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Sample records for centroid finding method

  1. Centroid finding method for position-sensitive detectors

    International Nuclear Information System (INIS)

    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

    OpenAIRE

    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 ...

  3. Modified S2 and Pattern Search Methods to Find Optimal Cluster Centroid for Multi-Variable Functions

    Directory of Open Access Journals (Sweden)

    K. Reddy Madhavi,

    2012-04-01

    Full Text Available Identification of useful clusters in large datasets has attracted considerable interest in clustering process. Since data in the World Wide Web is increasing exponentially that affects on clustering accuracy and decision making, change in the concept between every cluster occurs named concept drift. To detect the difference of cluster distributions between the current data subset and previous clustering result, an algorithm called Drifting Concept Detection (DCD and proper data labeling need to be performed. To say that the data labeling was performed well, generated clusters must be efficient. Selecting initial cluster center (centroid is the key factor that has high affection in generating effective clusters. The data with different properties exists in real world. Previous work was concentrated in the identification of optimal cluster centroid for the functions of multi variables using Simplex Search (S2 method and Pattern Search using Modified Sectioning method. These methods are extended by providing modified S2 and pattern search methods that finds optimal cluster centroid for the multi variable functions and tests for optimality and then apply any existing clustering algorithm to generate clusters.

  4. High-position-resolution scintillation neutron-imaging detector by crossed-fiber readout with novel centroid-finding method

    CERN Document Server

    Katagiri, M; Sakasai, K; Matsubayashi, M; Birumachi, A; Takahashi, H; Nakazawa, M

    2002-01-01

    Aiming at high-position-resolution and high-counting-rate neutron imaging, a novel centroid-finding method is proposed for a scintillation neutron-imaging detector with crossed-fiber readout. Crossed wavelength-shifting fibers are arranged on and under the scintillator. Luminescences generated in the scintillator are emitted and detected by a few fibers surrounding the incident point of a neutron. In the novel method, X and Y positions of the incident neutron are decided by coincidence of a central signal and neighboring signals, respectively. By fundamental experiments using a ZnS:Ag/ sup 6 LiF scintillator of 0.5-mm thickness and crossed wavelength-shifting fibers with a size of 0.5 x 0.5 mm sup 2 , it was confirmed that the position resolution is about 0.5 mm and the limitation of the neutron-counting rate is 320 kcps. (orig.)

  5. An Integrated Centroid Finding and Particle Overlap Decomposition Algorithm for Stereo Imaging Velocimetry

    Science.gov (United States)

    McDowell, Mark

    2004-01-01

    An integrated algorithm for decomposing overlapping particle images (multi-particle objects) along with determining each object s constituent particle centroid(s) has been developed using image analysis techniques. The centroid finding algorithm uses a modified eight-direction search method for finding the perimeter of any enclosed object. The centroid is calculated using the intensity-weighted center of mass of the object. The overlap decomposition algorithm further analyzes the object data and breaks it down into its constituent particle centroid(s). This is accomplished with an artificial neural network, feature based technique and provides an efficient way of decomposing overlapping particles. Combining the centroid finding and overlap decomposition routines into a single algorithm allows us to accurately predict the error associated with finding the centroid(s) of particles in our experiments. This algorithm has been tested using real, simulated, and synthetic data and the results are presented and discussed.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

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

    Scientific Electronic Library Online (English)

    Moysés, Nascimento; Cosme Damião, Cruz; Ana Carolina Mota, Campana; Rafael Simões, Tomaz; Caio Césio, Salgado; Reinaldo de Paula, Ferreira.

    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 in english 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 test the method. The genotypes underwent 20 cuts, from November 2004 to June 2006. Each cut was considered an environment. The inclusion of ideotypes of greater biological average production in the environments produced an arrow-shaped graphical dispersion directed to the right in which the most productive genotypes were placed near the tip of the arrow. With the alteration only five genotypes were classified into the former classes of the original centroid method. The arrow-shaped figure allowed a direct comparison of genotypes throughout the productivity gradient. The alteration performed in the method preserved the easy interpretation of results for genotype recommendations of the original method, and does leaves no room for ambiguity in interpretation of the results.

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

    Directory of Open Access Journals (Sweden)

    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 test the method. The genotypes underwent 20 cuts, from November 2004 to June 2006. Each cut was considered an environment. The inclusion of ideotypes of greater biological average production in the environments produced an arrow-shaped graphical dispersion directed to the right in which the most productive genotypes were placed near the tip of the arrow. With the alteration only five genotypes were classified into the former classes of the original centroid method. The arrow-shaped figure allowed a direct comparison of genotypes throughout the productivity gradient. The alteration performed in the method preserved the easy interpretation of results for genotype recommendations of the original method, and does leaves no room for ambiguity in interpretation of the results.

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

    International Nuclear Information System (INIS)

    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(?,3n)99Ru reaction, in which an isomeric state in 99Ru was found. (Auth.)

  11. A further investigation of the centroid-to-centroid method for stereotactic lung radiotherapy: A phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Bo; Samant, Sanjiv; Mittauer, Kathryn; Lee, Soyoung; Huang, Yin; Li, Jonathan; Kahler, Darren; Liu, Chihray [Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, Florida 32610 (United States)

    2013-10-15

    Purpose: Our previous study [B. Lu et al., “A patient alignment solution for lung SBRT setups based on a deformable registration technique,” Med. Phys. 39(12), 7379–7389 (2012)] proposed a deformable-registration-based patient setup strategy called the centroid-to-centroid (CTC) method, which can perform an accurate alignment of internal-target-volume (ITV) centroids between averaged four-dimensional computed tomography and cone-beam computed tomography (CBCT) images. Scenarios with variations between CBCT and simulation CT caused by irregular breathing and/or tumor change were not specifically considered in the patient study [B. Lu et al., “A patient alignment solution for lung SBRT setups based on a deformable registration technique,” Med. Phys. 39(12), 7379–7389 (2012)] due to the lack of both a sufficiently large patient data sample and a method of tumor tracking. The aim of this study is to thoroughly investigate and compare the impacts of breathing pattern and tumor change on both the CTC and the translation-only (T-only) gray-value mode strategies by employing a four-dimensional (4D) lung phantom.Methods: A sophisticated anthropomorphic 4D phantom (CIRS Dynamic Thorax Phantom model 008) was employed to simulate all desired respiratory variations. The variation scenarios were classified into four groups: inspiration to expiration ratio (IE ratio) change, tumor trajectory change, tumor position change, tumor size change, and the combination of these changes. For each category the authors designed several scenarios to demonstrate the effects of different levels of breathing variation on both of the T-only and the CTC methods. Each scenario utilized 4DCT and CBCT scans. The ITV centroid alignment discrepancies for CTC and T-only were evaluated. The dose-volume-histograms (DVHs) of ITVs for two extreme cases were analyzed.Results: Except for some extreme cases in the combined group, the accuracy of the CTC registration was about 2 mm for all cases for both the single and the combined scenarios. The performance of the CTC method was insensitive to region-of-registration (ROR) size selections, as suggested by the comparable accuracy between 1 and 2 cm expansions of the ROR selections for the method. The T-only method was suitable for some single scenarios, such as trajectory variation, position variation, and size variation. However, for combined scenarios and/or a large variation in the IE ratio, the T-only method failed to produce reasonable registration results (within 3 mm). The discrepancy was close to, or even greater than, 1 cm. In addition, unlike the CTC method, the T-only method was sensitive to the ROR size selection. The DVH analysis suggested that a large ITV to PTV margin should be considered if a breathing pattern variation is observed.Conclusions: The phantom study demonstrated that the CTC method was reliable for scenarios in which breathing pattern variation was involved. The T-only gray value method worked for some scenarios, but not for scenarios that involved an IE ratio variation. For scenarios involving position variation, the T-only method worked only with a careful selection of the ROR, whereas the CTC method was independent of ROR size as long as the ITVs were included in the ROR. One indication of the dose consequence analysis was that a large ITV to PTV margin should be considered if a breathing pattern variation is observed.

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

    International Nuclear Information System (INIS)

    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, ?sub(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 ?sub(p) by a factor of 1/?k. It also shows that ?sub(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)

  13. Shack-Hartmann centroid detection method based on high dynamic range imaging and normalization techniques

    OpenAIRE

    Quiroga Mellado, Juan Antonio; Vargas, Javier; González Fernández, Luis M.; Belenguer Dávila, Tomás

    2010-01-01

    In the optical quality measuring process of an optical system, including diamond-turning components, the use of a laser light source can produce an undesirable speckle effect in a Shack-Hartmann (SH) CCD sensor. This speckle noise can deteriorate the precision and accuracy of the wavefront sensor measurement. Here we present a SH centroid detection method founded on computer-based techniques and capable of measurement in the presence of strong speckle noise. The method extends the dynamic ran...

  14. Multiple centroid method to evaluate the adaptability of alfalfa genotypes / Metodologia dos centroides múltiplos para avaliação da adaptabilidade em genótipos de alfafa

    Scientific Electronic Library Online (English)

    Moysés, Nascimento; Adésio, Ferreira; Ana Carolina Campana, Nascimento; Fabyano Fonseca e, Silva; Reinaldo de Paula, Ferreira; Cosme Damião, Cruz.

    2015-02-01

    Full Text Available Este trabalho teve como objetivo avaliar a eficiência do método dos centroides múltiplos em um estudo de adaptabilidade de genótipos de alfafa (Medicago sativa L.). Neste método os genótipos são comparados a ideótipos definidos de acordo com o interesse do pesquisador por meio do modelo de regressão [...] bissegmentada. Desta forma a classificação dos genótipos é realizada conforme objetivo do pesquisador e a estratégia de recomendação desejada. Apesar do grande potencial do método há a necessidade que o mesmo seja avaliado sob o aspecto biológico (com dados reais). Assim, diante deste contexto foram utilizados dados provenientes de um experimento em blocos casualizados com 2 repetições, que constituiu-se da avaliação da produção de matéria seca de 92 cultivares de alfafa em 20 cortes, realizados no período de novembro de 2004 a junho de 2006. A metodologia dos Centroides Múltiplos mostrou-se eficiente na classificação de genótipos de alfafa. Além de não apresentar duplicidade de indicações e proporcionar que ideótipos fossem definidos de acordo com o interesse do pesquisador facilitando a interpretação dos dados. Abstract in english 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 classi [...] fication 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.

  15. The Gibbs Centroid Sampler

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, William A.; Newberg, Lee A.; Conlan, Sean; McCue, Lee Ann; Lawrence, Charles E.

    2007-07-01

    The Gibbs Centroid Sampler is a software package designed for locating conserved elements in biopolymer sequences. The Gibbs Centroid Sampler reports a centroid alignment, i.e., an alignment that has the minimum total distance to the set of samples chosen from the a posteriori probability distribution of transcription factor binding site alignments. In so doing, it garners information from the full ensemble of solutions, rather than only the single most probable point that is the target of many motif finding algorithms, including its predecessor, the Gibbs Recursive Sampler. Centroid estimators have been shown to yield substantial improvements, in both sensitivity and positive predictive values, to the prediction of RNA secondary structure and motif finding. The Gibbs Centroid Sampler, along with interactive tutorials, an online user manual, and information on downloading the software, is available at http://bayesweb.wadsworth.org/gibbs/gibbs.html.

  16. The Gibbs Centroid Sampler.

    Science.gov (United States)

    Thompson, William A; Newberg, Lee A; Conlan, Sean; McCue, Lee Ann; Lawrence, Charles E

    2007-07-01

    The Gibbs Centroid Sampler is a software package designed for locating conserved elements in biopolymer sequences. The Gibbs Centroid Sampler reports a centroid alignment, i.e. an alignment that has the minimum total distance to the set of samples chosen from the a posteriori probability distribution of transcription factor binding-site alignments. In so doing, it garners information from the full ensemble of solutions, rather than only the single most probable point that is the target of many motif-finding algorithms, including its predecessor, the Gibbs Recursive Sampler. Centroid estimators have been shown to yield substantial improvements, in both sensitivity and positive predictive values, to the prediction of RNA secondary structure and motif finding. The Gibbs Centroid Sampler, along with interactive tutorials, an online user manual, and information on downloading the software, is available at: http://bayesweb.wadsworth.org/gibbs/gibbs.html. PMID:17483517

  17. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    OpenAIRE

    Xue-tao Yu; Xiao-ping Rui; Feng Li

    2013-01-01

    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 tr...

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

    International Nuclear Information System (INIS)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    International Nuclear Information System (INIS)

    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. (Auth.)

  2. Measurement Precision and Accuracy of the Centre Location of AN Ellipse by Weighted Centroid Method

    Science.gov (United States)

    Matsuoka, R.

    2015-03-01

    Circular targets are often utilized in photogrammetry, and a circle on a plane is projected as an ellipse onto an oblique image. This paper reports an analysis conducted in order to investigate the measurement precision and accuracy of the centre location of an ellipse on a digital image by an intensity-weighted centroid method. An ellipse with a semi-major axis a, a semi-minor axis b, and a rotation angle ? of the major axis is investigated. In the study an equivalent radius r = (a2cos2? + b2sin2?)1/2 is adopted as a measure of the dimension of an ellipse. First an analytical expression representing a measurement error (ϵx, ϵy,) is obtained. Then variances Vx of ϵx are obtained at 1/256 pixel intervals from 0.5 to 100 pixels in r by numerical integration, because a formula representing Vx is unable to be obtained analytically when r > 0.5. The results of the numerical integration indicate that Vxwould oscillate in a 0.5 pixel cycle in r and Vx excluding the oscillation component would be inversely proportional to the cube of r. Finally an effective approximate formula of Vx from 0.5 to 100 pixels in r is obtained by least squares adjustment. The obtained formula is a fractional expression of which numerator is a fifth-degree polynomial of {r-0.5×int(2r)} expressing the oscillation component and denominator is the cube of r. Here int(x) is the function to return the integer part of the value x. Coefficients of the fifth-degree polynomial of the numerator can be expressed by a quadratic polynomial of {0.5×int(2r)+0.25}.

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

    Directory of Open Access Journals (Sweden)

    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.

  4. Selection of Initial Centroids for k-Means Algorithm?

    OpenAIRE

    Anand M. Baswade; Prakash S. Nalwade?

    2013-01-01

    Clustering is one of the important data mining techniques. k-Means [1] is one of the mostimportant algorithm for Clustering. Traditional k-Means algorithm selects initial centroids randomly and ink-Means algorithm result of clustering highly depends on selection of initial centroids. k-Means algorithm issensitive to initial centroids so proper selection of initial centroids is necessary. This paper introduces anefficient method to start the k-Means with good initial centroids. Good initial ce...

  5. The Gibbs Centroid Sampler

    OpenAIRE

    Thompson, William A.; Newberg, Lee A; Conlan, Sean; McCue, Lee Ann; LAWRENCE, CHARLES E.

    2007-01-01

    The Gibbs Centroid Sampler is a software package designed for locating conserved elements in biopolymer sequences. The Gibbs Centroid Sampler reports a centroid alignment, i.e. an alignment that has the minimum total distance to the set of samples chosen from the a posteriori probability distribution of transcription factor binding-site alignments. In so doing, it garners information from the full ensemble of solutions, rather than only the single most probable point that is the target of man...

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

    Directory of Open Access Journals (Sweden)

    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.

  7. Geogebra: Calculation of Centroid

    Directory of Open Access Journals (Sweden)

    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. Centroid Based Text Clustering

    Directory of Open Access Journals (Sweden)

    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.

  9. A Robust Front-End Processor combining Mel Frequency Cepstral Coefficient and Sub-band Spectral Centroid Histogram methods for Automatic Speech Recognition

    Directory of Open Access Journals (Sweden)

    R. Thangarajan

    2009-06-01

    Full Text Available Environmental robustness is an important area of research in speech recognition. Mismatch between trained speech models and actual speech to be recognized is due to factors like background noise. It can cause severe degradation in the accuracy of recognizers whichare based on commonly used features like mel-frequency cepstral co-efficient (MFCC and linear predictive coding (LPC. It is well understood that all previous auditory based feature extraction methods perform extremely well in terms of robustness due to the dominantfrequency information present in them. But these methods suffer from high computational cost. Another method called sub-band spectral centroid histograms (SSCH integrates dominant-frequency information with sub-band power information. This method is based onsub-band spectral centroids (SSC which are closely related to spectral peaks for both clean and noisy speech. Since SSC can be computed efficiently from short-term speech power spectrum estimate, SSCH method is quite robust to background additive noise at a lowercomputational cost. It has been noted that MFCC method outperforms SSCH method in the case of clean speech. However in the case of speech with additive noise, MFCC method degrades substantially. In this paper, both MFCC and SSCH feature extraction have beenimplemented in Carnegie Melon University (CMU Sphinx 4.0 and trained and tested on AN4 database for clean and noisy speech. Finally, a robust speech recognizer which automatically employs either MFCC or SSCH feature extraction methods based on the variance of shortterm power of the input utterance is suggested.

  10. The generalized centroid difference method for picosecond sensitive determination of lifetimes of nuclear excited states using large fast-timing arrays

    Energy Technology Data Exchange (ETDEWEB)

    Régis, J.-M., E-mail: regis@ikp.uni-koeln.de [Institut für Kernphysik der Universität zu Köln, Zülpicher Str. 77, 50937 Köln (Germany); Mach, H. [Departamento de Física Atómica y Nuclear, Universidad Complutense, 28040 Madrid (Spain); Simpson, G.S. [Laboratoire de Physique Subatomique et de Cosmologie Grenoble, 53, rue des Martyrs, 38026 Grenoble Cedex (France); Jolie, J.; Pascovici, G.; Saed-Samii, N.; Warr, N. [Institut für Kernphysik der Universität zu Köln, Zülpicher Str. 77, 50937 Köln (Germany); Bruce, A. [School of Computing, Engineering and Mathematics, University of Brighton, Lewes Road, Brighton BN2 4GJ (United Kingdom); Degenkolb, J. [Institut für Kernphysik der Universität zu Köln, Zülpicher Str. 77, 50937 Köln (Germany); Fraile, L.M. [Departamento de Física Atómica y Nuclear, Universidad Complutense, 28040 Madrid (Spain); Fransen, C. [Institut für Kernphysik der Universität zu Köln, Zülpicher Str. 77, 50937 Köln (Germany); Ghita, D.G. [Horia Hulubei National Institute for Physics and Nuclear Engineering, 77125 Bucharest (Romania); and others

    2013-10-21

    A novel method for direct electronic “fast-timing” lifetime measurements of nuclear excited states via ?–? coincidences using an array equipped with N?N equally shaped very fast high-resolution LaBr{sub 3}(Ce) scintillator detectors is presented. Analogous to the mirror symmetric centroid difference method, the generalized centroid difference method provides two independent “start” and “stop” time spectra obtained by a superposition of the N(N?1)?–? 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 ?–? cascade. Provided that the energy response and the electronic time pick-off of the detectors are almost equal, a mean prompt response difference between start and stop events is calibrated and used as a single correction for lifetime determination. These combined fast-timing arrays mean ?–? time-walk characteristics can be determined for 40keVmethod over the total dynamic range is mainly determined by the statistics. The setup of an N=4 detector fast-timing array delivered an absolute time resolving power of 3 ps for 10 000 ?–? events per total fast timing array start and stop time spectrum. The new method is tested over the total dynamic range by the measurements of known picosecond lifetimes in standard ?-ray sources.

  11. Noise in position measurement by centroid calculation

    International Nuclear Information System (INIS)

    The position of a particle trajectory in a gaseous (or semiconductor) detector can be measured by calculating the centroid of the induced charge on the cathode plane. The charge amplifiers attached to each cathode strip introduce noise which is added to the signal. This noise broadens the position resolution line. Our article gives an analytical tool to estimate the resolution broadening due to the noise per strip and the number of strips involved in the centroid calculation. It is shown that the position resolution increases faster than the square root of the number of strips involved. We also consider the consequence of added interstrip capacitors, intended to diminish the differential nonlinearity. It is shown that the position error increases slower than linearly with the interstrip capacities, due to the cancellation of correlated noise. The estimation we give, can be applied to calculations of position broadening other than the centroid finding. (orig.)

  12. Evidence for subduction beneath Gibraltar Arc and Andean regions from k-means earthquake centroids

    Science.gov (United States)

    Ramdani, Faiçal; Kettani, Omar; Tadili, Benaissa

    2015-01-01

    k-Means algorithms are widely used for determining clusters in broad types of datasets. Since zones of high seismic activity as plate boundary present diffuse seismicity patterns, the use of k-algorithm is a way to classify earthquakes in terms of centroids. Mapping centroids improves seismic visibility for further tectonic interpretation. We used selected datasets of earthquakes and determined the number of clusters or values of k by introducing the silhouette index method to check the validity of cluster numbers. By introducing magnitude size in the vectorial attributes, k-means algorithm provides a map of centroids that represents the location of high seismic energy, which is useful in seismic risk assessment. By including the depth of seismic events as the main attribute, we obtained spatiotemporal variations of centroids, which improve the image resolution of seismicity at depth to find out the underlying dynamic process. This has been achieved in subduction zone of Chile where the presence of slab is reflected by centroid distribution. The method is particularly relevant to complex seismic zones where controversial geodynamic models are reported such as the Gibraltar Arc. Resulting model supports W-oriented subduction underlying many parts of the Gibraltar zone.

  13. Centroid Bodies and the Logarithmic Laplace Transform - A Unified Approach

    CERN Document Server

    Klartag, Bo'az

    2011-01-01

    We unify and slightly improve several bounds on the isotropic constant of high-dimensional convex bodies; in particular, a linear dependence on the body's psi-2 constant is obtained. Along the way, we present some new bounds on the volume of L_p-centroid bodies and yet another equivalent formulation of Bourgain's hyperplane conjecture. Our method is a combination of the L_p-centroid body technique of Paouris and the logarithmic Laplace transform technique of the first named author.

  14. STATISTICS OF CENTROIDS OF VELOCITY

    Directory of Open Access Journals (Sweden)

    A. Esquivel

    2009-01-01

    Full Text Available We review the use of velocity centroids statistics to recover information of interstellar turbulence from observations. Velocity centroids have been used for a long time now to retrieve information about the scaling properties of the turbulent velocity field in the interstellar medium. We show that, while they are useful to study subsonic turbulence, they do not trace the statistics of velocity in supersonic turbulence, because they are highly influenced by fluctuations of density. We show also that for sub-Alfvénic turbulence (both supersonic and subsonic two-point statistics (e.g. correlation functions or power-spectra are anisotropic. This anisotropy can be used to determine the direction of the mean magnetic field projected in the plane of the sky.

  15. Orbit extension method for finding unstable orbits

    International Nuclear Information System (INIS)

    The orbit extension method is a technique for building long orbits from shorter ones. Combined with Newton's method, it gives a powerful and efficient tool for finding various orbits of area-preserving twist maps on a cylinder. It is particularly valuable for unstable orbits. This method is developed and used to find two kinds of orbits: ordered periodic orbits and principal heteroclinic orbits between two resonances. Flux from one resonance to another is obtained as a by-product of the principal heteroclinic orbits

  16. Intelligent systems for analyzing soccer games: The weighted centroid / Sistemas Inteligentes para el análisis de fútbol: centroide ponderado

    Scientific Electronic Library Online (English)

    F, Clemente; M, Santos-Couceiro; F, Lourenço-Martins; R, Sousa; A, Figueiredo.

    2014-12-01

    Full Text Available Nuevos sistemas inteligentes se han desarrollado recientemente, con el fin de mejorar la calidad de análisis del partido. Estos sistemas basan su análisis en el comportamiento táctico de los equipos, sin embargo, todos los métodos innovadores necesitan algunos cambios para aumentar su potencial en l [...] as implicaciones prácticas. Por lo tanto, el objetivo principal de este trabajo es proponer una actualización del centroide y métrica del equipo, teniendo en cuenta a todos los jugadores del equipo y también la posición de la bola, además, tiene como objetivo analizar la relación entre los centroides de los equipos oponentes. Un partido de fútbol 11, fue analizado con el fin de aplicar el nuevo algoritmo del centroide; los principales resultados mostraron una fuerte evidencia de la relación positiva entre centroides en el eje x (r s = 0.781) y el eje y (r s = 0.0707). Este estudio, confirma trabajos previos que analizaron la relación positiva y fuerte entre equipos centroides. Además, fue posible demostrar la pertinencia de la nueva actualización de métrica táctica y su importancia para el aumento de la información en las aplicaciones prácticas durante el partido. Abstract in english New, intelligent systems have been developed recently to improve the quality of match analysis. These systems analyze the tactical behavior of the teams. However, the existing methods leave room for improvement. Thus, the main goal of this study is to refine the team centroid metric by considering a [...] ll of the players on the team and the ball position. Furthermore, this study analyzes the relationship between the centroids of the two opposing teams. One 11-on-11 soccer match was analyzed to test the new centroid algorithm. The results provided strong evidence of the positive relation between the centroids of the two teams over time in the x-axis (r s = 0.781) and the y-axis (r s = 0.0707). This study confirmed the results of previous studies that analyzed the relationship between team centroids. Furthermore, it was possible to prove the effectiveness of the new tactical metric and its relevance for adding information during a match.

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

    International Nuclear Information System (INIS)

    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

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

    CERN Document Server

    Hele, Timothy J H; 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 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.

  19. FINGERPRINT MATCHING BASED ON PORE CENTROIDS

    Directory of Open Access Journals (Sweden)

    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. Full Sky Astrometric Mapping Explorer, FAME, CCD Centroiding Experiment

    Science.gov (United States)

    Triebes, K.; Gilliam, L.; Harris, F.; Hilby, T.; Horner, S.; Monet, D.; Perkins, P.; Vassar, R.

    1999-12-01

    FAME is a MIDEX astrometry experiment designed to map the positions of 40,000,000 stars to an accuracy of 50 micro-arc seconds. Optimized between mission requirements, size, weight, and cost, the FAME instrument consists of a 0.6 x 0.25 m2 aperture whose point spread function central peak is linearly sampled by two pixels. In order to achieve its astrometric mapping mission requirements, this instrument must achieve a single look centroiding accuracy on a visual magnitude 9.0 star of yielding unexpected dividends in refining CCD operations and centroid data analysis. This poster paper describes the experiment design, centroiding results, CCD operating techniques and data analysis methods. This work was jointly sponsored by Lockheed Martin and the U.S. Naval Observatory.

  1. GPU-Assisted Computation of Centroidal Voronoi Tessellation

    OpenAIRE

    Rong, Guodong; Liu, Yang; WANG, WENPING; Yin, Xaotian; Gu, Xianfeng; Guo, Xiaohu

    2011-01-01

    Centroidal Voronoi tessellations (CVT) are widely used in computational science and engineering. The most commonly used method is Lloyd's method, and recently the L-BFGS method is shown to be faster than Lloyd's method for computing the CVT. However, these methods run on the CPU and are still too slow for many practical applications. We present techniques to implement these methods on the GPU for computing the CVT on 2D planes and on surfaces, and demonstrate significant speedup of these GPU-...

  2. Maser Source Finding Methods in HOPS

    CERN Document Server

    Walsh, Andrew J; Longmore, Steven; Jordan, Christopher H; Lowe, Vicki

    2011-01-01

    The {\\bf H}$_2${\\bf O} Southern Galactic {\\bf P}lane {\\bf S}urvey (HOPS) has observed 100 square degrees of the Galactic plane, using the Mopra radio telescope to search for emission from multiple spectral lines in the 12\\,mm band (19.5\\,--\\,27.5\\,GHz). Perhaps the most important of these spectral lines is the 22.2\\,GHz water maser transition. We describe the methods used to identify water maser candidates and subsequent confirmation of the sources. Our methods involve a simple determination of likely candidates by searching peak emission maps, utilising the intrinsic nature of water maser emission - spatially unresolved and spectrally narrow-lined. We estimate completeness limits and compare our method with results from the {\\sc Duchamp} source finder. We find that the two methods perform similarly. We conclude that the similarity in performance is due to the intrinsic limitation of the noise characteristics of the data. The advantages of our method are that it is slightly more efficient in eliminating spuri...

  3. Estimating the Doppler centroid of SAR data

    DEFF Research Database (Denmark)

    Madsen, SØren NØrvang

    1989-01-01

    After reviewing frequency-domain techniques for estimating the Doppler centroid of synthetic-aperture radar (SAR) data, the author describes a time-domain method and highlights its advantages. In particular, a nonlinear time-domain algorithm called the sign-Doppler estimator (SDE) is shown to have attractive properties. An evaluation based on an existing SEASAT processor is reported. The time-domain algorithms are shown to be extremely efficient with respect to requirements on calculations and memory, and hence they are well suited to real-time systems where the Doppler estimation is based on raw SAR data. For offline processors where the Doppler estimation is performed on processed data, which removes the problem of partial coverage of bright targets, the ?E estimator and the CDE (correlation Doppler estimator) algorithm give similar performance. However, for nonhomogeneous scenes it is found that the nonlinear SDE algorithm, which estimates the Doppler-shift on the basis of data signs alone, gives superior performance

  4. Maser Source Finding Methods in HOPS

    OpenAIRE

    Andrew J. Walsh; Purcell, Cormac; Longmore, Steven; Jordan, Christopher H.; Lowe, Vicki

    2011-01-01

    The {\\bf H}$_2${\\bf O} Southern Galactic {\\bf P}lane {\\bf S}urvey (HOPS) has observed 100 square degrees of the Galactic plane, using the Mopra radio telescope to search for emission from multiple spectral lines in the 12\\,mm band (19.5\\,--\\,27.5\\,GHz). Perhaps the most important of these spectral lines is the 22.2\\,GHz water maser transition. We describe the methods used to identify water maser candidates and subsequent confirmation of the sources. Our methods involve a sim...

  5. Improving the Initial Centroids of k-means Clustering Algorithm to Generalize its Applicability

    Science.gov (United States)

    Goyal, M.; Kumar, S.

    2014-12-01

    k-means is one of the most widely used partition based clustering algorithm. But the initial centroids generated randomly by the k-means algorithm cause the algorithm to converge at the local optimum. So to make k-means algorithm globally optimum, the initial centroids must be selected carefully rather than randomly. Though many researchers have already been carried out for the enhancement of k-means algorithm, they have their own limitations. In this paper a new method to formulate the initial centroids is proposed which results in better clusters equally for uniform and non-uniform data sets.

  6. An Automatic Method of Finding Topic Boundaries

    OpenAIRE

    Reynar, Jeffrey C.

    1994-01-01

    This article outlines a new method of locating discourse boundaries based on lexical cohesion and a graphical technique called dotplotting. The application of dotplotting to discourse segmentation can be performed either manually, by examining a graph, or automatically, using an optimization algorithm. The results of two experiments involving automatically locating boundaries between a series of concatenated documents are presented. Areas of application and future directions...

  7. Determination of Star Bodies from -Centroid Bodies

    Indian Academy of Sciences (India)

    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 $\\Gamma_p\\langle K \\rangle$ characterized by having larger volume than any other member, for all real $p \\geq 1$ that are not even natural numbers, where $\\Gamma_p\\langle K \\rangle$ denotes the -centroid equivalence class of the star body .

  8. Numerical Methods for Finding Stationary Gravitational Solutions

    CERN Document Server

    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.

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

    CERN Document Server

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

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

    International Nuclear Information System (INIS)

    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.)

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

    OpenAIRE

    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.

  13. Centroid Velocity Statistics of Molecular Clouds

    CERN Document Server

    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...

  14. Centroid velocity statistics of molecular clouds

    Science.gov (United States)

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

    2015-02-01

    We compute structure functions and Fourier spectra of 2D centroid velocity maps in order to study the gas dynamics of typical molecular clouds 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 n0 = 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 CVISF and Fourier spectra for H2 are significantly steeper than those for the different CO tracers, independent of the density and the numerical resolution. This is due to the larger space-filling factor of H2 as it is better able to self-shield in diffuse regions, leading to a larger fractal co-dimension compared to CO.

  15. The Schrödinger formulation of the Feynman path centroid density

    CERN Document Server

    Ramírez, R; Ram\\'irez, Rafael; López-Ciudad, Telesforo

    1999-01-01

    We present an analysis of the Feynman path centroid density that provides new insight into the correspondence between the path integral and the Schrödinger formulations of statistical mechanics. The path centroid density is a central concept for several approximations (centroid molecular dynamics, quantum transition state theory, and pure quantum self-consistent harmonic approximation) that are used in path integral studies of thermodynamic and dynamical properties of quantum particles. The centroid density is related to the quasi-static response of the equilibrium system to an external force. The path centroid dispersion is the canonical correlation of the position operator, that measures the linear change in the mean position of a quantum particle upon the application of a constant external force. At low temperatures, this quantity provides an approximation to the excitation energy of the quantum system. In the zero temperature limit, the particle's probability density obtained by fixed centroid path integ...

  16. Accurate Alignment of Plasma Channels Based on Laser Centroid Oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Gonsalves, Anthony; Nakamura, Kei; Lin, Chen; Osterhoff, Jens; Shiraishi, Satomi; Schroeder, Carl; Geddes, Cameron; Toth, Csaba; Esarey, Eric; Leemans, Wim

    2011-03-23

    A technique has been developed to accurately align a laser beam through a plasma channel by minimizing the shift in laser centroid and angle at the channel outptut. If only the shift in centroid or angle is measured, then accurate alignment is provided by minimizing laser centroid motion at the channel exit as the channel properties are scanned. The improvement in alignment accuracy provided by this technique is important for minimizing electron beam pointing errors in laser plasma accelerators.

  17. A New Method for Finding Vacua in String Phenomenology

    CERN Document Server

    Gray, J; Ilderton, A; Lukas, A; Gray, James; He, Yang-Hui; Ilderton, Anton; Lukas, Andre

    2007-01-01

    One of the central problems of string-phenomenology is to find stable vacua in the four dimensional effective theories which result from compactification. We present an algorithmic method to find all of the vacua of any given string-phenomenological system in a huge class. In particular, this paper reviews and then extends hep-th/0606122 to include various non-perturbative effects. These include gaugino condensation and instantonic contributions to the superpotential.

  18. Rapid determinations of centroid moment tensor in Turkey

    Science.gov (United States)

    Nakano, Masaru; Citak, Seckin; Kalafat, Dogan

    2015-04-01

    Rapid determination of centroid moment tensor (CMT) of earthquakes, namely the source centroid location, focal mechanism, and magnitude is important for early disaster responses and issuing Tsunami warnings. Using the SWIFT system (Source parameter determinations based on Waveform Inversion of Fourier Transformed seismograms) developed by Nakano et al. (2008), we are developing earthquake monitoring system in Turkey. Also determinations of CMT for background seismicity can resolve the stress field in the crust, which may contribute to evaluate potential earthquake, to develop scenarios for future disastrous earthquakes, or to find hidden faults in the crust. Using data from regional network in Turkey, we have tried a waveform inversion for an M=4.4 earthquake that occurred about 50 km south of Sea of Marmara, of which source location is at 40.0N and 27.9E with 15 km depth (after the ANSS Comprehensive Catalog). We successfully obtained the CMT solution showing a right-lateral strike-slip fault, of which one of the nodal planes strikes ENE-WSW, corresponding to the strike of an active fault mapped here. This fault runs parallel to the north Anatolian fault, and large earthquakes of Ms 7.2 and 7.0 ruptured this fault on 1953 and 1964, respectively. Using the regional network data, we can determine CMT for earthquakes as small as magnitude about 4. Of course, the lower limit of magnitude depend on the data quality. In the research project of SATREPS - Earthquake and tsunami disaster mitigation in the Marmara region and disaster education in Turkey, we will develop CMT determination system and CMT catalogue in Turkey.

  19. Optimization of the autocorrelation weighting function for the time-domain calculation of spectral centroids.

    Science.gov (United States)

    Heo, Seo; Hur, Don; Kim, Hyungsuk

    2015-03-01

    Spectral centroid from the backscattered ultrasound provides important information about the attenuation properties of soft tissues and Doppler effects of blood flows. Because the spectral centroid is originally determined from the power spectrum of backscattered ultrasound signals in the frequency domain, it is natural to calculate it after converting time-domain signals into spectral domain signals, using the fast Fourier transform (FFT). Recent research, however, derived the time-domain equations for calculating the spectral centroid using a Parseval's theorem, to avoid the calculation of the Fourier transform. The work only presented the final result, which showed that the computational time of the proposed time-domain method was 4.4 times faster than that of the original FFT-based method, whereas the average estimation error was negligible. In this paper, we present the optimal design of the autocorrelation weighting function, which is used for the timedomain spectral centroid estimation process, to reduce the computational time significantly. We also carry out a comprehensive analysis of the computational complexities of the FFTbased and time-domain methods with respect to the length of ultrasound signal segments. The simulation results using numerical phantoms show that, with the optimized autocorrelation weighting function, we only need approximately 3% of the full set of data points. In addition to that, because the proposed optimization technique requires a fixed number of data points to calculate the spectral centroid, the execution time is constant as the length of the data segment increases, whereas the execution time of the conventional FFT-based method is increased. Analysis of the computational complexities between the proposed method and the conventional FFT-based method presents O(N) and O(Nlog2N), respectively. PMID:25768811

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

    CERN Document Server

    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...

  1. A Doubly Nudged Elastic Band Method for Finding Transition States

    CERN Document Server

    Trygubenko, S A; Trygubenko, Semen A.; Wales, David J.

    2004-01-01

    A modification of the nudged elastic band (NEB) method is presented that enables stable optimisations to be run using both the limited-memory quasi-Newton (L-BFGS) and slow-response quenched velocity Verlet (SQVV) minimisers. The performance of this new `doubly nudged' DNEB method is analysed in conjunction with both minimisers and compared with previous NEB formulations. We find that the fastest DNEB approach (DNEB/L-BFGS) can be quicker by up to two orders of magnitude. Applications to permutational rearrangements of the seven-atom Lennard-Jones cluster (LJ7) and highly cooperative rearrangements of LJ38 and LJ75 are presented. We also outline an updated algorithm for constructing complicated multi-step pathways using successive DNEB runs.

  2. Gridded Population of the World, Version 3 (GPWv3): Centroids

    Data.gov (United States)

    National Aeronautics and Space Administration — Gridded Population of the World, Version 3 (GPWv3) Centroids consists of estimates of human population counts and densities for the years 1990, 1995, 2000, 2005,...

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

    Directory of Open Access Journals (Sweden)

    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.

  4. Finding and characterising WHIM structures using the luminosity density method

    CERN Document Server

    Nevalainen, J; Tempel, E; Branchini, E; Roncarelli, M; Giocoli, C; Heinamaki, P; Saar, E; Bonamente, M; Einasto, M; Finoguenov, A; Kaastra, J; Lindfors, E; Nurmi, P; Ueda, Y

    2014-01-01

    We have developed a new method to approach the missing baryons problem. We assume that the missing baryons reside in a form of Warm Hot Intergalactic Medium, i.e. the WHIM. Our method consists of (a) detecting the coherent large scale structure in the spatial distribution of galaxies that traces the Cosmic Web and that in hydrodynamical simulations is associated to the WHIM, (b) map its luminosity into a galaxy luminosity density field, (c) use numerical simulations to relate the luminosity density to the density of the WHIM, (d) apply this relation to real data to trace the WHIM using the observed galaxy luminosities in the Sloan Digital Sky Survey and 2dF redshift surveys. In our application we find evidence for the WHIM along the line of sight to the Sculptor Wall, at redshifts consistent with the recently reported X-ray absorption line detections. Our indirect WHIM detection technique complements the standard method based on the detection of characteristic X-ray absorption lines, showing that the galaxy l...

  5. Automatic segmentation and centroid detection of skin sensors for lung interventions

    Science.gov (United States)

    Lu, Kongkuo; Xu, Sheng; Xue, Zhong; Wong, Stephen T.

    2012-02-01

    Electromagnetic (EM) tracking has been recognized as a valuable tool for locating the interventional devices in procedures such as lung and liver biopsy or ablation. The advantage of this technology is its real-time connection to the 3D volumetric roadmap, i.e. CT, of a patient's anatomy while the intervention is performed. EM-based guidance requires tracking of the tip of the interventional device, transforming the location of the device onto pre-operative CT images, and superimposing the device in the 3D images to assist physicians to complete the procedure more effectively. A key requirement of this data integration is to find automatically the mapping between EM and CT coordinate systems. Thus, skin fiducial sensors are attached to patients before acquiring the pre-operative CTs. Then, those sensors can be recognized in both CT and EM coordinate systems and used calculate the transformation matrix. In this paper, to enable the EM-based navigation workflow and reduce procedural preparation time, an automatic fiducial detection method is proposed to obtain the centroids of the sensors from the pre-operative CT. The approach has been applied to 13 rabbit datasets derived from an animal study and eight human images from an observation study. The numerical results show that it is a reliable and efficient method for use in EM-guided application.

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

    International Nuclear Information System (INIS)

    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

  7. A Centroid Model for the Depth Assessment of Images using Rough Fuzzy Set Techniques

    Directory of Open Access Journals (Sweden)

    P. Swarnalatha

    2012-04-01

    Full Text Available Detection of affected areas in images is a crucial step in assessing the depth of the affected area for municipal operators. These affected areas in the underground images, which are line images are indicative of the condition of buried infrastructures like sewers and water mains. These images identify affected areas and extract their properties like structures from the images, whose contrast has been enhanced... A Centroid Model for the Depth Assessment of Images using Rough Fuzzy Set Techniques presents a three step method which is a simple, robust and efficient one to detect affected areas in the underground concrete images. The proposed methodology is to use segmentation and feature extraction using structural elements. The main objective for using this model is to find the dimensions of the affected areas such as the length, width, depth and the type of the defects/affected areas. Although human eye is extremely effective at recognition and classification, it is not suitable for assessing defects in images, which might have spread over thousands of miles of image lines. The reasons are mainly fatigue, subjectivity and cost. Our objective is to reduce the effort and the labour of a person in detecting the affected areas in underground images. A proposal to apply rough fuzzy set theory to compute the lower and upper approximations of the affected area of the image is made in this paper. In this connection we propose to use some concepts and technology developed by Pal and Maji.

  8. Plasma Channel Diagnostic Based on Laser Centroid Oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Gonsalves, Anthony; Nakamura, Kei; Lin, Chen; Osterhoff, Jens; Shiraishi, Satomi; Schroeder, Carl; Geddes, Cameron; Toth, Csaba; Esarey, Eric; Leemans, Wim

    2010-09-09

    A technique has been developed for measuring the properties of discharge-based plasma channels by monitoring the centroid location of a laser beam exiting the channel as a function of input alignment offset between the laser and the channel. The centroid position of low-intensity (<10{sup 14}Wcm{sup -2}) laser pulses focused at the input of a hydrogen-filled capillary discharge waveguide was scanned and the exit positions recorded to determine the channel shape and depth with an accuracy of a few %. In addition, accurate alignment of the laser beam through the plasma channel can be provided by minimizing laser centroid motion at the channel exit as the channel depth is scanned either by scanning the plasma density or the discharge timing. The improvement in alignment accuracy provided by this technique will be crucial for minimizing electron beam pointing errors in laser plasma accelerators.

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

    CERN Document Server

    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 ...

  10. First experimental results of very high accuracy centroiding measurements for the neat astrometric mission

    CERN Document Server

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

    2013-01-01

    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. In this paper we present the metrology and the pseudo stellar sources sub-systems, we present a performance model and an error budget of the experiment and we report the present status of the demonstration. Finally we also pres...

  11. An Accurate and Efficient Gaussian Fit Centroiding Algorithm for Star Trackers

    Science.gov (United States)

    Delabie, Tjorven; Schutter, Joris De; Vandenbussche, Bart

    2015-06-01

    This paper presents a novel centroiding algorithm for star trackers. The proposed algorithm, which is referred to as the Gaussian Grid algorithm, fits an elliptical Gaussian function to the measured pixel data and derives explicit expressions to determine the centroids of the stars. In tests, the algorithm proved to yield accuracy comparable to that of the most accurate existing algorithms, while being significantly less computationally intensive. Hence, the Gaussian Grid algorithm can deliver high centroiding accuracy to spacecraft with limited computational power. Furthermore, a hybrid algorithm is proposed in which the Gaussian Grid algorithm yields an accurate initial estimate for a least squares fitting method, resulting in a reduced number of iterations and hence reduced computational cost. The low computational cost allows to improve performance by acquiring the attitude estimates at a higher rate or use more stars in the estimation algorithms. It is also a valuable contribution to the expanding field of small satellites, where it could enable low-cost platforms to have highly accurate attitude estimation.

  12. Asymptotic behavior of the centroids of a family of vortices

    Science.gov (United States)

    Emamizadeh, B.; Mehrabi, M. H.

    2003-09-01

    In this article we consider a family of minimization problems whose solutions represent the vortices of two dimensional flows. We prove that if we consider an admissible sequence of vortices, then the corresponding centroids converge to the global minimizer of the Routh function associated with an appropriate energy functional.

  13. Class hierarchy method to find Change-Proneness

    OpenAIRE

    Malan V.Gaikwad; Aparna S.Nakil,; Akhil Khare,

    2011-01-01

    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 ide...

  14. Finding function: evaluation methods for functional genomic data

    Directory of Open Access Journals (Sweden)

    Barrett Daniel R

    2006-07-01

    Full Text Available Abstract Background Accurate evaluation of the quality of genomic or proteomic data and computational methods is vital to our ability to use them for formulating novel biological hypotheses and directing further experiments. There is currently no standard approach to evaluation in functional genomics. Our analysis of existing approaches shows that they are inconsistent and contain substantial functional biases that render the resulting evaluations misleading both quantitatively and qualitatively. These problems make it essentially impossible to compare computational methods or large-scale experimental datasets and also result in conclusions that generalize poorly in most biological applications. Results We reveal issues with current evaluation methods here and suggest new approaches to evaluation that facilitate accurate and representative characterization of genomic methods and data. Specifically, we describe a functional genomics gold standard based on curation by expert biologists and demonstrate its use as an effective means of evaluation of genomic approaches. Our evaluation framework and gold standard are freely available to the community through our website. Conclusion Proper methods for evaluating genomic data and computational approaches will determine how much we, as a community, are able to learn from the wealth of available data. We propose one possible solution to this problem here but emphasize that this topic warrants broader community discussion.

