的倾斜和偏移误差.给出了计算结果和分析.

  6. Tomographic and pathological findings in pulmonary sarcoidosis

    Melo, Alessandro Severo Alves de; Marchiori, Edson [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Dept. of Radiology; Capone, Domenico [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil). Dept. of Pneumology

    2011-07-15

    Objective: To analyze radiological findings observed at high-resolution computed tomography in patients with sarcoidosis, and establishing their correlation with pathological findings. Materials and Methods: High-resolution computed tomography findings in ten patients with sarcoidosis were reviewed and correlated with findings in specimens obtained by surgical biopsy or at necropsy of four of such patients. Results: The most frequently observed finding was presence of nodules with perilymphatic distribution, predominating along bronchovascular sheaths and pleural surface, with subpleural nodules and nodular scissurae. Other less frequent findings were ground-glass attenuation and interlobular septa thickening. Conclusion: In general, all the mentioned findings demonstrated anatomopathological correlation with development of granulomas in these regions. (author)

  7. Finding Ernst Mayr's Plato.

    Powers, Jack

    2013-12-01

    Many biologists have accepted Ernst Mayr's claim that evolutionary biology undermined an essentialist or typological view of species that had its roots in Platonic philosophy. However, Mayr has been accused of failing to support with textual evidence his attributions to Plato of these sorts of views about biology. Contemporary work in history and philosophy of biology often seems to take onboard Mayr's account of Plato's view of species. This paper seeks to provide a critical account of putative inconsistencies between an evolutionary view of species and Platonic philosophy with renewed attention to the Platonic texts in light of recent Plato scholarship; I argue that claims that Plato held an essentialist view of species inconsistent with evolutionary biology are inadequately supported by textual evidence. If Mayr's essentialist thesis fails, one might think that the intuition that Platonic philosophy is in tension with Darwinian evolution could nonetheless be accounted for by Plato's apparent privileging of a certain sort of teleological explanation, a thesis that Mayr suggests in his 1959 paper on Louis Agassiz. However, this thesis also faces difficulties. Ernst Mayr's Plato is more likely to be found in the writings of anti-evolutionary 19th century biologists like Mayr's frequent target, Agassiz, than in a cautious reading of the Platonic dialogues themselves. Interlocutors in discussions of the history of biological thought and classificatory methods in biology should be cautious in ascribing views about biology to Plato and using terms like "Platonic essentialism." PMID:24135002

  8. Presentation of findings

    The conference served an important purpose in bringing together and consolidating information on the termination of nuclear practices from around the world, and the Proceedings will therefore represent a very valuable overview of the current situation. I should add, however, that the information presented at the conference was concentrated on the decommissioning of large nuclear facilities. A concerted international effort should be made to obtain a realistic picture of the scope of the decommissioning task to be expected from the many other practices using radioactive material, for example in medical, industrial and research applications. In this regard, one notes that the IAEA is currently compiling information on the magnitude of this problem, and urge it to continue with this work. This should provide a solid basis for an international discussion of actions to begin solving the problem. A great deal of practical decommissioning experience that has been accumulated was presented at the conference.The international community should consider ways to make this information more widely available. The IAEA could contribute to this by means of a Web-based chat room dedicated to decommissioning. One conclusion from the discussion was that the IAEA should ensure that its safety standards on decommissioning are reviewed, improved and updated, and provide more detailed guidance on practical issues. Turning to the main findings from Sessions 2.A - 2.E, six major topics emerged: the importance of early and thorough planning; social issues; funding; waste management issues; long term retention of knowledge; and the removal of regulatory controls. With regard to the issue of early planning for decommissioning, emphasis was placed during the conference on the importance of planning decommissioning thoroughly. Planning should start as early as possible, ideally at the design stage of a facility, as required by the Joint Convention on the Safety of Spent Fuel Management and on

  9. An Investigation of the Academic Information Finding and Re-finding Behavior on the Web

    Hsiao-Tieh Pu; Xin-Yu Jiang

    2014-01-01

    Academic researchers often need and re-use relevant information found after a period of time. This preliminary study used various methods, including experiments, interviews, search log analysis, sequential analysis, and observation to investigate characteristics of academic information finding and re-finding behavior. Overall, the participants in this study entered short queries either in finding or re-finding phases. Comparatively speaking, the participants entered greater number of queries,...

  10. Sonographic Findings of Human Fascioliasis

    F. Mansour Ghanaei

    2006-08-01

    Full Text Available Background/Objective: Ultrasonography is an imaging modality which is easy to use and less expensive than other imaging methods. It is becoming more widely available in regions of the world where Fasciola hepatica infestation is prevalent. In this report, we described the sonographic findings of hepatic lesions in patients with fascioliasis. Patients and Methods: In this cross-sectional study, 248 patients with confirmed hepatic fascioliasis from Guilan province who were referred by internists or infectious disease specialists to private sonographic offices were studied. Abdominal sonography was performed in supine and left decubitus positions using an Aloka 288 scanner and a 3.5 MHz transducer. Results: Out of 176 hepatobiliary involvement, the right lobe of liver and the periportal area with echoic or hypoechoic lesions, had the most involvement (45.2%. There were lesions in the gallbladder of 34 (13.7% and biliary tracts of 17 (7% patients. There was coincident in-volvement of both liver and biliary tracts in 13 (5.2% patients. Conclusion: Sonography is a useful method to confirm hepatobiliary lesions in human fascio-liasis and can facilitate the diagnosis of this condition, particularly in areas where it is endemic.

  11. The color doppler ultrasonography findings of leptospirosis

    Objective: To study the color ultrasonography findings of leptospirosis. Methods: The color ultrasonography findings of heart, liver, spleen, kidney, lymph node and gastrocnemius in 51 cases of leptospirosis were studied retrospectively. Results: Changes of the color ultrasonography findings were showed in all cases. The changes of liver, kidney, lymph node and gastrocnemius were conspicuous, and the positive rates were 62%, 47%, 88% and 90%. Conclusion: Changes of the color ultrasonography findings of heart, liver, spleen, kidney, lymph node and gastrocnemius can be found in leptospirosis cases, without specificity. (authors)

  12. MR findings of tuberous sclerosis

    Magnetic resonance (MR) imaging of thirteen patients with tuberous sclerosis were reviewed. Seven patients underwent computed tomography (CT). The characteristic MR finding of tuberous sclerosis was those of subependymal nodules which were best seen on short repetition time (TR) spin-echo images. Hypointensities within the nodules consistent with calcification were most evident on long TR images. Contrast enhancing lesions, indicative subependymal giant cell astrocytoma, occurred in four cases. Cortical tubers (n = 11) and white matter lesions (n = 8) exhibited long T1 and T2 relaxation characteristics although reversed pattern was noted in one newborn patient. Cortical tubers and white matter lesions had more irregular shapes in early childhood patients. MR imaging is the sensitive method in detection of gyral tubers and white matter lesions and also valuable in detecting giant cell astrocytoma

  13. Arthroscopic findings after shoulder dislocation

    Medenica Ivica

    2009-01-01

    Full Text Available Background/Aim. Recurrent instability of the shoulder joint is frequently difficult to differentiate from diseased or injured rotator cuff or tendon of the forearm flexor (m. biceps brachii. Shoulder joint arthroscopy has been only recently introduced into instable shoulder joint lesion examination. The aim of this study was to present and analyze an arthroscopic finding on instable shoulder joint in order to determine causes and mechanisms of instability, as well as principles of surgical treatment. Methods. Arthroscopy of the shoulder joint was performed in 158 patients with at least one documented shoulder joint dislocation. These patients were divided into two groups. The group I included the patients with one to three dislocations, while the group II those with more than three dislocations. Preoperative diagnosis was based on anamnestic data and clinical examination using specific tests, and on the diagnosis of shoulder joint using radiography or computed tomography. Results. Out of the total number of the patients 138 (87.34% had injury of the anterior patellar brim, 119 (75.32% had failure of the anterior capsule, 126 (79.75% had compressive cartilage injury of the posterior part of the head of the upper arm bone (Hill-Sachs lesion, 102 (64.56% had insufficiency of glenohumeral tendon, 11 (6.96 had complete cut of the rotator cuff, 23 (14.56% had injury of the posterior patellar brim, 12 (7.59% had injury of the upper anterior-posterior patellar brim (SLAP. Conclusion. According to the obtained results it could be concluded that there is no a unique injury that leads to shoulder joint instability. It is necessary to point out to the significance of anamnesis and clinical examination in making diagnosis. Arthroscopic diagnostics is indicated in clinically unreliable findings as an additional method for determining operative treatment.

