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Sample records for blind deblurring reconstruction

  1. Stochastic Blind Motion Deblurring

    KAUST Repository

    Xiao, Lei

    2015-05-13

    Blind motion deblurring from a single image is a highly under-constrained problem with many degenerate solutions. A good approximation of the intrinsic image can therefore only be obtained with the help of prior information in the form of (often non-convex) regularization terms for both the intrinsic image and the kernel. While the best choice of image priors is still a topic of ongoing investigation, this research is made more complicated by the fact that historically each new prior requires the development of a custom optimization method. In this paper, we develop a stochastic optimization method for blind deconvolution. Since this stochastic solver does not require the explicit computation of the gradient of the objective function and uses only efficient local evaluation of the objective, new priors can be implemented and tested very quickly. We demonstrate that this framework, in combination with different image priors produces results with PSNR values that match or exceed the results obtained by much more complex state-of-the-art blind motion deblurring algorithms.

  2. Deblurring

    Science.gov (United States)

    Gevins, A.; Le, J.; Leong, H.; McEvoy, L. K.; Smith, M. E.

    1999-01-01

    In most instances, traditional EEG methodology provides insufficient spatial detail to identify relationships between brain electrical events and structures and functions visualized by magnetic resonance imaging or positron emission tomography. This article describes a method called Deblurring for increasing the spatial detail of the EEG and for fusing neurophysiologic and neuroanatomic data. Deblurring estimates potentials near the outer convexity of the cortex using a realistic finite element model of the structure of a subject's head determined from their magnetic resonance images. Deblurring is not a source localization technique and thus makes no assumptions about the number or type of generator sources. The validity of Deblurring has been initially tested by comparing deblurred data with potentials measured with subdural grid recordings. Results suggest that deblurred topographic maps, registered with a subject's magnetic resonance imaging and rendered in three dimensions, provide better spatial detail than has heretofore been obtained with scalp EEG recordings. Example results are presented from research studies of somatosensory stimulation, movement, language, attention and working memory. Deblurred ictal EEG data are also presented, indicating that this technique may have future clinical application as an aid to seizure localization and surgical planning.

  3. An improved robust blind motion de-blurring algorithm for remote sensing images

    Science.gov (United States)

    He, Yulong; Liu, Jin; Liang, Yonghui

    2016-10-01

    Shift-invariant motion blur can be modeled as a convolution of the true latent image and the blur kernel with additive noise. Blind motion de-blurring estimates a sharp image from a motion blurred image without the knowledge of the blur kernel. This paper proposes an improved edge-specific motion de-blurring algorithm which proved to be fit for processing remote sensing images. We find that an inaccurate blur kernel is the main factor to the low-quality restored images. To improve image quality, we do the following contributions. For the robust kernel estimation, first, we adapt the multi-scale scheme to make sure that the edge map could be constructed accurately; second, an effective salient edge selection method based on RTV (Relative Total Variation) is used to extract salient structure from texture; third, an alternative iterative method is introduced to perform kernel optimization, in this step, we adopt l1 and l0 norm as the priors to remove noise and ensure the continuity of blur kernel. For the final latent image reconstruction, an improved adaptive deconvolution algorithm based on TV-l2 model is used to recover the latent image; we control the regularization weight adaptively in different region according to the image local characteristics in order to preserve tiny details and eliminate noise and ringing artifacts. Some synthetic remote sensing images are used to test the proposed algorithm, and results demonstrate that the proposed algorithm obtains accurate blur kernel and achieves better de-blurring results.

  4. Blind Image Deblurring Driven by Nonlinear Processing in the Edge Domain

    Directory of Open Access Journals (Sweden)

    Stefania Colonnese

    2004-12-01

    Full Text Available This work addresses the problem of blind image deblurring, that is, of recovering an original image observed through one or more unknown linear channels and corrupted by additive noise. We resort to an iterative algorithm, belonging to the class of Bussgang algorithms, based on alternating a linear and a nonlinear image estimation stage. In detail, we investigate the design of a novel nonlinear processing acting on the Radon transform of the image edges. This choice is motivated by the fact that the Radon transform of the image edges well describes the structural image features and the effect of blur, thus simplifying the nonlinearity design. The effect of the nonlinear processing is to thin the blurred image edges and to drive the overall blind restoration algorithm to a sharp, focused image. The performance of the algorithm is assessed by experimental results pertaining to restoration of blurred natural images.

  5. Effective Alternating Direction Optimization Methods for Sparsity-Constrained Blind Image Deblurring.

    Science.gov (United States)

    Xiong, Naixue; Liu, Ryan Wen; Liang, Maohan; Wu, Di; Liu, Zhao; Wu, Huisi

    2017-01-18

    Single-image blind deblurring for imaging sensors in the Internet of Things (IoT) is a challenging ill-conditioned inverse problem, which requires regularization techniques to stabilize the image restoration process. The purpose is to recover the underlying blur kernel and latent sharp image from only one blurred image. Under many degraded imaging conditions, the blur kernel could be considered not only spatially sparse, but also piecewise smooth with the support of a continuous curve. By taking advantage of the hybrid sparse properties of the blur kernel, a hybrid regularization method is proposed in this paper to robustly and accurately estimate the blur kernel. The effectiveness of the proposed blur kernel estimation method is enhanced by incorporating both the L 1 -norm of kernel intensity and the squared L 2 -norm of the intensity derivative. Once the accurate estimation of the blur kernel is obtained, the original blind deblurring can be simplified to the direct deconvolution of blurred images. To guarantee robust non-blind deconvolution, a variational image restoration model is presented based on the L 1 -norm data-fidelity term and the total generalized variation (TGV) regularizer of second-order. All non-smooth optimization problems related to blur kernel estimation and non-blind deconvolution are effectively handled by using the alternating direction method of multipliers (ADMM)-based numerical methods. Comprehensive experiments on both synthetic and realistic datasets have been implemented to compare the proposed method with several state-of-the-art methods. The experimental comparisons have illustrated the satisfactory imaging performance of the proposed method in terms of quantitative and qualitative evaluations.

  6. Effective Alternating Direction Optimization Methods for Sparsity-Constrained Blind Image Deblurring

    Directory of Open Access Journals (Sweden)

    Naixue Xiong

    2017-01-01

    Full Text Available Single-image blind deblurring for imaging sensors in the Internet of Things (IoT is a challenging ill-conditioned inverse problem, which requires regularization techniques to stabilize the image restoration process. The purpose is to recover the underlying blur kernel and latent sharp image from only one blurred image. Under many degraded imaging conditions, the blur kernel could be considered not only spatially sparse, but also piecewise smooth with the support of a continuous curve. By taking advantage of the hybrid sparse properties of the blur kernel, a hybrid regularization method is proposed in this paper to robustly and accurately estimate the blur kernel. The effectiveness of the proposed blur kernel estimation method is enhanced by incorporating both the L 1 -norm of kernel intensity and the squared L 2 -norm of the intensity derivative. Once the accurate estimation of the blur kernel is obtained, the original blind deblurring can be simplified to the direct deconvolution of blurred images. To guarantee robust non-blind deconvolution, a variational image restoration model is presented based on the L 1 -norm data-fidelity term and the total generalized variation (TGV regularizer of second-order. All non-smooth optimization problems related to blur kernel estimation and non-blind deconvolution are effectively handled by using the alternating direction method of multipliers (ADMM-based numerical methods. Comprehensive experiments on both synthetic and realistic datasets have been implemented to compare the proposed method with several state-of-the-art methods. The experimental comparisons have illustrated the satisfactory imaging performance of the proposed method in terms of quantitative and qualitative evaluations.

  7. Effective Alternating Direction Optimization Methods for Sparsity-Constrained Blind Image Deblurring

    Science.gov (United States)

    Xiong, Naixue; Liu, Ryan Wen; Liang, Maohan; Wu, Di; Liu, Zhao; Wu, Huisi

    2017-01-01

    Single-image blind deblurring for imaging sensors in the Internet of Things (IoT) is a challenging ill-conditioned inverse problem, which requires regularization techniques to stabilize the image restoration process. The purpose is to recover the underlying blur kernel and latent sharp image from only one blurred image. Under many degraded imaging conditions, the blur kernel could be considered not only spatially sparse, but also piecewise smooth with the support of a continuous curve. By taking advantage of the hybrid sparse properties of the blur kernel, a hybrid regularization method is proposed in this paper to robustly and accurately estimate the blur kernel. The effectiveness of the proposed blur kernel estimation method is enhanced by incorporating both the L1-norm of kernel intensity and the squared L2-norm of the intensity derivative. Once the accurate estimation of the blur kernel is obtained, the original blind deblurring can be simplified to the direct deconvolution of blurred images. To guarantee robust non-blind deconvolution, a variational image restoration model is presented based on the L1-norm data-fidelity term and the total generalized variation (TGV) regularizer of second-order. All non-smooth optimization problems related to blur kernel estimation and non-blind deconvolution are effectively handled by using the alternating direction method of multipliers (ADMM)-based numerical methods. Comprehensive experiments on both synthetic and realistic datasets have been implemented to compare the proposed method with several state-of-the-art methods. The experimental comparisons have illustrated the satisfactory imaging performance of the proposed method in terms of quantitative and qualitative evaluations. PMID:28106764

  8. Iterative Blind Deconvolution Algorithm for Deblurring PSP Image of Rotating Surfaces

    Science.gov (United States)

    Pandey, Anshuman; Gregory, James

    2015-11-01

    Fast Pressure-Sensitive Paint (PSP) is used in this work to measure unsteady surface pressures on rotating bodies, with iterative image deblurring schemes being developed to correct for image blur at high rotation rates. A significant amount of rotational blur can occur in PSP images acquired in the lifetime mode when the time scale of luminescent decay is long relative to the rotational speed. Image deblurring schemes have been developed to address this problem, but are not currently able to handle strong pressure gradients. Since the local point spread function at each point on the rotor depends on the unknown pressure, restoring such an image is a spatially-varying blind deconvolution problem. An iterative scheme based on the lifetime decay characteristics of PSP has been developed for restoring this image. The scheme estimates the spatially-varying blur kernel without filtering the blurred image and then restores it using classical iterative regularization tools. The resulting scheme is evaluated using computationally-generated pressure fields with strong gradients, as well as experimental data with strong gradients in luminescent lifetime due to a nitrogen jet. Factors such as convergence, image noise, and regularization-iteration count are studied in this work. Funded by the U.S. Government under Agreement No. W911W6-11-2-0010 through the Georgia Tech Vertical Lift Research Center of Excellence.

  9. Simultaneous deblurring and iterative reconstruction of CBCT for image guided brain radiosurgery

    Science.gov (United States)

    Hashemi, SayedMasoud; Song, William Y.; Sahgal, Arjun; Lee, Young; Huynh, Christopher; Grouza, Vladimir; Nordström, Håkan; Eriksson, Markus; Dorenlot, Antoine; Régis, Jean Marie; Mainprize, James G.; Ruschin, Mark

    2017-04-01

    One of the limiting factors in cone-beam CT (CBCT) image quality is system blur, caused by detector response, x-ray source focal spot size, azimuthal blurring, and reconstruction algorithm. In this work, we develop a novel iterative reconstruction algorithm that improves spatial resolution by explicitly accounting for image unsharpness caused by different factors in the reconstruction formulation. While the model-based iterative reconstruction techniques use prior information about the detector response and x-ray source, our proposed technique uses a simple measurable blurring model. In our reconstruction algorithm, denoted as simultaneous deblurring and iterative reconstruction (SDIR), the blur kernel can be estimated using the modulation transfer function (MTF) slice of the CatPhan phantom or any other MTF phantom, such as wire phantoms. The proposed image reconstruction formulation includes two regularization terms: (1) total variation (TV) and (2) nonlocal regularization, solved with a split Bregman augmented Lagrangian iterative method. The SDIR formulation preserves edges, eases the parameter adjustments to achieve both high spatial resolution and low noise variances, and reduces the staircase effect caused by regular TV-penalized iterative algorithms. The proposed algorithm is optimized for a point-of-care head CBCT unit for image-guided radiosurgery and is tested with CatPhan phantom, an anthropomorphic head phantom, and 6 clinical brain stereotactic radiosurgery cases. Our experiments indicate that SDIR outperforms the conventional filtered back projection and TV penalized simultaneous algebraic reconstruction technique methods (represented by adaptive steepest-descent POCS algorithm, ASD-POCS) in terms of MTF and line pair resolution, and retains the favorable properties of the standard TV-based iterative reconstruction algorithms in improving the contrast and reducing the reconstruction artifacts. It improves the visibility of the high contrast details

  10. Deblured Gaussian Blurred Images

    CERN Document Server

    Al-amri, Salem Saleh; D, Khamitkar S

    2010-01-01

    This paper attempts to undertake the study of Restored Gaussian Blurred Images. by using four types of techniques of deblurring image as Wiener filter, Regularized filter, Lucy Richardson deconvlutin algorithm and Blind deconvlution algorithm with an information of the Point Spread Function (PSF) corrupted blurred image with Different values of Size and Alfa and then corrupted by Gaussian noise. The same is applied to the remote sensing image and they are compared with one another, So as to choose the base technique for restored or deblurring image.This paper also attempts to undertake the study of restored Gaussian blurred image with no any information about the Point Spread Function (PSF) by using same four techniques after execute the guess of the PSF, the number of iterations and the weight threshold of it. To choose the base guesses for restored or deblurring image of this techniques.

  11. Blind reconstruction of linear scrambler

    Institute of Scientific and Technical Information of China (English)

    Hui Xie; Fenghua Wang; Zhitao Huang

    2014-01-01

    An algorithm based on eigenanalysis technique and Walsh-Hadamard transform (WHT) is proposed. The algorithm contains two steps. Firstly, the received sequence is divided into temporal windows, and a covariance matrix is computed. The li-near feedback shift register (LFSR) sequence is reconstructed from the first eigenvector of this matrix. Secondly, equations ac-cording to the recovered LFSR sequence are constructed, and the Walsh spectrum corresponding to the equations is computed. The feedback polynomial of LFSR is estimated from the Walsh spec-trum. The validity of the algorithm is verified by the simulation result. Final y, case studies are presented to il ustrate the perfor-mance of the blind reconstruction method.

  12. Deblurring in iterative reconstruction of half CBCT for image guided brain radiosurgery

    Science.gov (United States)

    Hashemi, SayedMasoud; Lee, Young; Eriksson, Markus; Nordström, Hâkan; Song, Bongyong; Nam, Wooseok; Sahgal, Arjun; Song, William; Ruschin, Mark

    2016-03-01

    A high spatial resolution iterative reconstruction algorithm is proposed for a half cone beam CT (HCBCT) geometry. The proposed algorithm improves spatial resolution by explicitly accounting for image blurriness caused by different factors, such as extended X-ray source and detector response. The blurring kernel is estimated using the MTF slice of the Catphan phantom. The proposed algorithm is specifically optimized for the new Leksell Gamma Knife Icon (Elekta AB, Stockholm, Sweden) which incorporates the HCBCT geometry to accommodate the existing treatment couch while covering down to the base-of-skull in the reconstructed field-of-view. Image reconstruction involves a Fourier-based scaling simultaneous algebraic reconstruction technique (SART) coupled with total variation (TV) minimization and non-local mean denoising, solved using a split Bregman separation technique that splits the reconstruction problem into a gradient based updating step and a TV-based deconvolution algorithm. This formulation preserves edges and reduces the staircase effect caused by regular TV-penalized iterative algorithms. Our experiments indicate that our proposed method outperforms the conventional filtered back projection and TV penalized SART methods in terms of line pair resolution and retains the favorable properties of the standard TV-penalized reconstruction.