  15. Class hierarchy method to find Change-Proneness

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

    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...

  17. General Method for Finding the Most Economical Distributed Router Architecture

    OpenAIRE

    Kencl, Lukas; Radunovic, Bozidar

    2002-01-01

    In this work we present a novel method to determine the optimal parameters of a router architecture when certain router performance constraints are given. The total financial expense, or cost, is the optimality criterion. We introduce a general, essentially distributed, router architecture model, consisting of locally or remotely located forwarding engines or processing units gathered around a switch of variable speed. Given the following constraints: number of inputs, maximum line interface ...

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

    Energy Technology Data Exchange (ETDEWEB)

    Patton, H.J. [Geophysics Group, Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico (United States)

    1998-11-01

    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 (M{sub 0}) 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 {plus_minus}13 km and {plus_minus}17{degree}, respectively. On the other hand, M{sub 0} estimates are found to be biased, with CMT M{sub 0} larger than regional estimates by an average of 0.27{plus_minus}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 M{sub 0} estimates. I suggest that causes for M{sub 0} 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. M{sub 0}:m{sub b} scaling relationships for central Asian earthquakes show better agreement with western U.S. scaling when M{sub 0} estimates determined in this study are used. {copyright} 1998 American Geophysical Union

  19. Centroid Detection by Gaussian Pattern Matching in Adaptive Optics

    CERN Document Server

    Vyas, Akondi; Prasad, B Raghavendra

    2009-01-01

    Shack Hartmann wavefront sensor is a two dimensional array of lenslets which is used to detect the incoming phase distorted wavefront through local tilt measurements made by recording the spot pattern near the focal plane. Wavefront reconstruction is performed in two stages - (a) image centroiding to calculate local slopes, (b) formation of the wavefront shape from local slope measurement. Centroiding accuracy contributes to most of the wavefront reconstruction error in Shack Hartmann sensor based adaptive optics system with readout and background noise. It becomes even more difficult in atmospheric adaptive optics case, where scintillation effects may also occur. In this paper we used a denoising technique based on thresholded Zernike reconstructor to minimize the effects due to readout and background noise. At low signal to noise ratio, this denoising technique can be improved further by taking the advantage of the shape of the spot. Assuming a Gaussian pattern for individual spots, it is shown that the cen...

  20. Non-obtuse Remeshing with Centroidal Voronoi Tessellation

    KAUST Repository

    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.

  1. The RPC space resolution with the charge centroid method

    International Nuclear Information System (INIS)

    RPC detectors were originally developed to exploit the very good intrinsic time resolution of the plane geometry and have been used as muon trigger in most of their high energy physics applications, disregarding the detector space resolution. Due to the high luminosity of future colliders, new experiments will be very demanding in terms of momentum selection of the muon spectrometer. For this reason, trigger detectors will be required to have a sub-millimeter space resolution as well as a sub-nanosecond time resolution. RPCs are good candidates for these applications, as it can be shown that they have excellent intrinsic space resolution, while the actual results depend mostly on the front-end electronics performance. Here we present a beam test carried out on a small size RPC. The results are consistent with a space resolution of ? 130 ?m

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

    Directory of Open Access Journals (Sweden)

    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.

  3. Gravimetric method to find internal surface of macroporous silicon membranes

    Energy Technology Data Exchange (ETDEWEB)

    Nechitailov, A.A.; Astrova, E.V.; Kukushkina, Yu.A. [Ioffe Physico-Technical Institute, Russian Academy of Sciences, St. Petersburg 194021 (Russian Federation)

    2007-07-01

    A simple method to evaluate the internal surface area, porosity, pore diameter and pore density of macroporous silicon membranes has been proposed and tested. The porosity p is obtained from the mass loss under anodizing, and the surface area per unit volume S{sub v} is determined from the mass of SiO{sub 2} formed on the pore surface as a result of thermal oxidation. The average pore diameter d and pore density N can be easily calculated from the obtained S{sub v} and p. Experimental verification of d and N was performed by means of SEM and optical microscope images; S{sub v} was checked by BET technique. Surface area and porosity on the resistivity of initial n-Si in the range {rho}=3-25 Ohm.cm have been studied for the samples with regular and self-organized macropore ''lattices''. The obtained values are within the limits p=27-50%, S{sub v}=2800-6000 cm{sup 2}/cm{sup 3}, d=1.9-6.5 {mu}m, N=1.4-10 x 10{sup 6} cm{sup -2}, and in a good agreement with the data of microscopic characterization. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  4. Scintillation-induced jitter of projected light with centroid trackers.

    Science.gov (United States)

    Holmes, Richard B

    2009-02-01

    When light radiating from a distant object passes through extended turbulence, the light is scintillated. Such scintillated light may be received by an optical system and passed to a camera in the focal plane, and used to track an object. Such trackers often use centroid trackers. Then a laser or other light may be projected back toward the object, steered by the centroid measured on the tracker. The presence of scintillation on the tracker return will cause a jitter error in the pointing of projected light, if the projected light's intensity differs from that of the incoming scintillation pattern. This error is caused by a lack of full-field conjugation of the tilt component of the received return. This error is considered, for horizontal path conditions, as a difference between centroid tilt and gradient tilt. The estimated error is typically not large, and is estimated by both simulation and analytic means, and these are found to agree for conditions of interest. The possibility of means for correction of this error is discussed briefly. PMID:19183683

  5. Plasma Channel Diagnostic Based on Laser Centroid Oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Gonsalves, A.J.; Nakamura, K.; Lin, C.; Osterhoff, J.; Shiraishi, S.; Schroeder, C.B.; Geddes, C.G.R.; Toth, Cs.; Esarey, E.; Leemans, W.P.

    2010-02-12

    A technique has been developed for measuring the properties of discharge-based plasma channels by monitoring the centroid location of a laser beam exiting the channel as a function of input alignment offset between the laser and the channel. Experiments were performed using low-intensity (< 1014 Wcm-2) laser pulses focused onto the entrance of a hydrogen-filled capillary discharge waveguide. Scanning the laser centroid position at the input of the channel and recording the exit position allows determination of the channel depth with an accuracy of a few percent, measurement of the transverse channel shape, and inference of the matched spot size. In addition, accurate alignment of the laser beam through the plasma channel is provided by minimizing laser centroid motion at the channel exit as the channel depth is scanned either by scanning the plasma density or the discharge timing. The improvement in alignment accuracy provided by this technique will be crucial for minimizing electron beam pointing errors in laser plasma accelerators.

  6. Improved envelope and centroid equations for high current beams

    International Nuclear Information System (INIS)

    The standard envelope equation for charged particle beams (e.g., Lee-Cooper) neglects self-field contributions from the beam rotation and the slope of the beam envelope. We have carried out an expansion that includes these effects to first order, resulting in a new equation for the edge radius. The change in beam kinetic energy due to space-charge depression as the beam radius varies is also included. For the centroid equation, we have included the 'self-steering' effect due to the curvature of the beam orbit. To leading order, there is a cancellation between the self-steering effect and the space-charge depression of the beam energy, so that a more accurate centroid equation is obtained by using the undepressed value of the energy (i.e., the total beam energy) to calculate the orbit. We have implemented the envelope and centroid equations in the Lamda code. The effect of the new terms will be illustrated with calculations for the DARHT accelerators at the Los Alamos National Laboratory

  7. Automated Centroid-based False Positive Detection of Kepler Planet Candidates

    Science.gov (United States)

    Mullally, Fergal; The Kepler Team

    2015-08-01

    We present a new technique to automate the identification of false positive planet candidates in Kepler data due to background eclipsing binaries. Background events from resolved or partially resolved sources can be identified by shifts in the distribution of light across CCD pixels during transit that produce shifts in the measured centroid of the stellar image. False positive signals are identified using this technique in all Kepler planet candidate catalogs, however the method was automated for this first time in the Q1-Q16 catalog of Mullally et al (2015). We describe the technique, its strengths and weaknesses.

  8. Novas abordagens da avaliação do comportamento tático no futebol: análise do centroid e índice de dispersão / Towards a new evaluation of the football' tactical behaviour: analysis of the centroid and stretch index

    Scientific Electronic Library Online (English)

    Rui Manuel, Mendes; Filipe Manuel, Clemente; Micael Santos, Couceiro; Fernando Manuel Lourenço, Martins.

    2013-12-01

    Full Text Available A tendência evolutiva do futebol determina as necessidades de produzir ferramentas inovadoras que aumentem substancialmente a eficiência da análise de jogo. Considerando os métodos tradicionais notacionais como limitados para a interpretação dos processos de jogo, a investigação carece de novos méto [...] dos nos quais prevaleça a análise do processo. Dessa forma, o presente trabalho propõe-se a analisar novas métricas quantitativas e automáticas de avaliação tática no futebol, nomeadamente o centroid de equipe e o índice de dispersão. Abstract in english The evolutionary tendency of the football game determines the conception of the new tools that increase the efficiency of the match analysis. The traditional notational analysis, actually, are limited to understand the true dynamic of the football match, thus the investigation lacks by new methods t [...] o understand the process and not just the product. Therefore, this work aims analyze new automatically tactical metrics, specifically the centroid and the stretch index method.

  9. Methods for Synthesizing Findings on Moderation Effects Across Multiple Randomized Trials

    OpenAIRE

    Brown, C Hendricks; Sloboda, Zili; FAGGIANO, Fabrizio; Teasdale, Brent; Keller, Ferdinand; Burkhart, Gregor; Vigna-Taglianti, Federica; Howe, George; Masyn, Katherine; Wang, Wei; Muthén, Bengt; Stephens, Peggy; Grey, Scott; Perrino, Tatiana

    2013-01-01

    This paper presents new methods for synthesizing results from subgroup and moderation analyses across different randomized trials. We demonstrate that such a synthesis generally results in additional power to detect significant moderation findings above what one would find in a single trial. Three general methods for conducting synthesis analyses are discussed, with two methods, integrative data analysis, and parallel analyses, sharing a large advantage over traditional methods available in m...

  10. An Efficient Range Partitioning Method for Finding Frequent Patterns from Huge Database

    Directory of Open Access Journals (Sweden)

    Ms. Ruchita Gupta

    2012-06-01

    Full Text Available Data mining is finding increasing acceptance inscience and business areas that need to analyzelarge amounts of data to discover trends that theycould not otherwise find. Different applications mayrequire different data mining techniques. The kindsof knowledge that could be discovered from adatabase are categorized into association rulesmining, sequential patterns mining, classification,and clustering. In this paper we present an efficientrange partitioning method for finding frequentpattern from huge database. It is based on key baseddivision for finding the local frequent pattern(LFP. After finding the partition frequent patternfrom the subdivided local database, we then find theglobal frequent pattern from the local database andperform the pruning from the whole database.

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

    Directory of Open Access Journals (Sweden)

    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. Finding-equal regression method and its application in predication of U resources

    International Nuclear Information System (INIS)

    The commonly adopted deposit model method in mineral resources predication has two main part: one is model data that show up geological mineralization law for deposit, the other is statistics predication method that accords with characters of the data namely pretty regression method. This kind of regression method may be called finding-equal regression, which is made of the linear regression and distribution finding-equal method. Because distribution finding-equal method is a data pretreatment which accords with advanced mathematical precondition for the linear regression namely equal distribution theory, and this kind of data pretreatment is possible of realization. Therefore finding-equal regression not only can overcome nonlinear limitations, that are commonly occurred in traditional linear regression or other regression and always have no solution, but also can distinguish outliers and eliminate its weak influence, which would usually appeared when Robust regression possesses outlier in independent variables. Thus this newly finding-equal regression stands the best status in all kind of regression methods. Finally, two good examples of U resource quantitative predication are provided

  13. Centroid offset estimation in the Fourier domain for a highly sensitive Shack–Hartmann wavefront sensor

    International Nuclear Information System (INIS)

    The estimation of the centroid offset can have an effect on the accuracy of wavefront measurements conducted by highly sensitive Shack–Hartmann wavefront sensors. In this paper, a novel offset estimation algorithm processed in the Fourier domain is proposed. This method can be used to process the offset estimation in the Fourier domain and is efficient in noise suppression. The principle of the algorithm is described in detail. Comparisons between the technique and two other widely used algorithms, the best-threshold center of gravity algorithm and the correlation algorithm, are performed theoretically using numerical simulation and experimentally using a Shack–Hartmann wavefront sensor. The results show that the proposed offset estimation algorithm is unbiased, as robust as the correlation algorithm, as fast as the best-threshold center of gravity algorithm, and achieves a good balance between precision and speed. (paper)

  14. Franck–Condon factors and r-centroids for the diatomic fluorides of germanium and silicon

    Directory of Open Access Journals (Sweden)

    S. KANAGAPRABHA

    2008-05-01

    Full Text Available A suitable potential energy function was found by analysing the potential functions proposed by Morse, Mohammad and Rafi et al. for the A2?+–X2?3/2 and B2?+–X2?3/2 band systems of GeF and the 1?–1? band system of SiF. It was found that the potential proposed by Rafi et al. is in close agreement with the Rydberg–Klein–Rees (R–K–R potential. Using this potential, the wave functions were evaluated by the Wentzel–Kramer–Brillouin (W–K–B method. The Franck–Condon factors and r-centroids were computed by a numerical integration technique. The results are compared with available theoretical values. The intensities of the various bands were investigated.

  15. Efficient Search and Fit Methods to Find Nerve Stimulation Parameters for Multi-Contact Electrodes

    Science.gov (United States)

    Freeberg, Max J; Schiefer, Matthew A.; Triolo, Ronald J.

    2015-01-01

    This paper describes a method to efficiently sample EMG recruitment space over a wide range of pulse amplitude (PA) and pulse width (PW). A gradient based search method is developed to find high information areas of a recruitment surface. This search method is first examined in the context of simulated EMG recruitment data and its ability to sample and subsequently fit Gompertz-Function-inspired surfaces to it. The search method is then used to determine parameters when stimulating through an 8 contact flat interface nerve electrode (FINE). The recorded EMG recruitment data are then used to validate the Gompertz surface fitting method as well as the search method. PMID:22256009

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

    CERN Document Server

    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...

  17. An Efficient Range Partitioning Method for Finding Frequent Patterns from Huge Database

    Directory of Open Access Journals (Sweden)

    Ruchita Gupta

    2012-06-01

    Full Text Available Data mining is finding increasing acceptance in science and business areas that need to analyze large amounts of data to discover trends that they could not otherwise find. Different applications may require different data mining techniques. The kinds of knowledge that could be discovered from a database are categorized into association rules mining, sequential patterns mining, classification, and clustering. In this paper we present an efficient range partitioning method for finding frequent pattern from huge database. It is based on key based division for finding the local frequent pattern (LFP. After finding the partition frequent pattern from the subdivided local database, we then find the global frequent pattern from the local database and perform the pruning from the whole database.

  18. A new method to find full complex roots of a complex dispersion equation for light propagation

    CERN Document Server

    Wan, Li

    2011-01-01

    A new numerical method is presented to find full complex roots of a complex dispersion equation. For the application of the solution, the complex dispersion equation of a cylindrical metallic nanowire is investigated. By using this method, locus of Brewster angle, complex dispersion curves of Surface Plasmon Polaritons (SPPs) and complex bulk modes can be obtained in once calculation. Approximate analytical solution to the complex dispersion equation has also been derived to verify our method.

  19. Expansion of Sliding Window Method for Finding Shorter Addition/Subtraction-Chains

    OpenAIRE

    Younho Lee; Heeyoul Kim; Seong-Min Hong; Hyunsoo Yoon

    2006-01-01

    Finding a shorter addition/subtraction-chain for an integer is an important problem for many cryptographic systems based on number theory. Especially, execution time of multiplication on an elliptic curve cryptosystem is directly proportional to the length of the addition/subtraction-chain. In this paper, we propose an algorithm to find an addition/subtraction-chain. The proposed algorithm is based on the small-window method, and reduces the number of windows by using subtractions. We show th...

  20. Expansion of Sliding Window Method for Finding Shorter Addition/Subtraction-Chains

    Directory of Open Access Journals (Sweden)

    Younho Lee

    2006-01-01

    Full Text Available Finding a shorter addition/subtraction-chain for an integer is an important problem for many cryptographic systems based on number theory. Especially, execution time of multiplication on an elliptic curve cryptosystem is directly proportional to the length of the addition/subtraction-chain. In this paper, we propose an algorithm to find an addition/subtraction-chain. The proposed algorithm is based on the small-window method, and reduces the number of windows by using subtractions. We show the proposed algorithm finds the shorter addition/subtraction-chain than what can be found by any other previous algorithm.

  1. Optimization of the fermentation media for sophorolipid production from Candida bombicola ATCC 22214 using a simplex centroid design.

    Science.gov (United States)

    Rispoli, Fred J; Badia, Daniel; Shah, Vishal

    2010-01-01

    This article describes the use of a simplex centroid mixture experimental design to optimize the fermentation medium in the production of sophorolipids (SLs) using Candida bombicola. In the first stage, 16 media ingredients were screened for the ones that have the most positive influence on the SL production. The sixteen ingredients that were chosen are five different carbohydrates (fructose, glucose, glycerol, lactose, and sucrose), five different nitrogen sources (malt extract, peptone extract, soytone, urea, and yeast extract), two lipid sources (mineral oil and oleic acid), two phosphorus sources (K(2)HPO(4) and KH(2)PO(4)), MgSO(4), and CaCl(2). Multiple regression analysis and centroid effect analysis were carried out to find the sugar, lipid, nitrogen source, phosphorus source, and metals having the most positive influence. Sucrose, malt extract, oleic acid, K(2)HPO(4), and CaCl(2) were selected for the second stage of experiments. An augmented simplex centroid design for five ingredients requiring 16 experiments was used for the optimization stage. This produced a quadratic model developed to help understand the interaction amongst the ingredients and find the optimal media concentrations. In addition, the top three results from the optimization experiments were used to obtain constraints that identify an optimal region. The model together with the optimal region constraints predicts the maximum production of SLs when the fermentation media is composed of sucrose, 125 g/L; malt extract, 25 g/L; oleic acid, 166.67 g/L; K(2)HPO(4), 1.5 g/L; and CaCl(2), 2.5 g/L. The optimal media was validated experimentally and a yield of 177 g/L was obtained. PMID:20205261

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

    DEFF Research Database (Denmark)

    Andersen, Stig Kildegård; Thomsen, Per Grove

    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 test case. A parallel speedup factor of 23 on 33 processors was achieved with multiple shooting. But fast transients at the beginnings of sub intervals caused significant overhead for the multiple shooting methods and limited the best speedup to 3.8 relative to the fastest sequential method: Single shooting with reduced dimension of the boundary value problem.

  3. Multiscale Superpixels and Supervoxels Based on Hierarchical Edge-Weighted Centroidal Voronoi Tessellation.

    Science.gov (United States)

    Zhou, Youjie; Ju, Lili; Wang, Song

    2015-11-01

    Superpixels and supervoxels play an important role in many computer vision applications, such as image segmentation, object recognition, and video analysis. In this paper, we propose a new hierarchical edge-weighted centroidal Voronoi tessellation (HEWCVT) method for generating superpixels/supervoxels in multiple scales. In this method, we model the problem as a multilevel clustering process: superpixels/supervoxels in one level are clustered to obtain larger size superpixels/supervoxels in the next level. In the finest scale, the initial clustering is directly conducted on pixels/voxels. The clustering energy involves both color similarities and boundary smoothness of superpixels/supervoxels. The resulting superpixels/supervoxels can be easily represented by a hierarchical tree which describes the nesting relation of superpixels/supervoxels across different scales. We first investigate the performance of obtained superpixels/supervoxels under different parameter settings, then we evaluate and compare the proposed method with several state-of-the-art superpixel/supervoxel methods on standard image and video data sets. Both quantitative and qualitative results show that the proposed HEWCVT method achieves superior or comparable performances with other methods. PMID:26111396

  4. Methods for synthesizing findings on moderation effects across multiple randomized trials.

    Science.gov (United States)

    Brown, C Hendricks; Sloboda, Zili; Faggiano, Fabrizio; Teasdale, Brent; Keller, Ferdinand; Burkhart, Gregor; Vigna-Taglianti, Federica; Howe, George; Masyn, Katherine; Wang, Wei; Muthén, Bengt; Stephens, Peggy; Grey, Scott; Perrino, Tatiana

    2013-04-01

    This paper presents new methods for synthesizing results from subgroup and moderation analyses across different randomized trials. We demonstrate that such a synthesis generally results in additional power to detect significant moderation findings above what one would find in a single trial. Three general methods for conducting synthesis analyses are discussed, with two methods, integrative data analysis and parallel analyses, sharing a large advantage over traditional methods available in meta-analysis. We present a broad class of analytic models to examine moderation effects across trials that can be used to assess their overall effect and explain sources of heterogeneity, and present ways to disentangle differences across trials due to individual differences, contextual level differences, intervention, and trial design. PMID:21360061

  5. A New Method for Finding the Thevenin and Norton Equivalent Circuits

    OpenAIRE

    George E. Chatzarakis

    2010-01-01

    The paper presents a new pedagogical method for finding the Thevenin and Norton equivalent circuits of a linear electric circuit (LEC) at the n-different pairs of terminals simultaneously, regardless of the circuit topology and complexity. The proposed method is appropriate for undergraduate electrical and electronic engineering students leading to straightforward solutions, mostly arrived at by inspection, so that it can be regarded as a simple and innovative calculation tool for Thevenin eq...

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

    DEFF Research Database (Denmark)

    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 test case. A parallel speedup factor of 23 on 33 processors was achieved with multiple shooting. But fast transients at the beginnings of sub intervals caused significant overhead for the multiple shoot...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    CERN Document Server

    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).

  9. "Expectations to Change" ((E2C): A Participatory Method for Facilitating Stakeholder Engagement with Evaluation Findings

    Science.gov (United States)

    Adams, Adrienne E.; Nnawulezi, Nkiru A.; Vandenberg, Lela

    2015-01-01

    From a utilization-focused evaluation perspective, the success of an evaluation is rooted in the extent to which the evaluation was used by stakeholders. This paper details the "Expectations to Change" (E2C) process, an interactive, workshop-based method designed to engage primary users with their evaluation findings as a means of…

  10. Error-finding and error-correcting methods for the start-up of the SLC

    International Nuclear Information System (INIS)

    During the commissioning of an accelerator, storage ring, or beam transfer line, one of the important tasks of an accelertor physicist is to check the first-order optics of the beam line and to look for errors in the system. Conceptually, it is important to distinguish between techniques for finding the machine errors that are the cause of the problem and techniques for correcting the beam errors that are the result of the machine errors. In this paper we will limit our presentation to certain applications of these two methods for finding or correcting beam-focus errors and beam-kick errors that affect the profile and trajectory of the beam respectively. Many of these methods have been used successfully in the commissioning of SLC systems. In order not to waste expensive beam time we have developed and used a beam-line simulator to test the ideas that have not been tested experimentally. To save valuable physicist's time we have further automated the beam-kick error-finding procedures by adopting methods from the field of artificial intelligence to develop a prototype expert system. Our experience with this prototype has demonstrated the usefulness of expert systems in solving accelerator control problems. The expert system is able to find the same solutions as an expert physicist but in a more systematic fashion. The methods used in these procedures and some of the recent applications will be described in this paper

  11. Error-finding and error-correcting methods for the start-up of the SLC

    International Nuclear Information System (INIS)

    During the commissioning of an accelerator, storage ring, or beam transfer line, one of the important tasks of an accelerator physicist is to check the first-order optics of the beam line and to look for errors in the system. Conceptually, it is important to distinguish between techniques for finding the machine errors that are the cause of the problem and techniques for correcting the beam errors that are the result of the machine errors. In this paper the authors limit their presentation to certain applications of these two methods for finding or correcting beam-focus errors and beam-kick errors that affect the profile and trajectory of the beam respectively. Many of these methods have been used successfully in the commissioning of SLC systems. In order not to waste expensive beam time they have developed and used a beam-line simulator to test the ideas that have not been tested experimentally. To save valuable physicist's time they have further automated the beam-kick error-finding procedures by adopting methods from the field of artificial intelligence to develop a prototype expert system. The authors' experience with this prototype has demonstrated the usefulness of expert systems in solving accelerator control problems. The expert system is able to find the same solutions as an expert physicist but in a more systematic fashion. The methods used in these procedures and some of the recent applications are described in this paper

  12. Variation of acoustic mode centroid frequencies over the solar cycle

    Science.gov (United States)

    Chaplin, W. J.; Appourchaux, T.; Elsworth, Y.; Isaak, G. R.; New, R.

    Together with a brief historical overview, we use high-quality helioseismic data collected by three different observational programmes during the declining phase of activity cycle 22, and a substantial portion of the rising phase of the current cycle (23), to study the phenomenological nature of the cycle-induced (centroid) eigenfrequencies. Our analyses (for 1600 ? ? ? 4000 ?Hz) make use of observations made by the ground-based GONG over the angular degree range 4 ? l ? 150; the ground-based BiSON over 0 ? l ? 2; and the VIRGO/LOI instrument on board the ESA/NASA SOHO satellite over 0 ? l ? 8. We show that GONG shifts averaged over different ranges in l, together with the BiSON and LOI data averaged over their full quoted ranges, all scale at a given frequency with the normalized mode inertia ratio Qnl (Christensen-Dalsgaard & Berthomieu 1991). This is to be expected if the time-dependent perturbation affecting the modes is confined in the surface layers; the excellent agreement also reflects favourably on the external consistency of the different observations. We have also analyzed the frequency dependence of the shifts by fitting a power-law of the form ?? nl ? (? nl/ Enl to the data (where the Enl are the mode inertias, and ? is the power-law index to be extracted). Previous studies have suggested that a relation with ? = 0 provides an adequate description of the shifts up to ? ? 3500 ?Hz. However, here we show that while nevertheless describing the shifts well up to ˜ 2500 ?Hz, the linear scaling breaks down conspicuously at higher frequencies. Above this threshold, the shifts follow a power-law dependence with ? ˜ 2.

  13. Seismotectonics of Morocco from regional centroid moment tensors

    Science.gov (United States)

    Villaseñor, Antonio; el Moudnib, Lahcen; Herrmann, Robert B.; Harnafi, Mimoun

    2014-05-01

    We have obtained new regional centroid moment tensors (RCMTs) for 35 earthquakes occurred in Morocco and vicinity between 2008 and 2012. During this time period an unprecedented number of broadband stations (more than 100) were operating in the region, providing high-quality waveform data that were used to obtain RCMTs from waveform inversion. The main part of this dataset was composed of temporary broadband stations that were concurrently deployed in different seismic experiments (i.e. IberArray, PICASSO, Muenster, Bristol). The events analyzed in this study are moderate in size, ranging in moment magnitude Mw from 3.5 to 4.8. Their predominant mechanisms correspond to reverse and strike-slip faulting, although normal and "mixed" mechanisms are also observed. In spite of this variability in mechanism type, when analyzed in terms of the orientation of the P (compression) axes two major groups can be distinguished. The first group, corresponding to earthquakes in the Altas and NE Morocco is characterized by near-horizontal P axes oriented in an approximately NW-SE direction that coincides with the direction of convergence between Africa and Eurasia. A small clockwise rotation of the orientation of the P axes is observed from eastern Morocco to the western Atlas. The second group corresponds to earthquakes in the western Rif, that are characterized also by horizontal P axes, but oriented in a SW-NE direction, almost perpendicular to the first group. These earthquakes are part of a cluster located north of Ouezzane. The mechanisms in this second cluster are consistent with recent GPS results that show that the western Rif is moving in a SW direction with respect to the African (Nubia) plate.

  14. A new method for direction finding based on Markov random field model

    Science.gov (United States)

    Ota, Mamoru; Kasahara, Yoshiya; Goto, Yoshitaka

    2015-07-01

    Investigating the characteristics of plasma waves observed by scientific satellites in the Earth's plasmasphere/magnetosphere is effective for understanding the mechanisms for generating waves and the plasma environment that influences wave generation and propagation. In particular, finding the propagation directions of waves is important for understanding mechanisms of VLF/ELF waves. To find these directions, the wave distribution function (WDF) method has been proposed. This method is based on the idea that observed signals consist of a number of elementary plane waves that define wave energy density distribution. However, the resulting equations constitute an ill-posed problem in which a solution is not determined uniquely; hence, an adequate model must be assumed for a solution. Although many models have been proposed, we have to select the most optimum model for the given situation because each model has its own advantages and disadvantages. In the present study, we propose a new method for direction finding of the plasma waves measured by plasma wave receivers. Our method is based on the assumption that the WDF can be represented by a Markov random field model with inference of model parameters performed using a variational Bayesian learning algorithm. Using computer-generated spectral matrices, we evaluated the performance of the model and compared the results with those obtained from two conventional methods.

  15. Statistical Properties of Line Centroid Velocity Increments in the rho Ophiuchi Cloud

    OpenAIRE

    Lis, D. C.; Keene, Jocelyn; Li, Y.; ~Phillips, T. G.; Pety, J.

    1998-01-01

    We present a comparison of histograms of CO (2-1) line centroid velocity increments in the rho Ophiuchi molecular cloud with those computed for spectra synthesized from a three-dimensional, compressible, but non-star-forming and nongravitating, hydrodynamic simulation. Histograms of centroid velocity increments in the rho Oph cloud clearly show non-Gaussian wings similar to those found in histograms of velocity increments and derivatives in experimental studies of laboratory and atmospheric f...

  16. Localization Algorithm based on Improved Weighted Centroid in Wireless Sensor Networks

    OpenAIRE

    Shyi-Ching Liang; LunHao Liao; Yen-Chun Lee

    2014-01-01

    Location technology is becoming more and more important in wireless sensor networks. The weighted centroid localization offers a fast and simple algorithm for the location equipment in wireless sensor networks. The algorithm derives from the centroid measurement and calculation device of the adjacent anchor in the average coordinate. After the analysis of the radio propagation loss model, the most appropriate log-distance distribution model is selected to simulate the signal propagation. Base...

  17. Centroid shift analysis of microlens array detector in interference imaging system

    Science.gov (United States)

    Zhao, Zhu; Hui, Mei; Liu, Ming; Dong, Liquan; Liu, Xiaohua; Zhao, Yuejin

    2015-11-01

    Most CCD imaging detectors integrated microlens arrays (MLAs) to increase fill factor and sensitivity. However, they also introduce spot calibration issues with the inconsistency of spot geometry center and intensity distribution center. We setup theoretical and experimental models to research the problem of centroid shifting. According to the Seidel and Zernike coefficients of the optical model, we analyze main aberrations of microlens. In "Chief Ray" and "Centroid" reference frames, centroid shift numerical value is calculated with Geometric Ensquared Energy (GEE). Based on pentaprism test for 8.4 m mirror segment, we conduct spot imaging experiment in interference system. Spots images are obtained, and two-dimensional centroid algorithm processing is performed on them to get the analog experiment values of centroid movements. The results show that the MLA placed in KAI-16000 imaging detector causes the spot centroid to move. When there is a 14° (or -14°) angle of incident ray, the shifting values are about 1.46 ?m in simulation and 2.18 ?m in experiment. Our research makes a contribution to the compensation of calibrated error in metrology technology. We also prove that a significant portion of the shift comes from the low order aberration of microlens.

  18. The impact of the in-orbit background and the X-ray source intensity on the centroiding accuracy of the Swift X-ray telescope

    International Nuclear Information System (INIS)

    The optical components of the Swift Gamma Ray Burst Explorer X-ray Telescope (XRT), consisting of the JET-X spare flight mirror and a charge coupled device of the type used in the EPIC program, were used in a re-calibration study carried out at the Panter facility, which is part of the Max Plank Institute for Extraterrestrial Physics. The objective of this study was to check the focal length and the off axis performance of the mirrors and to show that the half energy width (HEW) of the on-axis point spread function (PSF) was of the order of 16 arcsec at 1.5 keV (Nucl. Instr. and Meth. A 488 (2002) 543; SPIE 4140 (2000) 64) and that a centroiding accuracy better that 1 arcsec could be achieved within the 4 arcmin sampling area designated by the Burst Alert Telescope (Nucl. Instr. and Meth. A 488 (2002) 543). The centroiding accuracy of the Swift XRT's optical components was tested as a function of distance from the focus and off axis position of the PSF (Nucl. Instr. and Meth. A 488 (2002) 543). The presence of background events in the image frame introduced errors in the centroiding process, making the choice of centroiding algorithm important (Nucl. Instr. and Meth. A 488 (2002) 543). Since the objective of Swift is to rapidly investigate the X-ray afterglows of Gamma Ray Bursts the possibility of detecting a bright source with intensity greater than 25 Crab could not be excluded and therefore the impact of a saturated PSF core on the centroiding accuracy was investigated by experimental methods

  19. Single-ended transition state finding with the growing string method.

    Science.gov (United States)

    Zimmerman, Paul M

    2015-04-01

    Reaction path finding and transition state (TS) searching are important tasks in computational chemistry. Methods that seek to optimize an evenly distributed set of structures to represent a chemical reaction path are known as double-ended string methods. Such methods can be highly reliable because the endpoints of the string are fixed, which effectively lowers the dimensionality of the reaction path search. String methods, however, require that the reactant and product structures are known beforehand, which limits their ability for systematic exploration of reactive steps. In this article, a single-ended growing string method (GSM) is introduced which allows for reaction path searches starting from a single structure. The method works by sequentially adding nodes along coordinates that drive bonds, angles, and/or torsions to a desired reactive outcome. After the string is grown and an approximate reaction path through the TS is found, string optimization commences and the exact TS is located along with the reaction path. Fast convergence of the string is achieved through use of internal coordinates and eigenvector optimization schemes combined with Hessian estimates. Comparison to the double-ended GSM shows that single-ended method can be even more computationally efficient than the already rapid double-ended method. Examples, including transition metal reactivity and a systematic, automated search for unknown reactivity, demonstrate the efficacy of the new method. This automated reaction search is able to find 165 reaction paths from 333 searches for the reaction of NH3 BH3 and (LiH)4 , all without guidance from user intuition. PMID:25581279

  20. Finite difference method to find period-one gait cycles of simple passive walkers

    Science.gov (United States)

    Dardel, Morteza; Safartoobi, Masoumeh; Pashaei, Mohammad Hadi; Ghasemi, Mohammad Hassan; Navaei, Mostafa Kazemi

    2015-01-01

    Passive dynamic walking refers to a class of bipedal robots that can walk down an incline with no actuation or control input. These bipeds are sensitive to initial conditions due to their style of walking. According to small basin of attraction of passive limit cycles, it is important to start with an initial condition in the basin of attraction of stable walking (limit cycle). This paper presents a study of the simplest passive walker with point and curved feet. A new approach is proposed to find proper initial conditions for a pair of stable and unstable period-one gait limit cycles. This methodology is based on finite difference method which can solve the nonlinear differential equations of motion on a discrete time. Also, to investigate the physical configurations of the walkers and the environmental influence such as the slope angle, the parameter analysis is applied. Numerical simulations reveal the performance of the presented method in finding two stable and unstable gait patterns.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

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

    OpenAIRE

    WAGNER, KARLA D.; Davidson, Peter J.; Pollini, Robin A; STRATHDEE, Steffanie A; 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...

  4. Methods and findings of a systems interaction study of a Westinghouse PWR

    International Nuclear Information System (INIS)

    This paper describes the methods and findings of a systems interaction study of a Westinghouse PWR. BNL conducted the study as a methods application that was performed to support the resolution of Unresolved Safety Issue A-17 on Systems Interactions. The method calls for a fault tree model of the plant to be developed in stages, corresponding to successively increasing levels of scope and detail. A functional model is developed first, resolved only to sufficient detail to reflect support system dependences; this guides the subsequent searches for spatial and induced-human interactions. This process has led to the identification of an active single failure causing loss of low pressure injection following a large or medium LOCA

  5. Minima Hopping Accelerated Path Search: An Efficient Method for Finding Complex Chemical Reaction Pathways

    CERN Document Server

    Schaefer, Bastian; Amsler, Maximilian; Goedecker, Stefan

    2014-01-01

    Based on Minima Hopping and its capabilities of exploring potential energy surfaces we have developed Minima Hopping Accelerated Path Search (MHAPS) which is a novel algorithm for efficiently finding the reaction paths of complex chemical reactions by sampling collections of energetically low-lying minima and first order saddle points of potential energy surfaces. For this new reaction path search method we developed a highly reliable approach for computing saddle points which is based on the idea of a bar rolling downwards the potential energy landscape. For Lennard-Jones benchmark systems, Minima Hopping Accelerated Path Search was compared to a known mode-following based approach for sampling collections of minima and first order transition states. Although we used a stabilized mode-following technique that reliably allows to follow distinct directions that are defined by the eigenvectors of the Hessian matrix, we observed that Minima Hopping Accelerated Path Search is far superior in finding lowest-barrie...

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

    DEFF Research Database (Denmark)

    Maronsson, Jon Bergmann; Jónsson, Hannes

    2012-01-01

    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. The method is based on a string of discretisation points along a path between the first order saddle points and using an iterative optimisation which requires only the force acting on the atoms. At each iteration during the optimisation, the force is inverted along an unstable eigenmode perpendicular 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 integral along the ridge.

  7. Experimental determination of Philodendron melinonii and Arabidopsis thaliana tissue microstructure and geometric modeling via finite-edge centroidal Voronoi tessellation

    Science.gov (United States)

    Faisal, Tanvir R.; Hristozov, Nicolay; Rey, Alejandro D.; Western, Tamara L.; Pasini, Damiano

    2012-09-01

    Plant petioles and stems are hierarchical cellular structures, displaying structural features defined at multiple length scales. One or more of the intermediate hierarchical levels consists of tissues, in which the cellular distribution is quasirandom. The current work focuses on the realistic modeling of plant tissue microstructures. The finite-edge centroidal Voronoi tessellation (FECVT) is here introduced to overcome the drawbacks of the semi-infinite edges of a typical Voronoi model. FECVT can generate a realistic model of a tissue microstructure, which might have finite edges at its border, be defined by a boundary contour of any shape, and include complex heterogeneity and cellular gradients. The centroid-based Voronoi tessellation is applied to model the microstructure of the Philodendron melinonii petiole and the Arabidopsis thaliana stem, which both display intense cellular gradients. FECVT coupled with a digital image processing algorithm is implemented to capture the nonperiodic microstructures of plant tissues. The results obtained via this method satisfactorily obey the geometric, statistical, and topological laws of naturally evolved cellular solids. The predicted models are also validated by experimental data.

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Centroid Position as a Function of Total Counts in a Windowed CMOS Image of a Point Source

    Energy Technology Data Exchange (ETDEWEB)

    Wurtz, R E; Olivier, S; Riot, V; Hanold, B J; Figer, D F

    2010-05-27

    We obtained 960,200 22-by-22-pixel windowed images of a pinhole spot using the Teledyne H2RG CMOS detector with un-cooled SIDECAR readout. We performed an analysis to determine the precision we might expect in the position error signals to a telescope's guider system. We find that, under non-optimized operating conditions, the error in the computed centroid is strongly dependent on the total counts in the point image only below a certain threshold, approximately 50,000 photo-electrons. The LSST guider camera specification currently requires a 0.04 arcsecond error at 10 Hertz. Given the performance measured here, this specification can be delivered with a single star at 14th to 18th magnitude, depending on the passband.

  10. Performance of centroiding algorithms at low light level conditions in adaptive optics

    CERN Document Server

    Vyas, Akondi; Prasad, B Raghavendra; 10.1109/ARTCom.2009.30

    2010-01-01

    The performance metrics of different centroiding algorithms at low light level conditions were optimized in the case of a Shack Hartmann Sensor (SHS) for efficient performance of the adaptive optics system. For short exposures and low photon flux, the Hartmann spot does not have a Gaussian shape due to the photon noise which follows Poissonian statistics. The centroiding estimation error was calculated at different photon levels in the case of changing spot size and shift in the spot using Monte Carlo simulations. This analysis also proves to be helpful in optimizing the SHS specifications at low light levels.

  11. Using a complete spectroscopic survey to find red quasars and test the KX method

    CERN Document Server

    Jurek, Russell J; Francis, Paul J; Pimbblet, Kevin A

    2007-01-01

    We present an investigation of quasar colour-redshift parameter space in order to search for radio-quiet red quasars and to test the ability of a variant of the KX quasar selection method to detect quasars over a full range of colour without bias. This is achieved by combining IRIS2 imaging with the complete Fornax Cluster Spectroscopic Survey to probe parameter space unavailable to other surveys. We construct a new sample of 69 quasars with measured bJ - K colours. We show that the colour distribution of these quasars is significantly different from that of the Large Bright Quasar Survey's quasars at a 99.9% confidence level. We find 11 of our sample of 69 quasars have signifcantly red colours (bJ - K >= 3.5) and from this, we estimate the red quasar fraction of the K <= 18.4 quasar population to be 31%, and robustly constrain it to be at least 22%. We show that the KX method variant used here is more effective than the UVX selection method, and has less colour bias than optical colour-colour selection me...

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

    Science.gov (United States)

    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 statistical approach to match absorbers with galaxies near the quasar lines of sight. Of the 75 quasars observed with HST/Cosmic Origins Spectrograph (COS) and archived on the Mikulski Archive for Space Telescopes (MAST), 39 overlap with the footprint of the Sloan 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.

  13. Quantum Imaging beyond the Diffraction Limit by Centroid Measurements

    CERN Document Server

    Tsang, Mankei

    2009-01-01

    I propose a quantum imaging method that can beat the Rayleigh-Abbe diffraction limit and achieve de Broglie resolution without requiring a multiphoton absorber as the detector. Using the same non-classical states of light as those for quantum lithography, the proposed method requires only intensity measurements, followed by image post-processing, to produce the same complex image patterns as those in quantum lithography. The method is expected to be experimentally realizable using current technology.

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Multiple-precision zero-finding methods and the complexity of elementary function evaluation

    CERN Document Server

    Brent, Richard P

    2010-01-01

    We consider methods for finding high-precision approximations to simple zeros of smooth functions. As an application, we give fast methods for evaluating the elementary functions log(x), exp(x), sin(x) etc. to high precision. For example, if x is a positive floating-point number with an n-bit fraction, then (under rather weak assumptions) an n-bit approximation to log(x) or exp(x) may be computed in time asymptotically equal to 13M(n)lg(n), where M(n) is the time required to multiply floating-point numbers with n-bit fractions. Similar results are given for the other elementary functions. Some analogies with operations on formal power series (over a field of characteristic zero) are discussed. In particular, it is possible to compute the first n terms in log(1 + a_1.x + ...) or exp(a_1.x + ...) in time O(M(n)), where M(n) is the time required to multiply two polynomials of degree n - 1. It follows that the first n terms in a q-th power (1 + a_1.x + ...)^q can be computed in time O(M(n)), independent of q. One...

  16. School locations and traffic emissions—environmental (in)justice findings using a new screening method.

    Science.gov (United States)

    Gaffron, Philine; Niemeier, Deb

    2015-02-01

    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. PMID:25679341

  17. Centroid-based summarization of multiple documents: sentence extraction, utility-based evaluation, and user studies

    OpenAIRE

    Radev, Dragomir R.; Jing, Hongyan; Budzikowska, Malgorzata

    2000-01-01

    We present a multi-document summarizer, called MEAD, which generates summaries using cluster centroids produced by a topic detection and tracking system. We also describe two new techniques, based on sentence utility and subsumption, which we have applied to the evaluation of both single and multiple document summaries. Finally, we describe two user studies that test our models of multi-document summarization.

  18. Finger vein identification using fuzzy-based k-nearest centroid neighbor classifier

    Science.gov (United States)

    Rosdi, Bakhtiar Affendi; Jaafar, Haryati; Ramli, Dzati Athiar

    2015-02-01

    In this paper, a new approach for personal identification using finger vein image is presented. Finger vein is an emerging type of biometrics that attracts attention of researchers in biometrics area. As compared to other biometric traits such as face, fingerprint and iris, finger vein is more secured and hard to counterfeit since the features are inside the human body. So far, most of the researchers focus on how to extract robust features from the captured vein images. Not much research was conducted on the classification of the extracted features. In this paper, a new classifier called fuzzy-based k-nearest centroid neighbor (FkNCN) is applied to classify the finger vein image. The proposed FkNCN employs a surrounding rule to obtain the k-nearest centroid neighbors based on the spatial distributions of the training images and their distance to the test image. Then, the fuzzy membership function is utilized to assign the test image to the class which is frequently represented by the k-nearest centroid neighbors. Experimental evaluation using our own database which was collected from 492 fingers shows that the proposed FkNCN has better performance than the k-nearest neighbor, k-nearest-centroid neighbor and fuzzy-based-k-nearest neighbor classifiers. This shows that the proposed classifier is able to identify the finger vein image effectively.