  14. Initial findings from a mixed-methods evaluation of computer-assisted therapy for substance misuse in prisoners: Development, implementation and clinical outcomes from the ‘Breaking Free Health & Justice’ treatment and recovery programme

    Sarah Elison

    2015-08-01

    examine the processes of implementation of this novel digital health programme and the various barriers and facilitators of this, including the practicalities of providing an online treatment programme in an environment in which there are multiple, complex security requirements and considerations. Additionally, the acceptability of the BFHJ programme to prisoners who may have limited experience of using online technologies was also explored. Clinical outcomes in terms of the programmes impact on substance dependence and use were also examined. Methods: In line with the Medical Research Council (MRC guidelines around development and evaluation of complex interventions (Craig et al., 2008, a mixed-methods approach was used including a qualitative study to explore the implementation of this online treatment programme within the secure prison environment, and offender perceptions of this novel, technology-enhanced approach to substance misuse treatment. In addition, quantitative data derived from a battery of standardised psychometric assessments was used to examine clinical effectiveness of BFHJ. Results: In order to meet MoJ security requirements prior to implementation, the BFHJ programme had to be reviewed and ‘white listed’ by NOMS and their security partner XMA to ensure the programme met all security, quality and information assurance processes and standards. This was a lengthy and costly process that entailed freshly developing the programme in partnership with VC experts at NOMS to ensure the programme is ‘sterile’ i.e., there are no holes in the system or links to external websites – this comprised some aspects of the programme content and resulted in some clinical techniques requiring reworking e.g., removing Google maps from one section of the programme. Themes emerging from qualitative data around offenders experiences of BFHJ illustrate its potential for use in prison settings and also to provide, for the first time, genuine continuity of care during

  15. MR findings of polymyositis / dermatomyositis

    The purpose of this study was to evaluate the MR findings and useful sequences in Polymyositis/ Dermatomyositis, and to correlate MR findings with disease activity. Materials and Methods: The study included nine clinically proven cases of Polymyositis/Dermatomyositis, eight involving the thigh and one, the shoulder (2 cases, 1 follow-up). The contrast between affected and normal muscles and difference in signal intensity ratio in the muscle groups were retrospectively evaluated on Gd-enhanced T1WI and T2WI. We also evaluated the magnitude of involvement of muscle groups, fatty replacement of muscle and change of subcutaneous fat layer, and correlated signal intensity ratio with serum level of muscle enzymes. Differences in signal intensity ratio and the frequency of chemical shift artifact were evaluated on T2WI as active and inactive groups classified according to clinical findings, and the chemical shift artifact was correlated with the finding of Gd-enhanced T1WI. Except in the case of one shoulder, statistical analysis was assessed by the Anova test and-test. Results: On Gd-enhanced T1WI and T2WI contrast was 0.54 and 0.82, respectively and p value was 0.02. With regard to difference in signal intensity ratios of muscle groups, as seen on Gd-enhanced T1WI and T2WI, p valves were 0.07 and < 0.01, respectively. Muscle involvement was thus clearly visualized on T2WI. The order of frequency of involved muscle groups was vastus muscles, gluteus maximus, sartorius muscles, adductor muscles, gracilis muscle, and hamstring muscles. Fatty replacement and subcutaneous fatty change were visualized in five cases and one, respectively. The correlation coefficient between the signal intensity seen on T2WI and muscle enzymes was 0.59 (CPK) and 0.52 (LDH). The chemical-shift artifact was detected in both clinical groups (four active two inactive) and corresponded to one case of muscle involvement and five of perimuscular edema, as seen on Gd-enhanced T1WI. Conclusion: T2WI is

  16. Findings.

    Viadero, Debra; Coles, Adrienne D.

    1998-01-01

    Studies on race-based admissions, sports and sex, and religion and drugs suggest that: affirmative action policies were successful regarding college admissions; boys who play sports are more likely to be sexually active than their peers, with the opposite true for girls; and religion is a major factor in whether teens use cigarettes, alcohol, and…

  17. A dose-finding, long-term study on the use of calcium chloride in saline solution as a method of nonsurgical sterilization in dogs: evaluation of the most effective concentration with the lowest risk

    Leoci, Raffaella; Aiudi, Giulio; Silvestre, Fabio; Lissner, Elaine A; Marino, Fabio; Lacalandra, Giovanni M

    2014-01-01

    Background Canine overpopulation is a global issue with serious health and welfare implications. Nonsurgical methods of sterilization could yield positive impacts on this problem, but no long-term data on such methods are available. The objective of the current investigation was to determine the effects of intratesticular injections of calcium chloride dihydrate (CaCl2) in saline in dogs over a one year period. Five concentrations (0%, 10%, 20%, 30%, 60%) of CaCl2 in saline were administered ...

  18. Chronic eosinophilic pneumonia: CT findings

    Objective: To assess the usefulness of computerized tomography (CT) in the diagnosis of chronic eosinophilic pneumonia. Material and Methods: A double helical CT was performed in 6 patients referred to our center because of a chest X-ray with pulmonary infiltrates. Clinical presentation was cough, fever and eosinophilia in peripheral blood. Patients' age ranged from 25 to 55 years; 4 were women and 2 were men, one of the latter had a history of bronchial asthma. All patients received treatment with corticosteroids, with remission of the clinical and radiological parameters. Three patients underwent a control CT. Results: Findings consisted in focal parenchymal alterations, with areas of pulmonary consolidation and areas of 'ground glass' appearance; both patterns coexisted in certain areas. In 3 cases the lesions extended from the apices to the pulmonary bases, with predominance of the upper and middle fields. In 1 patient, there was frank predominance in the left hemi thorax. In another patient, who had a history of asthma, there were signs of pulmonary hyperinflation, with diffuse thickening of the bronchial walls, added to the previously mentioned findings, which involved the entire lung. In the mediastinum, 1 patient had lymph nodes larger than 1 cm, 3 had lymph nodes that were not enlarged but were more numerous than usual, and in the remaining patients no lymph nodes were found. The control CT's showed almost total resolution of the pulmonary infiltrates. Conclusion: The combination of eosinophilia and characteristic pulmonary infiltrates with a likely clinical presentation, associated with an optimal response to treatment with corticosteroids allows to make a reliable diagnosis and avoids the need for a pulmonary biopsy. (author)

  19. CT findings of Wilson's disease

    Thirteen cases of Wilson's disease were examined by computerized tomography. Two of them were latent cases. The other 11 were typical cases with a Kayser-Fleisher ring and neurological signs, and in which the ceruloplasmin level in serum was low. The caudate heads were measured by Barr's method using two ratios, FH/CC and CC/OT. The CT findings were as follows: (1) caudate head atrophy (10 cases), (2) cerebral atrophy and/or ventricular dilatation (7 cases), (3) symmetrical low density of thalamus (3 cases), (4) symmetrical low density of pallidum (2 cases), (5) low density of midbrain (2 cases), (6) symmetrical low density of putamen (1 case), (7) pons atrophy (1 case), (8) cerebellar atrophy (1 case), (9) low density of r-temporal area (1 case). All of them except for the two latent cases showed some abnormal findings on CT. Only one symptomatic case showed no caudate atrophy one year after the onset, though two other cases already showed marked atrophy after only 10 months. It was stressed that the low-density lesions in the thalamic area were found with a high frequency. There was no correlation between the duration of illness and the degree of caudate atrophy among the patients with Wilson's disease as compared with those with Huntington's chorea. As in a previous study of pneumoencephalography, we failed also to distinguish the two diseases by measuring the ratios on CT films. It may be valuable to study the progression of the CNS lesions of Wilson's disease by using CT repeatedly. (author)

  20. Computed Tomography Findings in Xanthogranulomatous Pyelonephritis

    Arumugam Rajesh; George Jakanani; Nick Mayer; Kevin Mulcahy

    2011-01-01

    Background: Xanthogranulomatous pyelonephritis (XGN) is an uncommon condition characterized by chronic suppurative renal inflammation that leads to progressive parenchymal destruction. Purpose: To review the computed tomography (CT) findings of patients diagnosed with XGN. Materials and Methods: A retrospective review of CT findings in patients with histologically proven XGN was carried out. Results: Thirteen CT examinations of 11 patients were analyzed. Renal enlargement was demonstrable on ...

  1. A method to search for bulk motions in the ICM with {\\sl Chandra} CCD spectra: application to the Bullet cluster

    Liu, Ang; Tozzi, Paolo; Zhu, Zong-Hong

    2015-01-01

    We propose a strategy to search for bulk motions in the intracluster medium (ICM) of merging clusters based on {\\sl Chandra} CCD data. Our goal is to derive robust measurements of the average redshift of projected ICM regions obtained from the centroid of the $K_\\alpha$ line emission. We thoroughly explore the effect of the unknown temperature structure along the line of sight to accurately evaluate the systematic uncertainties on the ICM redshift. We apply our method to the "Bullet cluster" (1E~0657-56). We directly identify 23 independent regions on the basis of the surface brightness contours, and measure the redshift of the ICM averaged along the line of sight in each. We find that the redshift distribution across these regions is marginally inconsistent with the null hypothesis of a constant redshift or no bulk motion in the ICM, at a confidence level of about $2\\, \\sigma$. We tentatively identify the regions most likely affected by bulk motions and find a maximum velocity gradient of about $(46\\pm 13)$ ...

  2. APPLICATION OF THE MULTIRESPONSE OPTIMISATION SIMPLEX METHOD TO THE BIODIESEL - B100 OBTAINING PROCESS

    Julyane Karolyne Teixeira da Costa

    2016-03-01

    Full Text Available The process of obtaining B100 biodiesel from vegetable oil and animal fat mixtures by transesterification under basic conditions was optimised using the super-modified simplex method. For simultaneous optimisation, yield, cost, oxidative stability and Cold Filter Plugging Point (CFPP, were used as responses, and the limits were established according to the experimental data and the conformity parameters established by legislations. Based on the predictive equations obtained from the simplex-centroid design-coupled functions, the multi-response optimisation showed an optimal formulation containing 38.34 % soybean oil, 21.90 % beef tallow and 39.25 % poultry fat. The validation showed that there are no significant differences between the predicted and experimental values. The simplex-centroid mixture design and simplex optimisation methods were effective tools in obtaining biodiesel B100, using a mixture of different raw materials.