  13. Rolling Shutter Motion Deblurring

    KAUST Repository

    Su, Shuochen

    2015-06-07

    Although motion blur and rolling shutter deformations are closely coupled artifacts in images taken with CMOS image sensors, the two phenomena have so far mostly been treated separately, with deblurring algorithms being unable to handle rolling shutter wobble, and rolling shutter algorithms being incapable of dealing with motion blur. We propose an approach that delivers sharp and undis torted output given a single rolling shutter motion blurred image. The key to achieving this is a global modeling of the camera motion trajectory, which enables each scanline of the image to be deblurred with the corresponding motion segment. We show the results of the proposed framework through experiments on synthetic and real data.

  14. Blind fluorescence structured illumination microscopy: A new reconstruction strategy

    CERN Document Server

    Labouesse, S; Idier, J; Bourguignon, S; Liu, P; Sentenac, A

    2016-01-01

    In this communication, a fast reconstruction algorithm is proposed for fluorescence \\textit{blind} structured illumination microscopy (SIM) under the sample positivity constraint. This new algorithm is by far simpler and faster than existing solutions, paving the way to 3D and/or real-time 2D reconstruction.

  15. Low-Complexity Regularization Algorithms for Image Deblurring

    KAUST Repository

    Alanazi, Abdulrahman

    2016-11-01

    Image restoration problems deal with images in which information has been degraded by blur or noise. In practice, the blur is usually caused by atmospheric turbulence, motion, camera shake, and several other mechanical or physical processes. In this study, we present two regularization algorithms for the image deblurring problem. We first present a new method based on solving a regularized least-squares (RLS) problem. This method is proposed to find a near-optimal value of the regularization parameter in the RLS problems. Experimental results on the non-blind image deblurring problem are presented. In all experiments, comparisons are made with three benchmark methods. The results demonstrate that the proposed method clearly outperforms the other methods in terms of both the output PSNR and structural similarity, as well as the visual quality of the deblurred images. To reduce the complexity of the proposed algorithm, we propose a technique based on the bootstrap method to estimate the regularization parameter in low and high-resolution images. Numerical results show that the proposed technique can effectively reduce the computational complexity of the proposed algorithms. In addition, for some cases where the point spread function (PSF) is separable, we propose using a Kronecker product so as to reduce the computations. Furthermore, in the case where the image is smooth, it is always desirable to replace the regularization term in the RLS problems by a total variation term. Therefore, we propose a novel method for adaptively selecting the regularization parameter in a so-called square root regularized total variation (SRTV). Experimental results demonstrate that our proposed method outperforms the other benchmark methods when applied to smooth images in terms of PSNR, SSIM and the restored image quality. In this thesis, we focus on the non-blind image deblurring problem, where the blur kernel is assumed to be known. However, we developed algorithms that also work

  16. Multiframe Blind Super Resolution Imaging Based on Blind Deconvolution

    Institute of Scientific and Technical Information of China (English)

    元伟; 张立毅

    2016-01-01

    As an ill-posed problem, multiframe blind super resolution imaging recovers a high resolution image from a group of low resolution images with some degradations when the information of blur kernel is limited. Note that the quality of the recovered image is influenced more by the accuracy of blur estimation than an advanced regularization. We study the traditional model of the multiframe super resolution and modify it for blind deblurring. Based on the analysis, we proposed two algorithms. The first one is based on the total variation blind deconvolution algorithm and formulated as a functional for optimization with the regularization of blur. Based on the alternating minimization and the gradient descent algorithm, the high resolution image and the unknown blur kernel are esti-mated iteratively. By using the median shift and add operator, the second algorithm is more robust to the outlier influence. The MSAA initialization simplifies the interpolation process to reconstruct the blurred high resolution image for blind deblurring and improves the accuracy of blind super resolution imaging. The experimental results demonstrate the superiority and accuracy of our novel algorithms.

  17. Semi-blind Sparse Image Reconstruction with Application to MRFM

    CERN Document Server

    Park, Se Un; Hero, Alfred O

    2012-01-01

    We propose a solution to the image deconvolution problem where the convolution kernel or point spread function (PSF) is assumed to be only partially known. Small perturbations generated from the model are exploited to produce a few principal components explaining the PSF uncertainty in a high dimensional space. Unlike recent developments on blind deconvolution of natural images, we assume the image is sparse in the pixel basis, a natural sparsity arising in magnetic resonance force microscopy (MRFM). Our approach adopts a Bayesian Metropolis-within-Gibbs sampling framework. The performance of our Bayesian semi-blind algorithm for sparse images is superior to previously proposed semi-blind algorithms such as the alternating minimization (AM) algorithm and blind algorithms developed for natural images. We illustrate our myopic algorithm on real MRFM tobacco virus data.

  18. Sparse Poisson noisy image deblurring.

    Science.gov (United States)

    Carlavan, Mikael; Blanc-Féraud, Laure

    2012-04-01

    Deblurring noisy Poisson images has recently been a subject of an increasing amount of works in many areas such as astronomy and biological imaging. In this paper, we focus on confocal microscopy, which is a very popular technique for 3-D imaging of biological living specimens that gives images with a very good resolution (several hundreds of nanometers), although degraded by both blur and Poisson noise. Deconvolution methods have been proposed to reduce these degradations, and in this paper, we focus on techniques that promote the introduction of an explicit prior on the solution. One difficulty of these techniques is to set the value of the parameter, which weights the tradeoff between the data term and the regularizing term. Only few works have been devoted to the research of an automatic selection of this regularizing parameter when considering Poisson noise; therefore, it is often set manually such that it gives the best visual results. We present here two recent methods to estimate this regularizing parameter, and we first propose an improvement of these estimators, which takes advantage of confocal images. Following these estimators, we secondly propose to express the problem of the deconvolution of Poisson noisy images as the minimization of a new constrained problem. The proposed constrained formulation is well suited to this application domain since it is directly expressed using the antilog likelihood of the Poisson distribution and therefore does not require any approximation. We show how to solve the unconstrained and constrained problems using the recent alternating-direction technique, and we present results on synthetic and real data using well-known priors, such as total variation and wavelet transforms. Among these wavelet transforms, we specially focus on the dual-tree complex wavelet transform and on the dictionary composed of curvelets and an undecimated wavelet transform.

  19. Rotational image deblurring with sparse matrices

    DEFF Research Database (Denmark)

    Hansen, Per Christian; Nagy, James G.; Tigkos, Konstantinos

    2014-01-01

    We describe iterative deblurring algorithms that can handle blur caused by a rotation along an arbitrary axis (including the common case of pure rotation). Our algorithms use a sparse-matrix representation of the blurring operation, which allows us to easily handle several different boundary cond...

  20. Towards easy and reliable AFM tip shape determination using blind tip reconstruction.

    Science.gov (United States)

    Flater, Erin E; Zacharakis-Jutz, George E; Dumba, Braulio G; White, Isaac A; Clifford, Charles A

    2014-11-01

    Quantitative determination of the geometry of an atomic force microscope (AFM) probe tip is critical for robust measurements of the nanoscale properties of surfaces, including accurate measurement of sample features and quantification of tribological characteristics. Blind tip reconstruction, which determines tip shape from an AFM image scan without knowledge of tip or sample shape, was established most notably by Villarrubia [J. Res. Natl. Inst. Stand. Tech. 102 (1997)] and has been further developed since that time. Nevertheless, the implementation of blind tip reconstruction for the general user to produce reliable and consistent estimates of tip shape has been hindered due to ambiguity about how to choose the key input parameters, such as tip matrix size and threshold value, which strongly impact the results of the tip reconstruction. These key parameters are investigated here via Villarrubia's blind tip reconstruction algorithms in which we have added the capability for users to systematically vary the key tip reconstruction parameters, evaluate the set of possible tip reconstructions, and determine the optimal tip reconstruction for a given sample. We demonstrate the capabilities of these algorithms through analysis of a set of simulated AFM images and provide practical guidelines for users of the blind tip reconstruction method. We present a reliable method to choose the threshold parameter corresponding to an optimal reconstructed tip shape for a given image. Specifically, we show that the trend in how the reconstructed tip shape varies with threshold number is so regular that the optimal, or Goldilocks, threshold value corresponds with the peak in the derivative of the RMS difference with respect to the zero threshold curve vs. threshold number.

  1. The regularized blind tip reconstruction algorithm as a scanning probe microscopy tip metrology method

    CERN Document Server

    Jozwiak, G; Masalska, A; Gotszalk, T; Ritz, I; Steigmann, H

    2011-01-01

    The problem of an accurate tip radius and shape characterization is very important for determination of surface mechanical and chemical properties on the basis of the scanning probe microscopy measurements. We think that the most favorable methods for this purpose are blind tip reconstruction methods, since they do not need any calibrated characterizers and might be performed on an ordinary SPM setup. As in many other inverse problems also in case of these methods the stability of the solution in presence of vibrational and electronic noise needs application of so called regularization techniques. In this paper the novel regularization technique (Regularized Blind Tip Reconstruction - RBTR) for blind tip reconstruction algorithm is presented. It improves the quality of the solution in presence of isotropic and anisotropic noise. The superiority of our approach is proved on the basis of computer simulations and analysis of images of the Budget Sensors TipCheck calibration standard. In case of characterization ...

  2. A new deblurring morphological filter for hyperspectral images

    Science.gov (United States)

    Abdelkawy, Ezz Eldin F.; Mahmoud, Tarek A.; Hussein, Wesam M.

    2011-06-01

    Hyperspectral imaging becomes an important technique that increases the valuable information enclosed within the image. Spectral cube produced by this type of imaging introduces a new material signature known as "spectral signature". This signature is unique for each material as it depends on the molecular composition of the material surface. To produce the spectral cube, a spectrometer should be used in the imagery device to split the electromagnetic energy at different wavelengths before its projection on the imaging array. This spectrometer may be a dispersive element, such as prism and grating, or an electronically tuneable filter. Some of dispersive spectrometers, such as Fourier transform interferometer (FTIR) and image multi-spectral imaging (IMSS), are based on sliding the lenses, or mirrors, along the optical axis which may result in a slightly out-of-focus blurring. Blind deconvolution techniques have been successfully used to decrease this blurring but at the expense of edge sharpening which may be a problem in some applications such as target detection and recognition. In this paper, we introduce a new method to deblurr the hyperspectral images keeping edges as sharp as possible. This is done by firstly detecting the edges locations and then applying a class of morphological filtering. Motivated by the success of threshold decomposition, gradient-based operators are used to detect the locations of these edges followed by an adaptive morphological filter to sharpen these detected edges. Experimental results demonstrate that the performance of the proposed deblurring filter is superior to that of the blind deconvolution methods.

  3. Performance Comparison of Reconstruction Algorithms in Discrete Blind Multi-Coset Sampling

    DEFF Research Database (Denmark)

    Grigoryan, Ruben; Arildsen, Thomas; Tandur, Deepaknath

    2012-01-01

    This paper investigates the performance of different reconstruction algorithms in discrete blind multi-coset sampling. Multi-coset scheme is a promising compressed sensing architecture that can replace traditional Nyquist-rate sampling in the applications with multi-band frequency sparse signals....... The performance of the existing compressed sensing reconstruction algorithms have not been investigated yet for the discrete multi-coset sampling. We compare the following algorithms – orthogonal matching pursuit, multiple signal classification, subspace-augmented multiple signal classification, focal under...

  4. Bound Alternative Direction Optimization for Image Deblurring

    Directory of Open Access Journals (Sweden)

    Xiangrong Zeng

    2014-01-01

    the ℓp regularizer by a novel majorizer and then, based on a variable splitting, to reformulate the bound unconstrained problem into a constrained one, which is then addressed via an augmented Lagrangian method. The proposed algorithm actually combines the reweighted ℓ1 minimization method and the alternating direction method of multiples (ADMM such that it succeeds in extending the application of ADMM to ℓp minimization problems. The conducted experimental studies demonstrate the superiority of the proposed algorithm for the synthesis ℓp minimization over the state-of-the-art algorithms for the synthesis ℓ1 minimization on image deblurring.

  5. Image Deblurring Using Sparse-Land Model

    Directory of Open Access Journals (Sweden)

    Harini. B

    2012-06-01

    Full Text Available - In this paper, the problem of deblurring and poor image resolution is addressed and extended the task by removing blur and noise in the image to form a restored image as the output. Haar Wavelet transform based Wiener filtering is used in this algorithm. Soft Thresholding and Parallel Coordinate Descent (PCD iterative shrinkage algorithm are used for removal of noise and deblurring. Sequential Subspace Optimization (SESOP method or Line search method provides speed-up to this process. Sparse-land model is an emerging and powerful method to describe signals based on the sparsity and redundancy of their representations. Sparse coding is a key principle that underlies wavelet representation of images. Coefficient obtained after removal of noise and blur are not truly Sparse and so Minimum Mean Squared Error estimator (MMSE estimates the Sparse vectors. Sparse representation of signals have drawn considerable interest in recent years. Sparse coding is a key principle that underlies wavelet representation of images. In this paper, we explain the effort of seeking a common wavelet sparse coding of images from same object category leads to an active basis model called Sparse-land model, where the images share the same set of selected wavelet elements, which forms a linear basis for restoring the blurred image.

  6. Improvement of image performance in digital breast tomosynthesis (DBT) by incorporating a compressed-sensing (CS)-based deblurring scheme

    Science.gov (United States)

    Kim, Kyuseok; Park, Yeonok; Cho, Heemoon; Cho, Hyosung; Je, Uikyu; Park, Chulkyu; Lim, Hyunwoo; Park, Soyoung; Woo, Taeho; Choi, Sungil

    2016-10-01

    In this work, we investigated a compressed-sensing (CS)-based deblurring scheme incorporated with the total-variation (TV) regularization penalty for image deblurring of high accuracy and adopted it into the image reconstruction in conventional digital breast tomosynthesis (DBT). We implemented the proposed algorithm and performed a systematic simulation to demonstrate its viability for improving the image performance in DBT as well as two-dimensional (2D) mammography. In the simulation, blurred noisy projection images of a 3D numerical breast phantom were generated by convolving their original (or exact) version by a designed 2D Gaussian filter kernel (standard deviation=2 in pixel unit, kernel size=11×11), followed by adding Gaussian noise (mean=0, variance=0.05), and deblurred by using the algorithm before performing the DBT reconstruction procedure. Here the projection images were taken with a half tomographic angle of θ=20° and an angle step of Δθ=2°. We investigated the image performance of the reconstructed DBT images quantitatively in terms of the modulation and the slice-sensitive profile (SSP).

  7. Mobile image based color correction using deblurring

    Science.gov (United States)

    Wang, Yu; Xu, Chang; Boushey, Carol; Zhu, Fengqing; Delp, Edward J.

    2015-03-01

    Dietary intake, the process of determining what someone eats during the course of a day, provides valuable insights for mounting intervention programs for prevention of many chronic diseases such as obesity and cancer. The goals of the Technology Assisted Dietary Assessment (TADA) System, developed at Purdue University, is to automatically identify and quantify foods and beverages consumed by utilizing food images acquired with a mobile device. Color correction serves as a critical step to ensure accurate food identification and volume estimation. We make use of a specifically designed color checkerboard (i.e. a fiducial marker) to calibrate the imaging system so that the variations of food appearance under different lighting conditions can be determined. In this paper, we propose an image quality enhancement technique by combining image de-blurring and color correction. The contribution consists of introducing an automatic camera shake removal method using a saliency map and improving the polynomial color correction model using the LMS color space.