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

    Science.gov (United States)

    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…

  20. 4D tumor centroid tracking using orthogonal 2D dynamic MRI: Implications for radiotherapy planning

    Energy Technology Data Exchange (ETDEWEB)

    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

    Purpose: Current pretreatment, 4D imaging techniques are suboptimal in that they sample breathing motion over a very limited “snapshot” in time. Heretofore, long-duration, 4D motion characterization for radiotherapy planning, margin optimization, and validation have been impractical for safety reasons, requiring invasive markers imaged under x-ray fluoroscopy. To characterize 3D tumor motion and associated variability over durations more consistent with treatments, the authors have developed a practical dynamic MRI (dMRI) technique employing two orthogonal planes acquired in a continuous, interleaved fashion.Methods: 2D balanced steady-state free precession MRI was acquired continuously over 9–14 min at approximately 4 Hz in three healthy volunteers using a commercial 1.5 T system; alternating orthogonal imaging planes (sagittal, coronal, sagittal, etc.) were employed. The 2D in-plane pixel resolution was 2 × 2 mm{sup 2} with a 5 mm slice profile. Simultaneous with image acquisition, the authors monitored a 1D surrogate respiratory signal using a device available with the MRI system. 2D template matching-based anatomic feature registration, or tracking, was performed independently in each orientation. 4D feature tracking at the raw frame rate was derived using spline interpolation.Results: Tracking vascular features in the lung for two volunteers and pancreatic features in one volunteer, the authors have successfully demonstrated this method. Registration error, defined here as the difference between the sagittal and coronal tracking result in the SI direction, ranged from 0.7 to 1.6 mm (1?) which was less than the acquired image resolution. Although the healthy volunteers were instructed to relax and breathe normally, significantly variable respiration was observed. To demonstrate potential applications of this technique, the authors subsequently explored the intrafraction stability of hypothetical tumoral internal target volumes and 3D spatial probability 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.

  1. 4D tumor centroid tracking using orthogonal 2D dynamic MRI: Implications for radiotherapy planning

    International Nuclear Information System (INIS)

    Purpose: Current pretreatment, 4D imaging techniques are suboptimal in that they sample breathing motion over a very limited “snapshot” in time. Heretofore, long-duration, 4D motion characterization for radiotherapy planning, margin optimization, and validation have been impractical for safety reasons, requiring invasive markers imaged under x-ray fluoroscopy. To characterize 3D tumor motion and associated variability over durations more consistent with treatments, the authors have developed a practical dynamic MRI (dMRI) technique employing two orthogonal planes acquired in a continuous, interleaved fashion.Methods: 2D balanced steady-state free precession MRI was acquired continuously over 9–14 min at approximately 4 Hz in three healthy volunteers using a commercial 1.5 T system; alternating orthogonal imaging planes (sagittal, coronal, sagittal, etc.) were employed. The 2D in-plane pixel resolution was 2 × 2 mm2 with a 5 mm slice profile. Simultaneous with image acquisition, the authors monitored a 1D surrogate respiratory signal using a device available with the MRI system. 2D template matching-based anatomic feature registration, or tracking, was performed independently in each orientation. 4D feature tracking at the raw frame rate was derived using spline interpolation.Results: Tracking vascular features in the lung for two volunteers and pancreatic features in one volunteer, the authors have successfully demonstrated this method. Registration error, defined here as the difference between the sagittal and coronal tracking result in the SI direction, ranged from 0.7 to 1.6 mm (1?) which was less than the acquired image resolution. Although the healthy volunteers were instructed to relax and breathe normally, significantly variable respiration was observed. To demonstrate potential applications of this technique, the authors subsequently explored the intrafraction stability of hypothetical tumoral internal target volumes and 3D spatial probability 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

  2. A Method to Find Generic Thresholds for Identifying Relevant Physical Activity Events in Sensor Data.

    Science.gov (United States)

    Marschollek, Michael

    2016-01-01

    The increasing use of wearable actimetry devices in cohort studies can provide a deep and objective insight in physical activity (PA) patterns. For reliable and reproducible pattern recognition, and to minimize the influence of specific device characteristics, there is a need for a generic method to identify relevant PA events in sensor data sets on the basis of comprehensive features such as PA duration and intensity. The objectives of this paper are to present a method to identify universal event detection thresholds for such parameters, and to attempt to find stable meta-clusters of PA behaviour. PA events of 5, 10, 20 and 30 min with low, medium and high intensity thresholds found in literature and intensity deciles were computed for a random sample (N?=?100) of the NHANES 2005-06 accelerometer data set (N?=?7457). On the basis of all combinations of the above, activity events were detected, and parameters mean duration, mean intensity and event regularity were computed. Results were clustered using x-Means clustering and visualized for 5-, 10-, 20-, and 30-min events. Stable clustering results are obtained with intensity thresholds up to the 8th decile and for event durations up to 10 min. Two stable meta-clusters were detected: 'irregularly active' (intensity at 52nd percentile) and 'regularly active' (intensity at 42nd percentile). Distinct generic thresholds could be identified and are proposed. They may prove useful for further investigations of similar actimetry data sets, minimising the influence of specific device characteristics. The results also confirm that distinct PA event patterns - including event regularity - can be identified using wearable sensor devices, especially when regarding low-intensity, short-term activities which do not correspond to current PA recommendations. Further research is necessary to evaluate actual associations between sensor-based PA parameters and health outcome. The author identified generic intensity and duration thresholds for analysing objective PA data from wearable devices. This may contribute to further analyses of PA patterns along with their relations with health outcome parameters. PMID:26547849

  3. Moving Domestic Robotics Control Method Based on Creating and Sharing Maps with Shortest Path Findings and Obstacle Avoidance

    Directory of Open Access Journals (Sweden)

    Kohei Arai

    2013-02-01

    Full Text Available Control method for moving robotics in closed areas based on creation and sharing maps through shortest path findings and obstacle avoidance is proposed. Through simulation study, a validity of the proposed method is confirmed. Furthermore, the effect of map sharing among robotics is also confirmed together with obstacle avoidance with cameras and ultrasonic sensors.

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

    CERN Document Server

    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.

  5. Optimization of soy isoflavone extraction with different solvents using the simplex-centroid mixture design.

    Science.gov (United States)

    Yoshiara, Luciane Yuri; Madeira, Tiago Bervelieri; Delaroza, Fernanda; da Silva, Josemeyre Bonifácio; Ida, Elza Iouko

    2012-12-01

    The objective of this study was to optimize the extraction of different isoflavone forms (glycosidic, malonyl-glycosidic, aglycone and total) from defatted cotyledon soy flour using the simplex-centroid experimental design with four solvents of varying polarity (water, acetone, ethanol and acetonitrile). The obtained extracts were then analysed by high-performance liquid chromatography. The profile of the different soy isoflavones forms varied with different extractions solvents. Varying the solvent or mixture used, the extraction of different isoflavones was optimized using the centroid-simplex mixture design. The special cubic model best fitted to the four solvents and its combination for soy isoflavones extraction. For glycosidic isoflavones extraction, the polar ternary mixture (water, acetone and acetonitrile) achieved the best extraction; malonyl-glycosidic forms were better extracted with mixtures of water, acetone and ethanol. Aglycone isoflavones, water and acetone mixture were best extracted and total isoflavones, the best solvents were ternary mixture of water, acetone and ethanol. PMID:22621769

  6. Alternatives for implementing methods for finding agents in a Multi-Agent Systems

    OpenAIRE

    Tucat, Mariano; García, Alejandro Javier

    2006-01-01

    Interaction is an essential characteristic of Multi- Agent Systems (MASs). Agents that are part of a MAS usually interact by exchanging messages accord- ing to some conversation policy. Therefore, the ability to find other agents and exchange messages with them are features that need to be implemented in agents that are part of a MAS. Finding an agent means been aware of it existence and obtaining the information needed to send to it a message. There exists different alternatives of implement...

  7. Sum rules for isospin centroids in pick-up reactions on general multishell target states

    OpenAIRE

    Bansal, R. K.; Sharda, H.; KUMAR, Ashwani

    1997-01-01

    Sum Rules equations for pick-up reactions are presented for the first time for the energy centroids of states both for the isospin T_ (\\equiv T_0 + {1 \\over 2}) of the final nucleus when a nucleon is picked up from a general multishell target state with isospin T_0. These equations contain two-body correlation terms, , which, at the present moment, are difficult to handle analytically. These terms are managed by combining these equations wit...

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

    OpenAIRE

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

    2011-01-01

    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 ...

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

    OpenAIRE

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

    2012-01-01

    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 validat...

  10. Centroid and Envelope Dynamics of High-intensity Charged Particle Beams in an External Focusing Lattice and Oscillating Wobbler

    International Nuclear Information System (INIS)

    The centroid and envelope dynamics of a high-intensity charged particle beam are investigated as a beam smoothing technique to achieve uniform illumination over a suitably chosen region of the target for applications to ion-beam-driven high energy density physics and heavy ion fusion. The motion of the beam centroid projected onto the target follows a smooth pattern to achieve the desired illumination, for improved stability properties during the beam-target interaction. The centroid dynamics is controlled by an oscillating 'wobbler', a set of electrically-biased plates driven by RF voltage.

  11. Achete grilles et methodes pour recherche d'idees sans peine (Buy Grids and Painless Methods for Finding Ideas).

    Science.gov (United States)

    Yaiche, Francis

    1986-01-01

    Proposes tools and methods for teachers and students to use in the classroom to organize and stimulate ideas, imagination, memory, improvisation, and writing. Sample outlines and grids serve as methods for helping learners understand specific concepts. (MSE)

  12. The Expanded FindCore Method for Identification of a Core Atom Set for Assessment of Protein Structure Prediction

    OpenAIRE

    Snyder, David A.; Grullon, Jennifer; Huang, Yuanpeng J.; Tejero, Roberto; Montelione, Gaetano T.

    2014-01-01

    Maximizing the scientific impact of NMR-based structure determination requires robust and statistically sound methods for assessing the precision of NMR-derived structures. In particular, a method to define a core atom set for calculating superimpositions and validating structure predictions is critical to the use of NMR-derived structures as targets in the CASP competition. FindCore (D.A. Snyder and G.T. Montelione PROTEINS 2005;59:673–686) is a superimposition independent method for identif...

  13. Enhancing spatial resolution of soft x-ray CCD detectors by single-photon centroid determination

    CERN Document Server

    Amorese, Andrea; Braicovich, Lucio; Ghiringhelli, Giacomo

    2014-01-01

    In Charge Coupled Device (CCD) detectors the electrons excited upon absorption of a single x-ray photon quickly diffuse and generate charge-spots often larger than pixel dimensions. In the soft x-ray range this phenomenon drastically limits the effective spatial resolution to approximately 25\\mu m, irrespective of the pixel size. For very low fluence the charge-cloud centroid determination can be used, on each individual spot, to estimate the actual photon impact position with sub-pixel precision. The readout noise and speed, together with the charge and spatial undersampling, are the main factors limiting the accuracy of this procedure in commercial devices. We have developed and extensively tested an algorithm for efficient centroid reconstruction on images acquired by low noise detectors not designed for single photon counting. We have thus measured a position uncertainty of 6-7\\mu m in CCDs with 13.5\\mu m and 20.0\\mu m pixel size, around 1 keV photon energy. We have analyzed the centroid calculation perfo...

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

    OpenAIRE

    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...

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

    Science.gov (United States)

    Cottrell, Seth S.

    2015-09-01

    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.

  16. Establishing the soft and hard tissue area centers (centroids) for the skull and introducing a newnon-anatomical cephalometric line

    International Nuclear Information System (INIS)

    The purpose of this study was to demonstrate how to establish the area center (centroid) of both the soft and hard tissues of the outline of the lateral cephalometric skull image, and to introduce the concept of a new non-anatomical centroid line. Lateral cephalometric radiographs, size 12 x 14 inch, of fifty seven adult subjects were selected based on their pleasant, balanced profile, Class I skeletal and dental relationship and no major dental malocclusion or malrelationship. The area centers (centroids) of both soft and hard tissue skull were practically established using a customized software computer program called the m-file. Connecting the two centers introduced the concept of a new non-anatomical soft and hard centroids line. (author)

  17. METHOD FOR ESTIMATING METHANE EMISSIONS FROM UNDERGROUND COAL MINES: PRELIMINARY FINDINGS

    Science.gov (United States)

    The paper discusses the development of an improved method for estimating global methane (CH4) emissions from underground coal mining. ince emissions data presently not available for surface mines, this method is currently restricted to underground mines. The EPA has embarked on a...

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

    Indian Academy of Sciences (India)

    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.

  19. Mechanical form-Finding of the Timber Fabric Structures with Dynamic Relaxation Method

    OpenAIRE

    Nabaei, Seyed Sina; Baverel, Olivier; Weinand, Yves

    2013-01-01

    Timber Fabric structures (TFS) initiate from a correspondence between textile principles and recent industrial developments in producing cross laminated timber panels. Several individual timber strips are interlaced according to a pattern and result in an innovative space structure. The obtained three-dimensional geometry can be regarded as the relaxed configuration of deformed panels under the imposed boundary conditions. We herein propose a form-finding procedure, which reproduces this def...

  20. A Method for Finding Structured Sparse Solutions to Non-negative Least Squares Problems with Applications

    OpenAIRE

    Esser, Ernie; Lou, Yifei; Xin, Jack

    2013-01-01

    Demixing problems in many areas such as hyperspectral imaging and differential optical absorption spectroscopy (DOAS) often require finding sparse nonnegative linear combinations of dictionary elements that match observed data. We show how aspects of these problems, such as misalignment of DOAS references and uncertainty in hyperspectral endmembers, can be modeled by expanding the dictionary with grouped elements and imposing a structured sparsity assumption that the combina...

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

    DEFF Research Database (Denmark)

    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, and evidence is accumulating that this phenomenon may also be found in Eukaryotes. We here present the first comparative method, called RNA-DECODER, which explicitly takes the known protein-coding co...

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

    DEFF Research Database (Denmark)

    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 ...

  3. A psychoacoustic method to find the perceptual cues of stop consonants in natural speech

    OpenAIRE

    Li, Feipeng; Menon, Anjali; Allen, Jont B.

    2010-01-01

    Synthetic speech has been widely used in the study of speech cues. A serious disadvantage of this method is that it requires prior knowledge about the cues to be identified in order to synthesize the speech. Incomplete or inaccurate hypotheses about the cues often lead to speech sounds of low quality. In this research a psychoacoustic method, named three-dimensional deep search (3DDS), is developed to explore the perceptual cues of stop consonants from naturally produced speech. For a given s...

  4. A MODIFIED ALGORITHM FOR THRESHOLDING AND DETECTION OF FACIAL INFORMATION FROM COLOR IMAGES USING COLOR CENTROID SEGMENTATION AND CONTOURLET TRANSFORM

    Directory of Open Access Journals (Sweden)

    Sunish Kumar O S

    2011-06-01

    Full Text Available Human face detection plays an important role in many application areas such as video surveillance, human computer interface, face recognition, face search and face image database management etc. In human face detection applications, face region usually form an inconsequential part of images. Preliminary segmentation of images into regions that contain "non-face" objects and regions that may contain "face" can greatly accelerate the process of human face detection. This can be done using skin color segmentation, where given image is segmented based on color as 'skin region' and 'non skin regions'. Thus we can say that the skin regions may contain face and other regions don't. Color information based methods take a great attention, because colors have obviously character and robust visual cue for detection. This paper proposes a method based on RGB color centroids segmentation (CCS for face detection. This paper includes two parts, first part is color image thresholding based on CCS to perform skin color segmentation and the then detection of human face from detected skin regions. CCS method has some shortcomings as it fails when the skin color of the subject lacks chroma. This happens especially with subjects having too darker or too lighter skin tones. This shortcoming of CCS can be overcome using Contourlet Transformation. In this paper, we pursue a two dimensional transform that can capture the intrinsic geometrical structure that is key in visual information.

  5. A Modified Algorithm for Thresholding and Detection of Facial Information From Color Images Using Color Centroid Segmentation and Contourlet Transform

    Directory of Open Access Journals (Sweden)

    Sunish Kumar O S

    2011-09-01

    Full Text Available Human face detection plays an important role in many application areas such as video surveillance, human computer interface, face recognition, face search and face image database management etc. In human face detection applications, face region usually form an inconsequential part of images. Preliminary segmentation of images into regions that contain "non-face" objects and regions that may contain "face" can greatly accelerate the process of human face detection. This can be done using skin color segmentation, where given image is segmented based on color as 'skin region' and 'non skin regions'. Thus we can say that the skin regions may contain face and other regions don't. Color information based methods take a great attention, because colors have obviously character and robust visual cue for detection. This paper proposes a method based on RGB color centroids segmentation (CCS for face detection. This paper includes two parts, first part is color image thresholding based on CCS to perform skin color segmentation and the then detection of human face from detected skin regions. CCS method has some shortcomings as it fails when the skin color of the subject lacks chroma. This happens especially with subjects having too darker or too lighter skin tones. This shortcoming of CCS can be overcome using Contourlet Transformation. In this paper, we pursue a two dimensional transform that can capture the intrinsic geometrical structure that is key in visual information.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. Methods to find aponeurosis and tendon stiffness and the onset of muscle contraction.

    Science.gov (United States)

    Delgado-Lezama, R; Raya, J G; Muñoz-Martínez, E J

    1997-12-30

    A method to measure small movements of living tissues either large or small is presented. The method is based on the detection of changes in reflected infrared light. An optocoupler (coupled photodiode and photodetector) and a small (b) detection of tendon and aponeurosis movements in large muscles (cat soleus); (c) detection of the onset of muscle contraction. Movements of less than 1 microm can be detected with the aid of automatic averaging of the signals. Concerning the second use (b), it permits the estimation of tendon stretch. Concerning the third use, the onset of muscle movement precedes by at least 2 ms that of the force recorded at the tendon. PMID:9497008

  8. Method for finding the critical temperature of the island in a SET structure

    Energy Technology Data Exchange (ETDEWEB)

    Toppari, J J; Kuehn, T; Halvari, A P [NanoScience Center, Department of Physics, University of Jyvaskyla, PO Box 35 (YN), FIN-40014 University of Jyvaskyla (Finland); Paraoanu, G S [Low Temperature Laboratory, Helsinki University of Technology, PO Box 5100, FIN-02015 TKK (Finland)], E-mail: paraoanu@cc.hut.fi

    2009-02-01

    We present a method to measure the critical temperature of the island of a superconducting single electron transistor. The method is based on a sharp change in the slope of the zero-bias conductance as a function of temperature. We have used this method to determine the superconducting phase transition temperature of the Nb island of an superconducting single electron transistor with Al leads. We obtain T{sub c}{sup Nb} as high as 8.5 K and gap energies up to {delta}Nb {approx_equal} 1.45 meV. By looking at the zero bias conductance as a function of magnetic field instead of temperature, also the critical field of the island can be determined. Using the orthodox theory, we have performed extensive numerical simulations of charge transport properties in the SET at temperatures comparable to the gap, which match very well the data, therefore providing a solid theoretical basis for our method. PACS: 73.23.Hk,73.40.Gk,74.50.+r.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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

  12. LGA: a method for finding 3D similarities in protein structures

    OpenAIRE

    Zemla, Adam

    2003-01-01

    We present the LGA (Local-Global Alignment) method, designed to facilitate the comparison of protein structures or fragments of protein structures in sequence dependent and sequence independent modes. The LGA structure alignment program is available as an online service at http://PredictionCenter.llnl.gov/local/lga. Data generated by LGA can be successfully used in a scoring function to rank the level of similarity between two structures and to allow structure classification when many protein...

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

    OpenAIRE

    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, ...

  14. The relationship between vocational interests and intelligence: Do findings generalize across different assessment methods?

    OpenAIRE

    RENÉ T. PROYER

    2007-01-01

    The aim of this study was to further explore the relationship between vocational interests and intelligence. There is some evidence in literature on the stable relationships between vocational interests and intelligence (cf. Ackerman & Heggestad, 1997). It should be noted that the majority of the previous studies have only used questionnaires for the assessment of vocational interests. Thus, it is of interest whether the results are also stable when different assessment methods are used. Ther...

  15. A General Method for Finding the Most Economical Distributed Router Architecture

    OpenAIRE

    (IBM Zurich), Lukas Kencl; (LCA), Bozidar Radunovic

    2002-01-01

    In this work we present a novel method to determine the optimal parameters of a router architecture when certain router performance constraints are given. The total financial expense, or cost, is the optimality criterion. We introduce a general, essentially distributed, router architecture model, consisting of locally or remotely located forwarding engines or processing units gathered around a switch of variable speed. Given the following constraints: number of inputs, maximum line inte...

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

    OpenAIRE

    Marinic? STAN; Petre STAN

    2013-01-01

    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

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

    Directory of Open Access Journals (Sweden)

    Marinic? 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

  18. Direct inversion in the iterative subspace-induced acceleration of the ridge method for finding transition states

    Science.gov (United States)

    Ionova, Irina V.; Carter, Emily A.

    1995-10-01

    We extend the application of the direct inversion in the iterative subspace (DIIS) technique to the ridge method for finding transition states (TS). The latter is not a quasi-Newton-type algorithm, which is the only class of geometry optimization methods that has been combined with DIIS. With this new combination, we obtain a factor of two speedup due to DIIS, similar to the DIIS-related speedup achieved in other methods including quasi-Newton geometry optimization and self-consistent field iterations. We also demonstrate that DIIS is useful even in cases where optimization is started far from the quadratic region of the TS, provided that only one previous iteration is used in the DIIS expansion. We compare the performance of the new ridge-DIIS method to that of the TS algorithm utilized in GAUSSIAN 92. We find that the computational cost of the former is similar (when both methods converge) to that of the latter. The examples considered in the paper include a novel TS found for an isomerization of a cluster of six Na atoms. Locating such a TS poses a known problem for second-derivatives-based algorithms that fail on very flat potential energy surfaces. Thus, the gradient-based ridge-DIIS method is the only TS search method that is robust, does not need second derivatives and/or an initial guess for the TS geometry, and whose performance matches or exceeds that of a second-derivatives-based algorithm.

  19. A comparison of companion matrix methods to find roots of a trigonometric polynomial

    Science.gov (United States)

    Boyd, John P.

    2013-08-01

    A trigonometric polynomial is a truncated Fourier series of the form fN(t)??j=0Naj cos(jt)+?j=1N bj sin(jt). It has been previously shown by the author that zeros of such a polynomial can be computed as the eigenvalues of a companion matrix with elements which are complex valued combinations of the Fourier coefficients, the "CCM" method. However, previous work provided no examples, so one goal of this new work is to experimentally test the CCM method. A second goal is introduce a new alternative, the elimination/Chebyshev algorithm, and experimentally compare it with the CCM scheme. The elimination/Chebyshev matrix (ECM) algorithm yields a companion matrix with real-valued elements, albeit at the price of usefulness only for real roots. The new elimination scheme first converts the trigonometric rootfinding problem to a pair of polynomial equations in the variables (c,s) where c?cos(t) and s?sin(t). The elimination method next reduces the system to a single univariate polynomial P(c). We show that this same polynomial is the resultant of the system and is also a generator of the Groebner basis with lexicographic ordering for the system. Both methods give very high numerical accuracy for real-valued roots, typically at least 11 decimal places in Matlab/IEEE 754 16 digit floating point arithmetic. The CCM algorithm is typically one or two decimal places more accurate, though these differences disappear if the roots are "Newton-polished" by a single Newton's iteration. The complex-valued matrix is accurate for complex-valued roots, too, though accuracy decreases with the magnitude of the imaginary part of the root. The cost of both methods scales as O(N3) floating point operations. In spite of intimate connections of the elimination/Chebyshev scheme to two well-established technologies for solving systems of equations, resultants and Groebner bases, and the advantages of using only real-valued arithmetic to obtain a companion matrix with real-valued elements, the ECM algorithm is noticeably inferior to the complex-valued companion matrix in simplicity, ease of programming, and accuracy.

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

    International Nuclear Information System (INIS)

    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/(? 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 to balls of non-uniform density.

  1. ALGORITHM FOR FINDING EFFECTIVE FORMS AND METHODS OF TRADE ACTIVATION AND OPTIMIZATION OF FOREIGN UKRAINE

    Directory of Open Access Journals (Sweden)

    ?.?. ??????

    2011-12-01

    Full Text Available  The Fundamental and applied problems of activation and optimization of foreign economic activity is choice of effective forms and methods of realization of external economic point-of-sale operations. In this context, on the basis of the Ukrainian legislation and economic literature, it is formulated and generalized them teoretiko-methodological essence, and also separate features which can serve as the economic instruments of activation and optimization of foreign economic activity of Ukraine are marked. Generalized methodological properties of algorithms and the schematic algorithm of search of economic instruments of activation and optimization of foreign economic activity of Ukraine is developed.

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

    Science.gov (United States)

    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.

  3. A Vision based Geometrical Method to find Fingers Positions in Real Time Hand Gesture Recognition

    Directory of Open Access Journals (Sweden)

    Ankit Chaudhary

    2012-04-01

    Full Text Available A novel method to calculate the bended finger’s angle has presented here which could be used to control the electro-mechanical robotic hand. It is assumed that the robotic hand has the human hand like joints and same number of degree of freedom as human hand. In many applications an equipment like human hand is needed, to do the same kind of operation like human do. These days it is easy to make the electro-mechanical robotic hand which has five fingers and same joint but it is not easily controllable as the human hand for accurate work. In our method the hand gesture will be interpreted for controlling the robotic hand. The angles for all the fingers will be calculated and that could be further passed to the robotic hand for controlling its finger. User would perform gesture according to the action as he wants to be done by robotic hand. Here finger positions are detected using geometric modeling of hand in the extracted image Region of interest cropping from the image made the algorithm faster.

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

    Science.gov (United States)

    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

  5. Finding disease variants in Mendelian disorders by using sequence data: methods and applications.

    Science.gov (United States)

    Ionita-Laza, Iuliana; Makarov, Vlad; Yoon, Seungtai; Raby, Benjamin; Buxbaum, Joseph; Nicolae, Dan L; Lin, Xihong

    2011-12-01

    Many sequencing studies are now underway to identify the genetic causes for both Mendelian and complex traits. Via exome-sequencing, genes harboring variants implicated in several Mendelian traits have already been identified. The underlying methodology in these studies is a multistep algorithm based on filtering variants identified in a small number of affected individuals and depends on whether they are novel (not yet seen in public resources such as dbSNP), shared among affected individuals, and other external functional information on the variants. Although intuitive, these filter-based methods are nonoptimal and do not provide any measure of statistical uncertainty. We describe here a formal statistical approach that has several distinct advantages: (1) it provides fast computation of approximate p values for individual genes, (2) it adjusts for the background variation in each gene, (3) it allows for incorporation of functional or linkage-based information, and (4) it accommodates designs based on both affected relative pairs and unrelated affected individuals. We show via simulations that the proposed approach can be used in conjunction with the existing filter-based methods to achieve a substantially better ranking of a gene relevant for disease when compared to currently used filter-based approaches, this is especially so in the presence of disease locus heterogeneity. We revisit recent studies on three Mendelian diseases and show that the proposed approach results in the implicated gene being ranked first in all studies, and approximate p values of 10(-6) for the Miller Syndrome gene, 1.0 × 10(-4) for the Freeman-Sheldon Syndrome gene, and 3.5 × 10(-5) for the Kabuki Syndrome gene. PMID:22137099

  6. Finding an optimal method for imaging lymphatic vessels of the upper limb

    International Nuclear Information System (INIS)

    Lymphoscintigraphy involves interstitial injection of radiolabelled particulate materials or radioproteins. Although several variations in the technique have been described, their place in clinical practice remains controversial. Traditional diagnostic criteria are based primarily on lymph node appearances but in situations such as breast cancer, where lymph nodes may have been excised, these criteria are of limited use. In these circumstances, lymphatic vessel morphology takes on greater importance as a clinical endpoint, so a method that gives good definition of lymphatic vessels would be useful. In patients with breast cancer, for example, such a method, used before and after lymph node resection, may assist in predicting the development of breast cancer-related lymphoedema. The aim of this study was to optimise a method for the visualisation of lymphatic vessels. Subcutaneous (sc) and intradermal (id) injection sites were compared, and technetium-99m nanocolloid, a particulate material, was compared with 99mTc-human immunoglobulin (HIG), which is a soluble macromolecule. Twelve normal volunteers were each studied on two occasions. In three subjects, id 99mTc-HIG was compared with sc 99mTc-HIG, in three id 99mTc-nanocolloid was compared with sc 99mTc-nanocolloid, in three id 99mTc-HIG was compared with id 99mTc-nanocolloid and in three sc 99mTc-HIG was compared with sc 99mTc-nanocolloid. Endpoints were quality of lymphatic vessel definition, the time after injection at which vessels were most clearly visualised, the rate constant of depot disappearance (k) and the systemic blood accumulation rate as measured by gamma camera imaging over the liver or cardiac blood pool. Excellent definition of lymphatic vessels was obtained following id injection of either radiopharmaceutical, an injection route that was clearly superior to sc. Differences between radiopharmaceuticals were less clear, although after id injection, 99mTc-HIG gave images that were marginally but significantly better than those given by 99mTc-nanocolloid. Image quality correlated inversely with time after injection at which the best image was obtained, consistent with the notion that good vessel definition was dependent on a ''narrow'' bolus width. k was approximately three times higher after id injection than after sc injection but it was not significantly different between radiopharmaceuticals for either injection route. Intradermal 99mTc-HIG gave a cardiac blood pool signal that, over the first 60 min, increased about five times faster than that with sc 99mTc-HIG, but no clear difference was observed in the rate of increase in hepatic activity between id 99mTc-nanocolloid and sc 99mTc-nanocolloid. We conclude that id injection provides rapid access of radiotracers to lymphatic vessels, which is ideal for imaging lymphatic vessel morphology. 99mTc-HIG is marginally superior to nanocolloid for this purpose and, in drainage basins from which lymph nodes have been excised, is not handicapped by a potentially inferior ability, compared with radiocolloid, to image lymph nodes. (orig.)

  7. Finding an optimal method for imaging lymphatic vessels of the upper limb

    Energy Technology Data Exchange (ETDEWEB)

    O' Mahony, Susan; Purushotham, Arnie D. [Cambridge Breast Unit, Addenbrooke' s Hospital, Cambridge (United Kingdom); Rose, Sarah L.; Chilvers, Alison J.; Ballinger, James R.; Solanki, Chandra K.; Barber, Robert W.; Peters, A. Michael [Department of Nuclear Medicine, Addenbrooke' s Hospital, Hills Road, CB2 2QQ, Cambridge (United Kingdom); Mortimer, Peter S. [Department of Medicine, St George' s Hospital, London (United Kingdom)

    2004-04-01

    Lymphoscintigraphy involves interstitial injection of radiolabelled particulate materials or radioproteins. Although several variations in the technique have been described, their place in clinical practice remains controversial. Traditional diagnostic criteria are based primarily on lymph node appearances but in situations such as breast cancer, where lymph nodes may have been excised, these criteria are of limited use. In these circumstances, lymphatic vessel morphology takes on greater importance as a clinical endpoint, so a method that gives good definition of lymphatic vessels would be useful. In patients with breast cancer, for example, such a method, used before and after lymph node resection, may assist in predicting the development of breast cancer-related lymphoedema. The aim of this study was to optimise a method for the visualisation of lymphatic vessels. Subcutaneous (sc) and intradermal (id) injection sites were compared, and technetium-99m nanocolloid, a particulate material, was compared with {sup 99m}Tc-human immunoglobulin (HIG), which is a soluble macromolecule. Twelve normal volunteers were each studied on two occasions. In three subjects, id {sup 99m}Tc-HIG was compared with sc {sup 99m}Tc-HIG, in three id {sup 99m}Tc-nanocolloid was compared with sc {sup 99m}Tc-nanocolloid, in three id {sup 99m}Tc-HIG was compared with id {sup 99m}Tc-nanocolloid and in three sc {sup 99m}Tc-HIG was compared with sc {sup 99m}Tc-nanocolloid. Endpoints were quality of lymphatic vessel definition, the time after injection at which vessels were most clearly visualised, the rate constant of depot disappearance (k) and the systemic blood accumulation rate as measured by gamma camera imaging over the liver or cardiac blood pool. Excellent definition of lymphatic vessels was obtained following id injection of either radiopharmaceutical, an injection route that was clearly superior to sc. Differences between radiopharmaceuticals were less clear, although after id injection, {sup 99m}Tc-HIG gave images that were marginally but significantly better than those given by {sup 99m}Tc-nanocolloid. Image quality correlated inversely with time after injection at which the best image was obtained, consistent with the notion that good vessel definition was dependent on a ''narrow'' bolus width. k was approximately three times higher after id injection than after sc injection but it was not significantly different between radiopharmaceuticals for either injection route. Intradermal {sup 99m}Tc-HIG gave a cardiac blood pool signal that, over the first 60 min, increased about five times faster than that with sc {sup 99m}Tc-HIG, but no clear difference was observed in the rate of increase in hepatic activity between id {sup 99m}Tc-nanocolloid and sc {sup 99m}Tc-nanocolloid. We conclude that id injection provides rapid access of radiotracers to lymphatic vessels, which is ideal for imaging lymphatic vessel morphology. {sup 99m}Tc-HIG is marginally superior to nanocolloid for this purpose and, in drainage basins from which lymph nodes have been excised, is not handicapped by a potentially inferior ability, compared with radiocolloid, to image lymph nodes. (orig.)

  8. Iterative methods for finding optimal quantum measurements under minimum-error and minimax criteria

    Science.gov (United States)

    Nakahira, Kenji; Kato, Kentaro; Usuda, Tsuyoshi Sasaki

    2015-01-01

    We investigate the problem of computing optimal quantum measurements in both minimal measuring and minimax strategies. A Belavkin weighted square-root measurement (BWSRM) with appropriate weights can represent the measurement that maximizes the correct probability for any given prior probabilities of quantum states. Using this fact, we propose methods for computing optimal solutions by optimizing the weights of the BWSRM. First, we explain the conditions for the BWSRM to be optimal. In particular, we argue that if a BWSRM with certain weights is a minimax measurement, then the minimax probabilities can be immediately obtained. Next, we propose an extension of the iterative algorithm developed by Ježek et al. [Phys. Rev. A 65, 060301 (2002), 10.1103/PhysRevA.65.060301] for maximizing the correct probability. We prove that, for a linearly independent pure state set, Ježek et al.'s algorithm converges to an optimal measurement. We also propose an iterative algorithm for a minimax solution and prove that, for a pure state set, our algorithm monotonically decreases the difference between estimated and true minimax values. Finally the performance of our algorithms is evaluated through numerical experiments.

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

    Directory of Open Access Journals (Sweden)

    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.

  10. The Pade approximant method for finding the Hilbert-Schmidt eigenvalues and eigenfunctions in two- and three-body problems

    International Nuclear Information System (INIS)

    An approach is proposed which makes it possible to obtain the Hilbert-Schmidt (or Sturm-Liouville) eigenvalue and eigenfunctions for two-or three-body systems over the entire domain of analyticity of these functions in energy on the basis of calculations of bound states only. It is shown how this method may be used to find the two- and three-body resonances and the near-threshold states. (orig.)

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

    OpenAIRE

    Shestopaloff, Yuri K.

    2015-01-01

    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 influenc...

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  14. Localization Accuracy Improved Methods Based on Adaptive Weighted Centroid Localization Algorithm in Wireless Sensor Networks

    OpenAIRE

    Kee-Wook Rim; Kyung-Yong Chung; Jung-Hyun Lee2; Jun-Ling Ma; Chang-Woo Song

    2010-01-01

    Generally, see Localization of nodes is a key technology for application of wireless sensor network. Having a GPS receiver on every sensor node is costly. In the past, several approaches, including range-based and range-free, have been proposed to calculate positions for randomly deployed sensor nodes. Most of them use some special nodes, called anchor nodes, which are assumed to know their own locations. Other sensors compute their locations based on the information provided by these anchor ...

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

    Directory of Open Access Journals (Sweden)

    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

  16. Shack-Hartmann wavefront sensing with elongated sodium laser beacons: centroiding versus matched filtering

    Science.gov (United States)

    Gilles, Luc; Ellerbroek, Brent

    2006-09-01

    We describe modeling and simulation results for the Thirty Meter Telescope on the degradation of sodium laser guide star Shack-Hartmann wavefront sensor measurement accuracy that will occur due to the spatial structure and temporal variations of the mesospheric sodium layer. By using a contiguous set of lidar measurements of the sodium profile, the performance of a standard centroid and of a more refined noise-optimal matched filter spot position estimation algorithm is analyzed and compared for a nominal mean signal level equal to 1000 photodetected electrons per subaperture per integration time, as a function of subaperture to laser launch telescope distance and CCD pixel readout noise. Both algorithms are compared in terms of their rms spot position estimation error due to noise, their associated wavefront error when implemented on the Thirty Meter Telescope facility adaptive optics system, their linear dynamic range, and their bias when detuned from the current sodium profile.

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

    Directory of Open Access Journals (Sweden)

    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.

  18. Random Centroid Optimization of Phyosphatidylglycerol Stablized Lutein-Enriched Oil-In-Water Emulsions at Acidic pH

    Science.gov (United States)

    Lutein has been identified by various studies as a dietary compound that may help delay the onset of macular degeneration. Random centroid optimization was applied to design, prepare, and characterize lutein-enriched oil-in-water (o/w) emulsions containing corn oil (15-25%), whey proteins (1.5-3.5%...

  19. A Novel Systematic Error Compensation Algorithm Based on Least Squares Support Vector Regression for Star Sensor Image Centroid Estimation

    Directory of Open Access Journals (Sweden)

    Jingyan Song

    2011-07-01

    Full Text Available The star centroid estimation is the most important operation, which directly affects the precision of attitude determination for star sensors. This paper presents a theoretical study of the systematic error introduced by the star centroid estimation algorithm. The systematic error is analyzed through a frequency domain approach and numerical simulations. It is shown that the systematic error consists of the approximation error and truncation error which resulted from the discretization approximation and sampling window limitations, respectively. A criterion for choosing the size of the sampling window to reduce the truncation error is given in this paper. The systematic error can be evaluated as a function of the actual star centroid positions under different Gaussian widths of star intensity distribution. In order to eliminate the systematic error, a novel compensation algorithm based on the least squares support vector regression (LSSVR with Radial Basis Function (RBF kernel is proposed. Simulation results show that when the compensation algorithm is applied to the 5-pixel star sampling window, the accuracy of star centroid estimation is improved from 0.06 to 6 × 10?5 pixels.

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

    Science.gov (United States)

    Laurent, Louise C; Abdel-Mageed, Asim B; Adelson, P David; Arango, Jorge; Balaj, Leonora; Breakefield, Xandra; Carlson, Elizabeth; Carter, Bob S; Majem, Blanca; Chen, Clark C; Cocucci, Emanuele; Danielson, Kirsty; Courtright, Amanda; Das, Saumya; Abd Elmageed, Zakaria Y; Enderle, Daniel; Ezrin, Alan; Ferrer, Marc; Freedman, Jane; Galas, David; Gandhi, Roopali; Huentelman, Matthew J; Van Keuren-Jensen, Kendall; Kalani, Yashar; Kim, Yong; Krichevsky, Anna M; Lai, Charles; Lal-Nag, Madhu; Laurent, Clara D; Leonardo, Trevor; Li, Feng; Malenica, Ivana; Mondal, Debasis; Nejad, Parham; Patel, Tushar; Raffai, Robert L; Rubio, Renee; Skog, Johan; Spetzler, Robert; Sun, Jie; Tanriverdi, Kahraman; Vickers, Kasey; Wang, Liang; Wang, Yaoyu; Wei, Zhiyun; Weiner, Howard L; Wong, David; Yan, Irene K; Yeri, Ashish; Gould, Stephen

    2015-01-01

    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. PMID:26320937

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

    Directory of Open Access Journals (Sweden)

    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.

  2. Kinetic and thermodynamic parameters of biodiesel oxidation with synthetic antioxidants: simplex centroid mixture design

    Scientific Electronic Library Online (English)

    Dionisio, Borsato; Diego, Galvan; Jaqueline L., Pereira; Juliane R., Orives; Karina G., Angilelli; Rodolfo L., Coppo.

    2014-11-01

    Full Text Available A influência da temperatura sobre a oxidação de biodiesel foi avaliada pelos parâmetros cinéticos e termodinâmicos do biocombustível de óleo de soja e gordura suína com antioxidantes sintéticos: 3-terc-butil-4-hidroxianisol (BHA), 3,5-di-terc-butil-hidroxitolueno (BHT), 2-terc-butil-hidroquinona (TB [...] HQ) e galato de propila (PG), de acordo com delineamento de mistura simplex-centróide. Os parâmetros cinéticos foram determinados considerando-se reação de primeira ordem e aplicando a equação de Arrhenius. A adição de antioxidantes promoveu o aumento da energia de ativação (Ea), sendo TBHQ e PG os mais eficientes, apresentando efeito sinérgico. BHT e BHA foram os menos eficientes, assim como suas misturas. Os parâmetros termodinâmicos de ativação, avaliados pela equação de Eyring, não indicaram processos espontâneos (?G‡ > 0) com valores de ?H‡ positivos, e ?S‡ positivos e negativos. O delineamento simplex-centróide indicou valor otimizado de 174,46 kJ mol-1 para a mistura contendo 33,33 e 66,67% de TBHQ e PG, respectivamente. Abstract in english Temperature's influence on biodiesel oxidation was evaluated by kinetic and thermodynamic data in biofuel from soybean oil and lard with synthetic antioxidants: butylatedhydroxyanisol (BHA), butylatedhydroxytoluene (BHT), tert-butylhydroquinone (TBHQ), and propylgallate (PG) by simplex centroid mixt [...] ure design. The kinetic parameters ware obtained by Arrhenius equation and showed that addition of antioxidants in all tests increased activation energy (Ea) and that TBHQ and PG were more efficient and presented synergistic effect. BHT and BHA were the least efficient, as well as their mixtures. The thermodynamic activation parameters of the reactions, evaluated by the Eyring equation and based on the theory of the activated complex (ACT), indicated no spontaneous processes (?G‡ > 0) with positive ?H‡ values and positive and negative ?S‡ values. The application of simplex centroid mixture design, using Ea as response, showed the optimised value of 174.46 kJ mol-1 for a mixture containing 33.33 and 66.67% of TBHQ and PG, respectively.

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

    Directory of Open Access Journals (Sweden)

    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 to interrogate each dataset more fully. Not only does this enhance the robustness of the study, it may lead to different conclusions from those that would have been drawn through relying on one method alone and demonstrates the value of collecting both types of data within a single study. More widespread use of mixed methods in trials of complex interventions is likely to enhance the overall quality of the evidence base.

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

    Directory of Open Access Journals (Sweden)

    Xiong Yu

    2011-09-01

    Full Text Available 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 were considered in the RCO program. Three sets of optimum proposed factor values were obtained corresponding to three extraction targets respectively. The set of optimum proposed factor values for polyphenol extraction given was chosen in further experiments as following: liquid and solid ratio (v/w 8, ethanol 67.3% (v/v, initial pH 1.75, temperature 55 °C for 4 h and extraction repeated for 4 times. The Wuweizi polyphenol extract (WPE was obtained with a yield of 16.37 mg/g and composition of polyphenols 1.847 mg/g, anthocyanins 0.179 mg/g, sugar 9.573 mg/g and protein 0.327 mg/g. The WPE demonstrated high scavenging activities against DPPH radicals.

  5. A phylogenetic Gibbs sampler that yields centroid solutions of cis-regulatory sites

    Energy Technology Data Exchange (ETDEWEB)

    Newberg, Lee A.; Thompson, William A.; Conlan, Sean; Smith, Thomas M.; McCue, Lee Ann; Lawrence, Charles E.

    2007-07-15

    Identification of functionally conserved regulatory elements in sequence data from closely related organisms is becoming feasible, due to the rapid growth of public sequence databases. Closely related organisms are most likely to have common regulatory motifs, however the recent speciation of such organisms results in the high degree of correlation in their genome sequences, confounding the detection of functional elements. Additionally, alignment algorithms that use optimization techniques are limited to the detection of a single alignment that may not be representative. Comparative-genomics studies must be able to address the phylogenetic correlation in the data and efficiently explore the alignment space, in order to make specific and biologically relevant predictions. Results: We describe here a Gibbs sampler that employs a full phylogenetic model and reports an ensemble centroid solution. We describe regulatory motif detection using both simulated and real data, and demonstrate that this approach achieves improved specificity, sensitivity, and positive predictive value over non-phylogenetic algorithms, and over phylogenetic algorithms that report a maximum likelihood solution.

  6. Collective centroid oscillations as an emittance preservation diagnostic in linear collider linacs

    International Nuclear Information System (INIS)

    Transverse bunch centroid oscillations, induced at operating beam currents at which transverse wakefields are substantial, and observed at Beam Position Monitors, are sensitive to the actual magnetic focusing, energy gain, and rf phase profiles in a linac, and are insensitive to misalignments and jitter sources. In the pulse stealing set-up implemented at the SLC, they thus allow the frequent monitoring of the stability of the in-place emittance growth inhibiting or mitigating measures--primarily the energy scaled magnetic lattice and the rf phases necessary for BNS damping--independent of the actual emittance growth as driven by misalignments and jitter. The authors have developed a physically based analysis technique to meaningfully reduce the data. Oscillation beta-beating is a primary indicator of beam energy errors; shifts in the invariant amplitude reflect differential internal motion along the longitudinally extended bunch and thus are a sensitive indicator of the real rf phases in the machine; shifts in betatron phase advance contain corroborative information sensitive to both effects

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

    Directory of Open Access Journals (Sweden)

    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 considerations meant that 26 practices in Sandwell could be randomised, including about 6,250 patients at high risk of cardiovascular disease. This gives sufficient power for evaluation. Discussion It is possible to design a stepped wedge randomised controlled trial using routine data to determine the primary outcome to evaluate implementation of a cardiovascular prevention programme.

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

    International Nuclear Information System (INIS)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Ronald C. Davidson and B. Grant Logan

    2011-07-19

    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.