  3. MR findings in intralabyrinthine schwannomas

    Montague, Mary-Louise; Kishore, Ameet; Hadley, Donald M.; O' Reilly, Brian

    2002-05-01

    AIM: Intralabyrinthine schwannomas (ILS) are rare benign tumours. They are not always recognized on routine magnetic resonance imaging (MRI). We aimed to study the clinical presentation and MRI findings in our patients with ILS. MATERIALS AND METHODS: Retrospective analysis of patients with vestibular schwannomas treated at this center. RESULTS: Of 144 vestibular schwannomas studied at this centre, three patients had an ILS. The most common presenting symptoms were unilateral hearing loss, tinnitus and vertigo. Two patients demonstrated a progressive sensorineural hearing loss (SNHL). The third patient had a severe SNHL at presentation. MRI enhanced with contrast medium was positive in the two patients with progressive SNHL and negative in the patient with the severe SNHL. CONCLUSION: This series demonstrates the ability of MRI to identify schwannomas filling the labyrinth, and also its inability to identify extremely small ILS. It underlines the importance of sending the cristae of patients undergoing labyrinthectomy for presumed Meniere's disease for histological examination. Montague, M.-L. et al. (2002)

  4. Correlation of Imaging Findings with Pathologic Findings of Sclerosing Adenosis

    Choi, Bo Bae; Shu, Kwang Sun [Chungnam National University Hospital, Daejeon (Korea, Republic of)

    2012-03-15

    The purpose of this study was to evaluate the mammographic and sonographic findings of pure sclerosing adenosis. We retrospectively reviewed the mammographic and sonographic findings in 40 cases of pure sclerosing adenosis confirmed by core needle biopsy (n = 23), vacuum-assisted biopsy (n = 7), excision biopsy (n = 9), and lumpectomy (n = 1) from January 2002 to March 2010. All imaging findings were analyzed according to the American College of Radiology (ACR) breast imaging reporting and data system (BI-RADS). Radiologic features were correlated with pathologic findings. Although most mammograms showed negative findings (57%), calcification was the most common abnormal finding of sclerosing adenosis. On sonography, the most common finding was a circumscribed oval hypoechoic mass without posterior features (78%). Most masses showed BI-RADS category 3, (75%, 27/36). Five cases showed categories 4 or 5 (14%, 5/36). Most mammographic and sonographic findings of sclerosing adenosis are non-specific and non-pathognomonic, even though sometimes sclerosing adenosis can be radiologically or histopathologically confused with malignancy

  5. Force Finding of Tensegrity Cable Domes --Imbalance Force Iterative Method%索穹顶结构的找力分析方法--不平衡力迭代法

    阚远; 叶继红

    2006-01-01

    索穹顶的刚度和承载能力都是通过施加预应力来获取的,预应力设计是对索穹顶进行任何其它分析的基础,所以它的找力分析(Force finding)是一项很重要的工作.本文提出一种找力分析方法--不平衡力迭代法,它可以克服整体可行预应力法的一些不足:即使在索穹顶构件分组发生错误时仍可找到满足已知形状的预应力分布,并且该方法具有良好的稳定性和运算效率,算例表明不平衡力迭代法非常适合大型复杂索穹顶结构的找力分析.

  6. An Investigation of the Academic Information Finding and Re-finding Behavior on the Web

    Hsiao-Tieh Pu

    2014-12-01

    Full Text Available Academic researchers often need and re-use relevant information found after a period of time. This preliminary study used various methods, including experiments, interviews, search log analysis, sequential analysis, and observation to investigate characteristics of academic information finding and re-finding behavior. Overall, the participants in this study entered short queries either in finding or re-finding phases. Comparatively speaking, the participants entered greater number of queries, modified more queries, browsed more web pages, and stayed longer on web pages in the finding phase. On the other hand, in the re-finding phase, they utilized personal information management tools to re-find instead of finding again using search engine, such as checking browsing history; moreover, they tend to input less number of queries and stayed shorter on web pages. In short, the participants interacted more with the retrieval system during the finding phase, while they increased the use of personal information management tools in the re-finding phase. As to the contextual clues used in re-finding phase, the participants used less clues from the target itself, instead, they used indirect clues more often, especially location-related information. Based on the results of sequential analysis, the transition states in the re-finding phase was found to be more complex than those in the finding phase. Web information finding and re-finding behavior is an important and novel area of research. The preliminary results would benefit research on Web information re-finding behavior, and provide useful suggestions for developing personal academic information management systems. [Article content in Chinese

  7. On König's root finding algorithms

    Buff, Xavier; Henriksen, Christian

    2003-01-01

    In this paper, we first recall the definition of a family of root-finding algorithms known as König's algorithms. We establish some local and some global properties of those algorithms. We give a characterization of rational maps which arise as König's methods of polynomials with simple roots. We...... then estimate the number of non-repelling cycles König's methods of polynomials may have. We finally study the geometry of the Julia sets of König's methods of polynomials and produce pictures of parameter spaces for König's methods of cubic polynomials....

  8. Krabbe disease: unusual MRI findings

    Nagar, Veena A.; Ursekar, Meher A.; Krishnan, Pradeep; Jankharia, Bhavin G. [Jankharia Imaging Centre, Mumbai (India)

    2006-01-01

    We present the MRI findings in a case of infantile-onset Krabbe disease. Enlargement of the intracranial optic nerves and cervical cord were detected in addition to more typical changes in the cerebral white matter and thalami. We also review the proton MR spectroscopic findings in Krabbe disease. (orig.)

  9. MRI Findings In Dengue Encephalitis

    Ashraf V.V

    2004-01-01

    Full Text Available Neurological manifestations are rare in dengue fever. Two cases with encephalopathy and systemic features of dengue fever with abnormal CSF and MR imaging are reported. Striking MRI finding was bilateral symmetrical thalamic lesions similar to those reported in Japanese encephalitis. This report highlights that MRI findings can be similar in dengue and Japanese encephalitis.

  10. Empirical Findings and Educational Policies.

    Kotter, Ludwig

    1988-01-01

    Sketches relevant issues of the relationship between findings in the field of educational science and decisions to be taken in educational policy. Discusses possible interaction models, identifying factors relevant to their realization. States that the identification of factors determining the application of research findings remains an important…

  11. Post-therapeutic imaging findings

    Pollice, Saverio, E-mail: saveriopollice@hotmail.it [Department of Radiology and Neuroradiology, “L. Bonomo Hospital”, 76123 Andria, BT (Italy); Muto, Mario, E-mail: mutomar@tiscali.it [Department of Neuroradiology, “Cardarelli Hospital”, Naples (Italy); Scarabino, Tommaso, E-mail: tscarabino@hotmail.com [Department of Radiology and Neuroradiology, “L. Bonomo Hospital”, 76123 Andria, BT (Italy)

    2015-05-15

    Highlights: • This study is the result of collaboration between neuroradiologists and neurosurgeons. • Comparison between neuroimaging techniques to better evaluate the complications after treatment of the spin. • Evaluation of the imaging features of complications and definition of follow-up. - Abstract: Any surgical approach modifies the normal anatomical and functional arrangement of the segmental spine which is aimed, therefore image interpretation cannot ignore a correct set of knowledge in the field of anatomy, pathophysiology, drug compliance, interventional radiology and surgery. Neuroradiological imaging has an important role before surgery to direct the surgeon or interventional radiologist during the operation, both in post-surgery, where imaging examination can rightly evaluate properties and effects of the treatment and can detect potential complications as infections, abscess, bleeding, exuberant scar, mobilization and rupture of devices. The available methods of imaging are the X-rays (XR) made at least in two projections, Computed Tomography (CT) with MPR (multiplanar) and VR (volume rendering) reconstruction, and Magnetic Resonance (MR), often performed before and after contrast media injection. Imaging assessment of spine after surgery is complex and depends upon several factors, including surgical procedures and disease for which it was performed; biomechanical of the underlying cortical and cancellous bone findings; conditions of muscles, intervertebral disk and ligaments; time since surgery procedures; duration and nature of the post-surgical syndrome. Depending upon several factors, one or a combination of complementary imaging modalities (X-rays, Computed Tomography, Magnetic Resonance) may be required to evaluate effectiveness of the treatment; to demonstrate any clinically relevant abnormality at the treated region and adjacent structures (complications such as inflammation, abscesses, bleeding and misplacement of the device); to

  12. Thoracic Computed Tomography Findings in Malignant Mesothelioma

    Omer Tamer Dogan

    2012-01-01

    Full Text Available Background: Malignant pleural mesothelioma (MPM is an uncommon neoplasm. MPM occurs more frequently in patients born or living in certain villages of Turkey.Objectives: We aimed to review radiological findings of MPM.Patients and Methods: We reviewed the CT findings in 219 biopsy-proven MPM patients admitted to our clinic between 1993 and 2008.Results: The most common CT findings included pleural thickening (n=197, 90% classified as diffuse (n=138, 63%, nodular (n=49, 22% and mass-type (n=16, 7%. Pleural effusion was found in 173 patients (79%, involvement of the interlobar fissures in 159 (73%, mediastinal pleural involvement in 170 (78%, volume contraction in 142 (65%, mediastinal shift in102 (47% and mediastinal lymphadenopathy in 54 (25%.Conclusion: MPM may present with diverse radiological features. Pleural thickening and pleural effusion were the most frequent radiological findings. Thoracic CT scans might be assessed more cautiously in patients with environmental exposure to asbestos.