  8. An effective PN blind estimation reconstruction strategy to solve data reversions interference

    Institute of Scientific and Technical Information of China (English)

    Zhang Yi; Zhang Zhongzhao

    2007-01-01

    In a direct spectrum (DS) system, the PN code can be estimated by analyzing the singular vectors of the received data matrix in order to blind despread in a non-cooperative context. But as there are information data reversions in the analyzed data matrix, some parts of the estimated PN code may be invertible to the original PN code, which may bring about problems in the following despreading process. In order to solve this problem, a method to well reconstruct the PN code is proposed. This method is based on power detection. The combination scheme which has the maximum power is the best combination scheme that is most suitable to the original PN code. Simulation results show that the method can reconstruct the PN code very well, even if the signal-to-noise ratio is low.

  9. Noise reduction by sparse representation in learned dictionaries for application to blind tip reconstruction problem

    Science.gov (United States)

    Jóźwiak, Grzegorz

    2017-03-01

    Scanning probe microscopy (SPM) is a well known tool used for the investigation of phenomena in objects in the nanometer size range. However, quantitative results are limited by the size and the shape of the nanoprobe used in experiments. Blind tip reconstruction (BTR) is a very popular method used to reconstruct the upper boundary on the shape of the probe. This method is known to be very sensitive to all kinds of interference in the atomic force microscopy (AFM) image. Due to mathematical morphology calculus, the interference makes the BTR results biased rather than randomly disrupted. For this reason, the careful choice of methods used for image enhancement and denoising, as well as the shape of a calibration sample are very important. In the paper, the results of thorough investigations on the shape of a calibration standard are shown. A novel shape is proposed and a tool for the simulation of AFM images of this calibration standard was designed. It was shown that careful choice of the initial tip allows us to use images of hole structures to blindly reconstruct the shape of a probe. The simulator was used to test the impact of modern filtration algorithms on the BTR process. These techniques are based on sparse approximation with function dictionaries learned on the basis of an image itself. Various learning algorithms and parameters were tested to determine the optimal combination for sparse representation. It was observed that the strong reduction of noise does not guarantee strong reduction in reconstruction errors. It seems that further improvements will be possible by the combination of BTR and a noise reduction procedure.

  10. Blurring and Deblurring Digital Images Using the Dihedral Group

    Directory of Open Access Journals (Sweden)

    Husein Hadi Abbas Jassim

    2015-12-01

    Full Text Available A new method of blurring and deblurring digital images is presented. The approach is based on using new filters generating from average filter and H-filters using the action of the dihedral group. These filters are called HB-filters; used to cause a motion blur and then deblurring affected images. Also, enhancing images using HB-filters is presented as compared to other methods like Average, Gaussian, and Motion. Results and analysis show that the HB-filters are better in peak signal to noise ratio (PSNR and RMSE.

  11. Remote Sensing Image Deblurring Based on Grid Computation

    Institute of Scientific and Technical Information of China (English)

    LI Sheng-yang; ZHU Chong-guang; GE Ping-ju

    2006-01-01

    In general, there is a demand for real-time processing of mass quantity remote sensing images. However, the task is not only data-intensive but also computating-intensive. Distributed processing is a hot topic in remote sensing processing and image deblurring is also one of the most important needs. In order to satisfy the demand for quick processing and deblurring of mass quantity satellite images, we developed a distributed, grid computation-based platform as well as a corresponding middleware for grid computation. Both a constrained power spectrum equalization algorithm and effective block processing measures, which can avoid boundary effect, were applied during the processing. The result is satisfactory since computation efficiency and visual effect were greatly improved. It can be concluded that the technology of spatial information grids is effective for mass quantity remote sensing image processing.

  12. Uniform and Non-Uniform Single Image Deblurring Based on Sparse Representation and Adaptive Dictionary Learning

    Directory of Open Access Journals (Sweden)

    Ashwini M. Deshpande

    2014-02-01

    Full Text Available Considering the sparseness property of images, a sparse representation based iterative deblurring method is presented for single image deblurring under uniform and non-uniform motion blur. The approach taken is based on sparse and redundant representations over adaptively training dictionaries from single blurred-noisy image itself. Further, the K-SVD algorithm is used to obtain a dictionary that describes the image contents effectively. Comprehensive experimental evaluation demonstrate that the proposed framework integrating the sparseness property of images, adaptive dictionary training and iterative deblurring scheme together significantly improves the deblurring performance and is comparable with the state-of-the art deblurring algorithms and seeks a powerful solution to an ill-conditioned inverse problem.

  13. Hazardous Continuation Backward in Time in Nonlinear Parabolic Equations, and an Experiment in Deblurring Nonlinearly Blurred Imagery.

    Science.gov (United States)

    Carasso, Alfred S

    2013-01-01

    Identifying sources of ground water pollution, and deblurring nanoscale imagery as well as astronomical galaxy images, are two important applications involving numerical computation of parabolic equations backward in time. Surprisingly, very little is known about backward continuation in nonlinear parabolic equations. In this paper, an iterative procedure originating in spectroscopy in the 1930's, is adapted into a useful tool for solving a wide class of 2D nonlinear backward parabolic equations. In addition, previously unsuspected difficulties are uncovered that may preclude useful backward continuation in parabolic equations deviating too strongly from the linear, autonomous, self adjoint, canonical model. This paper explores backward continuation in selected 2D nonlinear equations, by creating fictitious blurred images obtained by using several sharp images as initial data in these equations, and capturing the corresponding solutions at some positive time T. Successful backward continuation from t=T to t = 0, would recover the original sharp image. Visual recognition provides meaningful evaluation of the degree of success or failure in the reconstructed solutions. Instructive examples are developed, illustrating the unexpected influence of certain types of nonlinearities. Visually and statistically indistinguishable blurred images are presented, with vastly different deblurring results. These examples indicate that how an image is nonlinearly blurred is critical, in addition to the amount of blur. The equations studied represent nonlinear generalizations of Brownian motion, and the blurred images may be interpreted as visually expressing the results of novel stochastic processes.

  14. Use of biaxially oriented polypropylene film for evaluating and cleaning contaminated atomic force microscopy probe tips: An application to blind tip reconstruction

    Science.gov (United States)

    Nie, H.-Y.; Walzak, M. J.; McIntyre, N. S.

    2002-11-01

    An atomic force microscopy (AFM) image of a surface is basically a convolution of the probe tip geometry and the surface features; it is important to know this tip effect to ensure that an image truly reflects the surface features. We have found that a biaxially oriented polypropylene (BOPP) film is suitable for checking tip performance and for cleaning contaminated tips, thus making it possible to collect images of the same area of a BOPP film surface before and after the tip was cleaned. Therefore, the difference between the two different images is solely due to the contamination of the tip. We took advantage of our ability to collect AFM images of the same area using the same tip, in one instance, contaminated and, in the other, after being cleaned. First we used blind reconstruction on the image collected using the contaminated tip. Blind tip reconstruction allows one to extract the geometry of the tip from a given image. Once we had estimated the geometry of the contaminated tip, we used it to simulate the tip effect using the image collected using the cleaned tip. By comparing the simulation result with the image collected using the contaminated tip we showed that the blind reconstruction routine works well. Prior to this, there was no de facto method for testing blind reconstruction algorithms.

  15. Wavelet Decomposition Method for $L_2/$/TV-Image Deblurring

    KAUST Repository

    Fornasier, M.

    2012-07-17

    In this paper, we show additional properties of the limit of a sequence produced by the subspace correction algorithm proposed by Fornasier and Schönlieb [SIAM J. Numer. Anal., 47 (2009), pp. 3397-3428 for L 2/TV-minimization problems. An important but missing property of such a limiting sequence in that paper is the convergence to a minimizer of the original minimization problem, which was obtained in [M. Fornasier, A. Langer, and C.-B. Schönlieb, Numer. Math., 116 (2010), pp. 645-685 with an additional condition of overlapping subdomains. We can now determine when the limit is indeed a minimizer of the original problem. Inspired by the work of Vonesch and Unser [IEEE Trans. Image Process., 18 (2009), pp. 509-523], we adapt and specify this algorithm to the case of an orthogonal wavelet space decomposition for deblurring problems and provide an equivalence condition to the convergence of such a limiting sequence to a minimizer. We also provide a counterexample of a limiting sequence by the algorithm that does not converge to a minimizer, which shows the necessity of our analysis of the minimizing algorithm. © 2012 Society for Industrial and Applied Mathematics.

  16. Deblurring, Localization and Geometry Correction of 2D QR Bar Codes Using Richardson Lucy Method

    Directory of Open Access Journals (Sweden)

    Manpreet Kaur

    2014-09-01

    Full Text Available This paper includes the recognition of 2D QR bar codes. This paper describes the deblurring, localization and geometry correction of 2D QR bar codes. The images captured are blurred due motion between the image and the camera. Hence the image containing the QR barcode cannot be read by QR reader. To make the QR barcode readable the images are need to be deblurred. Lucy Richardson method and Weiner Deconvolution Method is used to deblurr and localize the bar code. From both of the methods Lucy Richardson Method is best because this method takes less time for execution than the other method. Simulink Model is used for the Geometry correction of the QR bar code. In future, we would like to investigate the generalization of our algorithm to handle more complicated motion blur.

  17. Anisotropic Total Variation Regularized L^1-Approximation and Denoising/Deblurring of 2D Bar Codes

    CERN Document Server

    Choksi, Rustum; Oberman, Adam

    2010-01-01

    We consider variations of the Rudin-Osher-Fatemi functional which are particularly well-suited to denoising and deblurring of 2D bar codes. These functionals consist of an anisotropic total variation favoring rectangles and a fidelity term which measure the L^1 distance to the signal, both with and without the presence of a deconvolution operator. Based upon the existence of a certain associated vector field, we find necessary and sufficient conditions for a function to be a minimizer. We apply these results to 2D bar codes to find explicit regimes ---in terms of the fidelity parameter and smallest length scale of the bar codes--- for which a perfect bar code is recoverable via minimization of the functionals. Via a discretization reformulated as a linear program, we perform numerical experiments for all functionals demonstrating their denoising and deblurring capabilities.

  18. Deblurring Texture Extraction from Digital Aerial Image by Reforming "Steep Edge" Curve

    Institute of Scientific and Technical Information of China (English)

    WU Jun; CHEN Danqing

    2005-01-01

    Texture extract from digital aerial image is widely used in three-dimensional city modeling to generate "photo-realistic" views. In this paper, a method based on reforming "Steep edge" curve, which clearly explains how the diffraction of the sunlight makes digital aerial image blurring, is proposed to deblur the texture extraction from digital aerial image, and the experiment shows a good result in visualization and automation.

  19. Algorithms and software for total variation image reconstruction via first-order methods

    DEFF Research Database (Denmark)

    Dahl, Joahim; Hansen, Per Christian; Jensen, Søren Holdt

    2010-01-01

    This paper describes new algorithms and related software for total variation (TV) image reconstruction, more specifically: denoising, inpainting, and deblurring. The algorithms are based on one of Nesterov's first-order methods, tailored to the image processing applications in such a way that...

  20. Reconstruction

    Directory of Open Access Journals (Sweden)

    Stefano Zurrida

    2011-01-01

    Full Text Available Breast cancer is the most common cancer in women. Primary treatment is surgery, with mastectomy as the main treatment for most of the twentieth century. However, over that time, the extent of the procedure varied, and less extensive mastectomies are employed today compared to those used in the past, as excessively mutilating procedures did not improve survival. Today, many women receive breast-conserving surgery, usually with radiotherapy to the residual breast, instead of mastectomy, as it has been shown to be as effective as mastectomy in early disease. The relatively new skin-sparing mastectomy, often with immediate breast reconstruction, improves aesthetic outcomes and is oncologically safe. Nipple-sparing mastectomy is newer and used increasingly, with better acceptance by patients, and again appears to be oncologically safe. Breast reconstruction is an important adjunct to mastectomy, as it has a positive psychological impact on the patient, contributing to improved quality of life.

  1. Motion de-blurring by second-order intensity-correlated imaging

    Institute of Scientific and Technical Information of China (English)

    Zunwang Bo; Wenlin Gong; Shensheng Han

    2016-01-01

    For a Hanbury Brown and Twiss system,the influence of relative motion between the object and the detection plane on the resolution of second-order intensity-correlated imaging is investigated.The analytical results,which are backed up by experiments,demonstrate that the amplitude and mode of the object's motion have no effect on the second-order intensity-correlated imaging and that high-resolution imaging can be always achieved by using a phase-retrieval method from the diffraction patterns.The use of motion de-blurring imaging for this approach is also discussed.

  2. A trust region-CG algorithm for deblurring problem inatmospheric image reconstruction

    Institute of Scientific and Technical Information of China (English)

    WANG; Yanfei(王彦飞); YUAN; Yaxiang(袁亚湘); ZHANG; Hongchao(张洪超)

    2002-01-01

    In this paper we solve large scale ill-posed problems, particularly the image restoration problem in atmospheric imaging sciences, by a trust region-CG algorithm. Image restoration involves the removal or minimization of degradation (blur, clutter, noise, etc.) in an image using a priori knowledge about the degradation phenomena. Our basic technique is the so-called trust region method, while the subproblem is solved by the truncated conjugate gradient method, which has been well developed for well-posed problems.The trust region method, due to its robustness in global convergence, seems to be a promising way to deal with ill-posed problems.

  3. An Improved Adaptive Deconvolution Algorithm for Single Image Deblurring

    Directory of Open Access Journals (Sweden)

    Hsin-Che Tsai

    2014-01-01

    Full Text Available One of the most common defects in digital photography is motion blur caused by camera shake. Shift-invariant motion blur can be modeled as a convolution of the true latent image and a point spread function (PSF with additive noise. The goal of image deconvolution is to reconstruct a latent image from a degraded image. However, ringing is inevitable artifacts arising in the deconvolution stage. To suppress undesirable artifacts, regularization based methods have been proposed using natural image priors to overcome the ill-posedness of deconvolution problem. When the estimated PSF is erroneous to some extent or the PSF size is large, conventional regularization to reduce ringing would lead to loss of image details. This paper focuses on the nonblind deconvolution by adaptive regularization which preserves image details, while suppressing ringing artifacts. The way is to control the regularization weight adaptively according to the image local characteristics. We adopt elaborated reference maps that indicate the edge strength so that textured and smooth regions can be distinguished. Then we impose an appropriate constraint on the optimization process. The experiments’ results on both synthesized and real images show that our method can restore latent image with much fewer ringing and favors the sharp edges.

  4. An MLP Neural Net with L1 and L2 Regularizers for Real Conditions of Deblurring

    Directory of Open Access Journals (Sweden)

    Bernués Emiliano

    2010-01-01

    Full Text Available Abstract Real conditions of deblurring involve a spatially nonlinear process since the borders are truncated, causing significant artifacts in the restored results. Typically, it is assumed to have boundary conditions to reduce ringing; in contrast, this paper proposes a restoration method which simply deals with null borders. We minimize a deterministic regularized function in a Multilayer Perceptron (MLP with no training and follow a back-propagation algorithm with the L1 and L2 norm-based regularizers. As a result, the truncated borders are regenerated while adapting the center of the image to the optimum linear solution. We report experimental results showing the good performance of our approach in a real model without borders. Even if using boundary conditions, the quality of restoration is comparable to other recent researches.

  5. A method for space-variant deblurring with application to adaptive optics imaging in astronomy

    CERN Document Server

    La Camera, Andrea; Diolaiti, Emiliano; Boccacci, Patrizia; Bertero, Mario; Bellazzini, Michele; Ciliegi, Paolo

    2015-01-01

    Images from adaptive optics systems are generally affected by significant distortions of the point spread function (PSF) across the field of view, depending on the position of natural and artificial guide stars. Image reduction techniques circumventing or mitigating these effects are important tools to take full advantage of the scientific information encoded in AO images. The aim of this paper is to propose a method for the deblurring of the astronomical image, given a set of samples of the space-variant PSF. The method is based on a partitioning of the image domain into regions of isoplanatism and on applying suitable deconvolution methods with boundary effects correction to each region. The effectiveness of the boundary effects correction is proved. Moreover, the criterion for extending the disjoint sections to partially overlapping sections is validated. The method is applied to simulated images of a stellar system characterized by a spatially variable PSF. We obtain good photometric quality, and therefor...