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

    International Nuclear Information System (INIS)

    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

  11. Computational Method and a Numerical Algorithm for Finding the Optimal Control Policy for a Partially Observable System

    Science.gov (United States)

    Makis, Viliam; Kim, Michael Jong; Jiang, Rui

    2009-09-01

    In this paper a computational method and numerical algorithm is developed for finding the optimal control policy for a partially observable system subject to random failure. The condition of the system is modeled by an unobservable continuous-time homogeneous Markov chain. Multivariate data stochastically related to the system state is collected at equidistant sampling times. The system is controlled by a multivariate Bayesian control chart, i.e. full inspection followed by maintenance is performed when the posterior probability that the system is in the warning state exceeds a control limit. A statistical constraint is considered which bounds the probability of a true alarm given by the control chart. The objective is to minimize the long-run expected average cost per unit time by determining the optimal values of the control limit and sampling interval subject to the statistical constraint. The stochastic evolution of the posterior probability process is analyzed and computational algorithm is developed in the semi-Markov decision process framework. Numerical examples are provided which illustrate the effect of the statistical constraint and the performance of the Bayesian control chart is compared with the traditional multivariate ?2 control chart.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

    Abdoljabbar Asadi; Azad Shojaei; Salar Saeidi; Salah Karimi; Ebad Karimi

    2012-01-01

    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...

  14. 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

    CERN Document Server

    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 ...

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

    Directory of Open Access Journals (Sweden)

    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 Species Concept of Seifert (2014. The taxonomic description and a differential diagnosis of T. crasecundus sp. n. are given.

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

    Science.gov (United States)

    Chin, Alexander W.; Herrera, Claudia Y.; Spivey, Natalie D.; Fladung, William A.; Cloutier, David

    2015-01-01

    The mass properties of an aerospace vehicle are required by multiple disciplines in the analysis and prediction of flight behavior. Pendulum oscillation methods have been developed and employed for almost a century as a means to measure mass properties. However, these oscillation methods are costly, time consuming, and risky. The NASA Armstrong Flight Research Center has been investigating the Dynamic Inertia Measurement, or DIM method as a possible alternative to oscillation methods. The DIM method uses ground test techniques that are already applied to aerospace vehicles when conducting modal surveys. Ground vibration tests would require minimal additional instrumentation and time to apply the DIM method. The DIM method has been validated on smaller test articles, but has not yet been fully proven on large aerospace vehicles.

  17. A genetic-algorithm-based method to find unitary transformations for any desired quantum computation and application to a one-bit oracle decision problem

    Science.gov (United States)

    Bang, Jeongho; Yoo, Seokwon

    2014-12-01

    We propose a genetic-algorithm-based method to find the unitary transformations for any desired quantum computation. We formulate a simple genetic algorithm by introducing the "genetic parameter vector" of the unitary transformations to be found. In the genetic algorithm process, all components of the genetic parameter vectors are supposed to evolve to the solution parameters of the unitary transformations. We apply our method to find the optimal unitary transformations and to generalize the corresponding quantum algorithms for a realistic problem, the one-bit oracle decision problem, or the often-called Deutsch problem. By numerical simulations, we can faithfully find the appropriate unitary transformations to solve the problem by using our method. We analyze the quantum algorithms identified by the found unitary transformations and generalize the variant models of the original Deutsch's algorithm.

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

    Science.gov (United States)

    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…

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

    OpenAIRE

    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...

  20. On finding an obstacle embedded in the rough background medium via the enclosure method in the time domain

    Science.gov (United States)

    Ikehata, Masaru

    2015-08-01

    A mathematical method for through-wall imaging via wave phenomena in the time domain is introduced. The method makes use of a single reflected wave over a finite time interval and gives us a criterion whether a penetrable obstacle exists or not in a general rough background medium. Moreover, if the obstacle exists, the lower and upper estimates of the distance between the obstacle and the center point of the support of the initial data are given. As an evidence of the potential of the method two applications are also given.

  1. Diagnostic methods in finding out the causes of infertility, results of HSG examination and laparoscopy in infertile women examined at the Gynecological Ward of the City Hospital

    International Nuclear Information System (INIS)

    The paper presents diagnostic methods and the results of hysterosalpingography (HSG) and laparoscopy examination, with special attention being drawn to the usefulness of these methods in finding out the causes of infertility. 51 patients with primary and second infertility were examined. HSG and laparoscopy make it possible to diagnose correctly the cause of infertility. They also enable adequate and early classification of patients for further diagnosis and treatment at highly specialized centers dealing with the problems of infertility. (author)

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

    Science.gov (United States)

    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 75wt% 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

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

    Science.gov (United States)

    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. Transference, relationship and the analyst as object: Findings from the North American Comparative Clinical Methods Working Party.

    Science.gov (United States)

    Rudden, Marie G; Bronstein, Abbot

    2015-06-01

    Data from the North American Comparative Clinical Methods (CCM) Working Party a is used to 1) explore how psychoanalysts in North America conceive and address the transference and the relationship between analyst-analysand and 2) to study what kinds of 'objects' psychoanalysts become, explicitly and implicitly, within psychoanalytic treatments. The North American CCM Working Party closely studied 17 clinical cases presented by North American psychoanalysts across the spectrum of analytic schools at their meetings. We found that the 17 analysts fell into three different groupings according to the internal consistency of their method and their approaches to transference, relationship and analyst-as -object. We also found that analysts' individual work, while heavily influenced by their schools of thought, also involved unique interpretations of their particular paradigms. PMID:26173885

  5. Perturbed damped pendulum: finding periodic solutions via averaging method / Perturbações do pêndulo amortecido: encontrando soluções periódicas via método averaging

    Scientific Electronic Library Online (English)

    Douglas D., Novaes.

    2013-03-01

    Full Text Available Utilizando o modelo do pêndulo amortecido, introduzimos o método "averaging" no estudo de soluções periódicas de sistemas dinâmicos com pequenas perturbações não autónomas. Considerando perturbações do sistema do pêndulo amortecido, fornecemos condições suficientes para a existência de soluções peri [...] ódicas de pequena amplitude. O método "averaging" fornece uma ferramenta útil no estudo de sistemas dinâmicos e é acessível a estudantes de pós-graduação. Abstract in english Using the damped pendulum model we introduce the averaging method to study the periodic solutions of dynamical systems with small non-autonomous perturbation. We provide sufficient conditions for the existence of periodic solutions with small amplitude of the non-linear perturbed damped pendulum. Th [...] e averaging method provides a useful means to study dynamical systems, accessible to Master and PhD students.

  6. Use of a Novel Method to Find Substrates of Protein Kinase C Delta Identifies M2 Pyruvate Kinase

    OpenAIRE

    Siwko, Stefan; Mochly-Rosen, Daria

    2007-01-01

    Protein kinase C (PKC) family members have been implicated in numerous cellular processes. However, identifying the substrates of each PKC isozyme remains a challenge. Here, we describe a method using two dimensional (2-D) isoelectric focusing gel electrophoresis to identify substrates of delta PKC (?PKC) in MCF-7 breast carcinoma cells. We show that M2 pyruvate kinase is a substrate of ?PKC, and further characterize the interaction between M2 pyruvate kinase and ?PKC in MCF-7 cells by immuno...

  7. Consumer Attitudes and Perceptions on mHealth Privacy and Security: Findings From a Mixed-Methods Study.

    Science.gov (United States)

    Atienza, Audie A; Zarcadoolas, Christina; Vaughon, Wendy; Hughes, Penelope; Patel, Vaishali; Chou, Wen-Ying Sylvia; Pritts, Joy

    2015-01-01

    This study examined consumers' attitudes and perceptions regarding mobile health (mHealth) technology use in health care. Twenty-four focus groups with 256 participants were conducted in 5 geographically diverse locations. Participants were also diverse in age, education, race/ethnicity, gender, and rural versus urban settings. Several key themes emerged from the focus groups. Findings suggest that consumer attitudes regarding mHealth privacy/security are highly contextualized, with concerns depending on the type of information being communicated, where and when the information is being accessed, who is accessing or seeing the information, and for what reasons. Consumers frequently considered the tradeoffs between the privacy/security of using mHealth technologies and the potential benefits. Having control over mHealth privacy/security features and trust in providers were important issues for consumers. Overall, this study found significant diversity in attitudes regarding mHealth privacy/security both within and between traditional demographic groups. Thus, to address consumers' concerns regarding mHealth privacy and security, a one-size-fits-all approach may not be adequate. Health care providers and technology developers should consider tailoring mHealth technology according to how various types of information are communicated in the health care setting, as well as according to the comfort, skills, and concerns individuals may have with mHealth technology. PMID:25868685

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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

  10. A New Method to Find the Fractional Slot Windings Structures from a Distributed Slot Windings Permanent Magnet Synchronous Machine and Comparative Study for a HEV Application

    OpenAIRE

    Nguyen, Phi Hung; Hoang, Emmanuel; Gabsi, Mohamed; Lécrivain, Michel

    2010-01-01

    This paper presents a distributed slot permanent magnet synchronous machine (PMSM). It's a machine characterized by a distributed windings stator and a surface mounted PM rotor. First, a basic PMSM called “classical” has been studied. Then, we have developed a new method to find the others machines with the same winding distribution on stator but with different rotor pole number so that we have obtained PMSMs with fractional slot windings. From the fractional slot structures developed, we hav...

  11. Finding the transition state of quasi-barrierless reactions by a growing string method for newton trajectories: application to the dissociation of methylenecyclopropene and cyclopropane.

    Science.gov (United States)

    Quapp, Wolfgang; Kraka, Elfi; Cremer, Dieter

    2007-11-01

    A method for finding a transition state (TS) between a reactant minimum and a quasi-flat, high dissociation plateau on the potential energy surface is described. The method is based on the search of a growing string (GS) along reaction pathways defined by different Newton trajectories (NT). Searches with the GS-NT method always make it possible to identify the TS region because monotonically increasing NTs cross at the TS or, if not monotonically increasing, possess turning points that are located in the TS region. The GS-NT method is applied to quasi-barrierless and truly barrierless chemical reactions. Examples are the dissociation of methylenecyclopropene to acetylene and vinylidene, for which a small barrier far out in the exit channel is found, and the cycloaddition of singlet methylene and ethene, which is barrierless for a broad reaction channel with Cs-symmetry reminiscent of a mountain cirque formed by a glacier. PMID:17705351

  12. The Tourette International Collaborative Genetics (TIC Genetics) study, finding the genes causing Tourette syndrome : objectives and methods

    DEFF Research Database (Denmark)

    Dietrich, Andrea; Fernandez, Thomas V

    2015-01-01

    Tourette syndrome (TS) is a neuropsychiatric disorder characterized by recurrent motor and vocal tics, often accompanied by obsessive-compulsive disorder and/or attention-deficit/hyperactivity disorder. While the evidence for a genetic contribution is strong, its exact nature has yet to be clarified fully. There is now mounting evidence that the genetic risks for TS include both common and rare variants and may involve complex multigenic inheritance or, in rare cases, a single major gene. Based on recent progress in many other common disorders with apparently similar genetic architectures, it is clear that large patient cohorts and open-access repositories will be essential to further advance the field. To that end, the large multicenter Tourette International Collaborative Genetics (TIC Genetics) study was established. The goal of the TIC Genetics study is to undertake a comprehensive gene discovery effort, focusing both on familial genetic variants with large effects within multiply affected pedigrees and on de novo mutations ascertained through the analysis of apparently simplex parent-child trios with non-familial tics. The clinical data and biomaterials (DNA, transformed cell lines, RNA) are part of a sharing repository located within the National Institute for Mental Health Center for Collaborative Genomics Research on Mental Disorders, USA, and will be made available to the broad scientific community. This resource will ultimately facilitate better understanding of the pathophysiology of TS and related disorders and the development of novel therapies. Here, we describe the objectives and methods of the TIC Genetics study as a reference for future studies from our group and to facilitate collaboration between genetics consortia in the field of TS.

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

    Indian Academy of Sciences (India)

    Yun Hua; Feng Qi

    2014-11-01

    In this paper, the authors find the best numbers and such that $\\overline{C}(\\alpha a+ (1 - \\alpha)b$, $\\alpha b + (1 - \\alpha)a) \\lt T (a, b) \\lt \\overline{C} (\\beta a + (1 - \\beta)b, \\beta b + (1 - \\beta)a)$ for all , $b \\gt 0$ with $a \

  14. Sylfiden findes

    DEFF Research Database (Denmark)

    Christensen, Anne Middelboe

    2008-01-01

    Sylfiden findes. Men hvordan kan sylfiden findes - og bare være en drøm? Denne ’svævebog’ fortolker længslen i Bournonvilles internationale ballethit - gennem nye fotos af katastrofefotografen Jan Grarup samt fortolkende svæveessays, meddigtende flakserier, en sylfidescrapbog med anmeldelser af balletdansere i hovedpartierne i Sylfiden fra 1836 til 2008, et sylfideleksikon og sylfideord for børn. En videnskabelig bog, formidlet for både ballethistorikeren, balletelskeren, balletbegynderen og rom...

  15. A comparison of three clustering methods for finding subgroups in MRI, SMS or clinical data : SPSS TwoStep Cluster analysis, Latent Gold and SNOB

    DEFF Research Database (Denmark)

    Kent, Peter; Jensen, Rikke K

    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, Latent Gold LCA and SNOB LCA). METHODS: The performance of these three methods was compared: (i) quantitatively using the number of subgroups detected, the classification probability of individuals into subgroups, the reproducibility of results, and (ii) qualitatively using subjective judgments about 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 only pain intensity data collected for 52 weeks by text (SMS) messaging (n = 1,121 people), and the last dataset contained a range of clinical variables measured in low back pain patients (n = 543 people). Four artificial datasets (n = 1,000 each) containing subgroups of varying complexity were also analysed testing the ability of these clustering methods to detect subgroups and correctly classify individuals when subgroup membership was known. RESULTS: The results from the real clinical datasets indicated that the number of subgroups detected varied, the certainty of classifying individuals into those subgroups varied, the findings had perfect reproducibility, some programs were easier to use and the interpretability of the presentation of their findings also varied. The results from the artificial datasets indicated that all three clustering methods showed a near-perfect ability to detect known subgroups and correctly classify individuals into those subgroups. CONCLUSIONS: Our subjective judgement was that Latent Gold offered the best balance of sensitivity to subgroups, ease of use and presentation of results with these datasets but we recognise that different clustering methods may suit other types of data and clinical research questions.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    Fleming, Kevin; Zschau, Jochen; Gasparini, Paolo

    2014-05-01

    Recent major natural disasters, such as the 2011 T?hoku 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 project: Naples, Cologne, and the French West Indies. In addition, a software platform, the MATRIX-Common IT sYstem (MATRIX-CITY), was developed to allow the evaluation of characteristic multi-hazard and risk scenarios in comparison to single-type analyses. This presentation therefore outlines the more significant outcomes of the project, in particular those dealing with the harmonization of single-type hazards, cascade event analysis, time-dependent vulnerability changes and the response of the disaster management community to the MATRIX point of view.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

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

    International Nuclear Information System (INIS)

    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.)

  20. TEST CASE GENERATION BASED ON ADAPTIVE RANDOM BORDER CENTROIDAL VORONOI TESSELLATION

    OpenAIRE

    R.Charan; Kanagaraj

    2014-01-01

    Random testing is a black box testing approach where programs are tested by generating random, independent inputs and also tested by choosing an arbitrary subset of all possible input values. Random testing is low cost and straightforward but its effectiveness is not satisfactory and it doesn’t cover the test cases properly. To increase the effectiveness of Random Testing, researchers have developed Adaptive Random Testing and Quasi-Random Testing methods which attempt to maximize th...

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

    OpenAIRE

    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

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

    Science.gov (United States)

    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.

  3. Image motion compensation by area correlation and centroid tracking of solar surface features

    Science.gov (United States)

    Nein, M. E.; Mcintosh, W. R.; Cumings, N. P.

    1983-01-01

    An experimental solar correlation tracker was tested and evaluated on a ground-based solar magnetograph. Using sunspots as fixed targets, tracking error signals were derived by which the telescope image was stabilized against wind induced perturbations. Two methods of stabilization were investigated; mechanical stabilization of the image by controlled two-axes motion of an active optical element in the telescope beam, and electronic stabilization by biasing of the electron scan in the recording camera. Both approaches have demonstrated telescope stability of about 0.6 arc sec under random perturbations which can cause the unstabilized image to move up to 120 arc sec at frequencies up to 30 Hz.

  4. Finding Sliesthorp?

    DEFF Research Database (Denmark)

    Dobat, Andres S.

    2015-01-01

    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 end of the 10th century. The site may be identical with the mystical Sliesthorp, which is mentioned in the earliest historical records as the power?centre of the first Danish kings in this disputed bor...

  5. Factors affecting uncertainty in lung nodule volume estimation with CT: comparisons of findings from two estimation methods in a phantom study

    Science.gov (United States)

    Li, Qin; Gavrielides, Marios A.; Zeng, Rongping; Myers, Kyle J.; Sahiner, Berkman; Petrick, Nicholas

    2015-03-01

    This work aimed to compare two different types of volume estimation methods (a model-based and a segmentationbased method) in terms of identifying factors affecting measurement uncertainty. Twenty-nine synthetic nodules with varying size, radiodensity, and shape were placed in an anthropomorphic thoracic phantom and scanned with a 16- detector row CT scanner. Ten repeat scans were acquired using three exposures and two slice collimations, and were reconstructed with varying slice thicknesses. Nodule volumes were estimated from the reconstructed data using a matched-filter and a segmentation approach. Log transformed volumes were used to obtain measurement error with truth obtained through micro-CT. ANOVA and multiple linear regression were applied to measurement error to identify significant factors affecting volume estimation for each method. Root mean square of measurement errors (RMSE) for meaningful subgroups, repeatability coefficients (RC) for different imaging protocols, and reproducibility coefficients (RDC) for thin and thick collimation conditions were evaluated. Results showed that for both methods, nodule size, shape and slice thickness were significant factors. Collimation was significant for the matched-filter method. RMSEs for matched-filter measurements were in general smaller than segmentation. To achieve RMSE on the order of 15% or less for {5, 8, 9, 10mm} nodules, the corresponding maximum allowable slice thicknesses were {3, 5, 5, 5mm} for the matched-filter and {0.8, 3, 3, 3mm} for the segmentation method. RCs showed similar patterns for both methods, increasing with slice thickness. For 8-10mm nodules, the measurements were highly repeatable provided the slice thickness was ?3mm, regardless of method and across varying acquisition conditions. RDCs were lower for thin collimation than thick collimation protocols. While RDC of matched filter volume estimation results was always lower than segmentation results, for 8-10mm nodules with thin collimation protocols, the measurements for both approaches were highly reproducible (RDC on the order of 15% or less). These findings are valuable for validating lung nodule volume as a quantitative imaging biomarker.

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

    International Nuclear Information System (INIS)

    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.)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  8. Plotting of liquidus surface in the system In - InP - GaAs - InAs using simplex-centroidal planning

    International Nuclear Information System (INIS)

    Liquidus surface in the In-InP-GaAs-InAs system is plotted using simplex-centroidal planning. The analysis of the results obtained permitted to state that growth of indium phosphide concentration increases liquidus temperature in quasiternary cross section of the system with constant indium content, increase of indium arsenide content gives the inverse result, while change of gallium arsenide concentration does not result in essential change of liquidus temperature (at constant concentration ratio of the other two compounds)

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

    International Nuclear Information System (INIS)

    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 with nonoperative methods. The result of our new method is acceptable because good evaluations were obtained in 70% of hips 5.4 years after reduction by our new method alone. (author)

  10. Forecasting Method for Grouped Time Series with the Use of k-Means Algorithm

    OpenAIRE

    Astakhova, N. N.; Demidova, L. A.; Nikulchev, E. V.

    2015-01-01

    The paper is focused on the forecasting method for time series groups with the use of algorithms for cluster analysis. $K$-means algorithm is suggested to be a basic one for clustering. The coordinates of the centers of clusters have been put in correspondence with summarizing time series data the centroids of the clusters. A description of time series, the centroids of the clusters, is implemented with the use of forecasting models. They are based on strict binary trees and...

  11. Quality by Design approach in the development of a solvent-modified micellar electrokinetic chromatography method: finding the design space for the determination of amitriptyline and its impurities.

    Science.gov (United States)

    Furlanetto, S; Orlandini, S; Pasquini, B; Del Bubba, M; Pinzauti, S

    2013-11-13

    A solvent-modified micellar electrokinetic chromatography method was set up for the simultaneous determination of the tricyclic antidepressant amitriptyline (AMI) and its main impurities. The method was developed following Quality by Design (QbD) principles according to ICH Guideline Q8(R2). QbD approach made it possible to find the design space (DS), where quality was assured. After a scouting phase, aimed at selecting a suitable capillary electrophoresis pseudostationary phase, risk assessment tools were employed to define the critical process parameters (CPPs) to be considered in a screening phase (applied voltage, concentration and pH of the background electrolyte, concentration of the surfactant sodium dodecyl sulphate, of the cosurfactant n-butanol and of the organic modifiers acetonitrile and urea). The effects of the seven selected CPPs on critical quality attributes (CQAs), namely resolution values between critical peak pairs and analysis time, were investigated throughout the knowledge space by means of a symmetric screening matrix. Response surface study was then carried out on four selected CPPs by applying a Doehlert Design. Monte-Carlo simulations were performed in order to estimate the probability of meeting the desired specifications on CQAs, and thus to define the DS by means of a risk of failure map. Additional points at the edges of the DS were tested in order to verify the requirements for CQAs to be fulfilled. A control strategy was implemented by defining system suitability tests. The developed method was validated following ICH Guideline Q2(R1), including robustness assessment by Plackett-Burman design, and was applied to the analysis of real samples of amitriptyline coated tablets. PMID:24176512

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

    Science.gov (United States)

    Malhotra, Shelly; Koeut, Pichenda; Thai, Sopheak; Khun, Kim Eam; Colebunders, Robert; Lynen, Lut

    2015-01-01

    Background 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. Methods 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. Results 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. Conclusions 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 to care in marginalised communities. PMID:26222545

  13. Subtropical Real Root Finding

    OpenAIRE

    Sturm, Thomas

    2015-01-01

    We describe a new incomplete but terminating method for real root finding for large multivariate polynomials. We take an abstract view of the polynomial as the set of exponent vectors associated with sign information on the coefficients. Then we employ linear programming to heuristically find roots. There is a specialized variant for roots with exclusively positive coordinates, which is of considerable interest for applications in chemistry and systems biology. An implementa...

  14. Feasibility, acceptability, and effects of gentle Hatha yoga for women with major depression: findings from a randomized controlled mixed-methods study.

    Science.gov (United States)

    Kinser, Patricia Anne; Bourguignon, Cheryl; Whaley, Diane; Hauenstein, Emily; Taylor, Ann Gill

    2013-06-01

    Major depressive disorder (MDD) is a common, debilitating chronic condition in the United States and worldwide. Particularly in women, depressive symptoms are often accompanied by high levels of stress and ruminations, or repetitive self-critical negative thinking. There is a research and clinical imperative to evaluate complementary therapies that are acceptable and feasible for women with depression and that target specific aspects of depression in women, such as ruminations. To begin to address this need, we conducted a randomized, controlled, mixed-methods community-based study comparing an 8-week yoga intervention with an attention-control activity in 27 women with MDD. After controlling for baseline stress, there was a decrease in depression over time in both the yoga group and the attention-control group, with the yoga group having a unique trend in decreased ruminations. Participants in the yoga group reported experiencing increased connectedness and gaining a coping strategy through yoga. The findings provide support for future large scale research to explore the effects of yoga for depressed women and the unique role of yoga in decreasing rumination. PMID:23706890

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

    Science.gov (United States)

    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

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

    International Nuclear Information System (INIS)

    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

  17. Method of particle trajectory recognition in particle flows of high particle concentration using a candidate trajectory tree process with variable search areas

    Science.gov (United States)

    Shaffer, Franklin D.

    2013-03-12

    The application relates to particle trajectory recognition from a Centroid Population comprised of Centroids having an (x, y, t) or (x, y, f) coordinate. The method is applicable to visualization and measurement of particle flow fields of high particle. In one embodiment, the centroids are generated from particle images recorded on camera frames. The application encompasses digital computer systems and distribution mediums implementing the method disclosed and is particularly applicable to recognizing trajectories of particles in particle flows of high particle concentration. The method accomplishes trajectory recognition by forming Candidate Trajectory Trees and repeated searches at varying Search Velocities, such that initial search areas are set to a minimum size in order to recognize only the slowest, least accelerating particles which produce higher local concentrations. When a trajectory is recognized, the centroids in that trajectory are removed from consideration in future searches.

  18. Contrasting RCC, RVU, and ABC for managed care decisions. A case study compares three widely used costing methods and finds one superior.

    Science.gov (United States)

    West, T D; Balas, E A; West, D A

    1996-08-01

    To obtain cost data needed to improve managed care decisions and negotiate profitable capitation contracts, most healthcare provider organizations use one of three costing methods: the ratio-of-costs-to-charges method, the relative value unit method, or the activity-based costing method. Although the ratio-of-costs to charges is used by a majority of provider organizations, a case study that applied these three methods in a renal dialysis clinic found that the activity-based costing method provided the most accurate cost data. By using this costing method, healthcare financial managers can obtain the data needed to make optimal decisions regarding resource allocation and cost containment, thus assuring the longterm financial viability of their organizations. PMID:10158925

  19. Methods of Pest Control and Direct Yield Loss Assessment of Country Bean (Dolichos lablab) at Farmer`s Field Condition: A Survey Finding

    OpenAIRE

    Ahmed, K. U.; M.M.Rahman; Alam, M. Z.; S. U. Ahmed

    2004-01-01

    A survey on farmer`s pest control methods and direct yield loss assessment of country bean (Dolichos lablab) was done during September 2000 to February 2001 in North Edilpur and South Mohadebpur villages of Sitakundu under Chittagong district. Results revealed that farmers used Fanfan, Nogos, Ripcord, Malathion, Roxion and Sumithion as chemical methods and applying ash and handpicking of insect pests as non-chemical method to control insect pests. The frequency of insecticide application duri...

  20. The Use of Qualitative Methods in Large-Scale Evaluation: Improving the Quality of the Evaluation and the Meaningfulness of the Findings

    Science.gov (United States)

    Slayton, Julie; Llosa, Lorena

    2005-01-01

    In light of the current debate over the meaning of "scientifically based research", we argue that qualitative methods should be an essential part of large-scale program evaluations if program effectiveness is to be determined and understood. This article chronicles the challenges involved in incorporating qualitative methods into the large-scale…

  1. A sub-ODE method for finding exact solutions of a generalized KdV-mKdV equation with high-order nonlinear terms

    International Nuclear Information System (INIS)

    The bell type solitary wave solution, the kink type solitary wave solution, the algebraic solitary wave solution and the sinusoidal traveling wave solution of a generalized KdV-mKdV equation (GKdV-mKdV) with high-order nonlinear terms are obtained by a subsidiary ordinary differential equation method (sub-ODE method for short). The key ideas of the sub-ODE method are that the traveling wave solutions of a complicated nonlinear wave equation can be constructed by means of the solutions of some simple and solvable ODEs which are called sub-ODEs

  2. A Fast and Stable Cluster Labeling Method for Support Vector Clustering

    Directory of Open Access Journals (Sweden)

    Huina Li

    2013-12-01

    Full Text Available Even though support vector clustering (SVC is able to handle arbitrary cluster shapes effectively, its popularity is frequently degraded by highly intensive time complexity, poor label performance and even instability for efficiency. To overcome such problems, a fast and stable cluster labeling (FSCL method is proposed. Based on stable equilibrium points, the FSCL first finds an appropriate division of support vectors. With a nonlinear sample sequence strategy presented here, the connected components profiled by support vectors (SVs can be determined in terms of sampling all stable equilibrium point pairs; and the FSCL prefers a density centroid constructed by one subset of SVs, along with a stable equilibrium point, to represent a component while avoiding local optimization. Finally, the remaining data points can be assigned the label of the nearest components with respect to a weighted distance. Time complexity analysis and comparative experiments suggest that the FSCL improves both the efficiency and clustering quality significantly while guaranteeing stability.  

  3. Granulomatous mastitis: radiological findings

    International Nuclear Information System (INIS)

    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

  4. Granulomatous mastitis: radiological findings

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. Causation and methods of skull trepanation in the past from the point of view of the latest findings from the Czech territory.

    Czech Academy of Sciences Publication Activity Database

    Likovský, Jakub; Malyková, Drahomíra; Brzobohatá, Hana; Stránská, Petra

    2010-01-01

    Ro?. 48, ?. 1 (2010), s. 19-32. ISSN 0323-1119 Institutional research plan: CEZ:AV0Z80020508 Keywords : paleopathology * trepanation * trepanation methods * cranial trauma * intracranial hematoma * La Tène period * Middle Ages * Central Europe Subject RIV: AC - Archeology, Anthropology, Ethnology

  6. Methods and demographic findings of the baseline survey of the NEDICES cohort: a door-to-door survey of neurological disorders in three communities from Central Spain

    OpenAIRE

    Morales González, José Manuel; Bermejo Pareja, Félix; Benito-León, Julián; Rivera Navarro, Jesús; Trincado Soriano, Rocío; Gabriel, Rafael; Vega Quiroga, Saturio

    2004-01-01

    To describe the methods and general results of the baseline longitudinal survey in a defined cohort of elderly people from three areas of Central Spain (urban and rural). The survey was designed to study dementia, essential tremor, Parkinson s disease and stroke.

  7. Overtaking method based on sand-sifter mechanism: Why do optimistic value functions find optimal solutions in multi-armed bandit problems?

    Science.gov (United States)

    Ochi, Kento; Kamiura, Moto

    2015-09-01

    A multi-armed bandit problem is a search problem on which a learning agent must select the optimal arm among multiple slot machines generating random rewards. UCB algorithm is one of the most popular methods to solve multi-armed bandit problems. It achieves logarithmic regret performance by coordinating balance between exploration and exploitation. Since UCB algorithms, researchers have empirically known that optimistic value functions exhibit good performance in multi-armed bandit problems. The terms optimistic or optimism might suggest that the value function is sufficiently larger than the sample mean of rewards. The first definition of UCB algorithm is focused on the optimization of regret, and it is not directly based on the optimism of a value function. We need to think the reason why the optimism derives good performance in multi-armed bandit problems. In the present article, we propose a new method, which is called Overtaking method, to solve multi-armed bandit problems. The value function of the proposed method is defined as an upper bound of a confidence interval with respect to an estimator of expected value of reward: the value function asymptotically approaches to the expected value of reward from the upper bound. If the value function is larger than the expected value under the asymptote, then the learning agent is almost sure to be able to obtain the optimal arm. This structure is called sand-sifter mechanism, which has no regrowth of value function of suboptimal arms. It means that the learning agent can play only the current best arm in each time step. Consequently the proposed method achieves high accuracy rate and low regret and some value functions of it can outperform UCB algorithms. This study suggests the advantage of optimism of agents in uncertain environment by one of the simplest frameworks. PMID:26166266

  8. Two methods to estimate the position resolution for straw chambers with strip readout

    International Nuclear Information System (INIS)

    The centroid and charge-ratio methods are presented to estimate the position resolution of the straw chambers with strip readout. For the straw chambers of 10 mm in diameter, the highest position resolution was obtained for a strip pitch of 5 mm. With the centroid method and perpendicular X-ray beam, the position resolution was ?120 ?m, for the signal-to-noise ratio of 60-65. The charge-ratio method has demonstrated ?10% better position resolution at the edges of the strip. 6 refs.; 5 figs

  9. 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

    Scientific Electronic Library Online (English)

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

    Full Text Available [...] Abstract in english 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.

  10. Novel method for combined linkage and genome-wide association analysis finds evidence of distinct genetic architecture for two subtypes of autism.

    OpenAIRE

    Vieland, VJ; Hallmayer, J.; Y. Huang; Pagnamenta, AT; Pinto, D; Khan, H.; Monaco, AP; Paterson, AD; Scherer, SW; Sutcliffe, JS; Szatmari, P

    2011-01-01

    The Autism Genome Project has assembled two large datasets originally designed for linkage analysis and genome-wide association analysis, respectively: 1,069 multiplex families genotyped on the Affymetrix 10 K platform, and 1,129 autism trios genotyped on the Illumina 1 M platform. We set out to exploit this unique pair of resources by analyzing the combined data with a novel statistical method, based on the PPL statistical framework, simultaneously searching for linkage and association to lo...

  11. Feeling blue, going green and finding other attractive alternatives: a case of biphasic anaphylaxis to patent blue and a literature review of alternative sentinel node localisation methods.

    Science.gov (United States)

    Iqbal, Fahad Mujtaba; Basit, Abdul; Salem, Fathi; Vidya, Raghavan

    2015-01-01

    Patent blue dye is used for sentinel lymph node localisation in order to stage the axilla in patients with breast cancer. Patent blue is one of the most common dyes used across the UK, however, the incidence of adverse effects seems to be increasing. This case highlights our experience of a biphasic anaphylactic reaction to patent blue dye, and we conduct a brief literature review of alternative and more novel methods to adequately visualise the lymphatics for sentinel lymph node biopsy. PMID:26670899

  12. Methods of Pest Control and Direct Yield Loss Assessment of Country Bean (Dolichos lablab at Farmer`s Field Condition: A Survey Finding

    Directory of Open Access Journals (Sweden)

    K.U. Ahmed

    2004-01-01

    Full Text Available A survey on farmer`s pest control methods and direct yield loss assessment of country bean (Dolichos lablab was done during September 2000 to February 2001 in North Edilpur and South Mohadebpur villages of Sitakundu under Chittagong district. Results revealed that farmers used Fanfan, Nogos, Ripcord, Malathion, Roxion and Sumithion as chemical methods and applying ash and handpicking of insect pests as non-chemical method to control insect pests. The frequency of insecticide application during flowering stage to harvest was 9 to 15 with waiting period of only 3 to 20 days and 6 to 12 with waiting period of 3 to 25 days in North Edilpur and South Mohadebpur, respectively. The pod infestation by pod borer and aphids varied from 2.29 to 5.12% and from 2.83 to7.16% in North Edilpur and South Mohadebpur, respectively. Insect pests thus caused direct yield loss of 60.38-200.69 kg ha-1 in North Edilpur and 92.63-345.80 kg ha-1 in South Mohadebpur.

  13. Metáforas e Linguística de Corpus: metodologia de análise aplicada a um gênero de negócios Metaphors and Corpus Linguistics: a method for finding metaphors in a business genre

    Directory of Open Access Journals (Sweden)

    Tony Berber Sardinha

    2011-01-01

    Full Text Available O presente trabalho visa a relatar o desenvolvimento de uma metodologia de identificação de metáforas em corpora eletrônicos. Como exemplo, foi tomado o gênero teleconferências de apresentação de resultados financeiros. A metodologia é do tipo "bottom-up" / "corpus-driven" e se baseia na identificação de palavras com frequência marcante (palavras-chave e de seus padrões de co-ocorrência, seguido do cálculo de similaridade semântica entre essas palavras. Com isso, chega-se a um conjunto de palavras que são então interpretadas em seu co-texto, por meio de concordâncias.This paper aims at reporting the development of a method for metaphor identification in computer corpora. The method was tested on a particular corpus, namely of investment conference calls, and comprises procedures that work from the bottom up, and rely on marked frequency, collocation and semantic similarity as signalling devices for metaphor. As such, the method is an example of corpus-driven research into metaphor. The application of these procedures yields a number of metaphor candidates, which are then checked manually through concordances.

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Airborne gamma ray spectrometry - An efficient method for finding and mapping pollution with radioactive elements from uranium extraction and ore mining

    International Nuclear Information System (INIS)

    The concentration of uranium (by radium), thorium and potassium (by the isotope K-40) in the 50 cm surface layer can be defined with relative high precision by the airborne gamma spectrometric surveys. It is well known that certain ore mining and extraction of non-radioactive ores create polluted areas. Pollution can generate from geochemical migration of uranium (radium) and its transport by surface or underground waters. Considerable pollution can be obtained with the so-called ''geochemical barriers'', generated from the change of physical-chemical properties in the surface layer. Accumulations of uranium are formed close to such barriers. There are, of course, other mechanism of radioactive pollution, from mechanical carriage of rock masses, with uranium concentration, to settling of uranium from radioactive waters in the flooded plains. Bulgaria is rich in geological formations of various uranium concentrations, sometimes very high, and we should accept it as variations of the natural radioactive background. This paper explains one of the methods used for eliminating the natural radioactive background when mapping the pollution from the ore mining industry. The example is the Buhovo area and the method described is the airborne gamma ray spectrometry. Information is also provided on the spectrometer KS 16, developed with Bulgarian and Canadian expertise. (author)

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

    Directory of Open Access Journals (Sweden)

    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.

  17. 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

    Science.gov (United States)

    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 tensioning silicone membranes on any given frame geometry. Corona treatment provided a means of increasing adhesion of silicone on carbon fiber through the use of a high-frequency high-voltage air plasma discharge. The silicone membrane is co-cured with carbon fiber under vacuum pressure at an elevated temperature. After cool down, the membrane is tensioned.

  18. A Two-Stage Method for Scientific Papers Analysis

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    DEFF Research Database (Denmark)

    Bundgaard, Eva; Livi, Francesco

    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 of all the polymers corresponding to all combinations of donor and acceptor units is followed by characterization of all the materials with respect to molecular weight, electrochemical energy levels, band gaps, photochemical stability, carrier mobility, and photovoltaic parameters. The photovoltaic evaluation is carried out with specific reference to scalable manufacture, which includes large area (1 cm 2 ), stable inverted device architecture, an indium-tin-oxide-free fully printed flexible front electrode with ZnO/PEDOT:PSS (poly(3,4-ethylenedioxythiophene):polystyrene sulfonate), and a printed 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 included in the merit factor, it is found that 13 out of the 104 synthesized polymers outperformed poly(3-hexylthiophene) under the chosen processing conditions and thus can be suitable for further development.

  1. Finding Cryptography in Object Code

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Find an Endocrinologist

    Science.gov (United States)

    ... Contact a Health Professional What is an Endocrinologist? Endocrinology Find an Endocrinologist Value of an Endocrinologist Learn ... Find an Endocrinologist Share: What is an Endocrinologist? Endocrinology Find an Endocrinologist Value of an Endocrinologist Learn ...

  3. Abdominal aspergillosis: CT findings

    International Nuclear Information System (INIS)

    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.

  4. Abdominal aspergillosis: CT findings

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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

  6. Finding beam focus errors automatically

    International Nuclear Information System (INIS)

    An automated method for finding beam focus errors using an optimization program called COMFORT-PLUS. The steps involved in finding the correction factors using COMFORT-PLUS has been used to find the beam focus errors for two damping rings at the SLAC Linear Collider. The program is to be used as an off-line program to analyze actual measured data for any SLC system. A limitation on the application of this procedure is found to be that it depends on the magnitude of the machine errors. Another is that the program is not totally automated since the user must decide a priori where to look for errors

  7. Modified nonlinearities distribution Homotopy Perturbation method as a tool to find power series solutions to ordinary differential equations / Método modificado de Perturbación Homotópica con distribución de no linealidades como herramienta para encontrar soluciones de ecuaciones diferenciales ordinarias

    Scientific Electronic Library Online (English)

    U., Filobello-Nino; H., Vázquez-Leal; Y., Khan; D., Pereyra-Díaz; A., Pérez-Sesma; A., Díaz-Sánchez; V.M., Jiménez-Fernández; A., Herrera-May; R., López-Martínez; J., Sanchez-Orea.

    Full Text Available En este artículo, el método modificado de perturbación homotópica con distribución de no linealidades (MNDHPM) es utilizado para encontrar soluciones en series de potencias de ecuaciones diferenciales ordinarias, tanto lineales como no lineales. Se verá que el método es particularmente relevante en [...] algunos casos de ecuaciones con coeficientes no polinomiales e inhomogéneas con términos no homogéneos no polinomiales. Abstract in english In this article, modified non-linearities distribution homotopy perturbation method (MNDHPM) is used in order to find power series solutions to ordinary differential equations with initial conditions, both linear and nonlinear. We will see that the method is particularly relevant in some cases of eq [...] uations with non-polynomial coefficients and inhomogeneous non-polynomial terms.

  8. Find a Surgeon

    Science.gov (United States)

    ... to find out more. asc"} Dental Implant Surgery Dental Implant Surgery Dental implant surgery is, of course, surgery, and ... here to find out more. Dental Implant Surgery Dental Implant Surgery Dental implant surgery is, of course, surgery, and ...

  9. Fabrication Aware Form-finding

    DEFF Research Database (Denmark)

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

    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 parts. The first material system employs a novel rotated joint design to allow the structural tuning of quasi-reciprocal timber frame elements fabricated from multi-axis machined plywood sheet stock. T...

  10. Thoracic textilomas: CT findings

    International Nuclear Information System (INIS)

    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)

  11. Thoracic textilomas: CT findings

    Energy Technology Data Exchange (ETDEWEB)

    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)

  12. Dermoscopic findings in cicatricial alopecia

    Directory of Open Access Journals (Sweden)

    Seher Ar?

    2013-12-01

    Full Text Available Background: Dermoscopy is an important tool for the diagnosis of pigmented skin lesions. Newly, this method has also been used in the diagnosis and follow-up hair and scalp disorders. Objective: The objective of this study was to investigate dermoscopic findings in a sample of patients with clinical and histopathological compatible with cicatricial alopecia. Methods: Twenty nine patients with cicatricial alopecia diagnosed by clinical and histological findings were examined by dermoscopy.. Results: Dermoscopic features evaluated included folliculitis decalvans (n=8, pseudopelade of Brocq (n=7, lichen planopilaris (n=6, discoid lupus erythematosus (n=2, dissecting cellulitis (n=1, and secondary cicatricial alopecia (n=5. Visualization of structures previously examined with naked eye were seen in great detail with dermoscopy. The loss of follicular orifices was seen in all patients with cicatricial alopecia. Perifollicular scaling, arborizing red lines, honeycomb pigment pattern, white dots and tufted hairs were the other most obvious findings. Conclusion: Use of dermoscopy in the clinical evaluation of cicatrical alopecia improves diagnostic capability beyond simple clinic inspection, but larger studies correlating dermoscopic findings with histopathology exams are needed to improve understanding of this method.

  13. Finding a Donor

    Science.gov (United States)

    ... MatchView examples Safety of donated marrow or cord blood Contact with your donor FAQs about finding a donor Getting a transplant ... potential matches Safety of donated marrow or cord blood Contact with your donor FAQs about finding a donor If you and ...

  14. Finding Maximal Quasiperiodicities in Strings

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Pedersen, Christian N. S.

    2000-01-01

    Apostolico and Ehrenfeucht defined the notion of a maximal quasiperiodic substring and gave an algorithm that finds all maximal quasiperiodic substrings in a string of length n in time O(n log2 n). In this paper we give an algorithm that finds all maximal quasiperiodic substrings in a string of length n in time O(n log n) and space O(n). Our algorithm uses the suffix tree as the fundamental data structure combined with efficient methods for merging and performing multiple searches in search tree...

  15. CT findings of colonic diverticulitis

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Shigeru; Ohba, Satoru [Nagoya City Univ. (Japan). Medical School; Mizutani, Masaru [and others

    1998-11-01

    Although colonic diverticulitis has no indication for operation, but in some mistaken cases were operated with a diagnosis of acute appendicitis. We evaluated the CT findings of colonic diverticulitis about 19 cases and of asymptomatic colonic diverticula about 15 cases retrospectively. Diagnosis was confirmed of barium enema and operation. CT are complementary methods of examination that can delineated the range of thickening of the colon and the extension of inflammatory changes around the colon. We also believe that CT findings of colonic diverticulitis are useful for differentiating from a diagnosis of appendicitis. (author)

  16. Find a Dentist

    Science.gov (United States)

    ... information you need from the Academy of General Dentistry Monday, October 12, 2015 About | Contact Find an ... more. Disclaimer of Liabilities The Academy of General Dentistry's (AGD) Web site provides a listing of members ...

  17. Find a Urologist

    Science.gov (United States)

    ... Urology Erectile Dysfunction Incontinence Oncology / Cancer Pediatric Urology Renal Transplantation Trauma Submit About Us What We Do Foundation ... Urology Erectile Dysfunction Incontinence Oncology / Cancer Pediatric Urology Renal Transplantation Trauma Submit Start New Search Find a Urologist ...

  18. Hysterosalpingographic findings in infertility

    International Nuclear Information System (INIS)

    Four hundred and fifty four cases of H.S.G. in infertility were analyzed and following brief results were obtained. 1. Most frequent age group was 25-29 year old, and those number of patient were 188 (41.4%). 2. Most frequent abnormal uterine findings was intravasation (113 cases), and malposition (119), irregular margin (104), filling defect (37), and diverticulum (6) in decreasing order. 3. Most frequent abnormal tubal finding was obstruction (199 cases), and hydrosalpinx (99), diverticulosis (22), intravasation (17), peritubal adhesion (13), and beaded tube (10) in decreasing order. 4. Nagative findings was seen in 155 cases (34.1%) of uterus and in 227 cases (50.0%) of fallopian tubes. 5. Nagative findings in both uterus and fallopian tubes was seen only 87 cases (19.2%)

  19. Find a Dermatologist

    Science.gov (United States)

    ... Virgin Islands, U.S. Yemen Zimbabwe Doctor's Last Name: City: State: Choose a State Alabama Alaska Arizona Arkansas ... cancer screening . Use these tips to Be Sun Smart ® . Get the scoop on dermatologists' top tips. Find ...

  20. Finding a PTSD Therapist

    Science.gov (United States)

    ... National Center for PTSD » Public » Finding a Therapist PTSD: National Center for PTSD Menu Menu PTSD PTSD Home For the Public ... Health Connect with us Share this page Search PTSD Site Choose Section Enter Term and Search Advanced ...

  1. O centróide da piscina de água quente do pacífico como um indicador dos fenômenos El Niño e La Niña / The centroid of the pacific warm pool as an index for the El Niño and La Niña phenomena

    Scientific Electronic Library Online (English)

    Fabio Vieira, Machado; Victor de Amorim, d' Ávila.