  13. Ultrasonographic findings of testicular tumors: Correlation with pathologic findings

    Lee, Yong Joo; Koh, Byung Hee; Oh, Jae Cheon; Kim, Bong Soo; Kim, Yong Soo; Rhim, Hyen Chul; Cho, On Koo; Hahm, Chang Kok; Park, Hae Young; Lee, Jung Dal [Hanyang University College of Medicine, Seoul (Korea, Republic of)

    1999-03-15

    Scrotal sonography is a valuable tool for assessing the testis and surrounding structures, and has become the imaging modality of choice for evaluation of the scrotum. Scrotal sonography is also helpful for differentiating cystic from slid mass and testicular from extratesticular mass, but is sometimes difficult in differentiating malignant tumor from various benign conditions such as epidermoid cyst, focal orchitis, testicular hematoma, and abscess. We demonstrate the sonographic findings of the various testicular mass, and correlation with pathologic findings.

  14. Finding Maximal Pairs with Bounded Gap

    Brodal, Gerth Stølting; Lyngsø, Rune B.; Pedersen, Christian N. S.;

    1999-01-01

    A pair in a string is the occurrence of the same substring twice. A pair is maximal if the two occurrences of the substring cannot be extended to the left and right without making them different. The gap of a pair is the number of characters between the two occurrences of the substring. In this...... paper we present methods for finding all maximal pairs under various constraints on the gap. In a string of length n we can find all maximal pairs with gap in an upper and lower bounded interval in time O(n log n+z) where z is the number of reported pairs. If the upper bound is removed the time reduces...... to O(n+z). Since a tandem repeat is a pair where the gap is zero, our methods can be seen as a generalization of finding tandem repeats. The running time of our methods equals the running time of well known methods for finding tandem repeats....

  15. Integrated method for adaptability and phenotypic stability analysis = Método integrado para análise de adaptabilidade e estabilidade fenotipica

    Edmar Soares Vasconcelos; Múcio Silva Reis; Cosme Damião Cruz; Tuneo Sediyama; Carlos Alberto Scapim

    2011-01-01

    The objectives of this study were a description of the Centroid Method, which is used to investigate the phenotypic adaptability of genotypes and the inclusion of new ideotypes therein, creating the Integrated Method for adaptability and phenotypic stability analysis, as well as a comparison of the two methods in a study example. As an applied example of the new proposal, grain yield data of 14 soybean genotypes from experiments at four locations in the state of Minas Gerais were used. In a c...

  16. Can the Onset of Type 2 Diabetes Be Delayed by a Group-Based Lifestyle Intervention in Women with Prediabetes following Gestational Diabetes Mellitus (GDM? Findings from a Randomized Control Mixed Methods Trial

    Angela O’Dea

    2015-01-01

    Full Text Available Objective. To evaluate a 12-week group-based lifestyle intervention programme for women with prediabetes following gestational diabetes (GDM. Design. A two-group, mixed methods randomized controlled trial in which 50 women with a history of GDM and abnormal glucose tolerance postpartum were randomly assigned to intervention (n=24 or wait control (n=26 and postintervention qualitative interviews with participants. Main Outcome Measures. Modifiable biochemical, anthropometric, behavioural, and psychosocial risk factors associated with the development of type 2 diabetes. The primary outcome variable was the change in fasting plasma glucose (FPG from study entry to one-year follow-up. Results. At one-year follow-up, the intervention group showed significant improvements over the wait control group on stress, diet self-efficacy, and quality of life. There was no evidence of an effect of the intervention on measures of biochemistry or anthropometry; the effect on one health behaviour, diet adherence, was close to significance. Conclusions. Prevention programmes must tackle the barriers to participation faced by this population; home-based interventions should be investigated. Strategies for promoting long-term health self-management need to be developed and tested.

  17. Approximate path integral methods for partition functions

    We review several approximate methods for evaluating quantum mechanical partition functions with the goal of obtaining a method that is easy to implement for multidimensional systems but accurately incorporates quantum mechanical corrections to classical partition functions. A particularly promising method is one based upon an approximation to the path integral expression of the partition function. In this method, the partition-function expression has the ease of evaluation of a classical partition function, and quantum mechanical effects are included by a weight function. Anharmonicity is included exactly in the classical Boltzmann average and local quadratic expansions around the centroid of the quantum paths yield a simple analytic form for the quantum weight function. We discuss the relationship between this expression and previous approximate methods and present numerical comparisons for model one-dimensional potentials and for accurate three-dimensional vibrational force fields for H2O and SO2

  18. Chest radiographic findings of leptospirosis

    1. A study on chest radiographic findings of 54 cases with pneumonia like symptoms was performed. Of 54 cases, 8 cases were confirmed to be leptospirosis and 7 cases were leptospirosis combined with Korean hemorrhagic fever. 2. Of 8 cases of leptospirosis, 4 cases showed abnormal chest radiographic findings: acinar nodular type 2, massive confluent consolidation type 2. Of 7 cases of leptospirosis combined with Korean hemorrhagic fever: acinar nodular type 3, massive confluent consolidation type 1, and increased interstitial markings type 1 respectively. 3. It was considered to be difficult to diagnose the leptospirosis on chest radiographic findings alone, especially the case combined with Korean hemorrhagic fever.

  19. CT findings of pulmonary aspergillosis

    Cheon, Jung Eun; Im, Jung Gi; Goo, Jin Mo; Kim, Hong Dae; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1995-10-15

    The fungus aspergillus can cause a variety of pulmonary disorders. Aspergilloma is a noninvasive aspergillus colonization of virtually any type of preexisting pulmonary cavity or cystic space. Invasive pulmonary aspergillosis is serious, usually fatal infection in patients being treated with immunosuppressants or who have chronic debilitating disease. Allergic bronchopulmonary aspergillosis is characterized clinically by asthma, blood and sputum eosinophilia and positive immunologic reaction to aspergillus antigen. Awareness of the radiographic and CT findings of pulmonary aspergillosis is important in making the diagnosis of aspergillus-caused pulmonary disorders. In this pictorial essay, we illustrated various radiological findings of pulmonary aspergillosis focused on CT findings correlated with gross pathologic specimens.

  20. Chest radiographic findings of leptospirosis

    Kim, Mee Hyun; Jung, Hee Tae; Lee, Young Joong; Yoon, Jong Sup [Hallym University College of Medicine, Seoul (Korea, Republic of)

    1986-04-15

    1. A study on chest radiographic findings of 54 cases with pneumonia like symptoms was performed. Of 54 cases, 8 cases were confirmed to be leptospirosis and 7 cases were leptospirosis combined with Korean hemorrhagic fever. 2. Of 8 cases of leptospirosis, 4 cases showed abnormal chest radiographic findings: acinar nodular type 2, massive confluent consolidation type 2. Of 7 cases of leptospirosis combined with Korean hemorrhagic fever: acinar nodular type 3, massive confluent consolidation type 1, and increased interstitial markings type 1 respectively. 3. It was considered to be difficult to diagnose the leptospirosis on chest radiographic findings alone, especially the case combined with Korean hemorrhagic fever.

  1. Pollution! Find a STEM solution!

    Takač, Danijela; Moćan, Marina

    2016-04-01

    Primary and secondary school Pantovčak is an innovative school in downtown Zagreb, Croatia. The school is involved in many projects concerning STEM education. Pollution! Find a STEM solution! is a two year long cross-curricular project that grew out of identified need to develop STEM and ICT skills more. Pisa results make evident that students' knowledge is poor and motivation for math and similar subjects is low. Implying priorities of European Commission, like e-learning, raises motivation and also develops basic skills and improves knowledge in science, math, physic, ICT. Main objectives are to increase students' interest in STEM education and careers and introduce them to all available new trends in technology, engineering and science in their region by visiting clean technology industries and strengthening links with them, to introduce some future digital jobs and prepare students for rapid technological changes by integrating ICT into classroom practice more, to highlight the importance of global environmental issues and improve the knowledge in the areas of sustainable development and renewable energy, to develop collaborative partnership between schools and the wider community in formal, non-formal and informal learning, to support multilingualism by publishing Open Educational Resources in 8 different languages and to strengthen the professional profile of the teaching profession. The project brings together 231 teachers and 2729 students from five different European countries in learning to think globally and work on activities that contribute to the community's well-being. There are altogether 33 activities, divided in 4 categories. STEM activities are focused on students building the devices for measuring air, light and noise pollution in their school and homes. They use the scientific method to analyze the data and compare the results with their peers to find a solution. Eskills, digital literacy and digital jobs are focused on introducing career

  2. Finding an Eye Care Professional

    ... care specialist. Call the department of ophthalmology or optometry at a nearby hospital or university medical center. ... at 610-664-1175. The American Board of Optometry provides an online “Find a Board-Certified Optometrist” ...