  6. Willed blindness

    DEFF Research Database (Denmark)

    Gjerris, Mickey

    2015-01-01

    This article describes how we seem to live in a willed blindness towards the effects that our meat production and consumption have on animals, the environment and the climate. A willed blindness that cannot be explained by either lack of knowledge or scientific uncertainty. The blindness enables us...... blindness focusing on the development of either a new moral vision of our obligations or new visions of what a good life is....

  7. Color Blindness

    Institute of Scientific and Technical Information of China (English)

    严双红

    2007-01-01

    About one in 12 boys is color-blind, and one in every 400 girls, so in each school class there are likely to be at least one or two people who are color-blind. Because they are color- blind from birth, most people do not know that they are color-

  8. Color blindness

    Science.gov (United States)

    ... color blindness often have problems seeing reds and greens, too. The most severe form of color blindness is achromatopsia. This is a rare condition in which a person cannot see any color, only shades of gray. Most color blindness is due to ...

  9. Least-squares migration of multisource data with a deblurring filter

    KAUST Repository

    Dai, Wei

    2011-09-01

    Least-squares migration (LSM) has been shown to be able to produce high-quality migration images, but its computational cost is considered to be too high for practical imaging. We have developed a multisource least-squares migration algorithm (MLSM) to increase the computational efficiency by using the blended sources processing technique. To expedite convergence, a multisource deblurring filter is used as a preconditioner to reduce the data residual. This MLSM algorithm is applicable with Kirchhoff migration, wave-equation migration, or reverse time migration, and the gain in computational efficiency depends on the choice of migration method. Numerical results with Kirchhoff LSM on the 2D SEG/EAGE salt model show that an accurate image is obtained by migrating a supergather of 320 phase-encoded shots. When the encoding functions are the same for every iteration, the input/output cost of MLSM is reduced by 320 times. Empirical results show that the crosstalk noise introduced by blended sources is more effectively reduced when the encoding functions are changed at every iteration. The analysis of signal-to-noise ratio (S/N) suggests that not too many iterations are needed to enhance the S/N to an acceptable level. Therefore, when implemented with wave-equation migration or reverse time migration methods, the MLSM algorithm can be more efficient than the conventional migration method. © 2011 Society of Exploration Geophysicists.

  10. Defocus Deblurring and Superresolution for Time-of-Flight Depth Cameras

    KAUST Repository

    Xiao, Lei

    2015-06-07

    Continuous-wave time-of-flight (ToF) cameras show great promise as low-cost depth image sensors in mobile applications. However, they also suffer from several challenges, including limited illumination intensity, which mandates the use of large numerical aperture lenses, and thus results in a shallow depth of field, making it difficult to capture scenes with large variations in depth. Another shortcoming is the limited spatial resolution of currently available ToF sensors. In this paper we analyze the image formation model for blurred ToF images. By directly working with raw sensor measurements but regularizing the recovered depth and amplitude images, we are able to simultaneously deblur and super-resolve the output of ToF cameras. Our method outperforms existing methods on both synthetic and real datasets. In the future our algorithm should extend easily to cameras that do not follow the cosine model of continuous-wave sensors, as well as to multi-frequency or multi-phase imaging employed in more recent ToF cameras.

  11. Adaptive correction procedure for TVL1 image deblurring under impulse noise

    Science.gov (United States)

    Bai, Minru; Zhang, Xiongjun; Shao, Qianqian

    2016-08-01

    For the problem of image restoration of observed images corrupted by blur and impulse noise, the widely used TVL1 model may deviate from both the data-acquisition model and the prior model, especially for high noise levels. In order to seek a solution of high recovery quality beyond the reach of the TVL1 model, we propose an adaptive correction procedure for TVL1 image deblurring under impulse noise. Then, a proximal alternating direction method of multipliers (ADMM) is presented to solve the corrected TVL1 model and its convergence is also established under very mild conditions. It is verified by numerical experiments that our proposed approach outperforms the TVL1 model in terms of signal-to-noise ratio (SNR) values and visual quality, especially for high noise levels: it can handle salt-and-pepper noise as high as 90% and random-valued noise as high as 70%. In addition, a comparison with a state-of-the-art method, the two-phase method, demonstrates the superiority of the proposed approach.

  12. DE-BLURRING SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY IMAGES USING WAVELET DECOMPOSITION

    Directory of Open Access Journals (Sweden)

    Neethu M. Sasi

    2016-02-01

    Full Text Available Single photon emission computed tomography imaging is a popular nuclear medicine imaging technique which generates images by detecting radiations emitted by radioactive isotopes injected in the human body. Scattering of these emitted radiations introduces blur in this type of images. This paper proposes an image processing technique to enhance cardiac single photon emission computed tomography images by reducing the blur in the image. The algorithm works in two main stages. In the first stage a maximum likelihood estimate of the point spread function and the true image is obtained. In the second stage Lucy Richardson algorithm is applied on the selected wavelet coefficients of the true image estimate. The significant contribution of this paper is that processing of images is done in the wavelet domain. Pre-filtering is also done as a sub stage to avoid unwanted ringing effects. Real cardiac images are used for the quantitative and qualitative evaluations of the algorithm. Blur metric, peak signal to noise ratio and Tenengrad criterion are used as quantitative measures. Comparison against other existing de-blurring algorithms is also done. The simulation results indicate that the proposed method effectively reduces blur present in the image.

  13. WE-G-204-04: Focal Spot Deblurring For High Resolution Amorphous Selenium (aSe) Complementary Metal Oxide Semiconductor (CMOS) X-Ray Detector

    Energy Technology Data Exchange (ETDEWEB)

    Nagesh, S Setlur; Rana, R; Russ, M; Ionita, C; Bednarek, D; Rudin, S [Toshiba Stroke and Vascular Research Center, University at Buffalo, SUNY (United States)

    2015-06-15

    Purpose: CMOS-based aSe detectors compared to CsI-TFT-based flat panels have the advantages of higher spatial sampling due to smaller pixel size and decreased blurring characteristic of direct rather than indirect detection. For systems with such detectors, the limiting factor degrading image resolution then becomes the focal-spot geometric unsharpness. This effect can seriously limit the use of such detectors in areas such as cone beam computed tomography, clinical fluoroscopy and angiography. In this work a technique to remove the effect of focal-spot blur is presented for a simulated aSe detector. Method: To simulate images from an aSe detector affected with focal-spot blur, first a set of high-resolution images of a stent (FRED from Microvention, Inc.) were acquired using a 75µm pixel size Dexela-Perkin-Elmer detector and averaged to reduce quantum noise. Then the averaged image was blurred with a known Gaussian blur at two different magnifications to simulate an idealized focal spot. The blurred images were then deconvolved with a set of different Gaussian blurs to remove the effect of focal-spot blurring using a threshold-based, inverse-filtering method. Results: The blur was removed by deconvolving the images using a set of Gaussian functions for both magnifications. Selecting the correct function resulted in an image close to the original; however, selection of too wide a function would cause severe artifacts. Conclusion: Experimentally, focal-spot blur at different magnifications can be measured using a pin hole with a high resolution detector. This spread function can be used to deblur the input images that are acquired at corresponding magnifications to correct for the focal spot blur. For CBCT applications, the magnification of specific objects can be obtained using initial reconstructions then corrected for focal-spot blurring to improve resolution. Similarly, if object magnification can be determined such correction may be applied in fluoroscopy and

  14. [Cortical blindness].

    Science.gov (United States)

    Chokron, S

    2014-02-01

    Cortical blindness refers to a visual loss induced by a bilateral occipital lesion. The very strong cooperation between psychophysics, cognitive psychology, neurophysiology and neuropsychology these latter twenty years as well as recent progress in cerebral imagery have led to a better understanding of neurovisual deficits, such as cortical blindness. It thus becomes possible now to propose an earlier diagnosis of cortical blindness as well as new perspectives for rehabilitation in children as well as in adults. On the other hand, studying complex neurovisual deficits, such as cortical blindness is a way to infer normal functioning of the visual system.

  15. Sparse Reconstruction for Micro Defect Detection in Acoustic Micro Imaging

    Directory of Open Access Journals (Sweden)

    Yichun Zhang

    2016-10-01

    Full Text Available Acoustic micro imaging has been proven to be sufficiently sensitive for micro defect detection. In this study, we propose a sparse reconstruction method for acoustic micro imaging. A finite element model with a micro defect is developed to emulate the physical scanning. Then we obtain the point spread function, a blur kernel for sparse reconstruction. We reconstruct deblurred images from the oversampled C-scan images based on l1-norm regularization, which can enhance the signal-to-noise ratio and improve the accuracy of micro defect detection. The method is further verified by experimental data. The results demonstrate that the sparse reconstruction is effective for micro defect detection in acoustic micro imaging.

  16. Blind Masseurs

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    Guan Enming and his wife Hao Dejuan, a blind couple, vowed to "never become a burden for society." The couple retired from the QJngdao Massotherapy Hospital in 1992, and thereafter opened a private clinic with assistance from their

  17. Blind Ambition

    Science.gov (United States)

    Olson, Catherine Applefeld

    2009-01-01

    No matter how dedicated they may be, some teachers are daunted by extreme challenges. Carol Agler, music director at the Ohio State School for the Blind (OSSB), is not one of those teachers. Since joining the OSSB staff 11 years ago, Agler has revived the school's long-dormant band program and created its first marching band. Next January, she…

  18. Blind super-resolution reconstruction method based on maximum a posterior estimation%基于最大后验估计的影像盲超分辨率重建方法

    Institute of Scientific and Technical Information of China (English)

    张洪艳; 沈焕锋; 张良培; 李平湘; 袁强强

    2011-01-01

    In this paper, a new joint Maximum A Posterior (MAP) formulation was proposed to integrate image registration into blind image Super-Resolution (SR) reconstruction to reduce image registration errors. The formulation was built upon the MAP framework, which judiciously combined image registration, blur identification and SR. A cyclic coordinate descent optimization procedure was developed to solve the MAP formulation, in which the registration parameters, blurring function and High Resolution (HR) image were estimated in an alternative manner given to the two others, respectively. The experimental results indicate that the proposed algorithm has considerable effectiveness in terms of both quantitative measurement and visual evaluation.%为了减小配准误差对盲超分辨率重建的影响,提出了一种影像配准和盲超分辨率重建联合处理的模型与方法.将配准参数、模糊函数和高分辨率影像建立在统一的最大后验估计模型框架内,并利用循环坐标下降最优化策略对模型进行求解,从而实现了配准参数、模糊函数和高分辨率影像的联合求解.实验结果证明:与传统盲超分辨率重建算法相比,该算法能够有效减少重建影像中的伪痕,在视觉评估上和定量评价上均能得到更好的结果.

  19. Learning High-Order Filters for Efficient Blind Deconvolution of Document Photographs

    KAUST Repository

    Xiao, Lei

    2016-09-16

    Photographs of text documents taken by hand-held cameras can be easily degraded by camera motion during exposure. In this paper, we propose a new method for blind deconvolution of document images. Observing that document images are usually dominated by small-scale high-order structures, we propose to learn a multi-scale, interleaved cascade of shrinkage fields model, which contains a series of high-order filters to facilitate joint recovery of blur kernel and latent image. With extensive experiments, we show that our method produces high quality results and is highly efficient at the same time, making it a practical choice for deblurring high resolution text images captured by modern mobile devices. © Springer International Publishing AG 2016.

  20. Phase retrieval deblurring for imaging of dense object within a low scattering soft biological tissue

    Science.gov (United States)

    Shalev, Maya Aviv; Rivenson, Yair; Meiri, Amihai; Zalevsky, Zeev

    2016-09-01

    Tissues are characterized by a strong scattering of visible optical radiation, which prevents one from achieving deep-tissue imaging. We propose a computational imaging technique for the inference of specific macroscopic, spatial phase distribution features of the scattering media. The spatial phase distribution is reconstructed from several defocused intensity images. We empirically demonstrate the method by reconstructing the location of two fibula chicken bones, embedded within chicken breast tissue. The suggested technique is safe, using visible laser illumination, and noninvasive. It is also cost-effective since a simple optical system is used and the images are acquired using a conventional camera, and it does not require interferometric detection as well as direct access to the object in absence of the layer.

  1. Blind Quantum Signature with Blind Quantum Computation

    Science.gov (United States)

    Li, Wei; Shi, Ronghua; Guo, Ying

    2016-12-01

    Blind quantum computation allows a client without quantum abilities to interact with a quantum server to perform a unconditional secure computing protocol, while protecting client's privacy. Motivated by confidentiality of blind quantum computation, a blind quantum signature scheme is designed with laconic structure. Different from the traditional signature schemes, the signing and verifying operations are performed through measurement-based quantum computation. Inputs of blind quantum computation are securely controlled with multi-qubit entangled states. The unique signature of the transmitted message is generated by the signer without leaking information in imperfect channels. Whereas, the receiver can verify the validity of the signature using the quantum matching algorithm. The security is guaranteed by entanglement of quantum system for blind quantum computation. It provides a potential practical application for e-commerce in the cloud computing and first-generation quantum computation.

  2. Blind Quantum Signature with Blind Quantum Computation

    Science.gov (United States)

    Li, Wei; Shi, Ronghua; Guo, Ying

    2017-04-01

    Blind quantum computation allows a client without quantum abilities to interact with a quantum server to perform a unconditional secure computing protocol, while protecting client's privacy. Motivated by confidentiality of blind quantum computation, a blind quantum signature scheme is designed with laconic structure. Different from the traditional signature schemes, the signing and verifying operations are performed through measurement-based quantum computation. Inputs of blind quantum computation are securely controlled with multi-qubit entangled states. The unique signature of the transmitted message is generated by the signer without leaking information in imperfect channels. Whereas, the receiver can verify the validity of the signature using the quantum matching algorithm. The security is guaranteed by entanglement of quantum system for blind quantum computation. It provides a potential practical application for e-commerce in the cloud computing and first-generation quantum computation.

  3. Blind system identification

    OpenAIRE

    Abed-Meriam, Karim; Qui, Wanzhi; Hua, Yingbo

    1997-01-01

    Blind system identification (BSI) is a fundamental signal processing technology aimed at retrieving a system's unknown information from its output only. This technology has a wide range of possible applications such as mobile communications, speech reverberation cancellation, and blind image restoration. This paper reviews a number of recently developed concepts and techniques for BSI, which include the concept of blind system identifiability in a deterministic framework, the blind techniques...

  4. ACL reconstruction

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007208.htm ACL reconstruction To use the sharing features on this page, please enable JavaScript. ACL reconstruction is surgery to reconstruct the ligament in ...

  5. Blindness and vision loss

    Science.gov (United States)

    ... means you cannot see anything and DO NOT see light. (Most people who use the term "blindness" mean ... the vision loss. For long-term vision loss, see a low-vision specialist, who can help you learn to care for yourself and ... of vision; No light perception (NLP); Low vision; Vision loss and blindness ...

  6. Blindness%失明

    Institute of Scientific and Technical Information of China (English)

    李同良

    2009-01-01

    @@ There was a blind girl who hated herself because she was blind. She hated everyone,except her loving boyfriend who was always there for her. She told her boyfriend, "If I could only see the World, I will marry you."

  7. Blindness and Yoga

    Science.gov (United States)

    Heyes, Anthony David

    1974-01-01

    Evidence is presented to support the claims that, among many blind persons, physical inactivity leads to poor physical fitness; that a state of anxiety is often a concomitant of unguided blind mobility; and that Yogic practices offer a solution to both difficulties. (GW)

  8. "Color-Blind" Racism.