    2014-09-01

    Full Text Available Os fenômenos oceanográficos El Niño e La Niña foram analisados através do monitoramento da série temporal da componente zonal do centroide da piscina de água quente do Pacífico (PAQ) que descreve movimentos leste-oeste ao longo da faixa intertropical deste oceano. Utilizou-se uma série de dados de t [...] emperatura da superfície do Oceano Pacífico para classificar a PAQ e estimar o seu centroide entre 1981 e 2003. Todos os episódios de El Niño (1982-83; 1986-87; 1990-95; e 1997-98) e La Niña (1984-85; 1988-89; 1998-2000) existentes no período analisado puderam ser observados na série temporal de dados da componente zonal da PAQ (CZPAQ). Os episódios mais intensos de El Niño foram classificados pela ordenação decrescente dos maiores deslocamentos para leste (ranking). A série de dados da CZPAQ se apresentou em fase com o índice de Oscilação Sul e com a anomalia da temperatura superficial do oceano (TSO). As flutuações associadas ao movimento zonal do centroide da PAQ foram observadas no espectro de energia onde ficaram ressaltadas as flutuações interanuais associadas aos fenômenos El Niño e La Niña. Foram observados deslocamentos mais curtos para oeste durante os anos de La Niña, quando comparados aos deslocamentos para leste durante os eventos de El Niño. A migração zonal da PAQ, representada aqui pelo centroide, apresentou-se, portanto, como um indicador dos fenômenos El Niño e La Niña. A principal vantagem dessa técnica é a dependência de um único parâmetro arbitrário, que é o limiar da TSO para delinear a PAQ. Abstract in english The El Niño -La Niña oceanographic phenomena were analized making use of the zonal component of the Pacific warm pool (PAQ) which describes east-west displacements along the intertropical belt of this ocean. We manipulated an ocean surface temperature (TSO) timeseries to classify the PAQ and to esti [...] mate its centroid between 1981 and 2003. All the El Niño (1982-83; 1986-87; 1990-95; e 1997-98) and La Niña (1984-85; 1988-89; 1998-2000) episodes described in the academic literature were eminent in the timeserie of the zonal component of the Pacific warm pool (CZPAQ). The most intense El Niño episodes were ranked according to its furthest eastward displacement. The timeserie of the CZPAQ was in phase with both the TSO anomaly and the Southern Oscillation Index. The fluctuations associated to the CZPAQ were illustraded in the spectrum where interannual oscillations associated to the El Niño -La Niña phenomena were observed. Shorter migrations to the west during the La Niña years were notable in comparison to those eastward moviments during the El Niño events. Therefore, the zonal displacements of the PAQ, represented here by the centroid, were presented as having significant worth to indicate the El Niño and La Niña phenomena. The main advantage of this technique is that it depends on a single arbitrary parameter to represent the PAQ, the threshold of the ocean surface temperature in the Pacific Ocean.

  2. Videonystagmographic Finding in Meniere's Patients

    Directory of Open Access Journals (Sweden)

    Saki Nasser

    2011-07-01

    Full Text Available Back ground and Objective: Vertigo is the most common complaints of patients who refer to physician and menier's disease is one of the most common causes of it. Diagnose of menier's disease depend on clinical finding. Vestibular tests are affect the treatment method and prognosis of disease, to differentiate it from other causes of vertigo as well. In this study we performed evaluation and analysis of videonystagmoghrapy (VNG finding in menier's disease.Subjects and Methods: Total 61 patients with menier’s disease referred to ENT outpatient department of Imam Khomeini and Apadana Hospitals were evaluated with VNG and Sacade, Smooth pursuit, Optokinetic, Positional and caloric tests. SPSS 16 software for data analysis was used.Results: Directional preponderance was found in 11.44%, unilateral weakness in 39.33% and Latency of sacad in 42.6% with abnormal results.Conclusion: There was no significant correlation between severity of vertigo, severity of hearing loss, duration of Disease and videonysta- gmography finding. Unilateral weakness was most important finding in this study. Sci Med J 2011; 10(3:289-293

  3. Ultrasonographic findings of gynecomastia

    Energy Technology Data Exchange (ETDEWEB)

    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

  4. CT findings of ganglioneuroma

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. Infecção pelo Papilomavírus Humano em Adolescentes: Relação com o Método Anticoncepcional, Gravidez, Fumo e Achados Citológicos / Human Papillomavirus Infection in Adolescents: Relation to Contraceptive Method, Pregnancy, Smoking, and Cytologic Findings

    Scientific Electronic Library Online (English)

    Eddie Fernando Candido, Murta; Maria Azniv Hazarabedian de, Souza; Sheila Jorge, Adad; Edward, Araújo Júnior.

    2001-05-01

    Full Text Available Objetivo: avaliar a influência da gravidez, do hábito de fumar, do método anticoncepcional e quais os achados citológicos mais freqüentes em adolescentes com infecção pelo HPV. Métodos: foram analisadas retrospectivamente 54.985 citologias de pacientes atendidas entre julho de 1993 e dezembro de 199 [...] 8. Deste total, 6.498 exames (11,8%) eram de pacientes com idade inferior a 20 anos, sendo que 326 (5,9%) apresentavam sinais citológicos de infecção por HPV, associada ou não a neoplasia intra-epitelial cervical (NIC) grau I. O grupo controle foi composto por 333 pacientes na mesma faixa etária, sem sinais citológicos de infecção por HPV. Resultados: a infecção pelo HPV foi mais freqüente nas adolescentes que fazem uso de anticoncepcionais orais (16,9% versus 13,8%, p Abstract in english Purpose: to evaluate the influence of pregnancy, habit of smoking, and the contraceptive method in HPV infection and the frequency of cytologic findings in adolescent women with HPV infection. Methods: a total of 54,985 cytologic examinations of patients seen between July, 1993 and December, 1998 we [...] re retrospectively analyzed. Of this total, 6,498 (11.8%) examinations were from patients under 20 years old. Of the total of 6,498 cytologic examinations, 326 (5.9%) presented signs of HPV infection, with or without grade I cervical intraepithelial neoplasia (CIN). Patients with diagnosis of grade II and III CIN were excluded. The control group consisted of 333 patients paired by age, without cytological signs of HPV infection. Results: in adolescents, HPV infection was more frequent in oral contraceptive users (16.9% versus 13.8%, p

  6. Finding optimal exact reducts

    KAUST Repository

    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. Novel method of detecting movement of the interference fringes using one-dimensional PSD.

    Science.gov (United States)

    Wang, Qi; Xia, Ji; Liu, Xu; Zhao, Yong

    2015-01-01

    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 ?m. 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. PMID:26043175

  8. Novel Method of Detecting Movement of the Interference Fringes Using One-Dimensional PSD

    Directory of Open Access Journals (Sweden)

    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 ?m. 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.

  9. 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 ?9-tetrahydrocannabinolic acid A concentrations.

    Science.gov (United States)

    Moosmann, Bjoern; Roth, Nadine; Hastedt, Martin; Jacobsen-Bauer, Andrea; Pragst, Fritz; Auwärter, Volker

    2015-05-01

    Hair analysis for drugs and drugs of abuse is increasingly applied in child protection cases. To determine the potential risk to a child living in a household where drugs are consumed, not only can the hair of the parents be analyzed but also the hair of the child. In the case of hair analysis for cannabinoids, the differentiation between external contamination and systemic uptake is particularly difficult, since the drug is quite often handled extensively prior to consumption (e.g. when preparing a joint) and smoke causes a further risk for an external contamination. ?9-tetrahydrocannabinolic acid A (THCA-A), the non-psychoactive biogenetic precursor of ?9-tetrahydrocannabinol (THC), is a suitable marker for external contamination since it is not incorporated into the hair matrix through the bloodstream in relevant amounts. In the presented study, hair samples from 41 children, 4 teenagers, and 34 drug-consuming parents were analyzed for THCA-A, THC and cannabinol (CBN) applying methanolic extraction and a fully validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method (Method 1). For comparison, a part of the samples was also analyzed applying alkaline hydrolysis followed by liquid/liquid extraction and gas chromatography-mass spectrometry (GC-M)S (Method 2), or by headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) (Method 3). Furthermore, 458 seized marihuana samples and 180 seized hashish samples were analyzed for the same cannabinoids by gas-chromatography-flame ionization detector (GC-FID). In all but one of the hair samples, the concentration of THCA-A was higher than the concentration of THC and in 14 cases no THC could be detected despite the presence of THCA-A, suggesting that in almost all cases a significant external contamination had occurred. Within-family comparison showed a higher THCA-A/THC ratio in hair of children than of their consuming caregivers. Mean and median of this ratio of all 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

  10. FindZebra

    DEFF Research Database (Denmark)

    Dragusin, Radu; Petcu, Paula; Lioma, Christina; Larsen, Birger; Jørgensen, Henrik L; Cox, Ingemar Johansson; Hansen, Lars Kai; Ingwersen, Peter; Winther, Ole

    2013-01-01

    Background: The web has become a primary information resource about illnesses and treatments for both medical and non-medical users. Standard web search is by far the most common interface to this information. It is therefore of interest to find out how well web search engines work for diagnostic queries and what factors contribute to successes and failures. Among diseases, rare (or orphan) diseases represent an especially challenging and thus interesting class to diagnose as each is rare, diver...

  11. Heterotopic pregnancy: Sonographic findings

    International Nuclear Information System (INIS)

    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.

  12. BIOMOD - preliminary findings

    International Nuclear Information System (INIS)

    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)

  13. Heterotopic pregnancy: Sonographic findings

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. Brain venous pathologies: MRI findings

    International Nuclear Information System (INIS)

    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)

  15. Imaging Findings of Gastric Diverticula

    OpenAIRE

    Dominik Schramm; Andreas Gunter Bach; Alexander Zipprich; Alexey Surov

    2014-01-01

    Introduction. Gastric diverticula (GD) are very rare. Computer tomographic findings in GD have been reported only as case reports previously. The aim of this study was to estimate the prevalence of GD on computed tomography (CT) and to analyze their radiological appearances. Materials and Methods. From 2006 to 2013, a total of 14,428 patients were examined by abdominal/thoracic CT at our institution. GD were diagnosed in 18 (0.12%) patients (13 women and 5 men, median age, 64 years). In 9 pat...

  16. Finding things out

    CERN Document Server

    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

  17. Normal radiological findings

    International Nuclear Information System (INIS)

    This book is intended for learners in radiology, presenting a wealth of normal radiological findings together with a systematic guide for appraisal and interpretation, and for formulation of reports. The text examples and criteria given will help beginners in learning to 'read' a radiograph, and to verify their conclusions by means of checklists and standard reports. The case material covers numerous illustrations from the following sectors: Skeletal radiography, mammography, tomography, contrast radiography, organ examination by intravenous techniques, arthrography and angiography, and specialized radiography, (ECB) With 184 figs

  18. Application of multiattribute decision-making methods for the determination of relative significance factor of impact categories.

    Science.gov (United States)

    Noh, Jaesung; Lee, Kun Mo

    2003-05-01

    A relative significance factor (f(i)) of an impact category is the external weight of the impact category. The objective of this study is to propose a systematic and easy-to-use method for the determination of f(i). Multiattribute decision-making (MADM) methods including the analytical hierarchy process (AHP), the rank-order centroid method, and the fuzzy method were evaluated for this purpose. The results and practical aspects of using the three methods are compared. Each method shows the same trend, with minor differences in the value of f(i). Thus, all three methods can be applied to the determination of f(i). The rank order centroid method reduces the number of pairwise comparisons by placing the alternatives in order, although it has inherent weakness over the fuzzy method in expressing the degree of vagueness associated with assigning weights to criteria and alternatives. The rank order centroid method is considered a practical method for the determination of f(i) because it is easier and simpler to use compared to the AHP and the fuzzy method. PMID:12719893

  19. Tomographic and pathological findings in pulmonary sarcoidosis

    Energy Technology Data Exchange (ETDEWEB)

    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)

  20. Finding Communities of Related Genes

    CERN Document Server

    Wilkinson, D; Wilkinson, Dennis; Huberman, Bernardo A.

    2002-01-01

    We present an automated method of identifying communities of functionally related genes from the biomedical literature. These communities encapsulate human gene and protein interactions and identify groups of genes that are complementary in their function. We use graphs to represent the network of gene cooccurrences in articles mentioning particular keywords, and find that these graphs consist of one giant connected component and many small ones. In addition, the vertex degree distribution of the graphs follows a power law, whose exponent we determine. We then use an algorithm based on betweenness centrality to identify community structures within the giant component. The different structures are then aggregated into a final list of communities, whose members are weighted according to how strongly they belong to them. Our method is efficient enough to be applicable to the entire Medline database, and yet the information it extracts is significantly detailed, applicable to a particular problem, and interesting...

  1. Ultrasonographic findings of Epicondylitis

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Climate change: Recent findings

    International Nuclear Information System (INIS)

    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

  3. MR findings in mannosidosis

    International Nuclear Information System (INIS)

    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.)

  4. Ultrasonic range finding

    International Nuclear Information System (INIS)

    The patent concerns ultrasonic range finding equipment which can be employed in a nuclear reactor to monitor the spacing between structural components which are under stress. The invention is described with reference to the general layout of a pool-type liquid metal cooled fast breeder reactor. The equipment includes a generated reference signal, a portion of which is used to produce an ultrasonic beam which is directed towards a target. The ultrasonic beam is then reflected as an echo and received by a transducer. The pulse echo transit time and the phase displacement of the echo signal with respect to the reference signal, gives a measure of the range of the target with a high degree of precision. (U.K.)

  5. Radiologic findings of dwarfism

    International Nuclear Information System (INIS)

    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

  6. Ultrasonographic findings of retinoblastoma

    International Nuclear Information System (INIS)

    Retinoblastoma is the most common intraocular tumor in infants and young children which has relatively favorable prognosis with early diagnosis and adequate treatment, however, it can be lethal if the treatment is delayed or inadequate. Clinically, early diagnosis is often difficult because of minimal subjective and objective signs and symptoms, and the patients are usually too young to complain visual disturbance. When ophthalmoscopicexamination is impossible due to presence of opaue media in front of tumor mass as associated inflammatory reaction, hemorrhage, corneal opacity, retinal detachment, etc, ultrasonography is necessary for diagnosis of retinoblastoma. Authors analyzed ultrasonographic al findings with pathological correlation on 10 cases of confirmed retinoblastoma during the period of March 1981 to September1982 at the Seoul National University Hospital. In all cases, ultrasonography demonstrates intraocular masses and all of which are cystic type.Reflectivity of masses are higher than retroorbital fat tissue in 8 cases, and 7 cases show irregular internal echogenic texture. There is no correlation between reflexivity and internal echogenic texture with microscopic findings as rosette, pseudo rosette and micro cysts. Calcifications are demonstrated by ultrasonography as strong reflectiveness with posterior sonic shadowing in 9 cases and 9 of 10 cases are well correlated with calcifications in pathologic specimens. Anechoic cystic areas are shown in 9 cases, and 6 of 10 cases are well correlated with necrosis in pathologic specimen. In all cases, there is no attenuation of sound within tumor masses, and no demonstrable choroidal excavation. Associated retinal detachment is hardly identifiable in irregular contour and internal texture of cystic tumor masses

  7. The Brain and Spinal Injury Center score: a novel, simple, and reproducible method for assessing the severity of acute cervical spinal cord injury with axial T2-weighted MRI findings.

    Science.gov (United States)

    Talbott, Jason F; Whetstone, William D; Readdy, William J; Ferguson, Adam R; Bresnahan, Jacqueline C; Saigal, Rajiv; Hawryluk, Gregory W J; Beattie, Michael S; Mabray, Marc C; Pan, Jonathan Z; Manley, Geoffrey T; Dhall, Sanjay S

    2015-10-01

    OBJECT Previous studies that have evaluated the prognostic value of abnormal changes in signals on T2-weighted MRI scans of an injured spinal cord have focused on the longitudinal extent of this signal abnormality in the sagittal plane. Although the transverse extent of injury and the degree of spared spinal cord white matter have been shown to be important for predicting outcomes in preclinical animal models of spinal cord injury (SCI), surprisingly little is known about the prognostic value of altered T2 relaxivity in humans in the axial plane. METHODS The authors undertook a retrospective chart review of 60 patients who met the inclusion criteria of this study and presented to the authors' Level I trauma center with an acute blunt traumatic cervical SCI. Within 48 hours of admission, all patients underwent MRI examination, which included axial and sagittal T2 images. Neurological symptoms, evaluated with the grades according to the American Spinal Injury Association (ASIA) Impairment Scale (AIS), at the time of admission and at hospital discharge were correlated with MRI findings. Five distinct patterns of intramedullary spinal cord T2 signal abnormality were defined in the axial plane at the injury epicenter. These patterns were assigned ordinal values ranging from 0 to 4, referred to as the Brain and Spinal Injury Center (BASIC) scores, which encompassed the spectrum of SCI severity. RESULTS The BASIC score strongly correlated with neurological symptoms at the time of both hospital admission and discharge. It also distinguished patients initially presenting with complete injury who improved by at least one AIS grade by the time of discharge from those whose injury did not improve. The authors' proposed score was rapid to apply and showed excellent interrater reliability. CONCLUSIONS The authors describe a novel 5-point ordinal MRI score for classifying acute SCIs on the basis of axial T2-weighted imaging. The proposed BASIC score stratifies the SCIs according to the extent of transverse T2 signal abnormality during the acute phase of the injury. The new score improves on current MRI-based prognostic descriptions for SCI by reflecting functionally and anatomically significant patterns of intramedullary T2 signal abnormality in the axial plane. PMID:26161519

  8. The color doppler ultrasonography findings of leptospirosis

    International Nuclear Information System (INIS)

    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)

  9. Pupillographic findings in neglect

    OpenAIRE

    Kim, M; Schwartz, R.; Heilman, K

    1999-01-01

    OBJECTIVES—Unilateral sensory neglect has been attributed to various defects, including a hemispatial attention-arousal deficit. However, support for this hypothesis has only been indirect. Therefore, the purpose of this study was to further test the hemispatial attentional-arousal hypothesis by measuring pupillary response as an index of arousal.?METHODS—There were two experimental subjects with neglect and six matched controls. Stimuli (Arabic numbers) were presented on...

  10. Radiographic findings in immunodeficiency

    International Nuclear Information System (INIS)

    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

  11. Pulmonary sarcoidosis: CT findings

    International Nuclear Information System (INIS)

    Pulmonary sarcoidosis is a systemic disease of unknown cause characterized by the presence of noncaseating granulomas: the associated morbidity and mortality is usually due to pulmonary involvement. To determine the radiological signs of pulmonary sarcoidosis according to high-resolution computed tomography (HRCT) and compare our results with those reported elsewhere. We have made no attempt to establish a correlation between the plain radiographic image and that resulting from HRCT or between the radiologic image and the results of the pathologic study. We employed HRCT to study a series of 21 patients (15 women and 6 men) confirmed by biopsy as having sarcoidosis. The signs assessed include: nodules, ground glass, septal lines, non septal lines, honey combing, architectural changes, traction bronchiectasis and lymphadenopathy. The most common finding, observed in 20 of the 21 cases (95%), were nodules. Their distribution was mainly peribronchovascular or peripherally centrilobular and subpleural. The remaining signs were much more inconsistent and were associated with maximal nodular involvement. The presence of nodular images arranged as described above is typical of sarcoidosis and when observed in the proper clinical context is practically diagnostic of this lesion. (Author) 10 refs

  12. Findings of autopsy imaging

    International Nuclear Information System (INIS)

    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.)

  13. Verified scientific findings

    International Nuclear Information System (INIS)

    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.)

  14. Sonographic Findings of Human Fascioliasis

    Directory of Open Access Journals (Sweden)

    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.

  15. Pathological findings in SIDS.

    Science.gov (United States)

    Berry, P J

    1992-11-01

    The original 1969 definition of SIDS as "unexpected by history" and "unexplained after thorough postmortem examination" is under review in the light of two decades of experience. Suggested modifications include restricting the age to less than 1 year, stipulating that the necropsy includes appropriate histology and laboratory tests, and requiring a review of the clinical history and examination of the death scene. The use of a protocol is recommended both by professional and parent groups. Although the diagnosis of SIDS is to some extent one of exclusion, there are several typical findings which are of value in diagnosis and suggest new avenues for research. External examination is important to exclude trauma and signs of suffocation. A recent study has confirmed that petechiae on the face are rare in SIDS and if found raise the question of deliberate or accidental suffocation. Frothy fluid escaping from the nose and mouth is seen in about half of infants who die from SIDS. Postmortem hypostatic staining as an indicator of position has assumed increased importance since prone sleeping has been shown to be a major risk factor for SIDS. Evidence of sweat in clothing suggests overwrapping. Internal examination shows subserosal petechial haemorrhages in the thymus in most cases. These may be related to age and are commoner in babies dying of SIDS than in controls. Relative sparing of the cervical extension of the thymus is strong evidence for negative intrathoracic pressure, perhaps due to upper or lower airway obstruction. Other typical findings are liquid heart blood, prominent lymph nodes, and an empty bladder (which frustrates some biochemical tests in about half of cases). The lungs are usually well inflated, arguing against surfactant deficiency as a significant cause of SIDS. Microscopic evidence of pulmonary oedema and congestion is found in infant deaths for many reasons and is not discriminatory for SIDS. Minor inflammation and infection of the respiratory tract is common in SIDS and may be important by contributing to overheating, apnoea, or sensitisation to bacterial toxins. Mild fatty change in the liver is very common in infant deaths. Panlobular microvesicular fatty change is rare and may require special stains for its recognition. It indicates the necessity of searching for inherited biochemical disorders. Although these are rare in true SIDS, they are an important cause of unexpected death in infancy. Of Naeye's "tissue markers of hypoxia'', extramedullary haemopoiesis in the liver and brainstem gliosis have been confirmed. Persistence of fetal haemoglobin and raised hypoxanthine values in vitreous humour are further pointers to periods of premortem hypoxia. Painstaking neuropathology has shown delayed myelination and maturation of dendritic spines. Changes in the brain may explain the link between antenatal factors such as smoking and SIDS. A second cot death in a family requires expert examination. Minor injuries or unexplained apnoeic spells may be important retrospective clues to non-accidental injury. Investigations mus exclude inherited disorders before the death is ascribed to SIDS. Parents demand that the pathologist takes care of their baby before, during, and after the necropsy, carries out the procedure to a high standard, checks reconstruction of the body, facilitates access, and is responsible for communicating the results of the examination. The "SIDS postmortem" presents both a practical and an intellectual challenge. PMID:1474151

  16. Pulmonary talcosis: imaging findings.

    Science.gov (United States)

    Marchiori, Edson; Lourenço, Sílvia; Gasparetto, Taisa Davaus; Zanetti, Gláucia; Mano, Cláudia Mauro; Nobre, Luiz Felipe

    2010-04-01

    Talc is a mineral widely used in the ceramic, paper, plastics, rubber, paint, and cosmetic industries. Four distinct forms of pulmonary disease caused by talc have been defined. Three of them (talcosilicosis, talcoasbestosis, and pure talcosis) are associated with aspiration and differ in the composition of the inhaled substance. The fourth form, a result of intravenous administration of talc, is seen in drug users who inject medications intended for oral use. The disease most commonly affects men, with a mean age in the fourth decade of life. Presentation of patients with talc granulomatosis can range from asymptomatic to fulminant disease. Symptomatic patients typically present with nonspecific complaints, including progressive exertional dyspnea, and cough. Late complications include chronic respiratory failure, emphysema, pulmonary arterial hypertension, and cor pulmonale. History of occupational exposure or of drug addiction is the major clue to the diagnosis. The high-resolution computed tomography (HRCT) finding of small centrilobular nodules associated with heterogeneous conglomerate masses containing high-density amorphous areas, with or without panlobular emphysema in the lower lobes, is highly suggestive of pulmonary talcosis. The characteristic histopathologic feature in talc pneumoconiosis is the striking appearance of birefringent, needle-shaped particles of talc seen within the giant cells and in the areas of pulmonary fibrosis with the use of polarized light. In conclusion, computed tomography can play an important role in the diagnosis of pulmonary talcosis, since suggestive patterns may be observed. The presence of these patterns in drug abusers or in patients with an occupational history of exposure to talc is highly suggestive of pulmonary talcosis. PMID:20155272

  17. A new method for designing floor slabs on grade due to the difficulty of applying simplified design methods, amongst them being the Portland Cement Association (PCA) and Wire Reinforcement Institute (WRI) methods

    OpenAIRE

    Hugo Ernesto Camero Sanabrial

    2010-01-01

    This article presents a methodology for designing slabs on grade for industrial floors where there is an eccentricity between the slab centroid and the gravity centre loads of the loaded axle of forklift trucks travelling over the floor. An example was used for analysing how Portland Cement Association (PCA) and the Wire Reinforcement Institute (WRI) methods are inadequate for designing floors sublected to this condition. The new proposal for designing slabs on grade for industrial floors h...

  18. Neutropenic enterocolitis: CT findings

    International Nuclear Information System (INIS)

    Purpose: to evaluate the role of computed tomography (CT) in the diagnosis of neutropenic enterocolitis (NEC). Material and Methods: we studied 7 immunocompromised patients (6 male, 1 female, age range: 30-75 years, mean: 57.7 years), due to treatment of malignant tumors. All these had clinical symptoms and signs consistent with neutropenic enterocolitis. Results: CT showed thickening of the bowel wall (n=7), changes in fat density (n=5) and free fluid in abdominal cavity (n=3). One patient received surgical treatment due to a toxic megacolon. Four patients died due to multi organic failure. Three patients showed a favorable clinical evolution. Conclusions: CT contributes significantly to the diagnosis of NEC in immunocompromised patients with clinical suspicion of this pathology. (author)

  19. Ultrasonographic findings of ovarian tumors

    International Nuclear Information System (INIS)

    The ultrasound is easily available and noninvasive diagnostic method without radiation hazard. We can approach to differential diagnosis of ovarian tumors by gray scale ultrasound which can display the detailed structure of soft tissue. In department of radiology, Korea Veterans Hospital, 27 cases of histologically confirmed ovarian tumors collected from March 1984 to February 1986 were analyzed. The results were as follows: 1. The age distribution was from 13 to 72 years. 2. The histologic diagnosis of ovarian tumors (27 cases) are as follows; teratoma (14), mucinous cystadenoma (8), mucinous cystadenocarcinoma (1), serous cystadenoma (2), Krukenburg tumor (1) and malignant thecoma (1). 3. The long diameter of ovarian tumors ranges from 4 cm to 28 cm. In these, mucinous cystadenoma is the largest and their size are as follows; less than 10 cm; 25%, 11-15 cm; 12%, 16-20 cm; 25% and more than 20 cm; 38%. 4. The ultrasonographic findings of teratoma (14) were mainly cystic (8) or echogenic (6). There were echogenic solid components showing distal acoustic shadowing or fat-fluid level within cystic masses. Echogenecity of solid masses was heterogenous. 5. The ultrasonographic findings of mucinous cystadenoma and cystadenocarcinoma (9) were unilocular cystic (3) or multilocular cystic (6). There were variable amount of echogenic component within cystic masses. 6. Those of serous cystadenoma (2) were unilocular cystic (1) or multilocular cystic (1). 7. Krukenburg tumor (1) and Malignant thecoma (1) were heterogenously echogenic.

  20. A method to search for bulk motions in the ICM with {\\sl Chandra} CCD spectra: application to the Bullet cluster

    CERN Document Server

    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 $(46\\pm 13)$ ...

  1. Hippocampal malrotation: MRI findings

    International Nuclear Information System (INIS)

    Purpose: To demonstrate the common features of hippocampus malrotation in patients with epilepsy by volumetric and high-resolution MRI. Material and methods: MRI study was performed in 5 patients (2 females and 3 males) ages ranged between 6-41 years (average: 25 years), all of them with epilepsy diagnosis. MRI was performed with a 1.5 T (GE Signa). The epilepsy protocol include sagittal T1, axial T1 and T2, coronal FLAIR, coronal T2 (high-resolution) and volumetric 3D SPGR IR 1.5 mm thick sequences. Results: The common features found in all patients were: a) Incomplete inversion and round configuration of the hippocampus; b) Unilateral affectation; c) Variable affectation of the hippocampus; d) Normal signal intensity; e) Modification of the inner structure of the hippocampus; f) Abnormal angularity of the collateral sulcus; g) Abnormal position and size of the fornix; h) Normal size of the temporal lobe; and i) Enlargement of the temporal horn with particular configuration. Conclusion: Hippocampus malrotation is a malformation that should be included in the differential diagnosis of the epilepsy patients. MRI provides accurate information for the diagnosis. (author)

  2. Presentation of findings

    International Nuclear Information System (INIS)

    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 the Safety of Radioactive Waste Management. The overall decommissioning strategy to be adopted should be identified as early as possible in the planning process. The presentations and discussions at this conference indicated a distinct shift towards immediate dismantling as a preferred strategy. Turning to social issues, the participation of the public, including community leaders, work forces and interest groups, in the decision making processes should be initiated as early as possible and should continue throughout the process. The aim is to minimize the negative social and economic effects of decommissioning. In the discussion on waste management issues, it was noted that there was progress on the provision of national repositories for radioactive waste would be of great benefit to decommissioning. The long term retention of knowledge is of great importance in two respects: people and records. Funding is clearly vital to decommissioning. Provision needs to be made to ensure that sufficient funds will be available, with a high degree of confidence, when they are needed. An appropriate mechanism should be in place before a new facility is licensed to operate. With regard to the removal of regulatory controls, it was noted that the recycling or reuse of materials from decommissioning can greatly reduce the amount of waste that needs to be disposed of in a repository.This can preserve resources and repository capacity. Criteria for the international trade in such materials are needed, and therefore should be internationally agreed. A great deal of work has been done aimed at establishing criteria for the removal of materials from regulatory control.Work aimed at reaching international consensus on an acceptable methodology, including codes and scenarios, for establishing clearance levels should continue. Questions remain as to whether the criteria for the release of sites should be the same as those for materials, whether natural and artificial radionuclides can be subject to the same criteria, and whether there is a market for materials released from a nuclear fa

  3. Method for finding firing sequences for the reachability problem of Petri nets with mathematical programming technique; Suri keikakuho ni yoru petri net no katatsu mondai ni okeru hakka keiretsu no sosaku shuho

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Y.; Sekiguchi, Y. [Yokohama National University, Yokohama (Japan)

    1996-01-20

    This paper describes a method to expand a matrix equation so that a firing condition in transition can be considered and search the firing sequences in the reachability problem of Petri nets. An attempt has been made to formulate a firing sequence searching problem as a complete integer solution planning problem, and contract it by using a kind of negative-state enumeration method. Effectiveness of this method was discussed through simple numerical examples. This method would allow efficient search of a systematized firing sequence, using partial assembly of reachable markings as the object. The proposed method of contracting the firing sequence searching problem is based on a linearity planning method that can solve a problem with an amount of calculation in the order of multiple term formula for the size of the problem. However, if the size of the subject Petri net grows larger to a certain extent, it is not possible to avoid remarkable increase in the required calculation time and memory capacity. It is intended to discuss, while considering these points, further improvement in the efficiency of this method, such as introduction of an analysis method of the large-size linearity planning problem. 9 refs., 1 fig., 1 tab.

  4. MR findings of polymyositis / dermatomyositis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hak Soo; Joo, Kyung Bin; Moon, Won Jin; Lee, Tae Hee; Park, Ki Ho; Park, Dong Woo; Hahm, Chang Kok [Hanyang Univ. College of Medicine, Seoul (Korea, Republic of)

    1998-07-01

    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 useful for the evaluation of muscle involvement and correlated closely with disease activity; signal intensity ratio could not be substituted for the serum level of muscle enzymes. The group of thigh muscles most affected was the vastus muscles, while the hamstring muscles were least affected. The chemical-shift artifact corresponded mainly to perimuscular edema and did not correlate with disease activity.

  5. MR findings of polymyositis / dermatomyositis

    International Nuclear Information System (INIS)

    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 useful for the evaluation of muscle involvement and correlated closely with disease activity; signal intensity ratio could not be substituted for the serum level of muscle enzymes. The group of thigh muscles most affected was the vastus muscles, while the hamstring muscles were least affected. The chemical-shift artifact corresponded mainly to perimuscular edema and did not correlate with disease activity

  6. Improve the Robustness of Range-Free Localization Methods on Wireless Sensor Networks using Recursive Position Estimation Algorithms

    OpenAIRE

    Gamantyo Hendrantoro; Wirawan; Kristalina Prima

    2011-01-01

    The position of a sensor node at wireless sensor networks determines the received data sensing accuracy. By the knowledge of sensor positioning, the location of target sensed can be estimated. Localization techniques used to find out the position of sensor node by considering the distance of this sensor from the vicinity reference nodes. Centroid Algorithm is a robust, simple and low cost localization technique without dependence on hardware requirement. We propose Recursive Position Estimat...

  7. Learning as way-finding

    DEFF Research Database (Denmark)

    Dau, Susanne

    This paper is based on case study findings from studying undergraduate students’ perceptions of their navigation in a blended learning environment where different learning spaces are offered. In this paper learning is regarded as a multi-level and multi complex concept. In this regard the concept of learning used in this paper is inspired by the latest work of the Danish professor Illeris and the interwoven concept of knowledge development as revealed in the SECI-model generated by the Japanese professors Nonaka and Takeuchi. The empirical investigation, which is the basis of the presented assumptions, is based on the findings from research of the implementation of blended learning in two undergraduate programmes at University College North in Denmark. The data collection methods is based on eighteen focus-group interview collected in a period of the first two years of students enrolment in radiography and teachers education. Furthermore, a survey was conducted after three month of students’ enrolment and some few observations-studies in teachers’ education. The empirical data are interpreted in a narrative form through the use of prefiguration, configuration and refiguration and presented as themes around plots in a narrative form. The findings reveal that students’ use of different learning spaces are challenged by inhabited and embodied practices as well as disruptions. It is argued that learning must be viewed in the light of the new technological possibilities and challenges in spaces. There seem to be “blurred ecotones” between studying, leisure, sociality, identity-seeking and daily life which demands for an extension of the concept of learning. It is stressed that learning are conditioned by contextual orientations-processes in peripersonal spaces. Spaces of learning seem to guide how learning can be afforded and which kinds of learning. It is revealed that learning can be both constructed socially and individually but is constituted by the contextual orientation of the learner/s. Based on these findings it is suggested that learning (both formal and informal) can be conceptualized as way-finding both embodied, emotionally and/or cognitive. Way-finding, is argued, to be a concept for learning processes, knowledge development and identity-shaping where humans learn through motions, feeling and thinking in a world in motion and through combined actions of human and non-human agencies. Furthermore it is argued that cognitive learning-processes are intertwined with embodied learning, and that there are different levels of reflection, cognition and learning driven by outer and inner motifs, meaning, experiences, habits and outer conditions. In the discussion I suggest that learning in this century must take conditions of attention overload into account as an everyday condition which is more than ever actualized by the extended disruptions both by the information technology and other spaces. Based on the discussion areas for future research are suggested.

  8. Finding Flow Experience in Music Activity

    Directory of Open Access Journals (Sweden)

    Dewi Sartika

    2014-03-01

    Full Text Available This research is aim to describe how one finding flow experience in his music activity, experiencing flow and feeling the impact of flow experience to his music career and life. The research method used is qualitative, intrinsic study case. The participants are two famous jazz musicians in Bandung, West Java, Indonesia. Data collecting used are in-depth interview, participant observation and document. The result shows that participant who has environment support especially from his music teacher is not only easier to find and experience flow, but also find happiness as impact of his flow experience. On the other hand, another participant who doesn’t have environment support especially from his family and have personality disposition to use his cognition, is struggling to find his flow experience in playing music, but then he finally find it when composing music.

  9. The multidimensional evaluation and treatment of anxiety in children and adolescents: rationale, design, methods and preliminary findings Avaliação multidimensional e tratamento da ansiedade em crianças e adolescentes: marco teórico, desenho, métodos e resultados preliminares

    OpenAIRE

    Giovanni Abrahão Salum; Luciano Rassier Isolan; Vera Lúcia Bosa; Andrea Goya Tocchetto; Stefania Pigatto Teche; Ilaine Schuch; Jandira Rahmeier Costa; Marianna de Abreu Costa; Rafaela Behs Jarros; Maria Augusta Mansur; Daniela Knijnik; Estácio Amaro Silva; Christian Kieling; Maria Helena Oliveira; Elza Medeiros

    2011-01-01

    OBJECTIVE: This study aims to describe the design, methods and sample characteristics of the Multidimensional Evaluation and Treatment of Anxiety in Children and Adolescents - the PROTAIA Project. METHOD: Students between 10 and 17 years old from all six schools belonging to the catchment area of the Primary Care Unit of Hospital de Clínicas de Porto Alegre were included in the project. It comprises five phases: (1) a community screening phase; (2) a psychiatric diagnostic phase; (3) a multid...

  10. A Blind Method to Detrend Instrumental Systematics in Exoplanetary Light Curves

    Science.gov (United States)

    Morello, G.

    2015-07-01

    The study of the atmospheres of transiting exoplanets requires a photometric precision, and repeatability, of one part in ?104. This is beyond the original calibration plans of current observatories, hence the necessity to disentangle the instrumental systematics from the astrophysical signals in raw data sets. Most methods used in the literature are based on an approximate instrument model. The choice of parameters of the model and their functional forms can sometimes be subjective, causing controversies in the literature. Recently, Morello et al. (2014, 2015) have developed a non-parametric detrending method that gave coherent and repeatable results when applied to Spitzer/IRAC data sets that were debated in the literature. Said method is based on independent component analysis (ICA) of individual pixel time-series, hereafter “pixel-ICA”. The main purpose of this paper is to investigate the limits and advantages of pixel-ICA on a series of simulated data sets with different instrument properties, and a range of jitter timescales and shapes, non-stationarity, sudden change points, etc. The performances of pixel-ICA are compared against the ones of other methods, in particular polynomial centroid division, and pixel-level decorrelation method. We find that in simulated cases pixel-ICA performs as well or better than other methods, and it also guarantees a higher degree of objectivity, because of its purely statistical foundation with no prior information on the instrument systematics. The results of this paper, together with previous analyses of Spitzer/IRAC data sets, suggest that photometric precision and repeatability of one part in 104 can be achieved with current infrared space instruments.

  11. A Medoid-based Method for Clustering Categorical Data

    Directory of Open Access Journals (Sweden)

    Ali Seman

    2013-01-01

    Full Text Available Medoid-based method is an alternative technique to centroid-based method for partitional clustering algorithms. This method has been incorporated in a recently introduced clustering algorithm for categorical data, called k-Approximate Modal Haplotype (k-AMH algorithm. This study reports the performance evaluation between the medoid-based method represented by the k-AMH algorithm and the centroid-based method represented by the extended k-Mode algorithm, the k-Population algorithm and the new Fuzzy k-Mode algorithm in clustering common categorical data. Nine common categorical data sets were used in the experiments to compare the performance of both methods using clustering accuracy scores. In overall results, the medoid-based method of k-AMH algorithm produced significant results for all data sets. The method showed its advantage of obtaining the highest clustering accuracy of 0.94 when clustering large number of clusters. This result indicated that the medoid-based method has a significant contribution for clustering categorical data, particularly for clustering large number of clusters.

  12. An Investigation of the Academic Information Finding and Re-finding Behavior on the Web

    Directory of Open Access Journals (Sweden)

    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

  13. Radiographic findings of Proteus Syndrome

    Directory of Open Access Journals (Sweden)

    Nishant Mukesh Gandhi, MD

    2014-01-01

    Full Text Available The extremely rare Proteus Syndrome is a hamartomatous congenital syndrome with substantial variability between clinical patient presentations. The diagnostic criteria consist of a multitude of clinical findings including hemihypertrophy, macrodactyly, epidermal nevi, subcutaneous hamartomatous tumors, and bony abnormalities. These clinical findings correlate with striking radiographic findings.

  14. Findings

    Science.gov (United States)

    ... Drugs in the Body, Pharmacogenomics, Drug Design, Anesthesiology, Toxicology Physical Trauma and Sepsis Traumatic Injury, Burns, Inflammation, Sepsis, Wound Healing, Immunology Structural Biology Molecular Structure and Function, Protein Folding, Research Tools and ...

  15. MR findings in intralabyrinthine schwannomas

    Energy Technology Data Exchange (ETDEWEB)

    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)

  16. MR findings in intralabyrinthine schwannomas

    International Nuclear Information System (INIS)

    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)

  17. An Empirical Study of Finding Approximate Equilibria in Bimatrix Games

    OpenAIRE

    Fearnley, John; Igwe, Tobenna Peter; Savani, Rahul

    2015-01-01

    While there have been a number of studies about the efficacy of methods to find exact Nash equilibria in bimatrix games, there has been little empirical work on finding approximate Nash equilibria. Here we provide such a study that compares a number of approximation methods and exact methods. In particular, we explore the trade-off between the quality of approximate equilibrium and the required running time to find one. We found that the existing library GAMUT, which has bee...

  18. Finding Maximal Pairs with Bounded Gap

    DEFF Research Database (Denmark)

    Brodal, Gerth StØlting; LyngsØ, Rune B.

    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.

  19. Mental Findings in Trauma Victims

    Directory of Open Access Journals (Sweden)

    ?smail Özgür CAN

    2013-09-01

    Full Text Available Introduction: In medico-legal evaluation of trauma patients, the bio-psychological effects of the trauma and the severity of the injuries require to be evaluated. In this study, assuming the fact that psychiatric assessment are not taken into consideration in physical trauma cases, we have planned to bring up the presence of psychological trauma in our medico-legally evaluated patients due to different types of traumas and review the mental findings and diagnoses in trauma victims.Methods: We retrospectively analyzed the hospital records of 1975 patients aged 18 years or older who presented to the Department of Forensic Medicine at Dokuz Eylul University School of Medicine for medico-legal evaluation between 1999 and 2009. Psychiatric assessment was performed in 142 patients by Consultation and Liaison Psychiatry Section of the university hospital. Data contained in medico-legal reports and patient records were then examined with respect to patients’ age, gender, nature of traumatic events, psychiatric diagnoses, descriptive characteristics of patients, severity of trauma, and past history of mental disorder and trauma experience. Results of the medico-legal evaluations were also analyzed.Results: Of the 142 patients, 80 (56.3% were female and their average age was 40.30±17.17 years. The most frequent traumatic events were traffic accidents (29.6% and violence-related blunt force trauma (28.9%. The distribution of foremost psychiatric diagnoses were anxiety disorders in 69 cases (48.6%, adjustment disorders in 16 cases (11.3% and mood disorders in 12 cases (8.5%. Among anxiety disorders, acute stress disorder (n=39 and post-traumatic stress disorder (PTSD (n=27 were the most accounted ones. In 27 cases of the 142, it was determined that, psychiatric symptoms and findings did not cover the diagnostic criteria. Being diagnosed as having a psychiatric disorder did not significantly associated with traumatic experiences, comorbidity, marriage status, education level, and lack of health insurance. Conclusion: We assume that, the presence of a psychological trauma is crucial to be introduced not only for the health benefit but also for legal rights of the patient. The necessity of considering merely the international diagnostic criteria in determining the existence of psychiatric trauma and its severity level can bring forth some difficulties in medico-legal evaluation. (Archives of Neuropsychiatry 2012; 49: 230-236Conflict of interest: The authors report ed no conflict of interest related to this article

  20. Correlation of Imaging Findings with Pathologic Findings of Sclerosing Adenosis

    Energy Technology Data Exchange (ETDEWEB)

    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

  1. Oral tuberculosis: unusual radiographic findings

    OpenAIRE

    Sansare, K; Gupta, A; Khanna, V.; Karjodkar, F

    2011-01-01

    Oral tuberculosis and its radiographic findings are not commonly encountered in an oral and maxillofacial radiology practice. Literature has occasional mention of the radiographic findings of oral tuberculosis, which are still ambiguous. When affected, it is manifested majorly in the oral mucosa and rarely in the jaw bones. Here, we report certain unusual radiographic findings of oral tuberculosis which have been rarely mentioned in the literature. Four illustrative cases describe bony resorp...

  2. CT findings of infant epilepsy

    International Nuclear Information System (INIS)

    CT diagnosis of infantile epilepsy was evaluated. High incidence of abnormal CT findings in infantile spasms and Lennox-Gastaut syndrome was same as in other reports. Comparison between CT findings and neurological complications and that between CT findings and electroencephalogram findings revealed a stronger relationship existing in the former. This suggested that CT is more useful as a measure to detect underlying diseases which are due to organic change of the brain to cause epilepsy, rather than as that to disclose epileptic primary lesions of functional change. (Ueda, J.)

  3. Isolated perihepatic tuberculosis: imaging findings

    International Nuclear Information System (INIS)

    Aim: To review the imaging findings of isolated perihepatic tuberculosis without coexistent active tuberculosis elsewhere in the body. Materials and methods: Over a 9-year period, six patients with histopathologically proven perihepatic tuberculosis without simultaneous active tuberculosis elsewhere in the body were included in this study. Two radiologists retrospectively evaluated in consensus the location (right, left, or both perihepatic spaces), size (maximum diameter), morphology (ovoid or round), number, attenuation (low-, iso-, or high-attenuation compared with the adjacent liver parenchyma), and the presence or absence of contrast enhancement of the lesions on computed tomography (CT), and echogenicity (low-, iso-, or high-echogenicity compared with the adjacent liver parenchyma) of the lesions on ultrasonography. Results: On CT, an isolated perihepatic lesion was located in the right perihepatic space in five patients, whereas three lesions were located in both perihepatic spaces in the remaining patient. The mean maximum diameter of the isolated perihepatic tuberculosis lesions was 29.7 mm. Isolated perihepatic tuberculosis appeared as an ovoid-shaped, homogeneous, and low-attenuating (n = 5) or high-attenuating (n = 1) lesion relative to the liver. There was peripheral rim enhancement of the lesion in two patients. On ultrasonography, isolated perihepatic tuberculosis was revealed as a homogeneous, low-echoic (n = 5) or iso-echoic (n = 1) lesion relative to the liver. Conclusion: Although various inflammatory or malignant lesions can be located in the perihepatic space, isolated perihepatic tuberculosis appears an ovoid-shaped, homogeneous, and low-attenuating or low-echoic lesion compared with the liver parenchyma on CT or ultrasonography

  4. The multidimensional evaluation and treatment of anxiety in children and adolescents: rationale, design, methods and preliminary findings / Avaliação multidimensional e tratamento da ansiedade em crianças e adolescentes: marco teórico, desenho, métodos e resultados preliminares

    Scientific Electronic Library Online (English)

    Giovanni Abrahão, Salum; Luciano Rassier, Isolan; Vera Lúcia, Bosa; Andrea Goya, Tocchetto; Stefania Pigatto, Teche; Ilaine, Schuch; Jandira Rahmeier, Costa; Marianna de Abreu, Costa; Rafaela Behs, Jarros; Maria Augusta, Mansur; Daniela, Knijnik; Estácio Amaro, Silva; Christian, Kieling; Maria Helena, Oliveira; Elza, Medeiros; Andressa, Bortoluzzi; Rudineia, Toazza; Carolina, Blaya; Sandra, Leistner-Segal; Jerusa Fumagalli de, Salles; Patrícia Pelufo, Silveira; Marcelo Zubaran, Goldani; Elizeth, Heldt; Gisele Gus, Manfro.