  3. Dermoscopy Findings of Hidroacanthoma Simplex

    Yota Sato

    2014-05-01

    Full Text Available Hidroacanthoma simplex (HAS, also known as intraepidermal eccrine poroma, is a rare eccrine adnexal tumor that tends to be misdiagnosed as other types of benign skin tumor, including clonal seborrheic keratosis. Notably, HAS is sometimes misdiagnosed and treated by cryosurgery as seborrheic keratosis, which could trigger the later development of porocarcinoma. Therefore, accurate diagnosis of HAS is indispensable for dermatologists to avoid the development of malignant tumors by an unsuitable treatment. In this report, we present the characteristic dermoscopy findings of HAS. Indeed, the dermoscopy findings might be related to the melanin-rich necrotic cells in the epidermis, which are quite different from dermoscopy findings of clonal seborrheic keratosis. As a previous report suggested, it is difficult for a dermatologist to differentiate HAS from clonal seborrheic keratosis by the naked eye. Our findings might be supportive for the early diagnosis of HAS.

  4. Roentgen findings in cheirolumbar dysostosis

    Constitutional stenosis of the lumbar vertebral canal and brachycheiria (brachymetacarpia/brachyphalangia) together form cheirolumbar dysostosis (no. 2692 of the Birth Defects Encyclopedia, 1987). Typical findings in the basic type and transitional forms are presented. (orig.)

  5. Global optimization for track finding

    Hopfield networks with mean-field annealing have been proposed for track finding in particle detectors by Peterson and Denby. In this paper we investigate and compare some other - probabilistic and heuristic - approaches to finding the global minimum of the associated energy function: Simulated annealing, threshold accepting, great deluge, record-to-record travel, and tabu search. We also use a branch-and-bound and a branch-and-cut algorithm in order to obtain the exact global minimum. (orig.)

  6. MR findings of synovial sarcoma

    MR images of seven patients with histologically documented synovial sarcoma were reviewed to find the suggestive or pathognomonic findings of the disease. MR appearance of the tumor was inhomogeneous, multisepatated mass with various degree of internal septation and infiltrative tumor margin. The signal intensity of the mass was slightly hyperintense relative to muscle on T1-weighted image and hyperintense relative to subcutaneous fatty tissue on T2-weighted image

  7. MR findings of synovial sarcoma

    Lee, Jin Joo; Byun, Hong Sik; Kim, Kie Hwan; Yoon, Il Yoon; Chin, Soo Yil [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1993-09-15

    MR images of seven patients with histologically documented synovial sarcoma were reviewed to find the suggestive or pathognomonic findings of the disease. MR appearance of the tumor was inhomogeneous, multisepatated mass with various degree of internal septation and infiltrative tumor margin. The signal intensity of the mass was slightly hyperintense relative to muscle on T1-weighted image and hyperintense relative to subcutaneous fatty tissue on T2-weighted image.

  8. CT findings of exophageal perforation

    Heo, Jeong Nam; Choi, Yo Won; Jeon, Seok Chol; Park, Choong Ki; Hahm, Chang Kok [Hanyang University College of Medicine, Seoul (Korea, Republic of)

    2002-09-01

    To determine which CT findings are useful for the early disgnosis of esophageal perforation, and on the basis of these findings, to assess the accuracy of prediction of the perforation site. A review of medical records indicated that between January 1995 and December 2001, 36 patients with esophageal perforation were admitted to our hospital. Thirteen of these [M:F=8:5, age; 28-69 (mean, 52.4) years], who had undergone CT chest scanning, were included in this study. The causes of esophageal perforation were trauma (n=5), infectious diseases (n=4), Boerhaave syndrome (n=1), lung cancer (n=1), esophageal cancer (n=1), and idiopathic. Two chest radiologists unaware of the clinical findings reviewed the CT scans and predicted whether the upper or lower esophagus was perforated. The most common CT finding was extraluminal air at the posterior mediastinum (n=11), while other findings included pulmonary consolidation (n=10), pleural effusion (n=7), discontinuity of the esophageal wall (n=6) and subcutaneous emphysema (n=4), fluid collection around the esophagus (n-4), esophageal wall thickening (n=4), pneumothorax (n=2), and lung abscess (n=2). The perforation site was accurately predicted in 76.9% of cases (10/13). The CT findings which help the diagnosis of esophageal perforation, and prediction of the sites at which it occurs, are extraluminal air of fluid collection, focal defect of the esophageal wall, and esophageal wall thickening.

  9. Radiologic findings of granulomatous mastitis

    The describe the radiologic findings of granulomatous mastitis of the breast. This study included 19 patients (age range: 22 to 56 years; mean 37 years) with 22 lesions that were pathologically confirmed as having granulomatous mastitis. All the patients underwent a breast ultrasonography and 13 patients underwent a mammography. The results of the mammography revealed focal asymmetry (n = 9), multiple ill-defined isodense nodules (n 2), ill-defined nodular density on craniocaudal view (n = 1), and unremarkable finding (n = 1). The sonographic findings included continuous or discontinuous multiple tubular and nodular low echoic lesions (n = 7), ill-defined heterogeneously low echoic lesion (n = 5), irregular-shaped, ill-defined low echoic mass (n = 4), fluid collection with internal floating materials suggesting the presence of an abscess (n = 4), ill-defined heterogeneously low echoic lesion and abscess (n = 1), and multiple ill-defined nodules (n = 1). In the case of granulomatous mastitis, the mammography results indicate a lack of specificity between normal findings and focal asymmetry. The sonographic findings indicate that ill-defined heterogeneously low echoic lesions or irregular shaped, ill-defined low echoic masses are difficult to differentiate from breast cancer. The sonographic findings of abscesses indicate a difficulty in differentiating them from cases of pyogenic mastitis. However, multiple tubular and nodular low echoic lesions, especially with a continuous appearance, should point to granulomatous mastitis, and is helpful in its differential diagnosis and treatment

  10. Radiologic findings of granulomatous mastitis

    Kim, Tae Gyu; Kim, Ji Young; Jeong, Myeong Ja; Kim, Jae Hyung; Kim, Soung Hee; Kim, Soo Hyun; Jun, Woo Sun; Park, Kyeong Mee; Han, Se Hwan [Paik Hospital, Inje University College of Medicine, Seoul (Korea, Republic of)

    2008-08-15

    The describe the radiologic findings of granulomatous mastitis of the breast. This study included 19 patients (age range: 22 to 56 years; mean 37 years) with 22 lesions that were pathologically confirmed as having granulomatous mastitis. All the patients underwent a breast ultrasonography and 13 patients underwent a mammography. The results of the mammography revealed focal asymmetry (n = 9), multiple ill-defined isodense nodules (n 2), ill-defined nodular density on craniocaudal view (n = 1), and unremarkable finding (n = 1). The sonographic findings included continuous or discontinuous multiple tubular and nodular low echoic lesions (n = 7), ill-defined heterogeneously low echoic lesion (n = 5), irregular-shaped, ill-defined low echoic mass (n = 4), fluid collection with internal floating materials suggesting the presence of an abscess (n = 4), ill-defined heterogeneously low echoic lesion and abscess (n = 1), and multiple ill-defined nodules (n = 1). In the case of granulomatous mastitis, the mammography results indicate a lack of specificity between normal findings and focal asymmetry. The sonographic findings indicate that ill-defined heterogeneously low echoic lesions or irregular shaped, ill-defined low echoic masses are difficult to differentiate from breast cancer. The sonographic findings of abscesses indicate a difficulty in differentiating them from cases of pyogenic mastitis. However, multiple tubular and nodular low echoic lesions, especially with a continuous appearance, should point to granulomatous mastitis, and is helpful in its differential diagnosis and treatment.

  11. Near-Earth objects finding them before they find us

    Yeomans, Donald K

    2012-01-01

    Of all the natural disasters that could befall us, only an Earth impact by a large comet or asteroid has the potential to end civilization in a single blow. Yet these near-Earth objects also offer tantalizing clues to our solar system's origins, and someday could even serve as stepping-stones for space exploration. In this book, Donald Yeomans introduces readers to the science of near-Earth objects--its history, applications, and ongoing quest to find near-Earth objects before they find us. In its course around the sun, the Earth passes through a veritable shooting gallery of million

  12. Imaging findings of xanthogranulomatous pyelonephritis

    To define the imaging patterns of xanthogranulomatous pyelonephritis (XGP). The demographic, clinical, and imaging findings of 21 cases of pathologically proven XGP in 20 patients (bilateral in one) were evaluated. The findings of ultrasonography and CT were retrospectively evaluated with regard to distribution and extent of the disease, kidney size, the presence of calculi, hydronephrosis, and renal function. The findings were assessed by two radiologists, who established a consensus. Imaging and pathologic findings were compared. Sixteen of the 20 patients were female, and 19 were adults. Their age ranged from 3 to 16 (mean, 45) years. In all patients except one, the disease was unilateral (right: left =3D 13 :16). In one patient, XGP was bilateral, and there were thus 21 cases. Seventeen (81%) of these were diffuse, and four (19%) were focal; extrarenal extension occurred in 13 cases (62%), among which ipsilateral pleural effusion was noted in two. The kidney was enlarged diffusely in 12 cases (57%), and focally in three (14%); urinary calculi were present in 16 cases (76%), with staghorn calculi in four of these; and hydronephrosis occurred in 17 (81%). Impairment of ipsilateral renal function was noted in 13 cases (62%). Clinical findings of inflammation such as fever, pyuria, bacteriuria, or leucocytosis were noted in all patients. In addition to nephromegaly, renal function impairment, and urinary obstruction due to calculi, which are typical features of XGP, the condition may also show variable imaging findings. If the images obtained in the case of a middle-aged woman with clinical findings of urinary infection are atypical, we believe that XGP should be included in the differential diagnosis. (author)