    Science.gov (United States)

    Carr, Leslie G.

    Examining race relations in the United States from a historical perspective, this book explains how the constitution is racist and how color blindness is actually a racist ideology. It is argued that Justice Harlan, in his dissenting opinion in Plessy v. Ferguson, meant that the constitution and the law must remain blind to the existence of race…

  9. Blind Pre-School.

    Science.gov (United States)

    Taylor, Billie, Comp.

    Articles pertinent to aiding the pre-school blind child are collected in this publication. Topics include discussion of attitudes and emotional reactions important for parents and teachers of blind children, and optimal development in regard to early motor behavior and emotional and social needs. Common areas of parental concern such as discipline…

  10. Models for the blind

    DEFF Research Database (Denmark)

    Olsén, Jan-Eric

    2014-01-01

    When displayed in museum cabinets, tactile objects that were once used in the education of blind and visually impaired people, appear to us, sighted visitors, as anything but tactile. We cannot touch them due to museum policies and we can hardly imagine what it would have been like for a blind...... person to touch them in their historical context. And yet these objects are all about touch, from the concrete act of touching something to the norms that assigned touch a specific pedagogical role in nineteenth-century blind schools. The aim of this article is twofold. First, I provide a historical...... background to the tactile objects of the blind. When did they appear as a specific category of pedagogical aid and how did they help determine the relation between blindness, vision, and touch? Second, I address the tactile objects from the point of view of empirical sources and historical evidence. Material...

  11. Superresolution Reconstruction of Video Sequence Using a Coarse-to-Fine Registration and Optimal Interpolation Strategy

    Directory of Open Access Journals (Sweden)

    Zunshang Zhu

    2013-05-01

    Full Text Available In this paper, a novel video superresolution (SR reconstruction approach using a coarse‐to‐fine registration and optimal interpolation strategy is proposed. Firstly, initial correspondence between two consecutive frames is identified by scale invariant feature transform (SIFT features under the homography transformation model. Then, a least square matching (LSM method is employed to achieve a high‐precision estimation of homography. Finally, optimal interpolation using the iterative back projection‐based deblurring method was designed to obtain a high‐resolution grid interpolation and to improve the visual quality of the final SR results. The experiment results demonstrate that the proposed method provides an available SR approach in engineering applications.

  12. Compressed Blind De-convolution

    CERN Document Server

    Saligrama, V

    2009-01-01

    Suppose the signal x is realized by driving a k-sparse signal u through an arbitrary unknown stable discrete-linear time invariant system H. These types of processes arise naturally in Reflection Seismology. In this paper we are interested in several problems: (a) Blind-Deconvolution: Can we recover both the filter $H$ and the sparse signal $u$ from noisy measurements? (b) Compressive Sensing: Is x compressible in the conventional sense of compressed sensing? Namely, can x, u and H be reconstructed from a sparse set of measurements. We develop novel L1 minimization methods to solve both cases and establish sufficient conditions for exact recovery for the case when the unknown system H is auto-regressive (i.e. all pole) of a known order. In the compressed sensing/sampling setting it turns out that both H and x can be reconstructed from O(k log(n)) measurements under certain technical conditions on the support structure of u. Our main idea is to pass x through a linear time invariant system G and collect O(k lo...

  13. Static analysis for blinding

    DEFF Research Database (Denmark)

    Nielsen, Christoffer Rosenkilde; Nielson, Hanne Riis

    2006-01-01

    operation blinding. In this paper we study the theoretical foundations for one of the successful approaches to validating cryptographic protocols and we extend it to handle the blinding primitive. Our static analysis approach is based on Flow Logic; this gives us a clean separation between the specification...... of the analysis and its realisation in an automatic tool. We concentrate on the former in the present paper and provide the semantic foundation for our analysis of protocols using blinding - also in the presence of malicious attackers....

  14. Deblurring of QR Code Images by Linear CNN%线性CNN用于QR码图像去模糊化处理

    Institute of Scientific and Technical Information of China (English)

    刘砚一; 胡洁; 刘红英

    2012-01-01

    摘要在物联网时代中,QR码的应用非常广泛,QR码图像的去模糊研究具有重要的实际意义.细胞神经网络(CNN)以其高速并行处理、二值输入输出、便于电路实现等特性,在图像处理中有着广泛的应用,文章在分析了图像去模糊化理论基础上,采用线性CNN构造图像的去模糊化模型,实现了模糊图像的恢复.通过实验比较,在相同参数条件下,线性CNN去模糊化模型对含噪模糊图像的恢复效果更好,鲁棒性更高.%In the periods of the Internet of things, the applications of QR code are extensive. The researches about deblurring of QR code images are important. The CNN used in images processing with its superior characteristic in high speed parallel processing; binary inputs and outputs and suitable for on-chip implementations. In this paper, we used linear CNN system to construct the delurring module to recover the degraded images. With comparing the results of experiment, the module of linear CNN get the better result for including noise degraded images.

  15. Vision - night blindness

    Science.gov (United States)

    ... People with night blindness often have trouble seeing stars on a clear night or walking through a ... certain drugs Vitamin A deficiency (rare) Nontreatable causes: Birth defects Retinitis pigmentosa

  16. Blind Loop Syndrome

    Science.gov (United States)

    ... more commonly result from other conditions such as short bowel syndrome or chronic pancreatitis. Small intestine aspirate and fluid ... people with severe blind loop syndrome resulting in short bowel syndrome. References Townsend CM Jr, et al. Sabiston Textbook ...

  17. Visual Impairment, Including Blindness

    Science.gov (United States)

    ... Who Knows What? Survey Item Bank Search for: Visual Impairment, Including Blindness Links updated, April 2017 En ... doesn’t wear his glasses. Back to top Visual Impairments in Children Vision is one of our ...

  18. Blind loop syndrome

    Science.gov (United States)

    ... part of the stomach) and operations for extreme obesity As a complication of inflammatory bowel disease Diseases such as diabetes or scleroderma may slow down movement in a segment of the intestine, leading to blind loop syndrome.

  19. Blind Compressed Sensing Reconstruction of Speech Signal Based on Block Diagonal Structure%基于块对角结构的语音信号盲压缩重构

    Institute of Scientific and Technical Information of China (English)

    陈莹; 钟菲; 郭树旭; 陈孝君

    2016-01-01

    为在复杂环境中提高语音信号的重构精度,提出基于正交块对角结构的语音信号盲压缩重构算法,通过最优求解找到一组对应的正交块对角变换基及稀疏矩阵,利用二者乘积实现语音信号压缩重构.该算法确保盲压缩感知理论具有唯一解,能从复杂的环境中恢复原始语音信号,具有更强的自适应性,在保证听觉效果的同时,大大降低了观测维度.实验结果表明,基于正交块对角结构盲压缩感知(OBD-BCS:Orthonormal Block Diagonal Blind Compressed Sensing)算法能高质量恢复语音信号原始结构.

  20. A Blind Date

    Institute of Scientific and Technical Information of China (English)

    周立

    2003-01-01

    英语对话:A: Talking about girls, I still remember my first time to meet my girlfriend. Iwas so clumsy and very nervous.B: That’s the same case with me. I had the jitters at my blind date, too.A: Did you also meet your girlfriend at a blind date?B: Yeah. I was actually very shy of speaking to girls, you know?

  1. Models for the Blind

    Directory of Open Access Journals (Sweden)

    Jan Eric Olsén

    2014-10-01

    Full Text Available When displayed in museum cabinets, tactile objects that were once used in the education of blind and visually impaired people, appear to us, sighted visitors, as anything but tactile. We cannot touch them due to museum policies and we can hardly imagine what it would have been like for a blind person to touch them in their historical context. And yet these objects are all about touch, from the concrete act of touching something to the norms that assigned touch a specific pedagogical role in nineteenth-century blind schools. The aim of this article is twofold. First, I provide a historical background to the tactile objects of the blind. When did they appear as a specific category of pedagogical aid and how did they help determine the relation between blindness, vision, and touch? Second, I address the tactile objects from the point of view of empirical sources and historical evidence. Material objects are rarely used as historical testimonies for the simple reason that they, unlike archival material, do not present historians with written documents that can be held as evidence of the past. However, as I point out, certain historical questions of which archives remain silent could be approached by other means such as the use of material objects. Rather than delivering concrete methodological suggestions, this second part reflects upon the historical use of material objects - both their possibilities and their limits - within the context of blindness.

  2. Blind Stereoscopy of the Coronal Magnetic Field

    CERN Document Server

    Aschwanden, Markus J; Malanushenko, Anna

    2015-01-01

    We test the feasibility of 3D coronal-loop tracing in stereoscopic EUV image pairs, with the ultimate goal of enabling efficient 3D reconstruction of the coronal magnetic field that drives flares and coronal mass ejections (CMEs). We developed an automated code designed to perform triangulation of coronal loops in pairs (or triplets) of EUV images recorded from different perspectives. The automated (or blind) stereoscopy code includes three major tasks: (i) automated pattern recognition of coronal loops in EUV images, (ii) automated pairing of corresponding loop patterns from two different aspect angles, and (iii) stereoscopic triangulation of 3D loop coordinates. We perform tests with simulated stereoscopic EUV images and quantify the accuracy of all three procedures. In addition we test the performance of the blind stereoscopy code as a function of the spacecraft-separation angle and as a function of the spatial resolution. We also test the sensitivity to magnetic non-potentiality. The automated code develo...

  3. Blind iterative deconvolution of binary star images

    CERN Document Server

    Saha, S K

    1997-01-01

    The technique of Blind Iterative De-convolution (BID) was used to remove the atmospherically induced point spread function (PSF) from short exposure images of two binary stars, HR 5138 and HR 5747 obtained at the cassegrain focus of the 2.34 meter Vainu Bappu Telescope(VBT), situated at Vainu Bappu Observatory (VBO), Kavalur. The position angles and separations of the binary components were seen to be consistent with results of the auto-correlation technique, while the Fourier phases of the reconstructed images were consistent with published observations of the binary orbits.

  4. Models for the Blind

    OpenAIRE

    Jan Eric Olsén

    2014-01-01

    When displayed in museum cabinets, tactile objects that were once used in the education of blind and visually impaired people, appear to us, sighted visitors, as anything but tactile. We cannot touch them due to museum policies and we can hardly imagine what it would have been like for a blind person to touch them in their historical context. And yet these objects are all about touch, from the concrete act of touching something to the norms that assigned touch a specific pedagogical role in n...

  5. Penile reconstruction

    Institute of Scientific and Technical Information of China (English)

    Giulio Garaffa; Salvatore Sansalone; David J Ralph

    2013-01-01

    During the most recent years,a variety of new techniques of penile reconstruction have been described in the literature.This paper focuses on the most recent advances in male genital reconstruction after trauma,excision of benign and malignant disease,in gender reassignment surgery and aphallia with emphasis on surgical technique,cosmetic and functional outcome.

  6. Oplysningens blinde vinkler

    DEFF Research Database (Denmark)

    Hansen, Pelle Guldborg; Hendricks, Vincent Fella

    manipulation og fordrejning, til at påvirke menneskers overvejelser, beslutninger og handlinger, både individuelt og kollektivt, hvilket i sidste ende kan få betydning for de demokratiske processer. Oplysningens blinde vinkler gennemgår en række informationsfænomener, som optræder i vores dagligdag, og den...

  7. Oplysnigens blinde vinkler

    DEFF Research Database (Denmark)

    Hendricks, Vincent Fella; Hansen, Pelle Guldborg

    manipulation og fordrejning, til at påvirke menneskers overvejelser, beslutninger og handlinger, både individuelt og kollektivt, hvilket i sidste ende kan få betydning for de demokratiske processer. Oplysningens blinde vinkler gennemgår en række informationsfænomener, som optræder i vores dagligdag, og den...

  8. The blind hens’ challenge

    DEFF Research Database (Denmark)

    Sandøe, Peter; Hocking, Paul M.; Forkman, Björn

    2014-01-01

    repellent, yet 'welfare-only' positions appear to be committed to endorsing this possibility if it produces welfare gains. We call this the 'Blind Hens' Challenge'. In this paper, we argue that there are both empirical and theoretical reasons why even those adopting 'welfare-only' views should be concerned...

  9. Corneal blindness and xenotransplantation.

    Science.gov (United States)

    Lamm, Vladimir; Hara, Hidetaka; Mammen, Alex; Dhaliwal, Deepinder; Cooper, David K C

    2014-01-01

    Approximately 39 million people are blind worldwide, with an estimated 285 million visually impaired. The developing world shoulders 90% of the world's blindness, with 80% of causative diseases being preventable or treatable. Blindness has a major detrimental impact on the patient, community, and healthcare spending. Corneal diseases are significant causes of blindness, affecting at least 4 million people worldwide. The prevalence of corneal disease varies between parts of the world. Trachoma, for instance, is the second leading cause of blindness in Africa, after cataracts, but is rarely found today in developed nations. When preventive strategies have failed, corneal transplantation is the most effective treatment for advanced corneal disease. The major surgical techniques for corneal transplantation include penetrating keratoplasty (PK), anterior lamellar keratoplasty, and endothelial keratoplasty (EK). Indications for corneal transplantation vary between countries, with Fuchs' dystrophy being the leading indication in the USA and keratoconus in Australia. With the exception of the USA, where EK will soon overtake PK as the most common surgical procedure, PK is the overwhelming procedure of choice. Success using corneal grafts in developing nations, such as Nepal, demonstrates the feasibility of corneal transplantation on a global scale. The number of suitable corneas from deceased human donors that becomes available will never be sufficient, and so research into various alternatives, for example stem cells, amniotic membrane transplantation, synthetic and biosynthetic corneas, and xenotransplantation, is progressing. While each of these has potential, we suggest that xenotransplantation holds the greatest potential for a corneal replacement. With the increasing availability of genetically engineered pigs, pig corneas may alleviate the global shortage of corneas in the near future.

  10. The willed blindness of humans

    DEFF Research Database (Denmark)

    Gjerris, Mickey

    2012-01-01

    This paper describes how we seem to live in a willed blindness towards the effects that our meat production and consumption have on animals, the environment and the climate. It is a willed blindness that cannot be explained by either lack of knowledge or scientific uncertainty. The blindness...

  11. Blind compressive sensing dynamic MRI.

    Science.gov (United States)

    Lingala, Sajan Goud; Jacob, Mathews

    2013-06-01

    We propose a novel blind compressive sensing (BCS) frame work to recover dynamic magnetic resonance images from undersampled measurements. This scheme models the dynamic signal as a sparse linear combination of temporal basis functions, chosen from a large dictionary. In contrast to classical compressed sensing, the BCS scheme simultaneously estimates the dictionary and the sparse coefficients from the undersampled measurements. Apart from the sparsity of the coefficients, the key difference of the BCS scheme with current low rank methods is the nonorthogonal nature of the dictionary basis functions. Since the number of degrees-of-freedom of the BCS model is smaller than that of the low-rank methods, it provides improved reconstructions at high acceleration rates. We formulate the reconstruction as a constrained optimization problem; the objective function is the linear combination of a data consistency term and sparsity promoting l1 prior of the coefficients. The Frobenius norm dictionary constraint is used to avoid scale ambiguity. We introduce a simple and efficient majorize-minimize algorithm, which decouples the original criterion into three simpler subproblems. An alternating minimization strategy is used, where we cycle through the minimization of three simpler problems. This algorithm is seen to be considerably faster than approaches that alternates between sparse coding and dictionary estimation, as well as the extension of K-SVD dictionary learning scheme. The use of the l1 penalty and Frobenius norm dictionary constraint enables the attenuation of insignificant basis functions compared to the l0 norm and column norm constraint assumed in most dictionary learning algorithms; this is especially important since the number of basis functions that can be reliably estimated is restricted by the available measurements. We also observe that the proposed scheme is more robust to local minima compared to K-SVD method, which relies on greedy sparse coding. Our

  12. Ligament reconstruction.

    Science.gov (United States)

    Glickel, Steven Z; Gupta, Salil

    2006-05-01

    Volar ligament reconstruction is an effective technique for treating symptomatic laxity of the CMC joint of the thumb. The laxity may bea manifestation of generalized ligament laxity,post-traumatic, or metabolic (Ehler-Danlos). There construction reduces the shear forces on the joint that contribute to the development and persistence of inflammation. Although there have been only a few reports of the results of volar ligament reconstruction, the use of the procedure to treat Stage I and Stage II disease gives good to excellent results consistently. More advanced stages of disease are best treated by trapeziectomy, with or without ligament reconstruction.