    2011-06-01

    Full Text Available OBJETIVO: o objetivo deste estudo é descrever o desenho, os métodos e as características amostrais da Avaliação Multidimensional e Tratamento da Ansiedade em Crianças e Adolescentes - Projeto PROTAIA. MÉTODO: Escolares entre 10 e 17 anos de todas as escolas pertencentes à área de abrangência da unid [...] ade de atenção primária do Hospital de Clínicas de Porto Alegre foram incluídos no projeto. O projeto compreende cinco fases: 1) triagem comunitária; 2) diagnóstico psiquiátrico; 3) avaliação multidimensional, incluindo fatores ambientais, neuropsicológicos, nutricionais e marcadores biológicos; 4) tratamento; e 5) fase translacional. RESULTADOS: Um total de 2.457 sujeitos foram triados para transtornos de ansiedade na comunidade. Dos indivíduos que compareceram à avaliação diagnóstica, 138 foram detectados com ao menos um transtorno de ansiedade (excluindo fobia específica) e 102 indivíduos sem nenhum transtorno de ansiedade. Dentre os casos de ansiedade, o transtorno de ansiedade generalizada (n = 95; 68,8%), transtorno de ansiedade social (n = 57; 41,3%) e o transtorno de ansiedade de separação (n = 49; 35,5%) foram os mais frequentes. CONCLUSÃO: O projeto PROTAIA é um projeto de pesquisa promissor que pode contribuir para o entendimento da relação entre transtornos de ansiedade e fenótipos relacionados à ansiedade com vários fatores de risco, tanto genéticos quanto ambientais. Abstract in english OBJECTIVE: This study aims to describe the design, methods and sample characteristics of the Multidimensional Evaluation and Treatment of Anxiety in Children and Adolescents - the PROTAIA Project. METHOD: Students between 10 and 17 years old from all six schools belonging to the catchment area of th [...] e Primary Care Unit of Hospital de Clínicas de Porto Alegre were included in the project. It comprises five phases: (1) a community screening phase; (2) a psychiatric diagnostic phase; (3) a multidimensional assessment phase evaluating environmental, neuropsychological, nutritional, and biological factors; (4) a treatment phase, and (5) a translational phase. RESULTS: A total of 2,457 subjects from the community were screened for anxiety disorders. From those who attended the diagnostic interview, we identified 138 individuals with at least one anxiety disorder (apart from specific phobia) and 102 individuals without any anxiety disorder. Among the anxiety cases, generalized anxiety disorder (n = 95; 68.8%), social anxiety disorder (n = 57; 41.3%) and separation anxiety disorder (n = 49; 35.5%) were the most frequent disorders. CONCLUSION: The PROTAIA Project is a promising research project that can contribute to the knowledge of the relationship between anxiety disorders and anxiety-related phenotypes with several genetic and environmental risk factors.

  5. The multidimensional evaluation and treatment of anxiety in children and adolescents: rationale, design, methods and preliminary findings Avaliação multidimensional e tratamento da ansiedade em crianças e adolescentes: marco teórico, desenho, métodos e resultados preliminares

    Directory of Open Access Journals (Sweden)

    Giovanni Abrahão Salum

    2011-06-01

    Full Text Available OBJECTIVE: This study aims to describe the design, methods and sample characteristics of the Multidimensional Evaluation and Treatment of Anxiety in Children and Adolescents - the PROTAIA Project. METHOD: Students between 10 and 17 years old from all six schools belonging to the catchment area of the Primary Care Unit of Hospital de Clínicas de Porto Alegre were included in the project. It comprises five phases: (1 a community screening phase; (2 a psychiatric diagnostic phase; (3 a multidimensional assessment phase evaluating environmental, neuropsychological, nutritional, and biological factors; (4 a treatment phase, and (5 a translational phase. RESULTS: A total of 2,457 subjects from the community were screened for anxiety disorders. From those who attended the diagnostic interview, we identified 138 individuals with at least one anxiety disorder (apart from specific phobia and 102 individuals without any anxiety disorder. Among the anxiety cases, generalized anxiety disorder (n = 95; 68.8%, social anxiety disorder (n = 57; 41.3% and separation anxiety disorder (n = 49; 35.5% were the most frequent disorders. CONCLUSION: The PROTAIA Project is a promising research project that can contribute to the knowledge of the relationship between anxiety disorders and anxiety-related phenotypes with several genetic and environmental risk factors.OBJETIVO: o objetivo deste estudo é descrever o desenho, os métodos e as características amostrais da Avaliação Multidimensional e Tratamento da Ansiedade em Crianças e Adolescentes - Projeto PROTAIA. MÉTODO: Escolares entre 10 e 17 anos de todas as escolas pertencentes à área de abrangência da unidade de atenção primária do Hospital de Clínicas de Porto Alegre foram incluídos no projeto. O projeto compreende cinco fases: 1 triagem comunitária; 2 diagnóstico psiquiátrico; 3 avaliação multidimensional, incluindo fatores ambientais, neuropsicológicos, nutricionais e marcadores biológicos; 4 tratamento; e 5 fase translacional. RESULTADOS: Um total de 2.457 sujeitos foram triados para transtornos de ansiedade na comunidade. Dos indivíduos que compareceram à avaliação diagnóstica, 138 foram detectados com ao menos um transtorno de ansiedade (excluindo fobia específica e 102 indivíduos sem nenhum transtorno de ansiedade. Dentre os casos de ansiedade, o transtorno de ansiedade generalizada (n = 95; 68,8%, transtorno de ansiedade social (n = 57; 41,3% e o transtorno de ansiedade de separação (n = 49; 35,5% foram os mais frequentes. CONCLUSÃO: O projeto PROTAIA é um projeto de pesquisa promissor que pode contribuir para o entendimento da relação entre transtornos de ansiedade e fenótipos relacionados à ansiedade com vários fatores de risco, tanto genéticos quanto ambientais.

  6. Finding Maximal Pairs with Bounded Gap

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Lyngsø, Rune B.; Pedersen, Christian N. S.; Stoye, Jens

    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...

  7. 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

    Science.gov (United States)

    O'Dea, Angela; Tierney, Marie; McGuire, Brian E.; Newell, John; Glynn, Liam G.; Gibson, Irene; Noctor, Eoin; Danyliv, Andrii; Connolly, Susan B.; Dunne, Fidelma P.

    2015-01-01

    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. PMID:26347894

  8. Finding Anomalous Periodic Time Series: An Application to Catalogs of Periodic Variable Stars

    CERN Document Server

    Rebbapragada, Umaa; Brodley, Carla E; Alcock, Charles; 10.1007/s10994-008-5093-3

    2009-01-01

    Catalogs of periodic variable stars contain large numbers of periodic light-curves (photometric time series data from the astrophysics domain). Separating anomalous objects from well-known classes is an important step towards the discovery of new classes of astronomical objects. Most anomaly detection methods for time series data assume either a single continuous time series or a set of time series whose periods are aligned. Light-curve data precludes the use of these methods as the periods of any given pair of light-curves may be out of sync. One may use an existing anomaly detection method if, prior to similarity calculation, one performs the costly act of aligning two light-curves, an operation that scales poorly to massive data sets. This paper presents PCAD, an unsupervised anomaly detection method for large sets of unsynchronized periodic time-series data, that outputs a ranked list of both global and local anomalies. It calculates its anomaly score for each light-curve in relation to a set of centroids...

  9. CT findings of pulmonary aspergillosis

    International Nuclear Information System (INIS)

    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

  10. Chest radiographic findings of leptospirosis

    Energy Technology Data Exchange (ETDEWEB)

    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.

  11. Chest radiographic findings of leptospirosis

    International Nuclear Information System (INIS)

    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.

  12. Computer Vision Tools for Finding Images and Video Sequences.

    Science.gov (United States)

    Forsyth, D. A.

    1999-01-01

    Computer vision offers a variety of techniques for searching for pictures in large collections of images. Appearance methods compare images based on the overall content of the image using certain criteria. Finding methods concentrate on matching subparts of images, defined in a variety of ways, in hope of finding particular objects. These ideas…

  13. MRI findings in the painful hemiplegic shoulder

    International Nuclear Information System (INIS)

    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.

  14. HEMATOLOGIC FINDINGS IN OPERATING ROOM STAFFS

    Directory of Open Access Journals (Sweden)

    H SOLTANI

    2000-03-01

    Full Text Available Introduction. Long term exposure to trace amounts of anesthetic vapors and gases may produce hematologic and hepatic disorders in human. Since operating room (OR staffs are exposed to these agents, we decided to study their hematopoietic and hepatic systems in comparison with ordinary ward staffs. Methods. Seventy staffs from OR were compared with a matched similar number of ward staffs about their hematologic and hepatic laboratory findings in a historical cohort study. Findings. Mean of leukocyte and platelet counts were significantly lower in OR staffs, but in normal range. Mean of monocyte count was significantly higher in OR staffs. No significant differences were found between two groups for other hepatic and hematologic tests. Fatigue and headache were reported in OR staffs more than others. Conclusion. These findings may warn a risk to OR staffs but, it is not clear and requires further controlled studies.

  15. MRI findings in the painful hemiplegic shoulder

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Cystic intrapulmonary lymphangioma: HRCT findings

    International Nuclear Information System (INIS)

    We report a rare case of cystic intrapulmonary lymphangioma involving the left lung, which presented with pneumothorax and respiratory distress in a 6-month-old infant. Chest radiographs showed a multicystic lesion in the left lung mimicking the features of congenital cystic adenomatoid malformation of the lung. The lesion appeared on high-resolution CT (HRCT) as a multiseptate, air-filled cystic lesion in the left hilar area. Associated HRCT findings were thickening of interlobular septa and bronchovascular bundles in the left lung and the presence of peripheral pulmonary vessels within cystic lesions in the apex of the left lung. HRCT findings correlated well with histopathologic findings. We suggest that these associated findings may be helpful in distinguishing this condition from other cystic lung diseases and that this entity should be included in the differential diagnosis of multicystic lung lesions. (orig.)

  17. Finding an Eye Care Professional

    Science.gov (United States)

    ... 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” ...

  18. A Family Finds Its Way

    Science.gov (United States)

    ... Cover Story: Traumatic Brain Injury A Family Finds Its Way Past Issues / Fall 2008 Table of Contents ... spoke recently with NIH MedlinePlus ' Christopher Klose. At its heart, TBI, hearing loss, any health condition is ...

  19. Roentgen findings in cheirolumbar dysostosis

    International Nuclear Information System (INIS)

    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.)

  20. Comparative study between the proposed shape independent clustering method and the conventional methods (K-means and the other

    Directory of Open Access Journals (Sweden)

    Kohei Arai

    2013-07-01

    Full Text Available Cluster analysis aims at identifying groups of similar objects and, therefore helps to discover distribution of patterns and interesting correlations in the data sets. In this paper, we propose to provide a consistent partitioning of a dataset which allows identifying any shape of cluster patterns in case of numerical clustering, convex or non-convex. The method is based on layered structure representation that be obtained from measurement distance and angle of numerical data to the centroid data and based on the iterative clustering construction utilizing a nearest neighbor distance between clusters to merge. Encourage result show the effectiveness of the proposed technique.

  1. Global optimization for track finding

    International Nuclear Information System (INIS)

    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.)

  2. Finding Lines under Bounded Error

    OpenAIRE

    Breuel, Thomas M.

    1993-01-01

    A new algorithm for finding straight lines in images under a bounded error model is described. The algorithm is based on a hierarchical and adaptive subdivision of the space of line parameters. It measures errors in image space and thereby guarantees that no solution satisfying the given error bounds will be lost. The algorithm can find interpretations of all the lines in the image that satisfy the constraint that each image feature supports at most one line hypothesis. It can be extended to ...

  3. Radiologic findings of granulomatous mastitis

    International Nuclear Information System (INIS)

    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

  4. Radiologic findings of granulomatous mastitis

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. Computed tomographic findings of benign retroperitoneal tumors

    International Nuclear Information System (INIS)

    We have reviewed the computed tomographic (CT) findings of 8 cases of benign retroperitoneal tumors with histological proof. Two teratomas, two schwannomas, and one each of epidermoid cyst, simple cyst, bronchogenic cyst, and cystic lymphangioma were included. The most common CT appearance of these tumors was the solitary, round, well-demarcated, relatively low density mass. Capsule or calcification was demonstrated in some. CT is a highly valuable non-invasive examination method for a diagnosis of a benign retroperitoneal tumor. (author)

  6. Gene finding in the chicken genome

    OpenAIRE

    Antonarakis Stylianos E; Rogers Jane; Wyss Carine; Shteynberg David D; Huckle Elizabeth J; Parra Genis; Flicek Paul; Camara Francisco; Bye Jacqueline M; Castelo Robert; Reymond Alexandre; Eyras Eduardo; Birney Ewan; Guigo Roderic; Brent Michael R

    2005-01-01

    Abstract Background Despite the continuous production of genome sequence for a number of organisms, reliable, comprehensive, and cost effective gene prediction remains problematic. This is particularly true for genomes for which there is not a large collection of known gene sequences, such as the recently published chicken genome. We used the chicken sequence to test comparative and homology-based gene-finding methods followed by experimental validation as an effective genome annotation metho...

  7. Finding Regression Outliers With FastRCS

    OpenAIRE

    Vakili, Kaveh; Schmitt, Eric

    2013-01-01

    The Residual Congruent Subset (RCS) is a new method for finding outliers in the linear regression setting. Like many other outlier detection procedures, RCS searches for a subset which minimizes a criterion. The difference is that the new criterion was designed to be insensitive to the outliers. RCS is supported by FastRCS, a fast regression and affine equivariant algorithm which we also detail. Both an extensive simulation study and two real data applications show that Fast...

  8. Imaging Finding in 222 Patients with Vestibular

    OpenAIRE

    A. Zahiri

    2008-01-01

    Background/Objective: Vestibular Schwannoma is the most common cranial schwannoma with gradually produce sensorineural deafness. In this study we observed the effect of Gamma Knife therapy for control of this type of schwannoma."nPatients and Methods: We observed imaging findings of 250 patients with vestibular schwannoma from September 2003 to October 2007. We performed the Gamma Knife with C model (Elekta Company) for the treatment and control of the tumor."nResults: The minimum a...

  9. Intrauterine Devices Penetrated and Migrated: CT Findings

    International Nuclear Information System (INIS)

    Intrauterine devices have been used for over 40 years, and they constitute the most widely accepted method of contraception among women because of the low rates of complications and low cost. Although uncommon, with the growing use of multidetector CT penetrated and migrated intrauterine devices have become a more common incidental finding. In some cases, intrauterine devices migrate to adjacent viscera, in particular the bladder and bowel and may give rise to symptoms. Consequently tomographic localization and characterization are essential for treatment planning.

  10. Finding Flow Experience in Music Activity

    OpenAIRE

    Dewi Sartika; Saraya Ikramina Husna

    2014-01-01

    This research is aim to describe how one finding flow experience in his music activity, experiencing flow and feeling the impact of flow experience to his music career and life. The research method used is qualitative, intrinsic study case. The participants are two famous jazz musicians in Bandung, West Java, Indonesia. Data collecting used are in-depth interview, participant observation and document. The result shows that participant who has environment support especially from his music teac...

  11. Skin Findings in Renal Transplantation Patients

    Directory of Open Access Journals (Sweden)

    Demet Kartal

    2013-03-01

    Full Text Available Objective: It was aimed to identify skin findings those were seen in patients who undergone renal transplantation. Methods: Patients who have been followed in Erciyes University Nephrology Hospital renal transplantation outpatient clinic were included in the study. They were evaluated for dermatologic findings during routine controls. Age, gender, transplantation date, identity of organ donor, history of medications, dermatological history and dermatological findings during examination were recorded. Biopsy was performed when needed. Results: In total 94 patients, 25 female (26.6% and 69 male (73.4%, were recruited to the study. Mean age was 36±10 years. The most frequent skin finding was drug-related acne (n=20. Most common infectious disease was verruca (n=17. There were viral disease other than verruca such as herpes zoster (n=3, superficial mycosis such as onychomycosis (n=5, tinea versicolor, tinea pedis and bacterial skin disease (n=2, and paronychia (n=1 and pre-malign lesions such as actinic cheilitis and bowenoid papulosis. Besides these, stria (n=3, kserosis (n=2, cornu cutaneum, café-au-lait spots, sebaceous hyperplasia and seborrheic dermatitis, skin tag, hypertrichosis, unguis incarinatus and calcinosis were other skin findings those were seen. No malign skin lesion was observed in any of patients. Conclusion: Miscellaneous skin lesions should develop in patients those undergone renal transplantation due to long-term utilization of various immunosuppressive drugs.

  12. Intramammary incidental findings on staging computer tomography

    Energy Technology Data Exchange (ETDEWEB)

    Surov, Alexey, E-mail: alex.surow@medizin.uni-halle.de [Department of Radiology, Martin-Luther-University Halle-Wittenberg, Ernst-Grubestr. 40, 06097 Halle (Germany); Fiedler, Eckhard [Department of Dermatology, Martin-Luther-University Halle-Wittenberg, Ernst-Grubestr. 40, 06097 Halle (Germany); Wienke, Andreas [Department of Medical Statistics, Martin-Luther-University Halle-Wittenberg, Ernst-Grubestr. 40, 06097 Halle (Germany); Holzhausen, Hans-Jürgen [Department of Pathology, Martin-Luther-University Halle-Wittenberg, Ernst-Grubestr. 40, 06097 Halle (Germany); Spielmann, Rolf-Peter; Behrmann, Curd [Department of Radiology, Martin-Luther-University Halle-Wittenberg, Ernst-Grubestr. 40, 06097 Halle (Germany)

    2012-09-15

    Purpose: Incidental findings are a common feature in computer tomographic examinations of the chest. Breast incidentalomas, however, were described only sporadically. The purpose of this study was to evaluate retrospectively incidental breast findings and to compare radiological features of benign and malignant breast lesions. Materials and methods: From January 2006 to December 2010 a total of 8105 computer tomographic examinations were performed at our institution. In 89 patients incidental breast lesions were diagnosed. 64 of the identified patients were referred for further clinical, radiological, and hystopathological examination. All patients were female with a median age of 62 years, range 39–82 years. Results: A total of 98 breast lesions were identified in the 64 patients. The mean size was 12.0 ± 8.0 mm. Primary breast carcinoma was identified in 9, breast metastases in 27, and benign findings in 28 patients. Malignant lesions demonstrated more often marked enhancement and showed a higher density compared with benign lesions. Benign findings were more often lobular in shape and had spiculated margins. Most of the breast metastases were round or oval in shape with circumscribed margins and marked homogenous enhancement. There was no significant difference between the breast cancer and benign findings groups in the characteristics of the lesions. Conclusion: The breast is a very important region and should be carefully evaluate on chest CT. There are no certain radiological criteria to differentiate between malignant and benign breast lesions on CT. Therefore all breast incidentalomas should be evaluated by further radiological/histological investigations.

  13. Intramammary incidental findings on staging computer tomography

    International Nuclear Information System (INIS)

    Purpose: Incidental findings are a common feature in computer tomographic examinations of the chest. Breast incidentalomas, however, were described only sporadically. The purpose of this study was to evaluate retrospectively incidental breast findings and to compare radiological features of benign and malignant breast lesions. Materials and methods: From January 2006 to December 2010 a total of 8105 computer tomographic examinations were performed at our institution. In 89 patients incidental breast lesions were diagnosed. 64 of the identified patients were referred for further clinical, radiological, and hystopathological examination. All patients were female with a median age of 62 years, range 39–82 years. Results: A total of 98 breast lesions were identified in the 64 patients. The mean size was 12.0 ± 8.0 mm. Primary breast carcinoma was identified in 9, breast metastases in 27, and benign findings in 28 patients. Malignant lesions demonstrated more often marked enhancement and showed a higher density compared with benign lesions. Benign findings were more often lobular in shape and had spiculated margins. Most of the breast metastases were round or oval in shape with circumscribed margins and marked homogenous enhancement. There was no significant difference between the breast cancer and benign findings groups in the characteristics of the lesions. Conclusion: The breast is a very important region and should be carefully evaluate on chest CT. There are no certain radiological criteria to differentiate between malignant and benign breast lesions on CT. Therefore all breast incidentalomas should be evaluated by further radiological/histological investigations

  14. Near-Earth objects finding them before they find us

    CERN Document Server

    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

  15. CT findings of focal organizing pneumonia: correlation with pathologic findings

    International Nuclear Information System (INIS)

    To evaluate the CT findings of focal organizing pneumonia and to correlate them with pathologic findings to help differentiating from lung cancer. We evaluated radiologic and pathologic findings of five patients with solitary pulmonary nodule which were confirmed as focal organizing pneumonia pathologically. On CT scan, focal organizing pneumonia had irregular margin contacting the pleura in all five cases. The shape of the nodules were spherical to wedge or elliptical and the size from 3.5cm to 5.5cm(average 4.2 cm) in largest diameter. On postcontrast CT scan, all nodules showed enhancement and four cases showed central low density components. Two nodules contained air within the nodule. In four cases, pleural changes such as effusion and/or focal thickening were noted. No lymphadenopathy was found in all cases. Pathologically, the enhancing portion on CT showed findings of organizing pneumonia such as granulation tissue with fibroblast proliferation in alveolar space and interstitial thickening. The central low density areas on CT were due to ischemic necrosis, abscess and exudate, transudate and infiltration of foamy histiocyte. The possibility of focal organizing pneumonia should be considered when peripherally located solitary pulmonary nodule had enhancing component with no combined lymphadenopathy on CT scan

  16. Ultrasonographic finding of trophoblastic disease

    International Nuclear Information System (INIS)

    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

  17. Ultrasonographic finding of trophoblastic disease

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyung Sik; Lee, Kyung Soo; Choi, Byung Ihn; Kim, Chu Wan [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1983-12-15

    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

  18. MR findings of cerebral palsy

    International Nuclear Information System (INIS)

    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. CT finding of cryptococcal meningitis

    International Nuclear Information System (INIS)

    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)

  20. Imaging findings of avalanche victims

    International Nuclear Information System (INIS)

    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. Imaging findings of avalanche victims

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  2. Ultrasonographic findings of ovarian cystadenoma

    International Nuclear Information System (INIS)

    The ultrasonographic findings of 49 ovarian cystadenomas were analyzed. The results were as follows. 1. The most common age group was 3rd decade and most patients (83%) belong to active reproductive period. 2. In 80% of serous cystadenoma the size of the tumor was ranged in 6-10 cm in diameter. The large tumors of 16-20 cm in diameter were mostly mucinous cystadenomas. 3. Purely cystic appearance was the most common finding (40%) of serous cystadenoma and thick linear septation with and without solid component was the most common finding (38%) of mucious cystadenoma. 4. Thick linear septation with solid component was not found in serous cystadenoma. 5. Well defined nodular projection was found in 3 cases of serous cystadenoma but not identified in mucinous cystadenoma.

  3. Benzene exposure: An overview of monitoring methods and their findings

    OpenAIRE

    Weisel, Clifford P

    2010-01-01

    Benzene has been measured throughout the environment and is commonly emitted in several industrial and transportation settings leading to widespread environmental and occupational exposures. Inhalation is the most common exposure route but benzene rapidly penetrates the skin and can contaminant water and food resulting in dermal and ingestion exposures. While less toxic solvents have been substituted for benzene, it still is a component of petroleum products, including gasoline, and is a trac...

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

    OpenAIRE

    Dubljanin Eleonora; Džami? A.M.; Mitrovi? Sanja; Arsi?-Arsenijevi? Valentina; ?olovi?-?alovski Ivana

    2014-01-01

    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. Isolat...

  5. Research on Interest in Science: Theories, Methods, and Findings

    Science.gov (United States)

    Krapp, Andreas; Prenzel, Manfred

    2011-01-01

    This article presents an overview of interest research and describes the theoretical and methodological background for the assessment of interest in science in large-scale assessments like the "Programme for International Student Assessment" (PISA). The paper starts with a short retrospective on the history of interest, bringing out theoretical…

  6. CT findings of the thymus

    International Nuclear Information System (INIS)

    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.

  7. Fucosidosis: MRI and MRS findings

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  8. CT findings of tracheobronchial tuberculosis

    International Nuclear Information System (INIS)

    Tracheobronchial tuberculosis is the tuberculous affection of tracheobronchial wall mainly due to direct implantation of infected sputum through airway. When inflammation extends deeply into the bronchial mucosa, causing ulceration and necrosis, healing can occur with fibrosis and result in bronchial stenosis. There have been many reports of simple chest findings and bronchographic findings about tracheobronchial tuberculosis. But there is no report about CT findings of tracheobronchial tuberculosis. We reviewed and analysed CT findings of 15 cases of tracheobronchial tuberculosis which were examined during the period from January 1987 to August 1989. The diagnosis was based on bronchoscopic biopsy (5), positive sputum, AFB (5), or previous antituberculous medication with typical bronchoscopic finding (5). All 15 patients were studied with a GE-9800 scanner after injection of intravenous contrast media injection. The results were as follows. 1. Of the 15 cases, 13 cases were female and 2 cases were male. Most patients were female in their twenties or thirties. 2. The CT findings of endobronchial lesion are luminal narrowing in 15, luminal obstruction in 6, increased wall thickness in 9, wall enhancement in 2, surrounding fat plane obliteration in 7. 3. CT and bronchoscopy, equally detected bronchial lesions in 8 cases. CT was superior in 4 cases and bronchoscopy was superior in 2 cases. 4. The most frequently affected site was left main bronchus (8), followed by trachea (4), right main bronchus (4), right bronchus intermedius (4), RUL bronchus (3), LUL bronchus (3), LLL bronchus (3), RML bronchus (1), RLL bronchus (1). 5. There were 8 cases of surrounding lymphadenopathy and 7 cases of surrounding calcified lymph node. Mainly right para tracheal and tracheobronchial lymph node enlargement were observed. 6. The findings of parenchymal lesion were ill-defined nodule in 10, ateletasis in 9, bronchiectasis in 8, emphysema in 7, consolidation in 5 and cavity in 2. No parenchymal lesion observed in 1 case. Tracheobronchial stenosis, involving concentrically and long segment, in a relatively young female patient without visible mass around the stenotic segment are the typical findings of tracheobronchial tuberculosis

  9. Peak finding using biorthogonal wavelets

    International Nuclear Information System (INIS)

    The authors show in this paper how they can find the peaks in the input data if the underlying signal is a sum of Lorentzians. In order to project the data into a space of Lorentzian like functions, they show explicitly the construction of scaling functions which look like Lorentzians. From this construction, they can calculate the biorthogonal filter coefficients for both the analysis and synthesis functions. They then compare their biorthogonal wavelets to the FBI (Federal Bureau of Investigations) wavelets when used for peak finding in noisy data. They will show that in this instance, their filters perform much better than the FBI wavelets

  10. Wiring systems and fault finding

    CERN Document Server

    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

  11. Fucosidosis: MRI and MRS findings

    International Nuclear Information System (INIS)

    Fucosidosis is a rare, autosomal recessive lysosomal storage disease in which fucose-containing glycolipids, glycoproteins, and oligosaccharides accumulate in tissues as a consequence of ?-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.)

  12. Imaging findings in pediatric adrenocortical carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, J. [International Outreach Program, St. Jude Children' s Research Hospital, Memphis, TN (United States); Department of Radiology, Instituto Materno Infantil de Pernambuco, Recife (Brazil); Ribeiro, R.C. [International Outreach Program, St. Jude Children' s Research Hospital, Memphis, TN (United States); Department of Hematology-Oncology, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Department of Pediatrics, University of Tennessee-Memphis, Tennessee (United States); Fletcher, B.D. [International Outreach Program, St. Jude Children' s Research Hospital, Memphis, TN (United States); Department of Pediatrics, University of Tennessee-Memphis, Tennessee (United States); Department of Diagnostic Imaging, St. Jude Children' s Research Hospital, 332 N. Lauderdale St., Memphis, TN 38105 (United States); Department of Radiology, University of Tennessee-Memphis, TN (United States)

    2000-01-01

    Background. Adrenocortical carcinoma (ACC), a tumor that is rare among children, causes clinically evident hormonal disturbances. Imaging methods are used to stage disease and to plan surgical resection. Objective. To describe the findings of the various imaging methods used to evaluate ACC. Materials and methods. We reviewed the records of ten consecutive patients (mean age, 8.1 years) who presented from 1987 to 1998 with ACC. All patients underwent computed tomography (CT) scanning; five underwent magnetic resonance (MR) imaging; four underwent ultrasonography (US); and eight underwent radionuclide bone scans. Results. Seven patients presented with signs of hormonally functional tumors. Typical imaging findings consisted of a large, well-defined suprarenal tumor, containing calcifications (seven patients) with a thin capsule and central necrosis or hemorrhage (six patients). The inferior vena cava (IVC) was compressed by tumor in three patients, and ultrasonography demonstrated invasion of the IVC wall in one of these. Three patients' bone scans showed that the primary tumor took up radioactive tracer. Spread to lungs or liver or both was demonstrated in six patients. Conclusions. CT, US and MR imaging are effective methods of imaging the primary tumor. Chest CT and bone scintigraphy should be performed to detect metastases. The presence of a thin tumor capsule, a stellate central zone of necrosis, and evidence of hormonal function help distinguish ACC from neuroblastoma. (orig.)

  13. Milnacipran: recent findings in depression

    OpenAIRE

    Guest editors: Stuart Montgomery (London; UK); Mike Briley (Castres; France

    2010-01-01

    EDITORIAL FOREWORDPage 1   Milnacipran: recent findings in depression Stuart Montgomery (London, UK) and Mike Briley (Castres, France) REVIEWSPage 3   Suicidality: risk factors and the effects of antidepressants. The example of parallel reduction of suicidality and other depressive symptoms during treatment with the SNRI, milnacipran Philippe Courtet (Montpellier, France)Page 9   Treatment of patients with comorbid depres...

  14. US findings of tubal pregnancy

    International Nuclear Information System (INIS)

    Early diagnosis of ruptured and unruptured tubal pregnancy became more accurate with the introduction of transvaginal sonographic equipment. The management principle of tubal pregnancy might be changed according to the sonographic findings. The purposes of this study were to define the sonographic findings of tubal pregnancy and to determine whether it is possible to differentiate the unruptured tubal pregnancies from the ruptured ones depending on the sonographic findings. The authors investigated the sonographic findings of the surgically confirmed 25 tubal pregnancy patients. There were 22(88%) unruptured and 3(12%) ruptured tubal pregnancies. Unruptured pregnancies showed tubal ring in 8, well defined hematosalpinx in 11, and poorly defined hematosalpinxin 2 patients. Ruptured pregnancies showed tubal sac with irregular margin in 2, and ill-defined hematosalpinx in one patient. In summary, well marginated tubal ring and hematosalpinx suggested unruptured tubal pregnancy, while tubal sac with irregular margin suggested ruptured pregnancy. However, it was difficult to differentiate the unruptured tubal pregnancy from the ruptured one when hematosalpinx was ill-defined

  15. MRI findings in cranial eumycetoma

    Directory of Open Access Journals (Sweden)

    Munawwar Ahmed

    2011-01-01

    Full Text Available Cranial eumycetoma (CE due to direct inoculation of Madurella grisea into the scalp is extremely rare. We describe a case of CE caused by direct inoculation of M. grisea with the characteristic MRI findings of the "dot-in-circle" sign and a conglomeration of multiple, extremely hypointense "dots."

  16. Transfusional hemosiderosis; correlation of MR findings with clinical findings

    Energy Technology Data Exchange (ETDEWEB)

    Park, Mi Ok; Kim, Ju Heon; Jeon, Woo Jin; Lee, Sung Moon; Kim, Hong; Suh, Soo Jhi [School of Medicine, Keimyung University, Taegu (Korea, Republic of)

    1994-08-15

    Parenchymal iron deposition occurs in hemochromatosis, while iron is deposited in reticuloendothelial cells after blood transfusions(Hemosiderosis). We studied correlation between MR finding and clinical findings(serum ferritin, TSI, LFT, disease duration) of hemosiderosis. 12 patients with chronic renal failure and one patient with aplastic anemia, who have received multiple transfusion, were performed MRI with a 2.0 Tesla unit. In all of 13 patients(17 cases), the liver revealed low signal intensity equal to background noise. In 4 of 17 cases whose serum ferritin level was below 1000 ng/ml, pancreas, gastric wall, adrenal gland were involved in 1 case. In 4 cases with serum ferritin level between 1000 and 1500, pancreas was involved in 2 cases, and other organ was involved in 1 case. In 9 cases with serum ferritin level above 1500ng/ml, pancreas was involved in 9 cases, and other origin 4 cases. The MR findings are well correlated with serum ferritin level whereas the TSI, LFT, disease duration are not correlated with involved organ on MR.

  17. MDCT and virtual bronchoscopy findings of tracheabronchomegaly

    International Nuclear Information System (INIS)

    Full text: Introduction: Tracheabronchomegaly (TBM) or Mounier-Kuhn syndrome is a rare syndrome which is characteristic with bronchiectasis, recurrent respiratory tract infections with expansion of large bronchi. Respiration function test, imaging methods and bronchoscopy are used for the diagnosis. Objective and tasks: We aimed to evaluate the findings of virtual bronchoscopy and MDCT of 21 years-old male patient who has complaint of recurrent lower respiratory tract infection. Materials and methods: We perform thorax CT and virtual bronchoscopy with 320-detector multidetector computer tomography. Results: Diameter of the trachea at the carina level was 30.5 mm, in turn the diameters of the right and left main bronchi were 18 mm and 17 mm. There were moderate bronchiectasis in the middle and lower zones. Conclusion: MDCT and fiberoptic bronchoscopy have been used for the diagnosis of TBM. In such cases, virtual bronchoscopy is non invasive method for demonstrating luminal pathologies

  18. Lead arthropathy: radiographic, CT and MRI findings

    International Nuclear Information System (INIS)

    Lead arthropathy is a well-known complication of gunshot injuries with retained intra-articular bullets. Although several previous reports have discussed the radiological findings of this entity, computed tomography (CT) and magnetic resonance imaging (MRI) findings have never been described before in this setting. In this paper the authors review the imaging findings of 11 patients with lead arthropathy (1 of whom had clinical signs of lead poisoning as well), all of them studied by means of radiographs. In addition, non-enhanced CT scans were obtained in 3 patients and gadolinium-enhanced MRI in 1. Classic findings of intra-articular speckled lead deposits (occasionally with a ''lead arthrogram'' appearance), joint space narrowing and preserved bone density were found at radiographs in the great majority of cases. Furthermore, extension of intra-articular lead to adjacent tendon sheaths was observed in almost half of the patients, an observation rarely reported in the literature. CT scans and MRI, in their turn, were superior with regard to soft tissue abnormalities, accurately depicting joint effusion and the thickened synovium with lead particles embedded in it. Post-gadolinium MRI had the advantage of showing the enhancement pattern of the inflamed synovium and associated bone marrow edema pattern. Although it is not possible to establish the role of axial imaging in lead arthropathy from the small number of cases studied, this initial experience shows that both methods hold promise in this setting and may be useful, at least in selected cases. (orig.)

  19. An efficient method to improve the clustering performance for high dimensional data by Principal Component Analysis and modified K-means

    OpenAIRE

    Tajunisha; Saravanan

    2011-01-01

    Clustering analysis is one of the main analytical methods in data mining. K-means is the most popular andpartition based clustering algorithm. But it is computationally expensive and the quality of resultingclusters heavily depends on the selection of initial centroid and the dimension of the data. Several methodshave been proposed in the literature for improving performance of the k-means clustering algorithm.Principal Component Analysis (PCA) is an important approach to unsupervised dimensi...

  20. Interesting bone scans - unusual findings

    International Nuclear Information System (INIS)

    A 59-year-old female with carcinoma of the colon and known liver metastatic disease was referred for bone scan to evaluate for bone metastases. Although no bone metastases were found, there was abnormal uptake noted in the liver corresponding to a metastatic calcified lesion. The only other findings were of degenerative disease in the cervical spine, right shoulder and small joints of the hands. A 69-year-old male with carcinoma of the prostate and right side low back pain was referred for bone scan. No focal abnormalities to suggest metastatic disease were identified; findings within the cervical spine, lumber spine and knees were presumed secondary to degenerative disease. Intermittent pain persisted and the patient was referred for a repeat bone scan six months later. Previous scan findings of degenerative disease and no metastatic disease were confirmed; however, closer inspection revealed an enlarged right kidney with significant retention of tracer in the pelvicalyceal system suggesting possible obstruction. A Retrograde pyelogram was performed, and no obvious obstruction demonstrated. As bone scan findings were very suggestive of obstruction, a DTPA scan with lasix was performed showing a dilated right collecting system with no functional obstruction. Given the degree of dilation, it is possible that the patient experiences intermittent PUJ obstruction causing his symptoms. A 33-year-old male with insulin dependent diabetes mellitus and viral arthritis was referred for a bone scan. A three phase revealed increased uptake in the region of the knee and leR proximal tibia. Delayed whole body images revealed multiple focal areas of osteoblastic activity in the leR tibia. Abnormal uptake was also seen in the upper third of the leR femur. The remainder of the skeletal survey was normal. X-ray correlation of the leR tibia and femoral findings was undertaken. Combinating unilateral changes on bone scan and X-ray although very suggestive of sclerotic polyostotic fibrous dysplasia. Three cases with interesting and unusual bone scan findings assisted in further management and treatment of patients

  1. Interesting bone scans - unusual findings

    Energy Technology Data Exchange (ETDEWEB)

    Dobson, M.; Wadhwa, S.S.; Mansberg, R.; Fernandes, V.B. [Wollongong Hospital, Wollongong, NSW (Australia)

    1997-12-01

    A 59-year-old female with carcinoma of the colon and known liver metastatic disease was referred for bone scan to evaluate for bone metastases. Although no bone metastases were found, there was abnormal uptake noted in the liver corresponding to a metastatic calcified lesion. The only other findings were of degenerative disease in the cervical spine, right shoulder and small joints of the hands. A 69-year-old male with carcinoma of the prostate and right side low back pain was referred for bone scan. No focal abnormalities to suggest metastatic disease were identified; findings within the cervical spine, lumber spine and knees were presumed secondary to degenerative disease. Intermittent pain persisted and the patient was referred for a repeat bone scan six months later. Previous scan findings of degenerative disease and no metastatic disease were confirmed; however, closer inspection revealed an enlarged right kidney with significant retention of tracer in the pelvicalyceal system suggesting possible obstruction. A Retrograde pyelogram was performed, and no obvious obstruction demonstrated. As bone scan findings were very suggestive of obstruction, a DTPA scan with lasix was performed showing a dilated right collecting system with no functional obstruction. Given the degree of dilation, it is possible that the patient experiences intermittent PUJ obstruction causing his symptoms. A 33-year-old male with insulin dependent diabetes mellitus and viral arthritis was referred for a bone scan. A three phase revealed increased uptake in the region of the knee and leR proximal tibia. Delayed whole body images revealed multiple focal areas of osteoblastic activity in the leR tibia. Abnormal uptake was also seen in the upper third of the leR femur. The remainder of the skeletal survey was normal. X-ray correlation of the leR tibia and femoral findings was undertaken. Combinating unilateral changes on bone scan and X-ray although very suggestive of sclerotic polyostotic fibrous dysplasia. Three cases with interesting and unusual bone scan findings assisted in further management and treatment of patients

  2. On locating statistics in the world of finding out

    OpenAIRE

    Wild, Chris J.

    2015-01-01

    This paper attempts to situate statistics in relation to qualitative research methods and other means of "finding out". It compares and contrasts aspects of qualitative research methods and statistical inquiry and attempts to answer the question of whether and how elements of qualitative research methods should be included in statistics teaching.

  3. Social risk perception: recent findings in Spain

    International Nuclear Information System (INIS)

    The purpose of this paper is to present our main results from a survey carried out in Spain in the context of social risk perception. This survey is included in a broad project (PRISP) sponsored by the UE and the national Civil Protection Service, and carried out simultaneously in three countries: Spain, Italy and UK. The project combined qualitative and quantitative assessment methods, although only survey results are presented here. A random sample of 600 subjects from two different Spanish communities close to a COMAH chemical site was selected for the research. Main findings regarding, differential perception between both community populations, sex differences, and 'bias perception' of risks among others have been achieved. Main dimensions were obtained by multidimensional scaling and Factor Analysis. Dimensions reported here are similar to the usual findings from the psychometric paradigm. (authors)

  4. Studying Emerge : Findings from an event ethnography

    DEFF Research Database (Denmark)

    Davies, Sarah Rachael; Selin, Cynthia

    2015-01-01

    The Emerge event, held in Tempe, AZ in March 2012, brought together a range of scientists, artists, futurists, engineers and students in order to experiment with innovative methods for thinking about the future. These methodological techniques were tested through nine workshops, each of which made use of a different format; Emerge as a whole, then, offered an opportunity to study a diverse set of future-oriented engagement practices. We conducted an event ethnography, in which a team of 11 researchers collaboratively developed accounts of the practices at play within Emerge and its workshops. In this article we discuss findings from this ethnography, using our data both to describe the techniques used within Emerge and to analyse key patterns which occurred around those techniques. As we close we reflect on the implications of these findings for practice, suggesting ways in which our results can help hone the tools and techniques of future studies. © 2014 Elsevier Ltd. All rights reserved.

  5. Imaging findings of measles pneumonia in adults

    International Nuclear Information System (INIS)

    Objective: To illustrate the chest radiography and MSCT findings of measles pneumonia in adults. Methods: One hundred and sixty three measles patients underwent chest radiography, MSCT was performed in 3 of them. Measles pneumonia was confirmed in 10 patients (6.13%). Results: Eight of 10 patients had abnormal appearances in initial chest radiography. The characteristic chest radiographic findings were ground-glass opacities (n=6) and bronchial wall thickening (n=2). MSCT showed bilateral multiple ground-glass opacities in 1 patient, unilateral patchy ground-glass opacities with lobular distribution in the right upper lung in 2 patients. Conclusions: Familiarizing with radiographic and MSCT appearances of measles pneumonia in adults is very important for the differential diagnosis and appropriate management of measles pneumonia. Normal initial chest radiography cannot exclude the involvement of the lungs. (authors)

  6. Radioreklamen skal finde sine ben

    Directory of Open Access Journals (Sweden)

    Sigurd Bennike

    1989-08-01

    Full Text Available Den 1. august 1988 startede radioreklamerne i Danmark uden nævneværdig opmærksomhed fra hverken pressen eller medieforskerne. Annoncørerne, reklamebureauerne og de store radiostationer har haft lidt svært ved at finde hinanden. Og heller ikke nemt ved at finde ud af, hvem der skulle producere reklamerne og hvordan sådan nogle skal lyde på dansk. Som det indirekte fremgår af denne artikel, så er det svært at få tal ud af branchen. - Men et kvalificeret gæt lyder på, at der er omsat for mellem 20 og 40 millioner kroner på de første måneder, koncentreret på mindre end 50 af de 237 nærradiosendetilladelser. De radiostationer der vælger at sende reklamer, skal betale 10% af deres omsætning til en særlig radiofond, hvis midler deles ud til de græsrodsradioer, som ikke kan eller vil skaffe sig reklameindtægter.

  7. Ultrasonographic findings of accessory breast

    International Nuclear Information System (INIS)

    Accessory breast is an ectopic breast tissue from developmental remnants. It sometimes begins to make symptom, pain and swelling, during premenstrual period or pregnancy. For it has been known as a rear condition, it has occasionally misdiagnosed as a abnormal mass, such as lymphadenitis or hidradentis. We have analyzed 52 accessory breast tissues prospectively, to document the characteristic findings of accessory breast. In summary, the characteristic sonographic findings of accessory breast were the presence of breast tissue superficial to the axillary fascia or underlying fascia if not in axilla, resembling the patient's own breast pattern, the presence of converging appearance of dilated ducts, presence of nipple and/or areola, the obliteration of inner wall of dermis, the obliteration of subcutaneous fat layer, and the downward displacement of axillary fascia or underlying fascia if not in axilla without interruption

  8. Radiologic findings of hemophilic arthropathy

    International Nuclear Information System (INIS)

    Hemophilia is a primary disorder of coagulation complicated by spontaneous intra-articular hemorrhage. This paper is to describe and analyze the radiographic findings of involved bone and joints of hemophilic patients for past 5 years. The results were as follows: 1. Age distribution of the total 28 patients was ranging from 1 year to 42 years. 86% of patients was below the age of 20 years. 2. The incidence of joint involvement was in next order; knee joint (25), elbow joint (4), ankle joint (2), hip joint (1). 3. The radiologic findings of involved joint were characterized by irregularity of articular cortices (22), joint space change (19), soft tissue swelling (19), subchondral or intra-osseous cyst (12), periarticular osteoporosis (19), degenerative change (10), condylar enlargement (11) intercondylar notch widening (21) and flexion deformity (13)

  9. Radiologic findings of rib tumor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Seok; Choi, Byung Ihn; Im, Jung Gi [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1983-12-15

    Authors reviewed 21 cases of histologically confirmed rib tumor except metastasis and myeloma from November 1973 to December 1982 at Seoul National University Hospital. The results are as follows: 1. Major clinical findings are pain and mass. 2. Pathologic diagnosis of rib tumors are 5 cases of fibrous dysplasia, 3 chondroma, 2 osteochondroma, 2 desmoplastic fibroma, 3 chondroma, 2 osteochondroma, 2 desmoplastic fibroma, 5 osteosarcoma, 1 aneurysmal bone cyst, 1 eosinophilic granuloma, 1 cavernous hemangioma, 1 chondrosarcoma. 3. Radiologic findings are osteolytic change and cortical expansion without marginal sclerosis in fibrous dysplasia, central location, well-defined osteolytic change with marginal sclerosis and no cortical destruction in desmoplastic fibroma, cortical destruction, soft tissure mass and pleural effusion in malignant tumors.