  13. CT finding of cryptococcal meningitis

    We have experienced 14 cases of cryptococcal meningitis in the last 6 years. Their neurological signs, CT findings, and prognoses were studied. They fall into three types: the brain-stem-encephalitis type, the cortical-encephalitis type, and the meningitis type, according to the clinical course. The first type (6 cases) revealed mainly cerebellar signs, eye-movement damage, and so forth. The second type (5 cases) demonstrated ''Personality'' changes, chiefly aphasia. The third type (5 cases) did not show any focal signs. Prognosis of the brain-stem-encephalitis type was very poor, with a 50% mortality rate. In the survivors, also, clinical signs did not disappear for a long time. Repeated CT was performed in 13 among the 14 cases; abnormal CT findings were revealed in 5 cases because of cryptococcal infection. Granuloma shadow and ventriculitis shadow were observed in 3 cases each. These abnormal findings disappeared upon treatment except in one case. The clinical signs are not completely related with the CT finding, but it is useful that the site which has been infiltrated by the cryptococcus can be observed. Abnormal CT findings were observed in the 4 cases of the brain-stem-encephalitis type among the 5 abnormal cases. It is very useful to know the severity of the condition. (author)

  14. Ultrasonographic finding of trophoblastic disease

    Authors analysed ultrasonographic findings of 50 cases of trophoblastic diseases which were confirmed by D and E or hysterectomy. The following result was observed. 1. Among the 50 cases, 43 cases were hydatidiform moles and remainders were choriocarcionmas 2. Ultrasonographic findings of hydatidi form mole were as follows. a. The size of uterus was larger than that of expected one in 55 percent of cases and smaller than that in 9 percent. b. The vesicular pattern of internal echo could be found in all of the cases, and homogeneous echo pattern were observed in 32 cases(75 percent). c. secondary change, such as myometrial hemorrhage or necrosis, was shown in 33 cases (77 percent). d.In 34 cases (80 percent), sharply separable uterine wall from internal echo was demonstrated. e. In 8 cases(19 percent), ovarian theca-lutein cysts were observed. Among them, 5 cases contained bilateral cysts. All cysts had internal septation. 3. Ultrasonographic findings of choriocarcinomas showed similar findings of those of hydatidiform moles, but different findings from H-moles were more irregular vesicular pattern(4 cases: 57 percent) and inseparable vesicular pattern from uterine wall echo. 4. Correct diagnosis was made in 48 cases out of 50 and the diagnostic accuracy was 95 percent

  15. Pubic insufficiency fracture: MRI findings

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

  16. MR findings of cerebral palsy

    Yoon, Sang Hum; Chang, Seung Kuk; Cho, Mee Young; Park, Dong Woo; Kim, Jong Deok; Eun, Choong Ki [Pusan Paik Hospital, Pusan (Korea, Republic of)

    1994-11-15

    To evaluate the MR findings of brain damage in cerebral palised patients and to correlate it with gestational age and the time of damage. A retrospective analysis was performed in 40 patients who underwent MR scanning for evaluation of brain lesion in clinically diagnosed cerebral palsy. Authors classified the patients into two groups as premature and full-term and compared MR findings of the two groups. Abnormal MR findings were noted in 28 cases (70%). Five out of 6 patients who had been born prematurely showed isolate periventricular white matter lesions. Twenty-three out of 34 patients who had been born at full-term showed abnormal MR findings. Of these 23 patients, migration anomalies in 7 patients, isolate periventricular white matter lesions in 3 patients, and other combined periventricular subcortical white matter and deep gray matter lesions in 14 patients were seen. At least, 10 patients(43%) of full term group showed abnormal MRI findings reflecting intrauterine brain damage and all 5 patients of premature group showed isolate periventricular white matter lesions suggesting immaturity of brain. MRI is thought to be very useful in the assessment of brain damage for the patients with cerebral palsy by recognizing the location of the lesion and estimating the time of damage.

  17. Pubic insufficiency fracture: MRI findings

    Min, Tae Kyu; Lee, Yeon Soo; Park, Jeong Mi; Kim, Jee Young; Chung, Hong Jun; Lee, Eun Hee; Lee, Eun Ja; Kang, So Won [College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of); Han Tae Il [Eulji Medical College, Taejon (Korea, Republic of)

    2000-10-01

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

  18. MR findings of cerebral palsy

    To evaluate the MR findings of brain damage in cerebral palised patients and to correlate it with gestational age and the time of damage. A retrospective analysis was performed in 40 patients who underwent MR scanning for evaluation of brain lesion in clinically diagnosed cerebral palsy. Authors classified the patients into two groups as premature and full-term and compared MR findings of the two groups. Abnormal MR findings were noted in 28 cases (70%). Five out of 6 patients who had been born prematurely showed isolate periventricular white matter lesions. Twenty-three out of 34 patients who had been born at full-term showed abnormal MR findings. Of these 23 patients, migration anomalies in 7 patients, isolate periventricular white matter lesions in 3 patients, and other combined periventricular subcortical white matter and deep gray matter lesions in 14 patients were seen. At least, 10 patients(43%) of full term group showed abnormal MRI findings reflecting intrauterine brain damage and all 5 patients of premature group showed isolate periventricular white matter lesions suggesting immaturity of brain. MRI is thought to be very useful in the assessment of brain damage for the patients with cerebral palsy by recognizing the location of the lesion and estimating the time of damage

  19. Radiologic findings of neonatal sepsis

    To review the simple radiographic and sonographic findings in infants with neonatal sepsis. We retrospectively analyzed simple chest and abdominal radiographs, and brain sonograms in 36 newborn infants (preterm : term=23 :13). With neonatal sepsis diagnosed by blood culture and clinical manifestations. Pulmonary parenchymal infiltrate excluding respiratory distress syndrome and pulmonary edema or atelectasis was found in 22 infants (61%). Paralytic ileus, hepatosplenomegaly, and necrotizing enterocolitis were present in 18(50%), 9(25%), and 1(3%) infants, respectively, while skeletal changes suggesting osteomyelitis were found in three. Brain sonography was performed in 29 infants and in four, abnormalities were seen ; these comprised three germinal matrix hemorrhages and one intraparenchymal hemorrhage. In six patients(17%) radiologic examinations revealed no abnormality. In patients with neonatal sepsis, pulmonary infiltrates and paralytic ileus were common abnormalities. Although these were nonspecific, radiologic findings may be used to supplement clinical and laboratory findings in diagnosing neonatal sepsis and planning its treatment

  20. Imaging findings of avalanche victims

    Grosse, Alexandra B.; Grosse, Claudia A.; Anderson, Suzanne [University Hospital of Berne, Inselspital, Department of Diagnostic, Pediatric and Interventional Radiology, Berne (Switzerland); Steinbach, Lynne S. [University of California San Francisco, Department of Radiology, San Francisco, CA (United States); Zimmermann, Heinz [University Hospital of Berne, Inselspital, Department of Trauma and Emergency Medicine, Berne (Switzerland)

    2007-06-15

    Skiing and hiking outside the boundaries remains an attractive wilderness activity despite the danger of avalanches. Avalanches occur on a relatively frequent basis and may be devastating. Musculoskeletal radiologists should be acquainted with these injuries. Fourteen avalanche victims (11 men and 3 women; age range 17-59 years, mean age 37.4 years) were air transported to a high-grade trauma centre over a period of 2 years. Radiographs, CT and MR images were prospectively evaluated by two observers in consensus. Musculoskeletal findings (61%) were more frequent than extraskeletal findings (39%). Fractures were most commonly seen (36.6%), involving the spine (14.6%) more frequently than the extremities (9.8%). Blunt abdominal and thoracic trauma were the most frequent extraskeletal findings. A wide spectrum of injuries can be found in avalanche victims, ranging from extremity fractures to massive polytrauma. Asphyxia remains the main cause of death along with hypoxic brain injury and hypothermia. (orig.)

  1. US findings of breast sparganosis

    Kim, Yoon Soo; Hwang, Mi Soo; Lee, Jae Kyo; Kim, Dong Sug [Yeungnam University College of Medicine, Taegu (Korea, Republic of); Lee, Sang Kwnon [Dr. Lee' s Radiologic clinic, Taegu (Korea, Republic of)

    2003-09-15

    To evaluate the ultrasonographic appearances of breast sparganosis. We retrospectively reviewed ultrasonographic findings of five patients (mean age = 53 years) with pathologically proven breast sparganosis The shape, location, and surrounding boundary echo were evaluated. In addition, mammographic findings and clinical signs were also included. All patients presented with palpable masses. On ultrasonogram, all cases showed hypoechoic tubular mass and increased surrounding fat echo were observed. Four cases showed heterogeneous internal echo. Lesions were located in the subcutaneous fat layer in four cases and glandular tissue in one case. Three cases were located in the upper outer quadrant, and two cases, in the lower inner quadrant. Mammograms showed tubular increased density in two cases. Hypoechoic tubular mass with internal heterogeneous echo and increased surrounding fat echo in the subcutaneous fat layer can be the reliable ultrasonographic findings of breast sparganosis.