  13. [The blindness in the literature-Jose Saramago: blindness and Albert Bang: the blind witness].

    Science.gov (United States)

    Permin, H; Norn, M

    2001-01-01

    Two novels with different aspects of blindness seen through the doctors eyes. The Portuguese Nobel-prize winner José Saramago's story of a city struck by an epidemic of "white blindness", where the truth is what we cannot bear to see. The Danish author and unskilled labourer Albert Bang's (synonym with Karl E. Rasmussen) crime novel describes a blind or pretend to be blind butcher, who is a witness to a murder. Both novels are lyric, thought-provoking and insightful.

  14. [Aiming for zero blindness].

    Science.gov (United States)

    Nakazawa, Toru

    2015-03-01

    Glaucoma is the leading cause of acquired blindness in Japan. One reason that it often leads to blindness is that it can continue to worsen even after effective medical reduction of intraocular pressure (IOP), the only evidence-based treatment. The limitations of current treatments make it critical to identify IOP-independent factors that can cause glaucoma and develop new drugs to target these factors. This is a challenging task, as the pathology of glaucoma is thought to be very complex, with different combinations of factors underlying its development and progression in different patients. Additionally, there is a deficiency in methods to efficiently perform clinical evaluations and reliably probe the state of the disease over relatively short periods. In addition, newly developed drugs need to be evaluated with clinical trials, for which human and financial resources are limited, before they can be widely used for treatment. Taking all these issues into consideration, it is evident that there are two urgent issues to consider: the development of methods to classify glaucoma in detail based on its pathology, and the improvement of clinical evaluation methods. In this review, we discuss some of our efforts to develop new neuroprotective agents for glaucoma, with a focus on the following three areas: 1. Clinical research and development of methods to classify glaucoma in detail based on IOP-independent factors, and the exploration of possibilities for the improvement of clinical evaluation of glaucoma. 2. Pathology-based research and development of new drugs for glaucoma, focusing on comprehensive gene expression analysis and the development of molecule-targeting drugs, using murine optic nerve crush as a disease model. 3. Development of next generation in vivo imaging modalities and the establishment of infrastructure enabling "big-data" analysis. First, we discuss our clinical research and the development of methods to classify glaucoma in detail based on IOP

  15. Climate Reconstructions

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Paleoclimatology Program archives reconstructions of past climatic conditions derived from paleoclimate proxies, in addition to the Program's large holdings...

  16. Breast Reconstruction

    Science.gov (United States)

    ... senos Preguntas Para el Médico Datos Para la Vida Komen El cuidado de sus senos:Consejos útiles ... that can help . Federal law requires most insurance plans cover the cost of breast reconstruction. Learn more ...

  17. Space-Varying Iterative Restoration of Diffuse Optical Tomograms Reconstructed by the Photon Average Trajectories Method

    Directory of Open Access Journals (Sweden)

    Vladimir V. Lyubimov

    2007-01-01

    Full Text Available The possibility of improving the spatial resolution of diffuse optical tomograms reconstructed by the photon average trajectories (PAT method is substantiated. The PAT method recently presented by us is based on a concept of an average statistical trajectory for transfer of light energy, the photon average trajectory (PAT. The inverse problem of diffuse optical tomography is reduced to a solution of an integral equation with integration along a conditional PAT. As a result, the conventional algorithms of projection computed tomography can be used for fast reconstruction of diffuse optical images. The shortcoming of the PAT method is that it reconstructs the images blurred due to averaging over spatial distributions of photons which form the signal measured by the receiver. To improve the resolution, we apply a spatially variant blur model based on an interpolation of the spatially invariant point spread functions simulated for the different small subregions of the image domain. Two iterative algorithms for solving a system of linear algebraic equations, the conjugate gradient algorithm for least squares problem and the modified residual norm steepest descent algorithm, are used for deblurring. It is shown that a 27% gain in spatial resolution can be obtained.

  18. Unconditionally verifiable blind computation

    CERN Document Server

    Fitzsimons, Joseph F

    2012-01-01

    Blind Quantum Computing (BQC) allows a client to have a server carry out a quantum computation for them such that the client's input, output and computation remain private. Recently the authors together with Broadbent proposed a universal unconditionally secure BQC scheme where the client only needs to be able to prepare single qubits in separable states randomly chosen from a finite set and send them to the server, who has the balance of the required quantum computational resources. A desirable property for any BQC protocol is verification, whereby the client can verify with high probability whether the server has followed the instructions of the protocol, or if there has been some deviation resulting in a corrupted output state. A verifiable BQC protocol can be viewed as an interactive proof system leading to consequences for complexity theory. In this paper we extend the BQC protocol presented in [Broadbent, Fitzsimons and Kashefi, FOCS 2009 p517] with new functionality allowing blind computational basis m...

  19. Blind Quantum Computation

    CERN Document Server

    Arrighi, P; Arrighi, Pablo; Salvail, Louis

    2003-01-01

    We investigate the possibility of having someone carry out the work of executing a function for you, but without letting him learn anything about your input. Say Alice wants Bob to compute some well-known function f upon her input x, but wants to prevent Bob from learning anything about x. The situation arises for instance if client Alice has limited computational resources in comparison with mistrusted server Bob, or if x is an inherently mobile piece of data. Could there be a protocol whereby Bob is forced to compute f(x) "blindly", i.e. without observing x? We provide such a blind computation protocol for the class of functions which admit an efficient procedure to generate random input-output pairs, e.g. factorization. The setting is quantum, the security is unconditional, the eavesdropper is as malicious as can be. Keywords: Secure Circuit Evaluation, Secure Two-party Computation, Information Hiding, Information gain vs disturbance.

  20. Color Blind Affirmative Action

    OpenAIRE

    2003-01-01

    This paper presents a conceptual framework for understanding the consequences of the widespread adoption of race-neutral alternatives' to conventional racial affirmative action policies in college admissions. A simple model of applicant competition with endogenous effort is utilized to show that, in comparison to color-conscious affirmative action, these color-blind alternatives can significantly lower the efficiency of the student selection process in equilibrium. We examine data on matricul...

  1. Postpartum cortical blindness.

    Science.gov (United States)

    Faiz, Shakeel Ahmed

    2008-09-01

    A 30-years-old third gravida with previous normal pregnancies and an unremarkable prenatal course had an emergency lower segment caesarean section at a periphery hospital for failure of labour to progress. She developed bilateral cortical blindness immediately after recovery from anesthesia due to cerebral angiopathy shown by CT and MR scan as cortical infarct cerebral angiopathy, which is a rare complication of a normal pregnancy.

  2. Blind Deconvolution for Ultrasound Sequences Using a Noninverse Greedy Algorithm

    Directory of Open Access Journals (Sweden)

    Liviu-Teodor Chira

    2013-01-01

    Full Text Available The blind deconvolution of ultrasound sequences in medical ultrasound technique is still a major problem despite the efforts made. This paper presents a blind noninverse deconvolution algorithm to eliminate the blurring effect, using the envelope of the acquired radio-frequency sequences and a priori Laplacian distribution for deconvolved signal. The algorithm is executed in two steps. Firstly, the point spread function is automatically estimated from the measured data. Secondly, the data are reconstructed in a nonblind way using proposed algorithm. The algorithm is a nonlinear blind deconvolution which works as a greedy algorithm. The results on simulated signals and real images are compared with different state of the art methods deconvolution. Our method shows good results for scatters detection, speckle noise suppression, and execution time.

  3. Nonlinear Reconstruction

    CERN Document Server

    Zhu, Hong-Ming; Pen, Ue-Li; Chen, Xuelei; Yu, Hao-Ran

    2016-01-01

    We present a direct approach to non-parametrically reconstruct the linear density field from an observed non-linear map. We solve for the unique displacement potential consistent with the non-linear density and positive definite coordinate transformation using a multigrid algorithm. We show that we recover the linear initial conditions up to $k\\sim 1\\ h/\\mathrm{Mpc}$ with minimal computational cost. This reconstruction approach generalizes the linear displacement theory to fully non-linear fields, potentially substantially expanding the BAO and RSD information content of dense large scale structure surveys, including for example SDSS main sample and 21cm intensity mapping.

  4. Fighting blindness with microelectronics.

    Science.gov (United States)

    Zrenner, Eberhart

    2013-11-06

    There is no approved cure for blindness caused by degeneration of the photoreceptor cells of the retina. However, there has been encouraging progress with attempts to restore vision using microelectronic retinal implant devices. Yet many questions remain to be addressed. Where is the best location to implant multielectrode arrays? How can spatial and temporal resolution be improved? What are the best ways to ensure the safety and longevity of these devices? Will color vision be possible? This Perspective discusses the current state of the art of retinal implants and attempts to address some of the outstanding questions.

  5. 基于Rudin-Osher-Fatemi模型的图像除模糊和除噪音新模型%A Model for Image Deblurring and Denoising Based on the Rudin-Osher-Fatemi Model

    Institute of Scientific and Technical Information of China (English)

    石玉英; 常谦顺

    2006-01-01

    介绍一种依赖时间的新模型来解决图像除噪音和除模糊问题.分别使用逆反射、中值两种边界条件的数值试验比较本文新模型和Rudin-Osher-Fatemi模型.试验结果表明中值边界条件的误差比逆反射边界条件误差小.%A time dependent model for deblurring and denoising problems is proposed. Comparisons with the Rudin-Osher Fatemi model are made in numerical experiments with antireflective boundary conditions and medium boundary conditions. The results demonstrate that the error with medium boundary conditions is smaller than that with antireflective boundary conditions.

  6. Blind Compressed Sensing Parameter Estimation of Non-cooperative Frequency Hopping Signal

    Directory of Open Access Journals (Sweden)

    Chen Ying

    2016-10-01

    Full Text Available To overcome the disadvantages of a non-cooperative frequency hopping communication system, such as a high sampling rate and inadequate prior information, parameter estimation based on Blind Compressed Sensing (BCS is proposed. The signal is precisely reconstructed by the alternating iteration of sparse coding and basis updating, and the hopping frequencies are directly estimated based on the results. Compared with conventional compressive sensing, blind compressed sensing does not require prior information of the frequency hopping signals; hence, it offers an effective solution to the inadequate prior information problem. In the proposed method, the signal is first modeled and then reconstructed by Orthonormal Block Diagonal Blind Compressed Sensing (OBD-BCS, and the hopping frequencies and hop period are finally estimated. The simulation results suggest that the proposed method can reconstruct and estimate the parameters of noncooperative frequency hopping signals with a low signal-to-noise ratio.

  7. Deaf, blind or deaf-blind: Is touch enhanced?

    Science.gov (United States)

    Papagno, Costanza; Cecchetto, Carlo; Pisoni, Alberto; Bolognini, Nadia

    2016-02-01

    When someone looses one type of sensory input, s/he may compensate by using the sensory information conveyed by other senses. To verify whether loosing a sense or two has consequences on a spared sensory modality, namely touch, and whether these consequences depend on the type of sensory loss, we investigated the effects of deafness and blindness on temporal and spatial tactile tasks in deaf, blind and deaf-blind people. Deaf and deaf-blind people performed the spatial tactile task better than the temporal one, while blind and controls showed the opposite pattern. Deaf and deaf-blind participants were impaired in temporal discrimination as compared to controls, while deaf-blind individuals outperformed blind participants in the spatial tactile task. Overall, sensory-deprived participants did not show an enhanced tactile performance. We speculate that discriminative touch is not so relevant in humans, while social touch is. Probably, more complex tactile tasks would have revealed an increased performance in sensory-deprived people.

  8. ACL reconstruction - discharge

    Science.gov (United States)

    Anterior cruciate ligament reconstruction - discharge; ACL reconstruction - discharge ... had surgery to reconstruct your anterior cruciate ligament (ACL). The surgeon drilled holes in the bones of ...

  9. POSTERIOR SEGMENT CAUSES OF BLINDNESS AMONG CHILDREN IN BLIND SCHOOLS

    Directory of Open Access Journals (Sweden)

    Sandhya

    2015-09-01

    Full Text Available BACKGROUND: It is estimated that there are 1.4 million irreversibly blind children in the world out of which 1 million are in Asia alone. India has the highest number of blind children than any other country. Nearly 70% of the childhood blindness is avoidable. There i s paucity of data available on the causes of childhood blindness. This study focuses on the posterior segment causes of blindness among children attending blind schools in 3 adjacent districts of Andhra Pradesh. MATERIAL & METHODS: This is a cross sectiona l study conducted among 204 blind children aged 6 - 16 years age. Detailed eye examination was done by the same investigator to avoid bias. Posterior segment examination was done using a direct and/or indirect ophthalmoscope after dilating pupil wherever nec essary. The standard WHO/PBL for blindness and low vision examination protocol was used to categorize the causes of blindness. A major anatomical site and underlying cause was selected for each child. The study was carried out during July 2014 to June 2015 . The results were analyzed using MS excel software and Epi - info 7 software version statistical software. RESULTS: Majority of the children was found to be aged 13 - 16 years (45.1% and males (63.7%. Family history of blindness was noted in 26.0% and consa nguinity was reported in 29.9% cases. A majority of them were belonged to fulfill WHO grade of blindness (73.0% and in majority of the cases, the onset of blindness was since birth (83.7%. The etiology of blindness was unknown in majority of cases (57.4% while hereditary causes constituted 25.4% cases. Posterior segment causes were responsible in 33.3% cases with retina being the most commonly involved anatomical site (19.1% followed by optic nerve (14.2%. CONCLUSIONS: There is a need for mandatory oph thalmic evaluation, refraction and assessment of low vision prior to admission into blind schools with periodic evaluation every 2 - 3 years

  10. A fast method for video deblurring based on a combination of gradient methods and denoising algorithms in Matlab and C environments

    Science.gov (United States)

    Mirzadeh, Zeynab; Mehri, Razieh; Rabbani, Hossein

    2010-01-01

    In this paper the degraded video with blur and noise is enhanced by using an algorithm based on an iterative procedure. In this algorithm at first we estimate the clean data and blur function using Newton optimization method and then the estimation procedure is improved using appropriate denoising methods. These noise reduction techniques are based on local statistics of clean data and blur function. For estimated blur function we use LPA-ICI (local polynomial approximation - intersection of confidence intervals) method that use an anisotropic window around each point and obtain the enhanced data employing Wiener filter in this local window. Similarly, to improvement the quality of estimated clean video, at first we transform the data to wavelet transform domain and then improve our estimation using maximum a posterior (MAP) estimator and local Laplace prior. This procedure (initial estimation and improvement of estimation by denoising) is iterated and finally the clean video is obtained. The implementation of this algorithm is slow in MATLAB1 environment and so it is not suitable for online applications. However, MATLAB has the capability of running functions written in C. The files which hold the source for these functions are called MEX-Files. The MEX functions allow system-specific APIs to be called to extend MATLAB's abilities. So, in this paper to speed up our algorithm, the written code in MATLAB is sectioned and the elapsed time for each section is measured and slow sections (that use 60% of complete running time) are selected. Then these slow sections are translated to C++ and linked to MATLAB. In fact, the high loads of information in images and processed data in the "for" loops of relevant code, makes MATLAB an unsuitable candidate for writing such programs. The written code for our video deblurring algorithm in MATLAB contains eight "for" loops. These eighth "for" utilize 60% of the total execution time of the entire program and so the runtime should be

  11. Blind estimation of shallow water acoustic channel

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper proposed a method for blind estimation of underwater channels in shallow water environment by using received data at a single hydrophone or from single beam.First, the received signal is used for source signal reconstruction by means of signal-dependent TF (Time-Frequency) distribution, in association with instantaneous frequency estimation and TF inversion. Then the shallow-water channel estimation is achieved via WRELAX technique by use of the received signal and the estimated source signal. Finally, the results of numerical simulation and experimental test from real data taken in South China Sea trial have proved satisfactory. It is shown that the proposed method is useful for underwater channel estimation.