  10. Learning as way-finding

    DEFF Research Database (Denmark)

    Dau, Susanne

    2015-01-01

    This paper is based on case study findings from studying undergraduate students’ perceptions of their navigation in a blended learning environment where different learning spaces are offered. In this paper learning is regarded as a multi-level and multi complex concept. In this regard the concept of learning used in this paper is inspired by the latest work of the Danish professor Illeris and the interwoven concept of knowledge development as revealed in the SECI-model generated by the Japanese ...

  11. Dermoscopy Findings of Pseudolymphomatous Folliculitis

    OpenAIRE

    Fujimura, Taku; Hidaka, Takanori; Hashimoto, Akira; Aiba, Setsuya

    2012-01-01

    Pseudolymphomatous folliculitis (PLF), which clinically mimicks cutaneous lymphoma, is a rare manifestation of cutaneous pseudolymphoma and cutaneous lymphoid hyperplasia. Here, we report on a 45-year-old Japanese woman with PLF. Dermoscopy findings revealed prominent arborizing vessels with small perifollicular and follicular yellowish spots and follicular red dots. A biopsy specimen also revealed dense lymphocytes, especially CD1a+ cells, infiltrated around the hair follicles. Without any a...

  12. Finding customers through social media

    OpenAIRE

    Piironen, Petra

    2011-01-01

    The research is a marketing study specialised in marketing in social media executed for Kuortane Sports Institute. The research was made as a case study concentrating on one of Kuortane Sports Institute’s centres, Kuortane High Performance Training Centre and its customer group of international javelin throwers and trainers. The aim of the study was to find answer the research question how can Kuortane High Performance Training Centre utilise social media in order to support their busines...

  13. Finding related functional neuroimaging volumes

    DEFF Research Database (Denmark)

    Nielsen, Finn Årup; Hansen, Lars Kai

    2004-01-01

    We describe a content-based image retrieval technique for finding related functional neuroimaging experiments by voxelization of sets of stereotactic coordinates in Talairach space, comparing the volumes and reporting related volumes in a sorted list. Voxelization is accomplished by convolving each coordinate with a Gaussian kernel. The scheme allows us to compare experiments represented as either lists of coordinates or volumes, and we introduce alternative entrances to databases by image-based...

  14. Finding two-dimensional peaks

    OpenAIRE

    Z. K.Silagadze

    2004-01-01

    Two-dimensional generalization of the original peak finding algorithm suggested earlier is given. The ideology of the algorithm emerged from the well known quantum mechanical tunneling property which enables small bodies to penetrate through narrow potential barriers. We further merge this ``quantum'' ideology with the philosophy of Particle Swarm Optimization to get the global optimization algorithm which can be called Quantum Swarm Optimization. The functionality of the ne...

  15. Finding and Segmenting Human Faces

    OpenAIRE

    Gu, Qing

    2008-01-01

    Human face and facial feature detection have attracted a lot of attention because of their wide applications, such as face recognition, face image database management and human-computer interaction. So it is of interest to develop a fast and robust algorithm to detect the human face and facial features. This paper is about a study of finding faces within images and segmenting the face into numbered regions which are the face-, mouth-, eyes- and hair regions respectively. In the last few years...

  16. MRI findings in bipartite patella

    Energy Technology Data Exchange (ETDEWEB)

    Kavanagh, Eoin C. [University of Pittsburgh Medical Centre, Department of Radiology, Pittsburgh, PA (United States); Zoga, Adam; Omar, Imran [Thomas Jefferson University Hospital, Department of Radiology, Philadelphia, PA (United States); Ford, Stephanie; Eustace, Stephen [Cappagh National Orthopaedic Hospital, Department of Radiology, Dublin (Ireland); Schweitzer, Mark [Hospital for Joint Disease, Orthopedic Institute, Department of Radiology, New York, NY (United States)

    2007-03-15

    Bipartite patella is a known cause of anterior knee pain. Our purpose was to detail the magnetic resonance imaging (MRI) features of bipartite patella in a retrospective cohort of patients imaged at our institution. MRI exams from 53 patients with findings of bipartite patella were evaluated to assess for the presence of bone marrow edema within the bipartite fragment and for the presence of abnormal signal across the synchondrosis or pseudarthrosis. Any other significant knee pathology seen at MRI was also recorded. We also reviewed 400 consecutive knee MRI studies to determine the MRI prevalence of bipartite patella. Of the 53 patients with bipartite patella 40 (75%) were male; 35 (66%) had edema within the bipartite fragment. Of the 18 with no edema an alternative explanation for knee pain was found in 13 (72%). Edema within the bipartite fragment was the sole finding in 26 of 53 (49%) patients. Bipartite patella was seen in 3 (0.7%) of 400 patients. In patients with bipartite patella at knee MRI, bone marrow edema within the bipartite fragment was the sole finding on knee MRI in almost half of the patients in our series. (orig.)

  17. Radiologic findings of pulmonary endometriosis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seon Bok; Lee, Eil Seong; Jung, Hae Kyoung; Kim, Uk Jung; Yi, Jeong Geun; Kang, Ik Won [Hallym Univ. College of Medicine, Seoul (Korea, Republic of); Kook, Shin Ho [Kangbuk Samsung Hospital, Seoul (Korea, Republic of); Park, Jae Sung [Soonchunhyang Univ. College of Medicine, Seoul (Korea, Republic of); Ryu, Dae Sik [Kangnung Hospital, Kangnung (Korea, Republic of)

    1998-12-01

    To describe the radiologic findings of pulmonary endometriosis. This study involved five patients with catamenial hemoptysis diagnosed as pulmonary endometriosis. All cases were diagnosed on the basis of bronchoscopic abnormalities. In one patient, endometrial glandular cells were seen on transthoracic fine needle aspiration biopsy. In three, hemoptysis ceased after Danazol treatment. The pattern, location and number of parenchymal abnormalities and the presence or absence of pleural lesion were analyzed retrospectively on plain chest radiographs (n=3D5) and CT scans(n=3D5). Follow-up study for each menstrual period was performed in two cases and changes from the initial lesion were assessed. Plain chest radiographic findings showed focal ground-glass opacity in three cases;two were in the right lung and one in the left. CT findings included ground-glass attenuation (n=3D3) and a mixed pattern of ground-glass attenuations and consolidations(n=3D2). Sites were single in four cases, and in one case, there were two; thus there were in all six lesions. Five of these were located in the right lung and subpleural region, continving to the pleura. Pleural lesion was not detected on either chest radiographs or CT scans. Follow-up CT scans (n=3D2) showed a similar lesion at the same site. In patient with repeated catamenial hemoptysis, CT may be helpful for the diagnosis of pulmonary endometriosis by exclusion of other diseases.=20.

  18. CT findings in sclerosing cholangitis

    International Nuclear Information System (INIS)

    To evaluate the ability of CT to detect findings indicative of primary sclerosing cholangitis (PSC) in the intrahepatic and extrahepatic biliary system, CT scans in 20 cases of PSC were compared with cholangiographic findings. Of 19 cases with extrahepatic duct disease demonstrated at cholangiography, CT detected abnormalities in the common hepatic or bile duct in 16 cases, including duct stenosis (n = 10), mural nodularity (n = 3), duct dilatation (n = 7), wall thickening (n = 6), and mural enhancement (n = 11). CT detected intrahepatic disease in all 20 cases with cholangiographic findings of PSC. CT abnormalities in the intrahepatic duct system included duct dilation (n = 19), duct stenosis (n = 15), pruning (n = 11), and beading (n = 7). CT was superior to cholangiography in characterizing the status of the intrahepatic duct system in 11 of 20 cases. In addition, CT was able to demonstrate signs of superimposed cholangiocarcinoma in three cases and to illustrate extrabiliary complications of PSC in 12 cases. This study showed that CT can detect abnormalities of the extrahepatic duct in the majority of patients with PSC and can more optimally characterize the status of the intrahepatic ducts

  19. Angiographic Findings in Biliary Atresia

    International Nuclear Information System (INIS)

    We present the angiographic findings of 46 patients with biliary atresia (BA). There were 25 males and 21 females, with a mean age of 22.5 months (range - 1.5 to 141 months). Hepatic and mesenteric angiography were obtained as part of a liver transplantation work-up or as part of the treatment of clinical events. All patients had a histological diagnosis of BA. The portal vein was patent in 43 patients, with a mean size of 4.1 mm, using the arterial catheter as comparison. Portal hepatopetal flow was observed in 20 patient and hepatofugal flow was observed in 21 patients. Presence of gastroesophageal varices was observed in 41 patients. The hepatic artery was enlarged in all patients. In all 46 patients studied, the intrahepatic peripheral hepatic artery branches presented with irregularities in contour, including encasement, strictures, dilatation and angulation, and images suggestive of peripheral occlusion. Angiographic vascular 'tuft-like' blush surrounding the irregular or occluded peripheral arterial segments was observed in 40 patients. The injection of Microfil (registered) in one case showed a marked vascular proliferation within the portal tract, apparently derived from arterial and portal connections, filling the entire portal space. We conclude that the presence of angiographically demonstrable perivascular arterial tufts in the periphery of the hepatic arterial circulation is a common finding in cases of BA, and may be a characteristic diagnostic angiographic finding

  20. Fibrolipomatous hamartoma: MR imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    De Maeseneer, M. [Dept. of Radiology, Univ. of California, San Diego, CA (United States); Jaovisidha, S. [Dept. of Radiology, Univ. of California, San Diego, CA (United States); Lenchik, L. [Dept. of Radiology, Univ. of California, San Diego, CA (United States); Witte, D. [Dept. of Radiology, Baptist Memorial Hospital, Memphis, TN (United States); Schweitzer, M.E. [Dept. of Radiology, Thomas Jefferson Univ. Hospital, Philadelphia, PA (United States); Sartoris, D.J. [Dept. of Radiology, Univ. of California, San Diego, CA (United States); Resnick, D. [Dept. of Radiology, Univ. of California, San Diego, CA (United States)

    1997-03-01

    Objective. To analyze the MR imaging features of fibrolipomatous hamartoma (FLH) of nerves. Design and patients. MR imaging studies from six patients (three men and three women) were retrospectively reviewed by three musculoskeletal radiologists. In four patients, a biopsy of the nerve lesion was performed. In two patients, biopsy data were unavailable and the diagnosis was based on the clinical history combined with the MR imaging findings. Results and conclusion. MR imaging demonstrated fusiform nerve enlargement that was caused by fatty proliferation and thickening of nerve bundles. Nerve bundles appeared as serpentine tubular structures, hypointense on both T1- and T2-weighted images. The degree of fatty proliferation varied among patients. In addition, significant variation in the distribution of fat along the course of the nerves was noted. In three patients, FLH followed the branching pattern of the nerves, a characteristic pathologic finding. In two patients, intramuscular fat deposition (biceps and tibialis posterior muscles) was present. MR imaging findings of FLH are typical, allowing a confident diagnosis. The variation of fatty proliferation among patients and involved nerves as well as the tendency of the abnormalities to follow the branching pattern of the nerves is well demonstrated with MR imaging. FLH may present as an isolated nerve lesion, may be associated with intramuscular fat deposition, or may occur as a feature of macrodystrophia lipomatosa (MDL). (orig.). With 5 figs., 2 tabs.

  1. Ultrasonographic findings of breast lesions

    International Nuclear Information System (INIS)

    Authors retrospectively analyzed ultrasonographic findings of 61 cases of breast lesions which were proven pathologically at Daerim St. Mary's Hospital from May 1987 to February 1990. The results were as follows : 1. Of all 61 cases, there were 27 fibroadenomas, 13 fibrocystic diseases, 11 carcinomas, 8 abscesses, 1 sclerosing adenosis, and 1 intraductal papilloma. 2. Findings suggesting benignancy were smooth contour, round or oval shape, homogeneously echolucent internal echo, echogenic boundary echo, and posterior enhancement. In the cases of abscess, the findings were rather irregular contour, strong posterior enhancement, and dirty, inhomogeneous internal echo. While irregular and lobulated shape, inhomogeneous and mixed internal echo and pectoral muscle invasion were suggested for malignancy. 3. The sensitivity was 98% and the specificity 58% in benign mass excluding abscesses, 63% and 98% in abscesses, and 55% and 98% in carcinomas. In conclusion, ultrasonography is one of the excellent imaging modality for detecting breast lesions larger than 5 mm in size, but unfortunately some of the malignant tumors simulated benignancy, thus we considered fine needle aspiration biopsy and adjunctive imaging modalities such as film mammography must be followed for better detection of breast cancer

  2. Painful Heel: MR Imaging Findings

    Directory of Open Access Journals (Sweden)

    Babak Sanei

    2010-05-01

    Full Text Available Heel pain is a common and frequently disabling clinical complaint that may be caused by a broad spectrum of osseous or soft-tissue disorders. "nThese disorders are classified on the basis of anatomic origin and predominant location of heel pain to foster a better understanding of this complaint. The disorders include plantar fascial lesions (fasciitis, rupture, fibromatosis, xanthoma, tendinous (tendonitis, tenosynovitis, osseous lesions (fractures, bone bruises, osteomyelitis, tumors, bursal lesions (retrocalcaneal bursitis, retroachilleal bursitis, tarsal tunnel syndrome, and heel plantar fat pad abnormalities. With its superior soft-tissue contrast resolution and multiplanar capability, magnetic resonance (MR imaging can help determine the cause of heel pain and help assess the extent and severity of the disease in ambiguous or clinically equivocal cases. Careful analysis of MR imaging findings and correlation of these findings with patient history and findings at physical examination can suggest a specific diagnosis in most cases. The majority of patients with heel pain can be successfully treated conservatively, but in cases requiring surgery (eg, plantar fascia rupture in competitive athletes, deeply infiltrating plantar fibromatosis, masses causing tarsal tunnel syndrome, MR imaging is especially useful in planning surgical treatment by showing the exact location and extent of the lesion

  3. CT Findings of Malarial Spleens

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Ji Yeon; Kwon, Jung Hyeok; Kim, Mi Jeong; Rho, Byung Hak; Lee, Mi Young [Keimyung University School of Medicine, Daegu (Korea, Republic of)

    2009-10-15

    The purpose of our study was to evaluate the CT findings of malarial spleens. We reviewed the patient records of 44 patients with malaria during a recent 3.5-year period and we selected 18 patients who underwent an abdominal CT scan. We retrospectively evaluated the CT findings of the malarial spleens and we compared then with those of a control group of 18 men. We analyzed the splenic size, whether or not there was mottled striped splenic enhancement during the arterial phase and the differences of splenic attenuation and the attenuation between the liver and spleen during the precontrast phase, the arterial phase and the portal phase between the two groups. In malarial patients, the spleen was enlarged in all cases (p < 0.001), and splenic attenuation and the degree of enhancement were significantly decreased during the precontrast phase, the arterial phase and the portal phase (p < 0.001). Loss of mottled striped enhancement during the arterial phase was seen in 11 cases (61.1%) (p < 0.001). The attenuation of the spleen was lower than that of the liver in 13 cases (72.2%) during the portal phase (p = 0.003) and in 1 case (5.6%) during the arterial phase (p = 1.000). Splenomegaly, decreased splenic enhancement, the lack of mottled striped enhancement during the arterial phase and lower attenuation than that of the liver during the portal phase are helpful CT findings to diagnose the malarial spleen.

  4. Finding Density Functionals with Machine Learning

    CERN Document Server

    Snyder, John C; Hansen, Katja; Müller, Klaus-Robert; Burke, Kieron

    2011-01-01

    Machine learning is used to approximate density functionals. For the model problem of the kinetic energy of non-interacting fermions in 1d, mean absolute errors below 1 kcal/mol on test densities similar to the training set are reached with fewer than 100 training densities. A predictor identifies if a test density is within the interpolation region. Via principal component analysis, a projected functional derivative finds highly accurate self-consistent densities. Challenges for application of our method to real electronic structure problems are discussed.

  5. Advanced form-finding for cable dome structures

    OpenAIRE

    LEE, Jaehong; TRAN, Hoang Chi; Lee, Kihak

    2010-01-01

    A numerical method is presented for form-finding of cable domes. The topology and the types of members are the only information that requires in this form-finding process. Dummy elements are used to transform the cable dome with supports into self-stressed system without supports. The eigenvalue decomposition of the force density matrix and the Singular value decomposition of the equilibrium matrix are performed iteratively to find the feasible sets of nodal coordinates and force den...

  6. Neurological Findings in Myeloproliferative Neoplasms

    Directory of Open Access Journals (Sweden)

    Semra Paydas

    2013-04-01

    Full Text Available Myeloproliferative neoplasms (MPN arise from genetic deficiencies at the level of pluripotent stem cells. Each of these neoplasms is a clonal stem cell disorder with specific phenotypic, genetic and clinical properties. Age is one of the most important factors in the development of symptoms and complications associated with MPNs.High white blood cell counts in chronic myelocytic leukemia also known as leukocytosis may lead to central nervous system findings. Tumors developing outside the bone marrow named as extramedullary myeloid tumors (EMMT could be detected at the initial diagnosis or during the prognosis of the disease, which may cause neurological symptoms due to pressure of leukemic cell mass on various tissues along with spinal cord. Central nervous system involvement and thrombocytopenic hemorrhage may lead to diverse neurological symptoms and findings.Transient ischemic attack and thrombotic stroke are the most common symptoms in polycythemia vera. Besides thrombosis and hemorrage, transformation to acute leukemia can cause neurological symptoms and findings. Transient ischemic attack, thrombotic stroke and specifically hemorrage can give rise to neurological symptoms similar to MPN in essential thrombocytosis.Extramedullary hematopoiesis refers to hematopoietic centers arise in organ/tissues other than bone marrow in myelofibrosis. Extramedullar hematopoietic centers may cause intracranial involvement, spinal cord compression, seizures and hydrocephalia. Though rare, extramedullary hematopoiesis can be detected in cranial/spinal meninges, paraspinal tissue and intracerebral regions. Extramedullary hematopoiesis has been reported in peripheral neurons, choroid plexus, pituitary, orbits, orbital and lacrimal fossa and in sphenoidal sinuses. [Cukurova Med J 2013; 38(2.000: 157-169

  7. MR findings of eosinophilic granuloma

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jong O; Yee, Mi Kyeung; Cho, Kil Ho [Yeungnam Univ. College of Medicine, Kyongsan (Korea, Republic of); Lee, Sung Moon [Keimyung Univ. College of Medicine, Taegu (Korea, Republic of); Lee, Young Hwan [Hyosung Catholic Univ. College of Medicine, Taegu (Korea, Republic of); Suh, Kyung Jin [Suhjoo MR Clinic, Taegu (Korea, Republic of)

    1999-06-01

    To describe the MR findings for the three phases of eosinophilic granuloma, as defined by Mirra's conventional radiographic criteria. Eighteen lesions in 14 patients with proven eosinophilic granuloma were retrospectively analyzed. Among this total, three vertebral lesions were excluded, and the remaining is were classified as early, middle, or late phase on the basis of Mirra's radiographic criteria. For each phase, we compared MR findings with regard to signal intensity, homogeneity, contrast enhancement, perilesional marrow edema, and soft tissue change. For the three vertebral lesions excluded because the application of radiographic criteria was difficult, MR findings for paravertebral soft tissue reaction and degree of cord compression were compared. Of the fifteen cases classified, eight were early phase, five were mid phase, and two were late phase. During each phase, all lesions except one, as seen on T1-weighted images(T1WI), showed iso-signal intensity. On T2WI, all lesions showed high signal intensity. Contrast study demonstrated marked contrast enhancement. Thus, no remarkable differences were found in the signal intensity degree of contrast enhancement of each phase. With regard to heterogeneity, this was demonstrated in most early phase lesions, reflecting necrosis and hemorrhage of those lesions. Soft tissue swelling was more severe during the early phase than the mid or late phase, but marrow edema was similar in each of the three phase. One of three patients with vertebraplana showed para-vertebral soft tissue swelling and cord compression, but this was not seen in the two other cases. For evalvating the extent of eosinophilic granuloma and its relationship with surrounding structures, MRI was superior to conventional radiography. During the early phase of the disease, lesions showed greater inhomogeneity and more aggressive soft tissue reaction than during the mid and late phase.The use of MRI for the evalvation of eosinophilic granuloma can help decide a therapeutic plan of action and follow up evaluation.

  8. MR findings of eosinophilic granuloma

    International Nuclear Information System (INIS)

    To describe the MR findings for the three phases of eosinophilic granuloma, as defined by Mirra's conventional radiographic criteria. Eighteen lesions in 14 patients with proven eosinophilic granuloma were retrospectively analyzed. Among this total, three vertebral lesions were excluded, and the remaining is were classified as early, middle, or late phase on the basis of Mirra's radiographic criteria. For each phase, we compared MR findings with regard to signal intensity, homogeneity, contrast enhancement, perilesional marrow edema, and soft tissue change. For the three vertebral lesions excluded because the application of radiographic criteria was difficult, MR findings for paravertebral soft tissue reaction and degree of cord compression were compared. Of the fifteen cases classified, eight were early phase, five were mid phase, and two were late phase. During each phase, all lesions except one, as seen on T1-weighted images(T1WI), showed iso-signal intensity. On T2WI, all lesions showed high signal intensity. Contrast study demonstrated marked contrast enhancement. Thus, no remarkable differences were found in the signal intensity degree of contrast enhancement of each phase. With regard to heterogeneity, this was demonstrated in most early phase lesions, reflecting necrosis and hemorrhage of those lesions. Soft tissue swelling was more severe during the early phase than the mid or late phase, but marrow edema was similar in each of the three phase. One of three patients with vertebraplana showed para-vertebral soft tissue swelling and cord compression, but this was not seen in the two other cases. For evalvating the extent of eosinophilic granuloma and its relationship with surrounding structures, MRI was superior to conventional radiography. During the early phase of the disease, lesions showed greater inhomogeneity and more aggressive soft tissue reaction than during the mid and late phase.The use of MRI for the evalvation of eosinophilic granuloma can help decide a therapeutic plan of action and follow up evaluation

  9. MRI findings in Hirayama disease

    Directory of Open Access Journals (Sweden)

    Raval Monali

    2010-01-01

    Full Text Available The objective of the study was to study the magnetic resonance imaging (MRI features of Hirayama disease on a 3 Tesla MRI scanner. Nine patients with clinically suspected Hirayama disease were evaluated with neutral position, flexion, contrast-enhanced MRI and fast imaging employing steady-state acquisition (FIESTA sequences. The spectrum of MRI features was evaluated and correlated with the clinical and electromyography findings. MRI findings of localized lower cervical cord atrophy (C5-C7, abnormal curvature, asymmetric cord flattening, loss of attachment of the dorsal dural sac and subjacent laminae in the neutral position, anterior displacement of the dorsal dura on flexion and a prominent epidural space were revealed in all patients on conventional MRI as well as with the dynamic 3D-FIESTA sequence. Intramedullary hyperintensity was seen in four patients on conventional MRI and on the 3D-FIESTA sequence. Flow voids were seen in four patients on conventional MRI sequences and in all patients with the 3D-FIESTA sequence. Contrast enhancement of the epidural component was noted in all the five patients with thoracic extensions. The time taken for conventional and contrast-enhanced MRI was about 30-40 min, while that for the 3D-FIESTA sequence was 6 min. Neutral and flexion position MRI and the 3D-FIESTA sequence compliment each other in displaying the spectrum of findings in Hirayama disease. A flexion study should form an essential part of the screening protocol in patients with suspected Hirayama disease. Newer sequences such as the 3D-FIESTA may help in reducing imaging time and obviating the need for contrast.

  10. Radiological findings of congenital megacolon

    Energy Technology Data Exchange (ETDEWEB)

    Yeon, Kyung Mo; Chung, Sung Hoon; Park, Jae Hyung [College of Medicine, Seoul National University, Seoul (Korea, Republic of)

    1980-12-15

    Congenital megacolon, known as Hirschsprung's disease, is potentially lethal cogenital anomaly due to dangerous complications if diagnosis and treatment are delayed. Early diagnosis is important because immediate successful surgical control reduces mortality and morbidity of this infantile disease and barium enema study is the most important diagnostic tool. Authors analyzed clinical and radiological findings of 41 cases of confirmed congenital megacolon during December 1978 to July 1980 at Seoul National University Hospital. Majority of the cases are male and below one year old. Majority of the cases represent abdominal distension, chronic constipation relieved by enema, no passage of meconium within 24hrs, after birth, vomitting, defication difficulty and emaciation. Cases of showing exudative enteropathy complaints diarrhea, dehydration and melena. In simple abdomen film, 25 cases show moderate degree of abdominal distention and 10 cases show markedly distended abdomen. Most frequent segmental pattern is type C (26.8%) and type B is the next (24.4%), and type A occupy 14.6%. There are one case of jejunal aganglionosis and two cases of total colonic aganglionosis. Most frequent shape of transition zone is type II (34%), and type VI is the next (24%) and type IV occupy 17%. In 82% of the cases show hypertrophy of bowel wall of dilated segment, and 85% of above cases show findings of exudative enteropathy. In 73% of the cases show exudative enteropathy. Almost of cases showing markedly distended abdomen, also have moderate to marked degree of hypertrophy of bowel wall and findings of exudative enteropathy. Three cases were taken 24hrs. delay film, show retention of the main bulk of barium.

  11. Radiological findings of congenital megacolon

    International Nuclear Information System (INIS)

    Congenital megacolon, known as Hirschsprung's disease, is potentially lethal cogenital anomaly due to dangerous complications if diagnosis and treatment are delayed. Early diagnosis is important because immediate successful surgical control reduces mortality and morbidity of this infantile disease and barium enema study is the most important diagnostic tool. Authors analyzed clinical and radiological findings of 41 cases of confirmed congenital megacolon during December 1978 to July 1980 at Seoul National University Hospital. Majority of the cases are male and below one year old. Majority of the cases represent abdominal distension, chronic constipation relieved by enema, no passage of meconium within 24hrs, after birth, vomitting, defication difficulty and emaciation. Cases of showing exudative enteropathy complaints diarrhea, dehydration and melena. In simple abdomen film, 25 cases show moderate degree of abdominal distention and 10 cases show markedly distended abdomen. Most frequent segmental pattern is type C (26.8%) and type B is the next (24.4%), and type A occupy 14.6%. There are one case of jejunal aganglionosis and two cases of total colonic aganglionosis. Most frequent shape of transition zone is type II (34%), and type VI is the next (24%) and type IV occupy 17%. In 82% of the cases show hypertrophy of bowel wall of dilated segment, and 85% of above cases show findings of exudative enteropathy. In 73% of the cases show exudative enteropathy. Almost of cases showing markedly distended abdomen, also have moderate to marked degree of hypertrophy of bowel wall and findings of exudative enteropathy. Three cases were taken 24hrs. delay film, show retention of the main bulk of barium

  12. Cholangiographic findings in ulcerative colitis

    International Nuclear Information System (INIS)

    Endoscopic retrograde cholangiography (ERC) was performed in 28 patients with hepatobiliary disease associated with ulcerative colitis. The films were reviewed and correlated with diagnoses at liver biopsy. Thirteen patients with extrahepatic as well as intrahepatic bile duct abnormalities had characteristic cholangiographic findings compatible with sclerosing cholangitis, together with cholangiocarcinoma in one patient. Six patients had intrahepatic bile duct involvement only, and the cholangiographic abnormalities differed from those of sclerosing cholangitis. In 5 of these patients cirrhosis of the liver was found at biopsy or clinically. The result indicates that in patients with hepatobiliary disease suggested in association with ulcerative colitis, ERC gives valuable information. (Auth.)

  13. MRI findings of intraocular diseases

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Makoto; Nagai, Haruhiko; Ueno, Tetsuji; Igarashi, Yasuo (Sapporo Medical Coll. (Japan)); Narazaki, Yoshikazu; Takeda, Akira

    1989-06-01

    MRI findings of intra-ocular lesion were studied on seven cases : two cases of choroidal malignant melanoma, one case of choroidal tumor, two cases of retinal detachment with vitreous hemorrhage, and two cases of choroidal detachment. Intraocular lesions were clearly visualized by T{sub 1} weighted MRI which was of great benefit in visualizing morphological changes. T{sub 2} weighted images could not visualize morphological changes very well, but had some merits in differentiating the ocular pathology. MRI was a very useful examination for intra-ocular lesions. (author).

  14. MRI findings of intraocular diseases

    International Nuclear Information System (INIS)

    MRI findings of intra-ocular lesion were studied on seven cases : two cases of choroidal malignant melanoma, one case of choroidal tumor, two cases of retinal detachment with vitreous hemorrhage, and two cases of choroidal detachment. Intraocular lesions were clearly visualized by T1 weighted MRI which was of great benefit in visualizing morphological changes. T2 weighted images could not visualize morphological changes very well, but had some merits in differentiating the ocular pathology. MRI was a very useful examination for intra-ocular lesions. (author)

  15. MR findings in peliosis hepatis

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    Saatci, I. [Dept. of Diagnostic Radiology, Hacettepe Univ. Hospital, Ankara (Turkey); Coskun, M. [Dept. of Diagnostic Radiology, Hacettepe Univ. Hospital, Ankara (Turkey); Boyvat, F. [Dept. of Diagnostic Radiology, Hacettepe Univ. Hospital, Ankara (Turkey); Cila, A. [Dept. of Diagnostic Radiology, Hacettepe Univ. Hospital, Ankara (Turkey); Guergey, A. [Dept. of Pediatric Hematology, Hacettepe Univ. Hospital, Ankara (Turkey)

    1995-02-01

    We report the MR findings of peliosis hepatis in a patient with Fanconi anemia who had been treated with anabolic androgenic steroids for 3 years. The MR examination of the upper abdomen was performed on a 0.5 T system. The signal intensity of the right lobe of the liver was diffusely increased in all sequences. Within the enlarged liver, multiple foci of brighter signal were seen involving both right and left lobes. The lesions showed contrast enhancement. A cystic cavity with an enhancing rim was seen representing a haematoma cavity. The spleen was spared the patient died of sepsis and the postmortem examination confirmed the diagnosis of peliosis hepatis. (orig.)

  16. Breast spongioma: Aunt Minnie findings

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    Baysal, Tamer [Inonu University, School of Medicine, Department of Radiology, Turgut Ozal Medical Center, Malatya (Turkey)]. E-mail: tbaysal@inonu.edu.tr; Mutlu, Deniz [Inonu University, School of Medicine, Department of Radiology, Turgut Ozal Medical Center, Malatya (Turkey); Erdogan, Ozgul [Inonu University, School of Medicine, Department of Radiology, Turgut Ozal Medical Center, Malatya (Turkey)

    2005-11-01

    Gossypiboma is a term used to refer to pseudo-tumors composed of a non-absorbable cotton matrix. Retained sponge in the breast is extremely rare in the literature. The radiologic identification of gossypiboma is difficult because of their variable appearance. But when typical radiologic appearances are present in a patient with previous breast surgery, pre-operative diagnosis of a retained surgical sponge may prevent fatal complications. We present 'Aunt Minnie' findings of gossypiboma in a patient with previous breast surgery including ultrasound (US), mammogram and computed tomography (CT)

  17. CT findings of retroperitoneal masses

    International Nuclear Information System (INIS)

    Retrospective analysis of forty one retroperitoneal masses was made with computed tomography. All cases were confirmed pathologically by operation or needle aspiration biopsy. The cases were; 14 abscesses, 2 leiomyosarcomas, 2 rhabdomyosarcomas, 2 liposarcomas, 1 undifferentiated sarcoma, 3 endodermal sinus tumors, 4 teratomas, 2 neurofibromas, 1 neurilemoma, 3 neuroblastomas, 4 malignant lymphomas, 2 malignant fibrous histiocytomas and 1 hemangiopericytoma. Tumors originated from urinary tract and pancreas were not included. Findings favor tumor rather than inflammation were; large lobulated soft tissue mass with eccentric or heterogeneous low density, thick cavity wall, disruption of fascial planes, regional lymphnode enlargement and distant metastasis

  18. Shapelets I. A Method for Image Analysis

    CERN Document Server

    Réfrégier, A

    2003-01-01

    We present a new method for the analysis of images, a fundamental task in observational astronomy. It is based on the linear decomposition of each object in the image into a series of localised basis functions of different shapes, which we call `Shapelets'. A particularly useful set of complete and orthonormal shapelets is that consisting of weighted Hermite polynomials, which correspond to perturbations around a circular gaussian. They are also the eigenstates of the 2-dimensional Quantum Harmonic Oscillator, and thus allow us to use the powerful formalism developed for this problem. Among their remarkable properties, they are invariant under Fourier transforms (up to a rescaling), leading to an analytic form for convolutions. The generator of linear transformations such as translations, rotations, shears and dilatations can be written as simple combinations of raising and lowering operators. We derive analytic expressions for practical quantities, such as the centroid (astrometry), flux (photometry) and rad...

  19. CT findings of melamine caused urinary calculi

    International Nuclear Information System (INIS)

    Objective: To analyze the CT findings of melamine induced urinary calculi. Methods: Nineteen children with a history of ingestion of melamine contaminated infant formula milk were studied, including 12 males and 7 females, age ranged from 50 days to 5 years. Results: CT demonstrated renal pelvic and ureteral stones in 13 cases, with urinary obstruction in 9 of them. The size of the stones ranged from 0.3 cm x 0.3 cm to stag-horn calculus. Tine density of the stones measured from a low of 40-70 HU up to a high of 410 HU with an average density of 160 HU. Conclusion: CT scan is an excellent modality in demonstrating urinary tract calculi caused by melamine. It is the method of choice when ultrasound examinations are equivocal. (authors)

  20. The radiologic findings of neurofibromatosis

    International Nuclear Information System (INIS)

    Neurofibromatosis, or von Recklinghausen's disease, is a hereditary, harmartomatous disorder that primarily involves neuro ectoderm and mesoderm. The estimated incidence is 1 in 2,500 to 3,000 births. The clinical features are skin manifestations such as cafe-au-lait spots, skeletal manifestations primarily involving vertebrae, central and peripheral nervous manifestations, and other associated abnormalities with increased risk of malignancy. The authors analysed the radiologic findings of 18 cases of patients with neurofibromatosis who visited Pusan Kosin Medical Center and Taegu Dongsan Medical Center during the last five years. All were proven by surgery, biopsy and other diagnostic criteria. The results obtained were as follows: 1. The male to female ratio was 11:7 and the age ranged from 11 months to 51 years. 2. All the cases fulfilled the diagnostic criteria of Crowe and associates. 3. Bone manifestations were present in 44% of the cases. The other radiologic findings were intrathoracic meningocele, bilateral acoustic neurinomas, mediastinal or chest wall mass shadows, and peripheral soft tissue masses. 4. One of the soft tissue masses was proved to be malignant.

  1. CT findings of intracranial tuberculosis

    International Nuclear Information System (INIS)

    Although the most common form of tuberculosis is pulmonary, one of the most dangerous forms is that which affects the central nervous systems. The CT is valuable in determining disease, locations and extent of brain lesions. One hundred-eight cases of intracranial tuberculosis were studied by CT in Severance and Wonju Christian Hospital from Jan. 1982 to Jun. 1986. The results are as follows: 1.The age distribution was broad from 6 months to 68 years. The incidence was the highest in the age group from 0 to 5, and the male to female ratio was 1.2 : 1. 2.The common CT findings were obliteration and abnormal enhancement of basal cisterns that were observed in 63 cases (58%) and ventricular dilatation in 56 cases (52%). The single or multiple enhancing nodules denoting tuberculomas were observed in 31 cases, that were distributed in cerebral hemisphere, brain stem or cerebellum. Eighteen cases of brain infarction were observed and most frequent site of infarction was basal ganglia (14 cases). 3.Nineteen cases showed normal findings in CT scan in spite of the intracranial tuberculosis

  2. Groove Pancreatitis: Spiral CT Findings

    International Nuclear Information System (INIS)

    To describe the spiral CT findings of groove pancreatitis, a little known entity, and to review its differential diagnosis. We present 8 cases of groove pancreatitis. or pancreatitis affecting the groove between pancreatic head, duodenum and common bile duct, all studied with spiral CT. For two cases, in which were performed cephalic duodenopancreatectomies, anatomopathological correlations were available. In the other 6 cases, radiological follow-ups of anywhere between 5 and 36 months were utilized. In all eight cases, spiral CT showed expansion and increasing density of lipids within the groove with poor contrast enhancement indicative of the fibrous nature of this pathology, and associated with cystic areas in its interior and/or the duodenal wall. the pancreatic head was unaffected in pure forms of groove pancreatitis, and hypodense areas were observed in zones of cephalic segmental enhancement. Knowledge of this little known form of chronic pancreatitis, and the radiological findings that permit its diagnosis are important for the radiologist since its differential diagnosis includes neoplasia of the peri-ampullary region. (Author) 6 refs

  3. Ultrasonographic Findings of Gallbladder Carcinoma

    International Nuclear Information System (INIS)

    The gallbladder carcinoma accounts for 1.9% of all cancer and occurs predominantly in women over 50 years of age. As a rule, it may not be detected until the lesion has become quite large and has extended to adjacent structures. Ultrasonography is a direct imaging procedure which is widely used for the diagnosis of gallbladder carcinoma. Authors analyzed sonographic findings of 24 patients with gallbladder carcinoma diagnosed at the Department of Radiology, Kangnam St. Mary's Hospital, Catholic University Medical College during the past 5 years. 1. The gallbladder carcinoma was most prevalent in the sixth decade of life with equal ration of male to female patients. 2. The ultrasonographic findings of gallbladder carcinoma were classified into four types. The mass filling or replacing the gallbladder type was seen in 11 cases(46%), the thickened gallbladder-wall type in 6 cases (25%), fungation mass type in 4 cases(17%), and mixed type with thickened gallbladder-wall and fungating mass in 3 cases(13%). 3. Gallbladder carcinoma was associated with gallstones in 50%, with dilated bile ducts in 54%, with direct invasion of adjacent liver parenchyma in 50%, and with distant metastasis to the liver in 13%

  4. Rhabdoid tumour of the kidney: imaging findings

    International Nuclear Information System (INIS)

    Background. Rhabdoid tumour of the kidney (RTK) is a rare tumour, but it is the most aggressive malignant neoplasm of the kidney in children. Objective. To analyse the radiological findings of RTK in children. Materials and methods. The clinical and radiological findings in seven children (age range 6 months to 4.7 years; median 18 months) with pathologically proven RTK were retrospectively reviewed. We analysed tumour size, tumour location, tumour margin, subcapsular haematoma, tumour necrosis, haemorrhage, calcification and lymphadenopathy. Results. Tumour size varied from 5 to 12 cm. Four tumours were located mainly in the central portion of the kidney, while three tumours were mainly sited peripherally. The margins of the tumour were ill-defined in four (57 %) of seven cases, a lobulated tumour surface was depicted in all seven (100 %), subcapsular haematoma was present in four (57 %), tumour necrosis or haemorrhage in seven (100 %), calcifications in three (43 %) and retroperitoneal lymphadenopathy in four (57 %). Conclusions. Imaging findings of RTK are subcapsular haematoma, a lobulated surface of the tumour, calcification and tumour necrosis or haemorrhage. (orig.)

  5. MRI Findings in Patients with TMJ Click

    Directory of Open Access Journals (Sweden)

    Mahrokh Imanimoghaddam

    2013-12-01

    Full Text Available Introduction: It has been shown that joint click, an initial and common finding in internal derangement (ID, respond to neither conservative treatment nor surgical intervention. This raises the question as to whether it must be treated in the absence of other pertinent signs and symptoms, so the aim of this study was to investigate and compare the MRI findings of TMJ in both normal subjects and patients with click, in order to determine the importance of click in predicting TMJ pathological changes. Methods: A total of 26 patients with clinical symptoms of disk displacement with reduction (DDwR according to RDC/TMD were compared to 14 normal subjects in terms of their MRI findings, including disk displacement, effusion, condylar osteoarthritic changes and disk deformities. Results: Out of 80 joints in total (52 affected joints in 26 patients and 28 joints in control group, 48 were shown with normal disk position in MRI whereas 28 (35% and 4 (5% were categorised as DDwR and (disk displacement without reduction DDwoR, respectively. Statistically significant correlations were established between the following pairs of variables in order: Click and disk displacement, effusion and disk displacement, disk displacement and effusion with disk deformity. Conclusion: The correlation between the presence of click and disk displacement, disk deformity and effusion emphasizes the importance of MRI for an accurate diagnosis and development of an appropriate treatment plan in these cases and shows that clinical examination is not sufficient for these purposes.

  6. Imaging Finding in 222 Patients with Vestibular

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    A. Zahiri

    2008-01-01

    Full Text Available Background/Objective: Vestibular Schwannoma is the most common cranial schwannoma with gradually produce sensorineural deafness. In this study we observed the effect of Gamma Knife therapy for control of this type of schwannoma."nPatients and Methods: We observed imaging findings of 250 patients with vestibular schwannoma from September 2003 to October 2007. We performed the Gamma Knife with C model (Elekta Company for the treatment and control of the tumor."nResults: The minimum age of our patients was 14 years and maximum age was 90 years. Twenty six patients was N.F.2, and female to male ratio was 2/1. The most common imaging finding was loss of central contrast enhancement in contrast MRI beginning after nine months after Gamma Knife. Loss of volume and cystic changes were other imaging findings and regrowth of tumor was seen in same case. After three years follow up, tumor control, tumor regression, and tumor enlargement were seen in 85%, 10%, and 5% of our patients respectively."nConclusion: Gamma Knife should be considered as a suitable treatment option for the treatment of Vestibular Schwannoma.

  7. CT findings at lupus mesenteric vasculitis

    International Nuclear Information System (INIS)

    Purpose: To describe the spectrum of early CT findings of lupus mesenteric vasculitis (LMV) and to assess the utility of CT in the management of this uncommon entity. Methods: Abdominal CT was performed within 1-4 days (average 2.2 days) of the onset of severe abdominal pain and tenderness in 15 women with systemic lupus erythematosus. Prompt high-dose i.v. corticosteroid in 11 patients after the CT diagnosis of LMV was made. CT was performed after abdominal symptoms subsided. Results: Eleven cases revealed CT features suggestive of LMV including conspicuous prominence of mesentric vessels with palisade pattern or comb-like appearance (CT comb sign) supplying focal or diffuse dilated bowel loops (n=11), ascites with slightly increased peritoneal enhancement (n=11), small bowel wall thickening (n=10) with double halo or target sign (n=8). Follow-up CT before high-dose steroid therapy revealed complete or marked resolution of the abnormal CT findings. Conclusion: CT is helpful for confirming the diagnosis of LMV, especially the comb sign which may be an early sign. Bowel ischemia due to LMV is less ominous than previously expected, and the abnormal CT findings were reversible when early diagnosis and prompt i.v. steroid therapy could be achieved. (orig.)

  8. CT findings at lupus mesenteric vasculitis

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    Ko, S.F. [Chang Gung Medical College and Memorial Hospital, Dept. of Radiology, Kaohsiung Hsien (Taiwan); Lee, T.Y. [Chang Gung Medical College and Memorial Hospital, Dept. of Radiology, Kaohsiung Hsien (Taiwan); Cheng, T.T. [Chang Gung Medical College and Memorial Hospital, Dept. of Rheumatology, Kaohsiung Hsien (Taiwan); Ng, S.H. [Chang Gung Medical College and Memorial Hospital, Dept. of Radiology, Kaohsiung Hsien (Taiwan); Lai, H.M. [Chang Gung Medical College and Memorial Hospital, Dept. of Rheumatology, Kaohsiung Hsien (Taiwan); Cheng, Y.F. [Chang Gung Medical College and Memorial Hospital, Dept. of Radiology, Kaohsiung Hsien (Taiwan); Tsai, C.C. [Chang Gung Medical College and Memorial Hospital, Dept. of Radiology, Kaohsiung Hsien (Taiwan)

    1997-01-01

    Purpose: To describe the spectrum of early CT findings of lupus mesenteric vasculitis (LMV) and to assess the utility of CT in the management of this uncommon entity. Methods: Abdominal CT was performed within 1-4 days (average 2.2 days) of the onset of severe abdominal pain and tenderness in 15 women with systemic lupus erythematosus. Prompt high-dose i.v. corticosteroid in 11 patients after the CT diagnosis of LMV was made. CT was performed after abdominal symptoms subsided. Results: Eleven cases revealed CT features suggestive of LMV including conspicuous prominence of mesentric vessels with palisade pattern or comb-like appearance (CT comb sign) supplying focal or diffuse dilated bowel loops (n=11), ascites with slightly increased peritoneal enhancement (n=11), small bowel wall thickening (n=10) with double halo or target sign (n=8). Follow-up CT before high-dose steroid therapy revealed complete or marked resolution of the abnormal CT findings. Conclusion: CT is helpful for confirming the diagnosis of LMV, especially the comb sign which may be an early sign. Bowel ischemia due to LMV is less ominous than previously expected, and the abnormal CT findings were reversible when early diagnosis and prompt i.v. steroid therapy could be achieved. (orig.).