  2. US findings of breast sparganosis

    To evaluate the ultrasonographic appearances of breast sparganosis. We retrospectively reviewed ultrasonographic findings of five patients (mean age = 53 years) with pathologically proven breast sparganosis The shape, location, and surrounding boundary echo were evaluated. In addition, mammographic findings and clinical signs were also included. All patients presented with palpable masses. On ultrasonogram, all cases showed hypoechoic tubular mass and increased surrounding fat echo were observed. Four cases showed heterogeneous internal echo. Lesions were located in the subcutaneous fat layer in four cases and glandular tissue in one case. Three cases were located in the upper outer quadrant, and two cases, in the lower inner quadrant. Mammograms showed tubular increased density in two cases. Hypoechoic tubular mass with internal heterogeneous echo and increased surrounding fat echo in the subcutaneous fat layer can be the reliable ultrasonographic findings of breast sparganosis.

  3. Radiologic findings of neonatal sepsis

    Kim, Sam Soo; Han, Dae Hee; Choi, Guk Myeong; Jung, Hye Won [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of); Yoon, Hye Kyung; Han, Bokyung Kim; Lee, Nam Yong [Sansung Medical Center, Seoul (Korea, Republic of)

    1997-06-01

    To review the simple radiographic and sonographic findings in infants with neonatal sepsis. We retrospectively analyzed simple chest and abdominal radiographs, and brain sonograms in 36 newborn infants (preterm : term=23 :13). With neonatal sepsis diagnosed by blood culture and clinical manifestations. Pulmonary parenchymal infiltrate excluding respiratory distress syndrome and pulmonary edema or atelectasis was found in 22 infants (61%). Paralytic ileus, hepatosplenomegaly, and necrotizing enterocolitis were present in 18(50%), 9(25%), and 1(3%) infants, respectively, while skeletal changes suggesting osteomyelitis were found in three. Brain sonography was performed in 29 infants and in four, abnormalities were seen ; these comprised three germinal matrix hemorrhages and one intraparenchymal hemorrhage. In six patients(17%) radiologic examinations revealed no abnormality. In patients with neonatal sepsis, pulmonary infiltrates and paralytic ileus were common abnormalities. Although these were nonspecific, radiologic findings may be used to supplement clinical and laboratory findings in diagnosing neonatal sepsis and planning its treatment.

  4. CT findings of the thymus

    Kang, Eun Young; Kim, Yun Hwan; Seol, Hae Young; Chung, Woun Kyun; Suh, Won Hyuck [Korea University College of Medicine, Seoul (Korea, Republic of)

    1987-02-15

    In 14 cases of normal and abnormal thymus proved surgically and histopathologically in korea University Hae Wha Hospital during recent 6 years, the clinical and CT findings were analyzed. 1. Of 14 cases, 2 cases were normal thymus, 5 cases were thymic hyperplasia, 4 cases were benign thymoma, 2 case were malignant thymoma and 1 case was thymic cyst. 2. Of 14 cases, 10 cases were associated with myasthenia gravis, and 7 of these 10 cases were 3rd to 5th decades females. Among 10 cases with myasthenia gravis. 5 cases were thymic hyperplasia, 1 case was benign thymoma, 2 cases were malignant thymoma, and 2 cases were normal thymus. 3. All 5 thymic hyperplasia were associated with myasthenia gravis. CT findings of thymic hyperplasia were normal in 4 cases and increased lobe thickness in 1 case. 4. Of 4 cases of benign thymoma, only 1 case was associated with myasthenia gravis, and all 4 cases were positive findings in CT scan. CT findings of benign thymoma were round or oval soft tissue mass in anterior mediastinum, and 1 case had punctuate calcifications. 5. Of 2 cases of malignant thymoma, all 2 cases were associated with myasthenia gravis and positive findings in CT scan. CT findings of malignant thymoma were anterior mediastinal soft tissue mass with obliteration of the normal fat planes surrounding great vessels. SVC compression, and pleural tumor implants. 6. CT yielded significant diagnostic information of differential diagnosis between thymoma and thymoma hyperplasia in myasthenia gravis patients. Also CT was highly sensitive test in detection of thymoma and determined the extent and invasiveness of thymoma.

  5. CT findings of the thymus

    In 14 cases of normal and abnormal thymus proved surgically and histopathologically in korea University Hae Wha Hospital during recent 6 years, the clinical and CT findings were analyzed. 1. Of 14 cases, 2 cases were normal thymus, 5 cases were thymic hyperplasia, 4 cases were benign thymoma, 2 case were malignant thymoma and 1 case was thymic cyst. 2. Of 14 cases, 10 cases were associated with myasthenia gravis, and 7 of these 10 cases were 3rd to 5th decades females. Among 10 cases with myasthenia gravis. 5 cases were thymic hyperplasia, 1 case was benign thymoma, 2 cases were malignant thymoma, and 2 cases were normal thymus. 3. All 5 thymic hyperplasia were associated with myasthenia gravis. CT findings of thymic hyperplasia were normal in 4 cases and increased lobe thickness in 1 case. 4. Of 4 cases of benign thymoma, only 1 case was associated with myasthenia gravis, and all 4 cases were positive findings in CT scan. CT findings of benign thymoma were round or oval soft tissue mass in anterior mediastinum, and 1 case had punctuate calcifications. 5. Of 2 cases of malignant thymoma, all 2 cases were associated with myasthenia gravis and positive findings in CT scan. CT findings of malignant thymoma were anterior mediastinal soft tissue mass with obliteration of the normal fat planes surrounding great vessels. SVC compression, and pleural tumor implants. 6. CT yielded significant diagnostic information of differential diagnosis between thymoma and thymoma hyperplasia in myasthenia gravis patients. Also CT was highly sensitive test in detection of thymoma and determined the extent and invasiveness of thymoma.

  6. Radiologic findings of struma ovarii

    Kim, Jong Chul [Chungnam National Univ. School of Medicine, Taejeon (Korea, Republic of); Shin, Hyun Ja [Korea Veterans Hospital, Seoul (Korea, Republic of); Kim, Seung Hyup [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of); Byun, Jae Young [Catholic Univ. College of Medicine, Seoul (Korea, Republic of)

    1997-01-01

    Struma ovarii is ovarian tumor composed solely or predominantly of thyroid tissue or tumor in which hyperthyroidism results from ovarian thyroid tissue, and usually occurs in tandem with cystic teratoma. Ovarian cystic teratoma is radiologically easily diagnosed due to calcification or fat, for example, but the preoperative diagnosis of struma ovarii is often difficult due to rare characteristic features of thyroid tissue. Our purpose was to determine whether there were specific findings of struma ovarii which distinguished it from other ovarian tumors, and this involved analysis of its radiologic findings. Using ultrasonography, computed tomography, and magnetic resonance imaging, preoperative radiologic findings of pathologically-proven struma ovarii in eleven patients were retrospectively evaluated for site, margin, nature (cystic, solid, mixed), contrast enhancement, septa, mural nodule, calcification, fat, and metastasis. These findings were compared with pathologic findings. All eleven tumors were unilateral, ten had smooth tumor margins, seven were mixed cystic and solid tumors (more than 70% of solid components in one tumor), and nine had regular septa. Three of four cystic masses (one unilocular, one bilocular and two multilocular cysts) had mural nodules. Calcifications were found in two tumors, and fat in one. Malignant change or metastasis was not found in any tumor. In one patient with hyperthyroidism due to struma ovarii, symptoms and signs of this subsided after removal of the tumor on salpingo-oophorectomy. Most cases of struma ovarii occurred unilaterally within ovarian teratomas in premenopausal women, and were mixed cystic and solid masses with smooth margins that are commonly enhanced on contrast enhanced scans. In one patient, hyperthyroidism was caused by struma ovarii. There were, however, no specific radiologic findings that were sufficiently typical to suggest the correct preoperative diagnosis of struma ovarii.

  7. Associations between spondyloarthritis features and MRI findings

    Arnbak, Bodil; Jurik, Anne Grethe; Hørslev-Petersen, Kim;

    2015-01-01

    ASAS definition, was present in 217(21%) patients. Of those, 91(42%) had bone marrow oedema (BMO) at the minimum requirement according to ASAS (low BMO score). HLA-B27, peripheral arthritis, good response to NSAID, and preceding infection associated independently with SIJ MRI findings (OR range 1...... clinical features and MRI findings included in ASAS criteria, and 2) explore the associations between clinical features and MRI findings. METHODS: Patients aged 18-40 years with persistent LBP referred to an outpatient spine clinic were included. Information on clinical features (incl. HLA-B27 and CRP) and......OBJECTIVES: The Assessment of SpondyloArthritis international Society (ASAS) has previously published criteria for spondyloarthritis (SpA). The objectives in the current study were in a low back pain (LBP) cohort, including an unknown proportion of SpA patients, to: 1) estimate the prevalence of...

  8. MRI findings in the painful hemiplegic shoulder

    Aim: To evaluate the magnetic resonance imaging (MRI) findings in painful hemiplegic shoulder (PHS) in hemiplegic post-stroke patients. Materials and methods: Patients with hemiplegia following their first cerebrovascular accident who were admitted to the Sarah Network of Hospitals for Rehabilitation were studied. Forty-five patients with pain in the hemiplegic shoulder and 23 post-stroke patients without shoulder pain were investigated. MRI and radiographic findings of the hemiplegic and contralateral asymptomatic shoulders were evaluated. Results: Some MRI findings were more frequent in PHS group, including synovial capsule thickening, synovial capsule enhancement, and enhancement in the rotator cuff interval. Conclusions: Adhesive capsulitis was found to be a possible cause of PHS.