  12. Deep Blind Compressed Sensing

    OpenAIRE

    Singh, Shikha; Singhal, Vanika; Majumdar, Angshul

    2016-01-01

    This work addresses the problem of extracting deeply learned features directly from compressive measurements. There has been no work in this area. Existing deep learning tools only give good results when applied on the full signal, that too usually after preprocessing. These techniques require the signal to be reconstructed first. In this work we show that by learning directly from the compressed domain, considerably better results can be obtained. This work extends the recently proposed fram...

  13. Overview on Deaf-Blindness

    Science.gov (United States)

    ... build relationships and become the eventual basis for language learning. As the child who is deaf-blind becomes ... those near them, deaf-blindness fosters opportunities for learning and mutual ... M. (Eds.), (1993). Second edition. A model service delivery system for persons ...

  14. National Center On Deaf-Blindness

    Science.gov (United States)

    ... My Profile Logout Menu NCDB: National Center on Deaf-Blindness NCDB: National Center on Deaf-Blindness Help ... Collaborate Project Staff Service Provider Family Member State Deaf-Blind Projects Click on a state on the ...

  15. Breast Reconstruction Alternatives

    Science.gov (United States)

    ... Breast Reconstruction Surgery Breast Cancer Breast Reconstruction Surgery Breast Reconstruction Alternatives Some women who have had a ... chest. What if I choose not to get breast reconstruction? Some women decide not to have any ...

  16. Blind Cognitive MAC Protocols

    CERN Document Server

    Mehanna, Omar; Gamal, Hesham El

    2008-01-01

    We consider the design of cognitive Medium Access Control (MAC) protocols enabling an unlicensed (secondary) transmitter-receiver pair to communicate over the idle periods of a set of licensed channels, i.e., the primary network. The objective is to maximize data throughput while maintaining the synchronization between secondary users and avoiding interference with licensed (primary) users. No statistical information about the primary traffic is assumed to be available a-priori to the secondary user. We investigate two distinct sensing scenarios. In the first, the secondary transmitter is capable of sensing all the primary channels, whereas it senses one channel only in the second scenario. In both cases, we propose MAC protocols that efficiently learn the statistics of the primary traffic online. Our simulation results demonstrate that the proposed blind protocols asymptotically achieve the throughput obtained when prior knowledge of primary traffic statistics is available.

  17. Smooth Reconstruction

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Eighty percent of the reconstruction projects in Sichuan Province will be completed by the end of the year Despite ruins still seen everywhere in the earthquake-hit areas in Sichuan (Province, new buildings have been completed, and many people have moved into new houses. Through cameras of the media, the faces, once painful and melancholy after last year’s earthquake, now look confident and firm, gratifying people all over the

  18. Maxillary reconstruction

    Directory of Open Access Journals (Sweden)

    Brown James

    2007-12-01

    Full Text Available This article aims to discuss the various defects that occur with maxillectomy with a full review of the literature and discussion of the advantages and disadvantages of the various techniques described. Reconstruction of the maxilla can be relatively simple for the standard low maxillectomy that does not involve the orbital floor (Class 2. In this situation the structure of the face is less damaged and the there are multiple reconstructive options for the restoration of the maxilla and dental alveolus. If the maxillectomy includes the orbit (Class 4 then problems involving the eye (enopthalmos, orbital dystopia, ectropion and diplopia are avoided which simplifies the reconstruction. Most controversy is associated with the maxillectomy that involves the orbital floor and dental alveolus (Class 3. A case is made for the use of the iliac crest with internal oblique as an ideal option but there are other methods, which may provide a similar result. A multidisciplinary approach to these patients is emphasised which should include a prosthodontist with a special expertise for these defects.

  19. Corneal blindness: prevention, treatment and rehabilitation

    Directory of Open Access Journals (Sweden)

    Matthew J Burton

    2009-12-01

    Full Text Available Blindness from corneal disease is a major ophthalmic public health problem. There are three important elements to addressing corneal blindness: prevention, treatment, and rehabilitation.

  20. Joint reconstruction strategy for structured illumination microscopy with unknown illuminations

    CERN Document Server

    Labouesse, Simon; Idier, Jérôme; Bourguignon, Sébastien; Negash, Awoke; Liu, Penghuan; Sentenac, Anne

    2016-01-01

    The blind structured illumination microscopy (SIM) strategy proposed in (Mudry et al., 1992) is drastically revisited in this paper, unveiling the mechanism that drives the super-resolution in the method. A much improved numerical implementation is also provided for the reconstruction problem under the image positivity constraint. This algorithm rests on a new preconditioned proximal iteration faster than existing solutions, paving the way to 3D and real-time 2D reconstruction.

  1. Afghanistan Reconstruction

    Institute of Scientific and Technical Information of China (English)

    Fu Xiaoqiang

    2006-01-01

    @@ The Karzai regime has made some progress over the past four years and a half in the post-war reconstruction.However, Taliban's destruction and drug economy are still having serious impacts on the security and stability of Afghanistan.Hence the settlement of the two problems has become a crux of affecting the country' s future.Moreover, the Karzai regime is yet to handle a series of hot potatoes in the fields of central government' s authority, military and police building-up and foreign relations as well.

  2. Perceptual Repetition Blindness Effects

    Science.gov (United States)

    Hochhaus, Larry; Johnston, James C.; Null, Cynthia H. (Technical Monitor)

    1994-01-01

    The phenomenon of repetition blindness (RB) may reveal a new limitation on human perceptual processing. Recently, however, researchers have attributed RB to post-perceptual processes such as memory retrieval and/or reporting biases. The standard rapid serial visual presentation (RSVP) paradigm used in most RB studies is, indeed, open to such objections. Here we investigate RB using a "single-frame" paradigm introduced by Johnston and Hale (1984) in which memory demands are minimal. Subjects made only a single judgement about whether one masked target word was the same or different than a post-target probe. Confidence ratings permitted use of signal detection methods to assess sensitivity and bias effects. In the critical condition for RB a precue of the post-target word was provided prior to the target stimulus (identity precue), so that the required judgement amounted to whether the target did or did not repeat the precue word. In control treatments, the precue was either an unrelated word or a dummy.

  3. LOVE IS COLOR BLIND

    Institute of Scientific and Technical Information of China (English)

    陈梦扬

    2013-01-01

    <正>看完这部电影,突然想起小时候看完《辛德勒的名单》后,问过母亲一个问题:"为什么有些人要嘲笑和歧视那些与众不同的人?"母亲告诉我:"我们都是一样的,没有人应当受到责备,每个人都应当为自己而活,要始终坚信‘Love is color blind(爱无定界)’。"爱究竟有无定界?有太多故事让我们相信这句话并非纸上谈兵。《汤姆叔叔的小屋》、《美国往事》、《为黛西小姐开车》……是的,"Love"是"Listen(倾听)",是无条件无偏见地倾听对方的需求,并予以协助;是"Obligate(感恩)",需要不断地感恩,付出爱来灌

  4. Blinded trials taken to the test

    DEFF Research Database (Denmark)

    Hróbjartsson, A; Forfang, E; Haahr, M T

    2007-01-01

    Blinding can reduce bias in randomized clinical trials, but blinding procedures may be unsuccessful. Our aim was to assess how often randomized clinical trials test the success of blinding, the methods involved and how often blinding is reported as being successful....

  5. What It's Like to Be Color Blind

    Science.gov (United States)

    ... los dientes Video: Getting an X-ray What It's Like to Be Color Blind KidsHealth > For Kids > What It's Like to Be Color Blind Print A A ... blind. But some people really are color blind. It doesn't mean they can't see any ...

  6. Blindness in children: a worldwide perspective

    Directory of Open Access Journals (Sweden)

    Clare Gilber

    2007-06-01

    Full Text Available Many of the causes of childhood blindness are avoidable, being either preventable or treatable. Only three per cent of the world's blind population are children. However, because children have a lifetime of blindness ahead of them, the number of ‘blind person years’ resulting from blindness starting in childhood is second only to cataract. Controlling blindness in children is a priority of VISION 20203,4; however, as its causes differ from that of blindness in adults, different strategies, personnel, infrastructure, and equipment are required to combat it. There is also a greater urgency when managing children, as delays in treatment can lead to amblyopia (lazy eye.

  7. Reconstructive Urology

    Directory of Open Access Journals (Sweden)

    Fikret Fatih Önol

    2014-11-01

    Full Text Available In the treatment of urethral stricture, Buccal Mucosa Graft (BMG and reconstruction is applied with different patch techniques. Recently often prefered, this approach is, in bulber urethra strictures of BMG’s; by “ventral onley”, in pendulous urethra because of thinner spingiosis body, which provides support and nutrition of graft; by means of “dorsal inley” being anastomosis. In the research that Cordon et al. did, they compared conventional BMJ “onley” urethroplast and “pseudo-spongioplasty” which base on periurethral vascular tissues to be nourished by closing onto graft. In repairment of front urethras that spongiosis supportive tissue is insufficient, this method is defined as peripheral dartos [çevre dartos?] and buck’s fascia being mobilized and being combined on BMG patch. Between the years 2007 and 2012, assessment of 56 patients with conventional “ventral onley” BMG urethroplast and 46 patients with “pseudo-spongioplasty” were reported to have similar success rates (80% to 84% in 3.5 year follow-up on average. While 74% of the patients that were applied pseudo-spongioplasty had disease present at distal urethra (pendulous, bulbopendulous, 82% of the patients which were applied conventional onley urethroplast had stricture at proximal (bulber urethra yet. Also lenght of the stricture at the pseudo-spongioplasty group was longer in a statistically significant way (5.8 cm to 4.7 cm on average, p=0.028. This study which Cordon et al. did, shows that conditions in which conventional sponjiyoplasti is not possible, periurethral vascular tissues are adequate to nourish BMG. Even it is an important technique in terms of bringing a new point of view to today’s practice, data especially about complications that may show up after pseudo-spongioplasty usage on long distal strictures (e.g. appearance of urethral diverticulum is not reported. Along with this we think that, providing an oppurtinity to patch directly

  8. Access to Mathematics by Blind Students: A Global Problem

    OpenAIRE

    Karshmer, Arthur I.; Daryoush D. Farsi

    2007-01-01

    The issue of blindness and legally blind is becoming a global issue. Based on the last statistics from American Foundation for the blind, there are approximately 10 million blind and visually impaired people in the United States alone. Over 45 million people around the world are completely blind. 180 million more people are legally blind, and approximately 7 million people are diagnosed as blind or legally blind every year. One of the greatest stumbling blocks in the ability of the blind to e...

  9. A Combined First and Second Order Variational Approach for Image Reconstruction

    KAUST Repository

    Papafitsoros, K.

    2013-05-10

    In this paper we study a variational problem in the space of functions of bounded Hessian. Our model constitutes a straightforward higher-order extension of the well known ROF functional (total variation minimisation) to which we add a non-smooth second order regulariser. It combines convex functions of the total variation and the total variation of the first derivatives. In what follows, we prove existence and uniqueness of minimisers of the combined model and present the numerical solution of the corresponding discretised problem by employing the split Bregman method. The paper is furnished with applications of our model to image denoising, deblurring as well as image inpainting. The obtained numerical results are compared with results obtained from total generalised variation (TGV), infimal convolution and Euler\\'s elastica, three other state of the art higher-order models. The numerical discussion confirms that the proposed higher-order model competes with models of its kind in avoiding the creation of undesirable artifacts and blocky-like structures in the reconstructed images-a known disadvantage of the ROF model-while being simple and efficiently numerically solvable. ©Springer Science+Business Media New York 2013.

  10. New treatments of hereditary blindness

    DEFF Research Database (Denmark)

    Bertelsen, Mette; Rosenberg, Thomas; Larsen, Michael

    2013-01-01

    Ongoing clinical trials are targeting several previously intractable hereditary causes of blindness of congenital, childhood or early adulthood onset, mainly in the optic nerve and retina. The intended stage of initiation of the new therapeutic approaches ranges from neonatal life and a structura......Ongoing clinical trials are targeting several previously intractable hereditary causes of blindness of congenital, childhood or early adulthood onset, mainly in the optic nerve and retina. The intended stage of initiation of the new therapeutic approaches ranges from neonatal life...... and a structurally intact retinal tissue to adult life with a complete loss of photoreceptors. It must be assumed that some of the trials will succeed in producing new therapies and action must be taken to refine and accelerate diagnostics and to preserve therapeutic potential in blind people....

  11. A model of blind zone for in situ monitoring the solid/liquid interface using ultrasonic wave.

    Science.gov (United States)

    Peng, Song; Ouyang, Qi; Zhu, Z Z; Zhang, X L

    2015-07-01

    To in situ monitor a solid/liquid interface to control metal qualities, the paper analysis blind models of the ultrasonic propagation in the solidifying molten metal with a solid/liquid interface in the Bridgman type furnace, and a mathematical calculation model of blind zone with different source locations and surface concavities is built. The study points out that the blind zone I is caused by ray bending in the interface edge, and the blind zone II is caused by totally reflection which is related with initial ray angle, critical refraction angle of solid/liquid media. A serial of simulation experiments are operated on the base of the model, and numerical computation results coincide with model calculated results very well. Therefore, receiver should locate beyond these blind zones in the right boundary to obtain time of flight data which is used to reconstruct the solid/liquid interface.

  12. Night blindness and ancient remedy

    Directory of Open Access Journals (Sweden)

    H.A. Hajar Al Binali

    2014-01-01

    Full Text Available The aim of this article is to briefly review the history of night blindness and its treatment from ancient times until the present. The old Egyptians, the Babylonians, the Greeks and the Arabs used animal liver for treatment and successfully cured the disease. The author had the opportunity to observe the application of the old remedy to a patient. Now we know what the ancients did not know, that night blindness is caused by Vitamin A deficiency and the animal liver is the store house for Vitamin A.

  13. Resolving intravoxel fiber architecture using nonconvex regularized blind compressed sensing

    Science.gov (United States)

    Chu, C. Y.; Huang, J. P.; Sun, C. Y.; Liu, W. Y.; Zhu, Y. M.

    2015-03-01

    In diffusion magnetic resonance imaging, accurate and reliable estimation of intravoxel fiber architectures is a major prerequisite for tractography algorithms or any other derived statistical analysis. Several methods have been proposed that estimate intravoxel fiber architectures using low angular resolution acquisitions owing to their shorter acquisition time and relatively low b-values. But these methods are highly sensitive to noise. In this work, we propose a nonconvex regularized blind compressed sensing approach to estimate intravoxel fiber architectures in low angular resolution acquisitions. The method models diffusion-weighted (DW) signals as a sparse linear combination of unfixed reconstruction basis functions and introduces a nonconvex regularizer to enhance the noise immunity. We present a general solving framework to simultaneously estimate the sparse coefficients and the reconstruction basis. Experiments on synthetic, phantom, and real human brain DW images demonstrate the superiority of the proposed approach.