  9. CT findings in acute small bowel diverticulitis

    International Nuclear Information System (INIS)

    Small bowel diverticulitis is a rare cause of an acute abdomen. Originating from acquired diverticula of the jejunum, less often of the ileum, or Meckel diverticulum, the symptoms are non-specific, simulating other acute inflammatory disorders, such as appendicitis, cholecystitis or colonic diverticulitis. The diagnosis of small bowel diverticulitis is solely based on radiologic findings, with computed tomography (CT) regarded as the method of choice. In recent years, a number of case reports have described the spectrum of the CT features in acute small bowel diverticulitis and its dependence on the severity of the inflammatory process. Typical findings are an inflamed diverticulum, inflammatory mesenteric infiltration, extraluminal gas collection and mural edema of adjacent small bowel loops with resultant separation of bowel loops. An enterolith is rarely found in an inflamed diverticulum. Complications include abscesses, fistulae, small bowel obstruction and free perforation with peritonitis. Small bowel diverticulitis can be a diagnostic problem if it involves the terminal ileum or Meckel's diverticulum. For preoperative confirmation of the presumed diagnosis of small bowel diverticulitis on CT, an enteroclysis for acquired diverticula or a technetium scan for Meckel's diverticulum should be performed. We present the CT findings in three patients of acute small bowel diverticulitis, two affecting the jejunum and one a Meckel's diverticulum. (orig.)

  10. Brain computed tomography findings of schizophrenia, (2)

    International Nuclear Information System (INIS)

    The relationship between brain CT findings and the total dose of antipsychotic drugs was examined in 47 cases with schizophrenia ranging from 20 to 42 years in age (31 males and 16 females). The methods of Gyldensted et al. and Okamoto et al. were modified for CT measurements. The total dose during the entire course was converted into the dose of chlorpromazine (CPZ) for each case. For comparisons with CT findings, the total dose was classified into three types each for both sexes: ''less than'' 100 g, ''less than'' 500 g and ''more than'' 500 g for the males and ''more than'' 500 g, ''less than'' 1,000 g and ''more than'' 1,000 g for the females. For similar comparisons, the same subjects were matched for the age and sex distinction, and were divided into the ''less than'' and ''more than'' groups for 500 g and 800 g, respectively. In both the matched and non-matched cases, each measurement value of the ventricular system on CT tended to be higher in the ''more than'' groups than in the ''less than'' groups. The relationship between CT findings and the total dose was nogligible. (Chiba, N.)

  11. MR findings of cyclosporine neurotoxicity

    International Nuclear Information System (INIS)

    To analyze the MR findings of cyclosporine-induced neurotoxicity in patients receiving high dose of cyclosporine and to suggest the possible pathogenetic mechanism. The cases of seven patients (2 males, 5 females;18-36 years old) who suffered seizures after receiving high-dose cyclosporine for bone marrow transplantation due to diseases such as aplastic anemia or leukemia were retrospectively reviewed. We evaluated the location and pattern of abnormal signal intensity seen on T2 weighted images, the presence of contrast enhancement, and the changes seen on follow-up MR performed at intervals of 12-30 days after initial MR in five of seven patients. We analyzed levels of blood cyclosporine and magnesium, and investigated the presence of hypertension at the sity of the seizure. Locations of the lesions were bilateral(n=3D5), unilateral(n=3D2), parietal(n=3D6), occipital(n=3D6), temporal(n=3D4), and in the frontal lobe(n=3D3). Frontal lesions showed high signal intensities in the borderline ischemic zone of the frontal lobe between the territory of the anterior and middle cerebral arteries. In six of the seven patients, cortical and subcortical areas including subcortical U-fibers were seen on T2-weighted images to be involved in the parietooccipital lobes. Only one of the seven showed high signal intensity in the left basal ganglia. All lesions showed high signal intensity on T2-weighted images, and iso to low signal intensity on T1-weighted. In five of seven patients there was no definite enhancement, but in the other two, enhancement was slight. In four of seven patients seizures occurred within high therapeutic ranges(250-450ng/ml), while others suffered such attacks at levels below the therapeutic range. After cyclospirine was administered at a reduced dosage or stopped, follow-up MR images showed the complete or near-total disappearance of the abnormal findings previously described. Only two patients had hypertension, and the others normotension. Five of the seven had hypomagnesemia(1.3-1.74mg/dl;N:1.9-3.1mg/dl). Most patients with cyclosporine neurotoxicity showed high signal intensity in the cortical and subcortical areas of the parietooccipital lobes, including subcortical U-fiber, as seen on T2 weighted images, and no abnormal enhancement after Gd-DTPA injection. These MR findings should be helpful for the diagnosis of cyclosporine neurotoxicity.=20

  12. MR findings of cyclosporine neurotoxicity

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    Yang, Po Song; Ahn, Kook Jin; Ahn, Bo Young; Jung, Hae An; Kim, Hee Je; Lee, Jae Mun [The Catholic Univ. St Mary' s Hospital, Seoul (Korea, Republic of)

    1998-12-01

    To analyze the MR findings of cyclosporine-induced neurotoxicity in patients receiving high dose of cyclosporine and to suggest the possible pathogenetic mechanism. The cases of seven patients (2 males, 5 females;18-36 years old) who suffered seizures after receiving high-dose cyclosporine for bone marrow transplantation due to diseases such as aplastic anemia or leukemia were retrospectively reviewed. We evaluated the location and pattern of abnormal signal intensity seen on T2 weighted images, the presence of contrast enhancement, and the changes seen on follow-up MR performed at intervals of 12-30 days after initial MR in five of seven patients. We analyzed levels of blood cyclosporine and magnesium, and investigated the presence of hypertension at the sity of the seizure. Locations of the lesions were bilateral(n=3D5), unilateral(n=3D2), parietal(n=3D6), occipital(n=3D6), temporal(n=3D4), and in the frontal lobe(n=3D3). Frontal lesions showed high signal intensities in the borderline ischemic zone of the frontal lobe between the territory of the anterior and middle cerebral arteries. In six of the seven patients, cortical and subcortical areas including subcortical U-fibers were seen on T2-weighted images to be involved in the parietooccipital lobes. Only one of the seven showed high signal intensity in the left basal ganglia. All lesions showed high signal intensity on T2-weighted images, and iso to low signal intensity on T1-weighted. In five of seven patients there was no definite enhancement, but in the other two, enhancement was slight. In four of seven patients seizures occurred within high therapeutic ranges(250-450ng/ml), while others suffered such attacks at levels below the therapeutic range. After cyclospirine was administered at a reduced dosage or stopped, follow-up MR images showed the complete or near-total disappearance of the abnormal findings previously described. Only two patients had hypertension, and the others normotension. Five of the seven had hypomagnesemia(1.3-1.74mg/dl;N:1.9-3.1mg/dl). Most patients with cyclosporine neurotoxicity showed high signal intensity in the cortical and subcortical areas of the parietooccipital lobes, including subcortical U-fiber, as seen on T2 weighted images, and no abnormal enhancement after Gd-DTPA injection. These MR findings should be helpful for the diagnosis of cyclosporine neurotoxicity.=20.

  13. Oral bacterial DNA findings in pericardial fluid

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    Anne-Mari Louhelainen

    2014-11-01

    Full Text Available Background: We recently reported that large amounts of oral bacterial DNA can be found in thrombus aspirates of myocardial infarction patients. Some case reports describe bacterial findings in pericardial fluid, mostly done with conventional culturing and a few with PCR; in purulent pericarditis, nevertheless, bacterial PCR has not been used as a diagnostic method before. Objective: To find out whether bacterial DNA can be measured in the pericardial fluid and if it correlates with pathologic–anatomic findings linked to cardiovascular diseases. Methods: Twenty-two pericardial aspirates were collected aseptically prior to forensic autopsy at Tampere University Hospital during 2009–2010. Of the autopsies, 10 (45.5% were free of coronary artery disease (CAD, 7 (31.8% had mild and 5 (22.7% had severe CAD. Bacterial DNA amounts were determined using real-time quantitative PCR with specific primers and probes for all bacterial strains associated with endodontic disease (Streptococcus mitis group, Streptococcus anginosus group, Staphylococcus aureus/Staphylococcus epidermidis, Prevotella intermedia, Parvimonas micra and periodontal disease (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, Fusobacterium nucleatus, and Dialister pneumosintes. Results: Of 22 cases, 14 (63.6% were positive for endodontic and 8 (36.4% for periodontal-disease-associated bacteria. Only one case was positive for bacterial culturing. There was a statistically significant association between the relative amount of bacterial DNA in the pericardial fluid and the severity of CAD (p=0.035. Conclusions: Oral bacterial DNA was detectable in pericardial fluid and an association between the severity of CAD and the total amount of bacterial DNA in pericardial fluid was found, suggesting that this kind of measurement might be useful for clinical purposes.

  14. Infratentorial oligodendrogliomas: Imaging findings in six patients

    International Nuclear Information System (INIS)

    Background: Oligodendrogliomas are primarily supratentorial tumors. However, infrequently, they can also arise from infratentorial structures. There are only limited numbers of radiological articles on the specific imaging findings of this entity. Purpose: To investigate the imaging findings of infratentorial oligodendrogliomas. Material and Methods: We retrospectively reviewed the magnetic resonance imaging (MRI) findings and clinical records of six patients with pathologically proven infratentorial oligodendrogliomas between December 1994 and April 2008. Tumor location, circumscription, signal intensity (SI), enhancement pattern, the presence of restricted diffusion, and the change of the relative cerebral blood volume (rCBV) on MRI were evaluated. Results: In total, six patients (three male, three female; mean age 65 years, range 51-75 years) were included. The pathology revealed anaplastic oligodendrogliomas in all six patients. The location was cerebellum in four patients, medulla in one patient, and fourth ventricle and tegmentum in one patient. Three of them were of the infiltrative type, and the other three of the mass-forming type. The solid component of the tumors showed high SI (n=6) on FLAIR and T2-weighted images, and low (n=5) or iso (n=1) SI on T1-weighted images. All infiltrative lesions showed multifocal patchy enhancement, and mass-forming lesions showed heterogeneous enhancement (n=2) and diffuse homogeneous enhancement (n=1). Three patients had restricted diffusion, and one had leptomeningeal seeding. There was markedly increased rCBV on perfusion-weighted image (PWI) in one patient. Calcification or hemorrhage was not found. Tumor progression after operation, radiation therapy, gamma-knife surgery, or chemotherapy developed in five patients. Conclusion: Although infratentorial oligodendrogliomas did not show characteristic imaging findings, there was a tendency toward multifocal heterogeneous enhancement and absent or mild mass effect of infiltrative lesions. Infratentorial oligodendrogliomas may be more malignant than supratentorial oligodendrogliomas

  15. Ultrasonographic and CT findings of hepatosplenic tuberculosis

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    Moon, Un Hyeon; Lee, Jeong Seok; Ko, Kang Seok; Park, Byung Ran; Yang, Dong Cheol; Im, Ju Hyeon [Kwangju Christian Hospital, Kwangju (Korea, Republic of); Kang, In Young [Kwangju Green Cross Hospital, Kwangju (Korea, Republic of)

    1998-08-01

    To evaluate the ultrasonographic and CT findings of hepatosplenic tuberculosis Materials and Methods: We retrospectively reviewed the ultrasonographic and CT findings of confirmed hepatosplenic tuberculosis in 12 patients. Six were men and six were women ; their average age was 41, and most were in their twenties. Lesions of the liver and spleen, as well as associated findings such as abdominal tuberculosis and other organ involvement of tuberculosis were analyzed. Results : There were three cases of hepatic tuberculosis, seven of splenic tuberculosis, and two of hepatosplenic involvement of tuberculosis. On the basis of the ultrasonographic and CT findings, hepatosplenic tuberculosis was classified as one of two patterns : miliary or micronodular, ormacronodular. The micronodular type was more common (9/12 cases) being characterized by innumerable micronodules,and with easy coalescence in the liver and spleen in five of the nine cases. The macronodular type of low density mass was noted in the other three patients. Splenomegaly was noted in 12 cases and hepatomegaly in ten. Pulmonary tuberculosis-including the miliary type(n=5)-was noted in eight patients. Associated abdominal tuberculosis such as lymphadenopathy with central low density and peripheral rim enhancement (n=6), tuberculous peritonitis(n=3),highly attenuated ascites(n=6), adrenal tuberculosis(n=1), renal tuberculosis(n=1), ovarian abscess(n=1), psoasabscess(n=1), and systemic tuberculosis such as central nervous system tuberculoma(n=2), cervical lymphadenopathy(n=4) and tuberculous spondylitis(n=1) were noted. Conclusion : Ultrasonography and CT were valuable in the detection and diagnosis of hepatosplenic tuberculosis.

  16. Gene finding in the chicken genome

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    Antonarakis Stylianos E

    2005-05-01

    Full Text Available Abstract Background Despite the continuous production of genome sequence for a number of organisms, reliable, comprehensive, and cost effective gene prediction remains problematic. This is particularly true for genomes for which there is not a large collection of known gene sequences, such as the recently published chicken genome. We used the chicken sequence to test comparative and homology-based gene-finding methods followed by experimental validation as an effective genome annotation method. Results We performed experimental evaluation by RT-PCR of three different computational gene finders, Ensembl, SGP2 and TWINSCAN, applied to the chicken genome. A Venn diagram was computed and each component of it was evaluated. The results showed that de novo comparative methods can identify up to about 700 chicken genes with no previous evidence of expression, and can correctly extend about 40% of homology-based predictions at the 5' end. Conclusions De novo comparative gene prediction followed by experimental verification is effective at enhancing the annotation of the newly sequenced genomes provided by standard homology-based methods.

  17. Milnacipran: recent findings in depression

    Directory of Open Access Journals (Sweden)

    Guest editors: Stuart Montgomery (London

    2010-08-01

    Full Text Available EDITORIAL FOREWORDPage 1   Milnacipran: recent findings in depression Stuart Montgomery (London, UK and Mike Briley (Castres, France REVIEWSPage 3   Suicidality: risk factors and the effects of antidepressants. The example of parallel reduction of suicidality and other depressive symptoms during treatment with the SNRI, milnacipran Philippe Courtet (Montpellier, FrancePage 9   Treatment of patients with comorbid depression and diabetes with metformin and milnacipran Peter Hofmann (Graz, AustriaPage 17  Antidepressant therapy with milnacipran and venlafaxine Lucilla Mansuy (Toulouse, FrancePage 23  Milnacipran: a unique antidepressant? Siegfried Kasper and Gerald Pail (Vienna, Austria This supplement is based on a symposium that took place at the 9th International Forum on Mood and Anxiety in Monte Carlo in November 2009 and is supported by an unconditional education grant from Pierre Fabre Médicament.

  18. A Unified Method of Finding Laplace Transforms, Fourier Transforms, and Fourier Series. [and] An Inversion Method for Laplace Transforms, Fourier Transforms, and Fourier Series. Integral Transforms and Series Expansions. Modules and Monographs in Undergraduate Mathematics and Its Applications Project. UMAP Units 324 and 325.

    Science.gov (United States)

    Grimm, C. A.

    This document contains two units that examine integral transforms and series expansions. In the first module, the user is expected to learn how to use the unified method presented to obtain Laplace transforms, Fourier transforms, complex Fourier series, real Fourier series, and half-range sine series for given piecewise continuous functions. In…

  19. CT findings in epileptic children

    International Nuclear Information System (INIS)

    CT findings in 43 children with generalized seizures (grand mal seizures) (GM group) and in 50 children with partial seizures (P group), classified according to clinical seizure type, were studied. 1) CT abnormalities were demonstrated in 19% (8/43) in GM group and in 40% (20/50) in P group, including localized CT abnormalities in 9.3% (4/43) and in 34% (17/50) respectively. CT abnormalities were found more frequently in cases with abnormal past histories and/or mental defects (MD) than in those without them. 2) In P group, localized CT abnormalities and generalized brain atrophy were observed in 13 and 7 cases respectively. In 40 cases with focal epileptic discharges (FED) in EEG, localized CT abnormalities were demonstrated in 23% (9/40). The sites of localized CT abnormalities corresponded in 73% (11/15) to the sites of focal suppression in EEG (i.e., slowing, low amplitude and lazy pattern) regardless of FED. 3) The bicaudate cerebro-ventricular index (B-CVI) in 19 cases in the normal control group over 2 years of age was 10.0 +- 1.2 (mean +- SD). Ventricular narrowing (VN), with B-CVI less than 8.2 (mean - 1.5 SD), was observed in 5, 17 and 27% in control, GM and P groups respectively, indicating more frequently in epileptic children than in normal controls. Seizures were well controlled in 85% (11/13) in VN group and in 70% (26/36) in normal ventricular group. Brain atrophy in CT findings to inspection was ascertained in all cases by measuring B-CVI. (author)

  20. Specific CT findings of eclampsia

    International Nuclear Information System (INIS)

    Two cases of specific computed tomographic (CT) findings of eclampsia were reported. Case 1 was a 25-year-old primipara in the 10th month of pregnancy, and Case 2 was a 36-year-old primipara in the 9th month of pregnancy. Both were brought to our hospital because of attacks of preeclampsia and eclampsia. On admission, they were in a comatose state. Computed tomography (CT) on admission showed low- and high-density areas in the basal ganglia regions in Case 1 and low-density areas in the same regions in Case 2. In Case 1, cerebral angiograms obtained two days after the attack showed diffuse cerebral vasospasms in the anterior and middle cerebral arteries of both sides and the basilar artery. In Case 2, however, cerebral angiograms obtained three days after the attack showed no abnormal findings. The patients were saved by crisis-overcoming emergency treatment and care. The neurological condition gradually improved. Repeated CT three weeks after the onset showed only a slight low-density area and a small high-density area in the left basal ganglia region in Case 1, while the low-density areas in the bilateral basal ganglia regions disappeared in Case 2. Seven weeks after the attack, cerebral angiography was again performed, but the diffuse vasospasms had disappeared. The clinical courses were good, and the patients were discharged about eight weeks after the onset, by which time their consciousness had become clear and the neurological deficits had been well overcome. Cerebrovascular disorders caused by toxemia of pregnancy is rare; when they do occur, the main lesions of the brain are edema, focal ischemia, thrombosis, and hemorrhage. They may be related to cerebral vasospasm, and subsequent ischemic changes are observed at times with eclampsia. (author)

  1. Accuracy of MRI findings in chronic lateral ankle ligament injury: Comparison with surgical findings

    International Nuclear Information System (INIS)

    Aim: To evaluate the accuracy of magnetic resonance imaging (MRI) findings in chronic lateral ankle ligament injury in comparison with that of surgical findings. Materials and methods: Forty-eight cases (25 men, 23 women, mean age 36 years) of clinically suspected chronic ankle ligament injury underwent MRI studies and surgery. Sagittal, coronal, and axial, T1-weighted, spin-echo, proton density and T2-weighted, fast spin-echo images with fat saturation were obtained in all patients. MRI examinations were read in consensus by two fellowship-trained academic musculoskeletal radiologists who evaluated the lateral ankle ligaments, including the anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) without clinical information. The results of the MRI studies were then compared with the surgical findings. Results: The MRI findings of ATFL injury showed a sensitivity of detection of complete tears of 75% and specificity of 86%. The sensitivity of detection of partial tears was 75% and the specificity was 78%. The sensitivity of detection of sprains was 44% and the specificity was 88%. Regarding the MRI findings of CFL injury, the sensitivity of detection of complete tears was 50% and the specificity was 98%. The sensitivity of detection of partial tear was 83% and the specificity was 93%. The sensitivity of detection of sprains was 100% and the specificity was 90%. Regarding the ATFL, the accuracies of detection were 88, 58, 77, and 85% for no injury, sprain, partial tear, and complete tear, respectively, and for the CFL the accuracies of detection were 90, 90, 92, and 96% for no injury, sprain, partial tear, and complete tear, respectively. Conclusions: The diagnosis of a complete tear of the ATFL on MRI is more sensitive than the diagnosis of a complete tear of the CFL. MRI findings of CFL injury are diagnostically specific but are not sensitive. However, only normal findings and complete tears were statistically significant between ATFL and CFL (p < 0.001).

  2. Finding communities in sparse networks

    CERN Document Server

    Singh, Abhinav

    2015-01-01

    Spectral algorithms based on matrix representations of networks are often used to detect communities but classic spectral methods based on the adjacency matrix and its variants fail to detect communities in sparse networks. New spectral methods based on non-backtracking random walks have recently been introduced that successfully detect communities in many sparse networks. However, the spectrum of non-backtracking random walks ignores hanging trees in networks that can contain information about the community structure of networks. We introduce the reluctant backtracking operators that explicitly account for hanging trees as they admit a small probability of returning to the immediately previous node unlike the non-backtracking operators that forbid an immediate return. We show that the reluctant backtracking operators can detect communities in certain sparse networks where the non-backtracking operators cannot while performing comparably on benchmark stochastic block model networks and real world networks. We...

  3. Losing a child: finding meaning in bereavement

    Directory of Open Access Journals (Sweden)

    Julia Bogensperger

    2014-03-01

    Full Text Available Background: Confronting the loss of a loved one leads us to the core questions of human existence. Bereaved parents have to deal with the rupture of a widely shared concept of what is perceived to be the natural course of life and are forced into meaning reconstruction. Objective: This study aims to expand upon existing work concerning specific themes of meaning reconstruction in a sample of bereaved parents. More specifically, the relationship between meaning reconstruction, complicated grief, and posttraumatic growth was analyzed, with special attention focused on traumatic and unexpected losses. Method: In a mixed methods approach, themes of meaning reconstruction (sense-making and benefit-finding were assessed in in-depth interviews with a total of 30 bereaved parents. Posttraumatic growth and complicated grief were assessed using standardized questionnaires, and qualitative and quantitative results were then merged using data transformation methods. Results: In total 42 themes of meaning reconstruction were abstracted from oral material. It was shown that sense-making themes ranged from causal explanations to complex philosophical beliefs about life and death. Benefit-finding themes contained thoughts about personal improvement as well as descriptions about social actions. Significant correlations were found between the extent of sense-making and posttraumatic growth scores (rs=0.54, rs=0.49; p<0.01, especially when the death was traumatic or unexpected (rs=0.67, rs=0.63; p<0.01. However, analysis revealed no significant correlation with complicated grief. Overall results corroborate meaning reconstruction themes and the importance of meaning reconstruction for posttraumatic growth.

  4. MR findings of trigeminal neurinoma

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hong Suk; Han, Moon Hee; Chang, Kee Hyun; Yoo, In Kyu; Kim, Sam Soo; Lee, Kyoung Won; Jung, Hee Won; Yeon, Kyung Mo [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    1997-08-01

    To describe the MRI findings of trigeminal neurinoma. We retrospectively analyzed the MRI findings of 19 patients with trigeminal neurinomas proven by surgery and pathologic examination. Axial T1- and T2-weighted MR images in all patients and gadolinium-enhanced T1-weighted images in 14 patients were obtained at 2.0T(8 cases), 1.5T(6 cases) or 0.5T(5 cases). These were analyzed in terms of tumor size, signal intensity, degree of contrast enhancement, the presence or absence of cystic change and denervation atrophy of the masticator muscles. Clinical manifestations included sensory abnormality or pain(n=12), headache(n=10), impaired visual acuity or diplopia(n=6), hearing loss or tinnitus(n=3), weakness of masticator muscles(n=2), and mass or nasal obstruction(n=2). On MR images, tumor size was seen to average 4.2(range 1.5-6)cm;tumors were located in the posterior cranial fossa(n=8), middle cranial fossa(n=4), ophthalmic nerve(n=2), maxillary nerve(n=1), and mandibular nerve(n=1), and in three cases were dumbbell-shaped and extended into both the middle and posterior cranial fossa. On T1-weighted images, signals were isointense with cortical grey matter, in ten cases(53%), and of low intensity in nine (47%);on T2-weighted images, signals were of high intensity in 15cases(79%) and were isointense in four (21%). Cystic change was seen in 12 cases(63%). After enhancement, all (14/14) the tumors enhanced. Denervation atrophy was seen in nine cases(47%) and all of these involved the trigeminal ganglion or mandibular nerve. A trigeminal neurinoma shows similar signal intensity and enhancement to other cranial neurinomas with a higher incidence of cystic degeneration. Its location and shape are characteristic, and where there is involvement of the trigeminal ganglion or mandibular nerve, denervation atrophy may be seen.

  5. MR findings of trigeminal neurinoma

    International Nuclear Information System (INIS)

    To describe the MRI findings of trigeminal neurinoma. We retrospectively analyzed the MRI findings of 19 patients with trigeminal neurinomas proven by surgery and pathologic examination. Axial T1- and T2-weighted MR images in all patients and gadolinium-enhanced T1-weighted images in 14 patients were obtained at 2.0T(8 cases), 1.5T(6 cases) or 0.5T(5 cases). These were analyzed in terms of tumor size, signal intensity, degree of contrast enhancement, the presence or absence of cystic change and denervation atrophy of the masticator muscles. Clinical manifestations included sensory abnormality or pain(n=12), headache(n=10), impaired visual acuity or diplopia(n=6), hearing loss or tinnitus(n=3), weakness of masticator muscles(n=2), and mass or nasal obstruction(n=2). On MR images, tumor size was seen to average 4.2(range 1.5-6)cm;tumors were located in the posterior cranial fossa(n=8), middle cranial fossa(n=4), ophthalmic nerve(n=2), maxillary nerve(n=1), and mandibular nerve(n=1), and in three cases were dumbbell-shaped and extended into both the middle and posterior cranial fossa. On T1-weighted images, signals were isointense with cortical grey matter, in ten cases(53%), and of low intensity in nine (47%);on T2-weighted images, signals were of high intensity in 15cases(79%) and were isointense in four (21%). Cystic change was seen in 12 cases(63%). After enhancement, all (14/14) the tumors enhanced. Denervation atrophy was seen in nine cases(47%) and all of these involved the trigeminal ganglion or mandibular nerve. A trigeminal neurinoma shows similar signal intensity and enhancement to other cranial neurinomas with a higher incidence of cystic degeneration. Its location and shape are characteristic, and where there is involvement of the trigeminal ganglion or mandibular nerve, denervation atrophy may be seen

  6. Computing methods

    CERN Document Server

    Berezin, I S

    1965-01-01

    Computing Methods, Volume 2 is a five-chapter text that presents the numerical methods of solving sets of several mathematical equations. This volume includes computation sets of linear algebraic equations, high degree equations and transcendental equations, numerical methods of finding eigenvalues, and approximate methods of solving ordinary differential equations, partial differential equations and integral equations.The book is intended as a text-book for students in mechanical mathematical and physics-mathematical faculties specializing in computer mathematics and persons interested in the

  7. Radiological findings in Wolfram syndrome

    International Nuclear Information System (INIS)

    To determine the precise radiologic findings in Wolfram syndrome (WFS) patients using objective techniques in order to better define the reference population for the clinicl evaluation. 16 patients (6 males, 10 female) with WFS found in 4 families were included in this study.14 patients with WFS-2 came from 3 families while 2 patients with EFS-1 came from one family. All patients were studied at Jordan University Hospital, Amman,Jordan from January 2001 to January 2003 by definite radiologic techniques as part of a thorough clinical comprehesive assesment. These incclude intravenous urography, abdominal and pelvic ultrasonography, barium meal, upper gastrointestinal endoscopy and magnetic resonance imaging with and without contrasts to the brain and the pituitary glands.5 of the female ptients had a small uterus. Spina bifida was found in 7, hydronephrosis in 9 and hydroureter in 5 patiets. Peptic ulcer was detected in 10 out of 14 available patients and helicobacter pylori in 7 out of 16 patients. Atrophy was detected was detected in all brains, 9 brain stems, 12 cerebellums and 14 optic tracts of all patients. The size of pituitary glands was variable. The particular radiological assesment of the patients with WFS proved that, urinary tract dialtation was detected in WFS-1and WFS-2 patients though all WFS-2 patients.No significant radiologic difference was between patients with WFS-1 and WFS-2. (author)

  8. MRI in insulinomas; Preliminary findings

    Energy Technology Data Exchange (ETDEWEB)

    Liessi, Guido (Ospedale Civile, Castelfranco Veneto (Italy). Servizio di Radiologia); Pasquali, Claudio; Alfano D' Andrea, Alfonso; Pedrazzoli, Sergio (Padova Universita, I Cattedra di: Patologia Speciale Chirurgica (Italy). Istituto di Clinica Chirurgica); Scandellari, Cesare (Padova Universita, Cattedra di Medicina Interna V (Italy). Istituto di Semeiotica Medica)

    After establishing the diagnosis of an insulinoma, most surgeons prefer preoperative localization. Selective arteriography is usually considered the gold standard for this purpose. Recently, computed tomography (CT) and preoperative US have contended the role to angiography. MRI has been used in few cases of endocrine pancreatic tumors, and its role in this particular field has to be defined. Between November 1988-September 1990 7 adult patients who had undergone surgery were evaluated. Eight tumors were resected in 6 patients who were cured; in an 18-year-old woman surgical treatment was unsuccessful. Arterio-graphy, CT, preoperative US, MRI and intraoperative US detected 2, 6, 6, 5 and 6 tumors respectively. Two insulinomas (0.2 and 0.7 cm) were found at histologic examination in resected specimen. The ability of intra-operative US and careful surgical exploration to resolve more than 90 percent of cases makes the preoperative use of arteriography and CT questionable value. If further experience confirms these findings, US and MRI may suffice. (author). 13 refs.; 3 figs.; 1 tab.

  9. Imaging findings of retroperitoneal ganglioneuroma

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Min Woo; Kim, Seung Hyup; Kim, Sun Ho; Moon, Min Hoan; Park, Byung Kwan; Choi, Hyuck Jae; Kim, Se Hyung; Jung, Sung Il [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

    2003-10-01

    To characterize the typical radiologic appearance of ganglioneuromas of the adrenal gland and extra-adrenal retroperitoneum. The findings of diagnostic imaging studies (CT, n=5; ultrasound, n=1) involving six patients aged 19-58 years with pathologically proven ganglioneuroma were retrospectively analyzed by three radiologist in terms of the lesions, size, shape, margin, location, CT attenuation (unenhanced/contrast-enhanced), necrosis, calcification, relationship with adjacent vessels, and US echogenicity. The maximum diameter of the six tumors ranged from 10 to 14 (mean, 11.3) cm, and the margin was well-defined in all cases. The homogeneous or slightly heterogeneous attenuation demonstrated at unenhanced CT was less than that of muscle. Dense nodular calcification was present in one case. At contrast-enhanced CT, enhancement was poor (n=5), mild and septum-like, or delayed, heterogeneous and focal (n=3), or involved subtle foci (n=1). In no case was there evidence of necrosis or hemorrhage. Local invasion was absent, but adjacent vascular encasement (n=2) or displacement (n=2) occurred. Ultrasonic examination demonstrated low echogenicity and mild heterogeneity (n=1). A ganglioneuroma is an uncommon benign neural crest tumor which should be included in the differential diagnosis of a retroperitoneal mass which presents as a well-defined tumor, tend to encase or displace adjacent major blood vessels, and shows low attenuation at unenhanced CT and poor or septum-like focal enhancement at contrast-enhanced CT.

  10. Imaging findings of retroperitoneal ganglioneuroma

    International Nuclear Information System (INIS)

    To characterize the typical radiologic appearance of ganglioneuromas of the adrenal gland and extra-adrenal retroperitoneum. The findings of diagnostic imaging studies (CT, n=5; ultrasound, n=1) involving six patients aged 19-58 years with pathologically proven ganglioneuroma were retrospectively analyzed by three radiologist in terms of the lesions, size, shape, margin, location, CT attenuation (unenhanced/contrast-enhanced), necrosis, calcification, relationship with adjacent vessels, and US echogenicity. The maximum diameter of the six tumors ranged from 10 to 14 (mean, 11.3) cm, and the margin was well-defined in all cases. The homogeneous or slightly heterogeneous attenuation demonstrated at unenhanced CT was less than that of muscle. Dense nodular calcification was present in one case. At contrast-enhanced CT, enhancement was poor (n=5), mild and septum-like, or delayed, heterogeneous and focal (n=3), or involved subtle foci (n=1). In no case was there evidence of necrosis or hemorrhage. Local invasion was absent, but adjacent vascular encasement (n=2) or displacement (n=2) occurred. Ultrasonic examination demonstrated low echogenicity and mild heterogeneity (n=1). A ganglioneuroma is an uncommon benign neural crest tumor which should be included in the differential diagnosis of a retroperitoneal mass which presents as a well-defined tumor, tend to encase or displace adjacent major blood vessels, and shows low attenuation at unenhanced CT and poor or septum-like focal enhancement at contrast-enhanced CT

  11. Ocular findings in alopecia areata.

    Science.gov (United States)

    Ergin, Can; Acar, Mutlu; Kaya Ak??, Havva; Gönül, Müzeyyen; Gürdal, Canan

    2015-11-01

    Alopecia areata is a T cell mediated disease with which many disorders may be associated. There are few studies reporting ocular findings in alopecia areata. The aim of the study is to assess tear function and ocular surface pathologies in alopecia areata. Thirty-two patients with alopecia areata and 20 age- and sex-matched healthy controls were enrolled in the study. Ocular surface disease index questionnaire, Schirmer, tear break-up time, and corneal staining stage tests were done. The data was analyzed using SPSS 10.0 software. One-way variance analysis and Chi-square tests were used as tests of significance. The patient group had significantly higher ocular surface disease index questionnaire and corneal staining stage test scores and lower tear break-up time test scores compared with the control group (P < 0.05). Dry eye disease (DED) was diagnosed in 27 (84%) of 32 alopecia areata patients and in only 3 (15%) of 20 controls, and there was a significant difference between the groups (P < 0.01). T cell mediated autoimmunity has a prominent role in the etiopathogenesis of alopecia areata and dry eye disease. We think that inflammatory mechanisms causing alopecia areata may trigger dry eye disease or vice versa. All patients with AA should be referred to an ophthalmologist for the evaluation of DED and other possible eye pathologies. PMID:26147700

  12. MR findings in pontocerebellar hypoplasia

    International Nuclear Information System (INIS)

    We present four cases with combined hypoplasia of the cerebellum and the ventral pons - pontocerebellar hypoplasia (PCH). PCH represents an autosomal recessive neurodegenerative disorder with fetal onset. The disease is rare, with less than 20 cases having been reported. The main findings of PCH and the inclusion criteria for our cases can be summarised as progressive microcephaly from birth, pontocerebellar hypoplasia documented by MRI and marked chorea, which may change, later in childhood, to more dystonic patterns. The cerebral cortex becomes progressively atrophic. Motor and mental development are delayed, and epilepsy, mainly tonic-clonic seizures, is frequent. The MRI features in all of our cases were: (1) Hypoplastic cerebellum situated close to the tentorium. The hypoplastic cerebellum has a reduced number of folia, in contrast to the normal number of thin folia in simple cerebellar atrophy. (2) The cerebellar hemispheres are reduced to bean-like or wing-like structures. The cerebellar hemispheres appear to 'float' in the posterior fossa. (3) Markedly hypoplastic ventral pons. (4) Slight atrophy of the supratentorial gyral pattern. (5) Dilated cerebromedullary cistern and fourth ventricle. (6) Delayed myelination of the white matter. (7) No significant disorganisation of brain architecture and no severe corpus callosum defect. (orig.)

  13. Finding the Density of Objects without Measuring Mass and Volume

    Science.gov (United States)

    Mumba, Frackson; Tsige, Mesfin

    2007-01-01

    A simple method based on the moment of forces and Archimedes' principle is described for finding density without measuring the mass and volume of an object. The method involves balancing two unknown objects of masses M[subscript 1] and M[subscript 2] on each side of a pivot on a metre rule and measuring their corresponding moment arms. The object…

  14. Regional Transmission Projects: Finding Solutions

    Energy Technology Data Exchange (ETDEWEB)

    The Keystone Center

    2005-06-15

    The Keystone Center convened and facilitated a year-long Dialogue on "Regional Transmission Projects: Finding Solutions" to develop recommendations that will help address the difficult and contentious issues related to expansions of regional electric transmission systems that are needed for reliable and economic transmission of power within and across regions. This effort brought together a cross-section of affected stakeholders and thought leaders to address the problem with the collective wisdom of their experience and interests. Transmission owners sat at the table with consumer advocates and environmental organizations. Representatives from regional transmission organizations exchanged ideas with state and federal regulators. Generation developers explored common interests with public power suppliers. Together, the Dialogue participants developed consensus solutions about how to begin unraveling some of the more intractable issues surrounding identification of need, allocation of costs, and reaching consensus on siting issues that can frustrate the development of regional transmission infrastructure. The recommendations fall into three broad categories: 1. Recommendations on appropriate institutional arrangements and processes for achieving regional consensus on the need for new or expanded transmission infrastructure 2. Recommendations on the process for siting of transmission lines 3. Recommendations on the tools needed to support regional planning, cost allocation, and siting efforts. List of Dialogue participants: List of Dialogue Participants: American Electric Power American Transmission Company American Wind Energy Association California ISO Calpine Corporation Cinergy Edison Electric Institute Environmental Defense Federal Energy Regulatory Commission Great River Energy International Transmission Company ISO-New England Iowa Public Utility Board Kanner & Associates Midwest ISO National Association of Regulatory Utility Commissioners National Association of State Utility Consumer Advocates National Grid Northeast Utilities PA Office of Consumer Advocates Pacific Gas & Electric Corporation Pennsylvania Public Utility Commission PJM Interconnection The Electricity Consumers Resource Council U.S. Department of Energy US Department of the Interior Van Ness Feldman Western Interstate Energy Board Wind on the Wires Wisconsin Public Service Commission Xcel Energy

  15. Effect of Encoding Method on the Distribution of Cardiac Arrhythmias

    CERN Document Server

    Mora, Luis A

    2011-01-01

    This paper presents the evaluation of the effect of the method of ECG signal encoding, based on nonlinear characteristics such as information entropy and Lempel-Ziv complexity, on the distribution of cardiac arrhythmias. Initially proposed a procedure electrocardiographic gating to compensate for errors inherent in the process of filtering segments. For the evaluation of distributions and determine which of the different encoding methods produces greater separation between different kinds of arrhythmias studied (AFIB, AFL, SVTA, VT, Normal's), use a function based on the dispersion of the elements on the centroid of its class, the result being that the best encoding for the entire system is through the method of threshold value for a ternary code with E = 1 / 12.

  16. Correlation of Asymmetric Breast Density Findings in Mammograms with Cytologic Findings

    Directory of Open Access Journals (Sweden)

    "M. Sirus

    2005-08-01

    Full Text Available Introduction & objectives: Mammography has had a major impact on the early detection of breast cancer; its ability to locate early stage cancer provides the physicians and patients with several treatment op-tions. Many studies have assessed the predictive value of specific mamaographic findings; however, few studies have covered asymmetric breast tissue, which has been reported to occur in 3% of all mammograms. Asymmetric breast tissue is usually benign and ap-pears secondary to variations in normal breast tissue, postoperative changes, or hormone replacement ther-apy. However, it may also indicate a developing mass or an underlying cancer. Patients & Methods: In this study, of the 2360 pa-tients referred to Seyedoshohada hospital for mam-mography during 1997-1998, 112 had asymmetric breast density in their mammographic reports from which 76 were selected. They later underwent FNA after clinical breast examination. Results: The incidence of asymmetric breast density finding in mamographies was reported to be 4.75% in this study. Half of the patients had clinical findings in their breast examination such as palpable breast mass. Normal cytologic findings were observed in 59.2% of the patients; 32.8% had non-proliferative lesions, 2.6% had hyperplasia without atypism, 1.3% had hy-perplasia with atypism, and in 1.3% carcinoma was detected. Discussion: Asymmetric breast tissue densities are frequently encountered at screening and diagnostic mammography. These findings are significant because they may indicate a neoplasm, especially if an associ-ated palpable mass is present. Once these lesions are detected at standard mammography, a thorough knowledge of the patient’s clinical history plus sup-plementary breast imaging with additional mammo-graphic views and ultrasound will allow more accu-rate interpretation of these potentially perplexing soft-tissue findings.

  17. CT findings in neonatal hypothermia

    Energy Technology Data Exchange (ETDEWEB)

    Schulman, H.; Laufer, L.; Berginer, J.; Hertzanu, Y. [Department of Radiology, Soroka Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, P. O. Box 151, Beer-Sheva 84101 (Israel); Hershkowitz, E.; Berenstein, T.; Sofer, S. [Pediatric Intensive Care Unit, Soroka Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva (Israel); Maor, E. [Department of Pathology, Soroka Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva (Israel)

    1998-06-01

    Background. Newborn infants are particularly prone to hypothermia, a condition with a high mortality. Objective. To study the CT brain patterns in infants with hypothermia and neurological symptoms. Materials and methods. We reviewed the brain CT of nine infants with neonatal hypothermia, multiple organ failure, seizures and coma. Results. Two infants had normal CT scans, acutely and at follow-up, and were clinically normal at follow-up. In seven infants, CT showed diffuse cerebral oedema, with reversal of the normal density relationship between grey and white matter and a relative increased density of the thalami, brainstem and cerebellum - the `reversal sign`. In six surviving infants with severe developmental delay, follow-up CT revealed cerebral atrophy with multicystic encephalomalacia. Conclusions. The `reversal sign` has been described in the abused child, birth asphyxia and anoxia due to drowning. Neonatal hypothermia is offered as a further cause. (orig.) With 6 figs., 1 tab., 13 refs.

  18. Cervical myelopathy: magnetic imaging findings

    International Nuclear Information System (INIS)

    69 patients with clinical signs of cervical myelopathy were examined using magnetic imaging (T1- and T2-suspended tomograms of the sagittal and transverse section using a device with 0.04 T field intensity). Vertebral disk hernias were revealed in 35 patients, compression of the spinal cord with metastases into vertebral body in 2, extramedullary tumor in 11, intramedullary tumor in 9, and syringomyelia in 12 patients. T2-suspended tomograms proved to be more informative due to their higher sensitivity to aqueous content. T1-suspended tomograms help assess the degree of spinal cord compression and the direction of the disk protrusion. Magnetic imaging is an informative method used for objective identification of the cases of myelopathy of cervical localization

  19. CT findings in neonatal hypothermia

    International Nuclear Information System (INIS)

    Background. Newborn infants are particularly prone to hypothermia, a condition with a high mortality. Objective. To study the CT brain patterns in infants with hypothermia and neurological symptoms. Materials and methods. We reviewed the brain CT of nine infants with neonatal hypothermia, multiple organ failure, seizures and coma. Results. Two infants had normal CT scans, acutely and at follow-up, and were clinically normal at follow-up. In seven infants, CT showed diffuse cerebral oedema, with reversal of the normal density relationship between grey and white matter and a relative increased density of the thalami, brainstem and cerebellum - the 'reversal sign'. In six surviving infants with severe developmental delay, follow-up CT revealed cerebral atrophy with multicystic encephalomalacia. Conclusions. The 'reversal sign' has been described in the abused child, birth asphyxia and anoxia due to drowning. Neonatal hypothermia is offered as a further cause. (orig.)

  20. Pulmonary high-resolution computed tomography findings in nephropathia epidemica

    Energy Technology Data Exchange (ETDEWEB)

    Paakkala, Antti, E-mail: antti.paakkala@pshp.fi [Medical Imaging Centre, Tampere University Hospital, 33521 Tampere (Finland); Jaervenpaeae, Ritva, E-mail: ritva.jarvenpaa@pshp.fi [Medical Imaging Centre, Tampere University Hospital, 33521 Tampere (Finland); Maekelae, Satu, E-mail: satu.marjo.makela@uta.fi [Department of Internal Medicine, Tampere University Hospital, 33521 Tampere (Finland); Medical School, University of Tampere, 33521 Tampere (Finland); Huhtala, Heini, E-mail: heini.huhtala@uta.fi [School of Public Health, University of Tampere, 33521 Tampere (Finland); Mustonen, Jukka, E-mail: jukka.mustonen@uta.fi [Department of Internal Medicine, Tampere University Hospital, 33521 Tampere (Finland); Medical School, University of Tampere, 33521 Tampere (Finland)

    2012-08-15

    Purpose: To evaluate lung high-resolution computed tomography (HRCT) findings in patients with Puumala hantavirus-induced nephropathia epidemica (NE), and to determine if these findings correspond to chest radiograph findings. Materials and methods: HRCT findings and clinical course were studied in 13 hospital-treated NE patients. Chest radiograph findings were studied in 12 of them. Results: Twelve patients (92%) showed lung parenchymal abnormalities in HRCT, while only 8 had changes in their chest radiography. Atelectasis, pleural effusion, intralobular and interlobular septal thickening were the most common HRCT findings. Ground-glass opacification (GGO) was seen in 4 and hilar and mediastinal lymphadenopathy in 3 patients. Atelectasis and pleural effusion were also mostly seen in chest radiographs, other findings only in HRCT. Conclusion: Almost every NE patient showed lung parenchymal abnormalities in HRCT. The most common findings of lung involvement in NE can be defined as accumulation of pleural fluid and atelectasis and intralobular and interlobular septal thickening, most profusely in the lower parts of the lung. As a novel finding, lymphadenopathy was seen in a minority, probably related to capillary leakage and overall fluid overload. Pleural effusion is not the prominent feature in other viral pneumonias, whereas intralobular and interlobular septal thickening are characteristic of other viral pulmonary infections as well. Lung parenchymal findings in HRCT can thus be taken not to be disease-specific in NE and HRCT is useful only for scientific purposes.