  9. MRI findings in the painful hemiplegic shoulder

    Tavora, D.G.F., E-mail: danielgurgel@sarah.b [Department of Radiology, Sarah Network of Hospitals for Rehabilitation, Fortaleza (Brazil); Gama, R.L.; Bomfim, R.C. [Department of Radiology, Sarah Network of Hospitals for Rehabilitation, Fortaleza (Brazil); Nakayama, M. [Department of Radiology, Federal University of Grande Dourados, Dourados (Brazil); Silva, C.E.P. [Department of Statistics, Sarah Network of Hospitals for Rehabilitation, Fortaleza (Brazil)

    2010-10-15

    Aim: To evaluate the magnetic resonance imaging (MRI) findings in painful hemiplegic shoulder (PHS) in hemiplegic post-stroke patients. Materials and methods: Patients with hemiplegia following their first cerebrovascular accident who were admitted to the Sarah Network of Hospitals for Rehabilitation were studied. Forty-five patients with pain in the hemiplegic shoulder and 23 post-stroke patients without shoulder pain were investigated. MRI and radiographic findings of the hemiplegic and contralateral asymptomatic shoulders were evaluated. Results: Some MRI findings were more frequent in PHS group, including synovial capsule thickening, synovial capsule enhancement, and enhancement in the rotator cuff interval. Conclusions: Adhesive capsulitis was found to be a possible cause of PHS.

  10. MR findings of chondromalacia Patella : correlation of the grade and associated lesions with arthroscopic findings

    Chung, Yon Su; Kwon, Soon Tae; Lee, Hwan Do; Kang, Yong Soo; Byun, Ki Yong; Rhee, Kwang Jin [Chungnam National Univ., Taejon (Korea, Republic of). Coll. of Medicine

    1998-02-01

    To assess the MR findings of chondromalacia patella and correlate the grade and associated lesions with the arthroscopic findings. Twenty-five patients with pain in the anterior part of the knee underwent fat-suppressed axial and coronal T2-weighted and T2-weighted imaging, using a 10-cm field of view, and a 5-inch general purpose coil. We retrospectively assessed these findings, and the locations, grades and associated lesions, and correlated these with arthroscopic findings. We evaluated the exact location and grade of chondromalacia patella and associated lesions, as seen on MR images. These and the arthroscopic findings showed close correlation, and in cases involving this condition, MRI is thus a useful indicator of an appropriate surgical method and plan. (author). 18 refs., 5 figs.

  11. Pott's disease: radioisotope scanning findings

    The study is aim was to describe findings in bone scan in patients with Pott's disease. Eight patients had a bone scan with 99mTc . The findings included: a spindle image due to increased uptake in vertebrae and intervertebral uptake in three cases, increased uptake in vertebrae in three cases, paravertebral uptake in one case and vertebral compression with diminished uptake in one case. Bone scan is a useful tool in evaluating spinal tuberculosis (Pott's disease) as an indicator of activity within the lesion. (authors)

  12. Fucosidosis: MRI and MRS findings

    Fucosidosis is a rare, autosomal recessive lysosomal storage disease in which fucose-containing glycolipids, glycoproteins, and oligosaccharides accumulate in tissues as a consequence of α-l-fucosidase enzyme deficiency. We present the MR imaging findings of diffuse white-matter hyperintensity and pallidal curvilinear streak hyperintensity in a 6-year-old Caucasian girl with a diagnosis of fucosidosis based on cDNA isolated from skin fibroblasts. This report also includes the MRS findings of a decreased N-acetylaspartate/choline ratio together with an abnormal peak at 3.8 ppm which expand the knowledge of the neuroradiological spectrum of this rare disease. (orig.)

  13. Fucosidosis: MRI and MRS findings

    Oner, Ali Y.; Akpek, Sergin [Gazi University School of Medicine, Department of Radiology, Ankara (Turkey); Cansu, Ali; Serdaroglu, Ayse [Gazi University School of Medicine, Department of Paediatrics, Ankara (Turkey)

    2007-10-15

    Fucosidosis is a rare, autosomal recessive lysosomal storage disease in which fucose-containing glycolipids, glycoproteins, and oligosaccharides accumulate in tissues as a consequence of {alpha}-l-fucosidase enzyme deficiency. We present the MR imaging findings of diffuse white-matter hyperintensity and pallidal curvilinear streak hyperintensity in a 6-year-old Caucasian girl with a diagnosis of fucosidosis based on cDNA isolated from skin fibroblasts. This report also includes the MRS findings of a decreased N-acetylaspartate/choline ratio together with an abnormal peak at 3.8 ppm which expand the knowledge of the neuroradiological spectrum of this rare disease. (orig.)

  14. Wiring systems and fault finding

    Scaddan, Brian

    1905-01-01

    This book deals with an area of practice which many students and non-electricians find particularly challenging. It explains how to interpret circuit diagrams, wiring systems and the principles and practice of testing and fault diagnosis. It will give the reader confidence to understand the principles of testing and to apply this knowledge to fault finding in electrical circuits.It is a handy reference for anybody who needs to be able to trace faults in circuits, whether in domestic, commercial or industrial settings. It will be a time-saver for all electricians, plumbers, heating engineers, t

  15. Comparison of preoperative neuroradiographic findings and surgical findings in lumbar disc herniation

    Takahara, Kazuhiro; Sera, Keisuke; Nakamura, Masakazu; Uchida, Takeshi [Nagasaki Mitsubishi Hospital (Japan); Ito, Nobuyuki

    1997-09-01

    Surgical findings in lumbar disc hernia were compared to pre-operative MRI, CTM and myelogram findings. Ninety-one cases were studied using Love`s method. The accuracy of hernia diagnosis in MRI was 59.3%, 41.2% in CTM, and 35.2% in myelogram. At the L5/S1 disc level, the accuracy of hernia diagnosis by CTM and myelogram was decreased. MRI was useful for the diagnosis and cure of lumbar disc herniation. (author)

  16. Comparison of preoperative neuroradiographic findings and surgical findings in lumbar disc herniation

    Surgical findings in lumbar disc hernia were compared to pre-operative MRI, CTM and myelogram findings. Ninety-one cases were studied using Love's method. The accuracy of hernia diagnosis in MRI was 59.3%, 41.2% in CTM, and 35.2% in myelogram. At the L5/S1 disc level, the accuracy of hernia diagnosis by CTM and myelogram was decreased. MRI was useful for the diagnosis and cure of lumbar disc herniation. (author)

  17. The Heritability of Eating Disorders: Methods and Current Findings

    Thornton, Laura M.; Mazzeo, Suzanne E.; Bulik, Cynthia M.

    2011-01-01

    Family, twin, and adoption studies of anorexia nervosa (AN), bulimia nervosa (BN), binge-eating disorder (BED), and the proposed purging disorder presentation (PD) have consistently demonstrated that genetic factors contribute to the variance in liability to eating disorders. In addition, endophenotypes and component phenotypes of eating disorders have been evaluated and provide further insight regarding genetic factors influencing eating disorders and eating disorder diagnostic criteria. Man...

  18. Finding the Most Distant Quasars Using Bayesian Selection Methods

    Mortlock, Daniel

    2014-01-01

    Quasars, the brightly glowing disks of material that can form around the super-massive black holes at the centres of large galaxies, are amongst the most luminous astronomical objects known and so can be seen at great distances. The most distant known quasars are seen as they were when the Universe was less than a billion years old (i.e., $\\sim\\!7%$ of its current age). Such distant quasars are, however, very rare, and so are difficult to distinguish from the billions of other comparably-bright sources in the night sky. In searching for the most distant quasars in a recent astronomical sky survey (the UKIRT Infrared Deep Sky Survey, UKIDSS), there were $\\sim\\!10^3$ apparently plausible candidates for each expected quasar, far too many to reobserve with other telescopes. The solution to this problem was to apply Bayesian model comparison, making models of the quasar population and the dominant contaminating population (Galactic stars) to utilise the information content in the survey measurements. The result wa...

  19. Sustainable Development Index in Hong Kong: Approach, Method and Findings

    Tso, Geoffrey K. F.; Yau, Kelvin K. W.; Yang, C. Y.

    2011-01-01

    Sustainable development is a priority area of research in many countries and regions nowadays. This paper illustrates how a multi-stakeholders engagement process can be applied to identify and prioritize the local community's concerns and issues regarding sustainable development in Hong Kong. Ten priority areas covering a wide range of community's…

  20. Behavioral Couples Therapy for Substance Abuse: Rationale, Methods, and Findings

    Fals-Stewart, William; O’Farrell, Timothy J.; Birchler, Gary R.

    2004-01-01

    Behavioral couples therapy (BCT), a treatment approach for married or cohabiting drug abusers and their partners, attempts to reduce substance abuse directly and through restructuring the dysfunctional couple interactions that frequently help sustain it. In multiple studies with diverse populations, patients who engage in BCT have consistently reported greater reductions in substance use than have patients who receive only individual counseling. Couples receiving BCT also have reported higher...