  14. Exploration Flight Test 1 Afterbody Aerothermal Environment Reconstruction

    Science.gov (United States)

    Hyatt, Andrew J.; Oliver, Brandon; Amar, Adam; Lessard, Victor

    2016-01-01

    The Exploration Flight Test 1 vehicle included roughly 100 near surface thermocouples on the after body of the vehicle. The temperature traces at each of these instruments have been used to perform inverse environment reconstruction to determine the aerothermal environment experienced during re-entry of the vehicle. This paper provides an overview of the reconstructed environments and identifies critical aspects of the environment. These critical aspects include transition and reaction control system jet influence. A blind test of the process and reconstruction tool was also performed to build confidence in the reconstructed environments. Finally, an uncertainty quantification analysis was also performed to identify the impact of each of the uncertainties on the reconstructed environments.

  15. From Shell Shock to Shellac: The Great War, Blindness, and Britain's Talking Book Library.

    Science.gov (United States)

    Rubery, Matthew

    2015-01-01

    Britain's Talking Book Service began as a way of providing reading material to soldiers blinded during the First World War. This account traces the talking book's development from the initial experiments after the War to its debut and reception among blind soldiers and civilians in the 1930s. It has been put together using archives held by the Royal National Institute of Blind People (before its Royal Charter, the NIB) and Blind Veterans UK (formerly St. Dunstan's), the two organizations responsible for Britain's Talking Book Service. The essay's first section reconstructs the search for an alternative way of reading that would benefit people with vision impairments. The next part demonstrates the talking book's impact on the lives of people with disabilities, recovering the voices of blind readers left out of most histories of books, literacy, and reading practices in the twentieth century. The final section reconstructs a debate over the value of recorded books, showing that disputes over their legitimacy are as old as recorded books themselves. In sum, this essay confronts the central issue raised by the convergence of books, media, and disability in the War's aftermath: can a book talk?

  16. Elliptic Curve Blind Digital Signature Schemes

    Institute of Scientific and Technical Information of China (English)

    YOULin; YANGYixian; WENQiaoyan

    2003-01-01

    Blind signature schemes are important cryptographic protocols in guaranteeing the privacy or anonymity of the users.Three new blind signature schemes and their corresponding generalizations are pro-posed. Moreover, their securities are simply analyzed.

  17. The Concept and Operations of Blind Number

    Institute of Scientific and Technical Information of China (English)

    PANG Yan-jun; LIU Kai-di; ZHANG Bo-wen

    2001-01-01

    This paper gives the definition and operations of blind number, and discusses its operationproperties. Blind number is a mathematical tool to express and deal with complex information with severalkinds of uncertainty.

  18. Blinding in randomized clinical trials: imposed impartiality

    DEFF Research Database (Denmark)

    Hróbjartsson, A; Boutron, I

    2011-01-01

    Blinding, or "masking," is a crucial method for reducing bias in randomized clinical trials. In this paper, we review important methodological aspects of blinding, emphasizing terminology, reporting, bias mechanisms, empirical evidence, and the risk of unblinding. Theoretical considerations...

  19. American Foundation for the Blind

    Science.gov (United States)

    ... News Research Navigator: A Series on Research in Blindness and Visual Impairment Stay Involved Enter your e-mail address to receive AFB eNews: Helen Keller A Driving Force Behind AFB Learn more about Helen Keller Visit the Helen Keller Kids Museum Directory of Services Find Local Services: Select a ...

  20. Convolutive Blind Source Separation Methods

    DEFF Research Database (Denmark)

    Pedersen, Michael Syskind; Larsen, Jan; Kjems, Ulrik

    2008-01-01

    During the past decades, much attention has been given to the separation of mixed sources, in particular for the blind case where both the sources and the mixing process are unknown and only recordings of the mixtures are available. In several situations it is desirable to recover all sources fro...

  1. The Blind as "Ordinary People".

    Science.gov (United States)

    Feinman, Saul

    1978-01-01

    Based on a paper presented at the 1977 Western Social Science Association Meeting in Denver, Colorado, the article reports on a study that compared major demographic features of a sample of 70 legally blind adults with the sighted adult sample studied in the 1975 National Opinion Research Center General Social Survey. (Author/DLS)

  2. The Blind Learning Aptitude Test.

    Science.gov (United States)

    Newland, T. Ernest

    A Blind Learning Aptitude Test (BLAT) was developed on the basis of sense of touch rather than on conventional experience, fine sensory discrimination, or verbal competency. From a pool of about 350 items, most of them used in testing intelligence in the sighted, a pool of 94 was selected and embossed after the manner of braille. A residual pool…

  3. Partially Blind Signatures Based on Quantum Cryptography

    Science.gov (United States)

    Cai, Xiao-Qiu; Niu, Hui-Fang

    2012-12-01

    In a partially blind signature scheme, the signer explicitly includes pre-agreed common information in the blind signature, which can improve the availability and performance. We present a new partially blind signature scheme based on fundamental properties of quantum mechanics. In addition, we analyze the security of this scheme, and show it is not possible to forge valid partially blind signatures. Moreover, the comparisons between this scheme and those based on public-key cryptography are also discussed.

  4. Tactile maze solving in congenitally blind individuals

    DEFF Research Database (Denmark)

    Gagnon, Léa; Kupers, Ron; Schneider, Fabien C;

    2010-01-01

    Vision is undoubtedly important for navigation although not essential as blind individuals outperform their blindfolded seeing counterparts in a variety of navigational tasks. It is believed that the blind's superior performance is because of their efficient use of proprioceptive signals and envi......Vision is undoubtedly important for navigation although not essential as blind individuals outperform their blindfolded seeing counterparts in a variety of navigational tasks. It is believed that the blind's superior performance is because of their efficient use of proprioceptive signals...

  5. Poverty and blindness in Africa.

    Science.gov (United States)

    Naidoo, Kovin

    2007-11-01

    Africa carries a disproportionate responsibility in terms of blindness and visual impairment. With approximately 10 per cent of the world's population, Africa has 19 per cent of the world's blindness. It is no surprise that this reality also mirrors the situation in terms of the burden of world poverty. There is an increasing recognition of the need to highlight the link between poverty, development and health care. Blindness, disabling visual impairment and the overall lack of eye-care services are too often the result of social, economic and developmental challenges of the developing world. The state of eye care in Africa stands in alarming contrast to that in the rest of the world. Poor practitioner-to-patient ratios, absence of eye-care personnel, inadequate facilities, poor state funding and a lack of educational programs are the hallmarks of eye care in Africa, with preventable and treatable conditions being the leading cause of blindness. Eye diseases causing preventable blindness are often the result of a combination of factors such as poverty, lack of education and inadequate health-care services. The challenge that Vision 2020 has set itself in Africa is enormous. Africa is not a homogenous entity, the inter- and intra-country differences in economic development, prevalence of disease, delivery infrastructure and human resources amplify the challenges of meeting eye-care needs. The successful implementation of Vision 2020 programs will be hindered without the development of a comprehensive, co-ordinated strategy that is cognisant of the differences that exist and the need for comprehensive solutions that are rooted in the economic and political realities of the continent as well as the individual countries and regions within countries. This strategy should recognise the need for economic growth that results in greater state funded eye-care services that focus on health promotion to ensure the prevention of eye disease, the development of eye clinics in

  6. Occupant satisfaction with two blind control strategies

    DEFF Research Database (Denmark)

    Karlsen, Line Røseth; Heiselberg, Per Kvols; Bryn, Ida

    2015-01-01

    Highlights •Occupant satisfaction with two blind control strategies has been studied. •Control based on cut-off position of slats was more popular than closed slats. •Results from the study are helpful in development of control strategies for blinds. •The results give indications of how blinds...

  7. BLIND ADAPTIVE XPIC BASED ON HOS

    Institute of Scientific and Technical Information of China (English)

    Fu Haiyang; Yang Longxiang; Peng Jianglong

    2001-01-01

    This paper presents a new blind XPIC and a new adaptive blind deconvolutional algorithm based on HOS processing, which separates and equalizes the signals in real time. The simulation results demonstrate that the performance of the proposed adaptive blind algorithm,compared with the conventional algorithms, is outstanding with the feature of feasibility, stability and fast convergence rate.

  8. Psychomotor Development for the Deaf-Blind.

    Science.gov (United States)

    Sherrill, Claudine

    The stages of psychomotor development in deaf blind children and youth are reviewed, and educational principles to guide psychomotor development programs for the deaf blind are outlined. Etiological factors which contribute to the psychomotor development of deaf blind persons are discussed including nonambulation and sensory deprivation, heart…

  9. From" Televised Blind Date” to" Televised Half-blind Wedding”

    Institute of Scientific and Technical Information of China (English)

    倪俊

    2001-01-01

    @@ A couple of weeks ago I happened to see on TV how American young men and women go out on "blind dates” , arranged by a television station. It is interesting to see how a young man and a young woman enjoy playing, dining or chatting with each other happily and naturally before a TV camera, even though they have never known or met with each other before. Yesterday evening one of the biggest national TV stations, FOX by name, made another bold try by broadcasting live a "half-blind wedding” to the whole country. It is such an original and also absurd idea that 1 think only American television-men can have figured it out and carried it out.

  10. From "Televised Blind Date" to "Televised Half-blind Wedding"

    Institute of Scientific and Technical Information of China (English)

    倪俊

    2001-01-01

    A couple of weeks ago I happened to see on TV how American young men and women go out on "blind dates", arranged by a television station, It is interesting to see bow a young man and a young woman enjoy playing, dining or chatting with each other happily and naturally before a TV camera, even though they have never known or met with each other before. Yesterday evening one of the biggest national TV stations, FOX by name, made another bold try by broadcasting live a "half-blind wedding" to the whole country. It is such an original and also absurd idea that I think only American television-men can have figured it out and carried it out. In the beginning, the directors of FOX put ads in newspapers, openly asking the public: "Who wants to marry a multi-millionaire?" It did not cost much time or

  11. Neuromagnetic source reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, P.S.; Mosher, J.C. [Los Alamos National Lab., NM (United States); Leahy, R.M. [University of Southern California, Los Angeles, CA (United States)

    1994-12-31

    In neuromagnetic source reconstruction, a functional map of neural activity is constructed from noninvasive magnetoencephalographic (MEG) measurements. The overall reconstruction problem is under-determined, so some form of source modeling must be applied. We review the two main classes of reconstruction techniques-parametric current dipole models and nonparametric distributed source reconstructions. Current dipole reconstructions use a physically plausible source model, but are limited to cases in which the neural currents are expected to be highly sparse and localized. Distributed source reconstructions can be applied to a wider variety of cases, but must incorporate an implicit source, model in order to arrive at a single reconstruction. We examine distributed source reconstruction in a Bayesian framework to highlight the implicit nonphysical Gaussian assumptions of minimum norm based reconstruction algorithms. We conclude with a brief discussion of alternative non-Gaussian approachs.

  12. Color blindness and Rorschach color responsivity.

    Science.gov (United States)

    Corsino, B V

    1985-10-01

    Color vision deficits occur in 10% of the American white male population. Thus, color blindness may invalidate diagnostic hypotheses generated from Rorschach data. The Rorschach protocols of 43 white, college male color-blind subjects were compared to the protocols of normally sighted controls. The color-blind group manifested fewer pure "C" responses. No significant between group differences emerged for any of the other primary Rorschach color variables. Pure "C" responses rarely figure prominently in Rorschach evaluations, and the apparent lowered frequency of these responses by the color-blind is insufficient to warrant modification of current Rorschach practice. The data suggest that color blindness is unlikely to confound Rorschach assessment.

  13. BLIND SERBIAN RULERS AND FAMOUS PERSONS

    Directory of Open Access Journals (Sweden)

    Janicijevic Katarina

    2016-12-01

    Full Text Available History and medicine were an integral part of life-being of blind serbian acters. One of the main actors was half-blind serbian ruler, Stefan of Decani and whose name was associated with first ophthalmologic hospital and precursor of the eye`s injuries care. After, national reputation as Stefan Blind Righteous, ruler of the Serbian despot between 1458. and 1459. (member of Brankovic`s dinasty, and he was blinded by eye injuries burns. The famous national was also Filip Visnjic, as blind minstrel and authentic creator of serbian folk traditions, with sequels as a child, by bilateral infective panuveitis.

  14. [Cortical plasticity in blind individual].

    Science.gov (United States)

    Wang, Shu-zhen; Zhu, Si-quan

    2008-10-01

    The cognitive mechanisms and functional brain imaging research on blind individuals provide special information for exploring the plasticity of the developing human brain. This paper focuses on five aspects of recent progress in this field: (1) the behavior compensation of the blind; (2) the influence of early visual deprivation and later visual deprivation on cross-modal reorganization; (3) the relationship between the complexity of task requirement and cross-modal reorganization; (4) the relationship between the sensitive periods of the visual system and the time course of cross-modal reorganization; (5) the neural mechanisms of cross-modal reorganization. These findings contribute greatly to the theoretical basis of the rehabilitation of individuals with perceptual deficits.

  15. Demonstration of blind quantum computing.

    Science.gov (United States)

    Barz, Stefanie; Kashefi, Elham; Broadbent, Anne; Fitzsimons, Joseph F; Zeilinger, Anton; Walther, Philip

    2012-01-20

    Quantum computers, besides offering substantial computational speedups, are also expected to preserve the privacy of a computation. We present an experimental demonstration of blind quantum computing in which the input, computation, and output all remain unknown to the computer. We exploit the conceptual framework of measurement-based quantum computation that enables a client to delegate a computation to a quantum server. Various blind delegated computations, including one- and two-qubit gates and the Deutsch and Grover quantum algorithms, are demonstrated. The client only needs to be able to prepare and transmit individual photonic qubits. Our demonstration is crucial for unconditionally secure quantum cloud computing and might become a key ingredient for real-life applications, especially when considering the challenges of making powerful quantum computers widely available.

  16. [Double-blind peer review].

    Science.gov (United States)

    Fenyvesi, Tamás

    2002-02-03

    The peer review process in medical sciences is much debated. The method is not yet evidence based. Who are the reviewers and how do they perform? They are "independent" experts. As such they are bound to be involved in research similar to that outlined in the manuscript. Very often they are contestant in the same race. That is why the author consider the double blind method, where the author is blinded and the reviewer masked from each other's identity, the best choice. Nevertheless in very many scientific journals of high quality and envied impact factors do not blind the identity of the authors. Science is a race for fame, self accomplishment and also a means to get grants for pursuing the scientific research. Only success is able to provide resources for expensive scientific research. There is no fail-safe method against bias in grant giving and editorial process. In the tidal wave of electronic information it is mandatory to help in differentiating between signal and noise in science. Peer review is the best method to protect readers from the trash of uncontrolled publications in medical science.

  17. Breast reconstruction after mastectomy

    Directory of Open Access Journals (Sweden)

    Daniel eSchmauss

    2016-01-01

    Full Text Available Breast cancer is the leading cause of cancer death in women worldwide. Its surgical approach has become less and less mutilating in the last decades. However, the overall number of breast reconstructions has significantly increased lately. Nowadays breast reconstruction should be individualized at its best, first of all taking into consideration oncological aspects of the tumor, neo-/adjuvant treatment and genetic predisposition, but also its timing (immediate versus delayed breast reconstruction, as well as the patient’s condition and wish. This article gives an overview over the various possibilities of breast reconstruction, including implant- and expander-based reconstruction, flap-based reconstruction (vascularized autologous tissue, the combination of implant and flap, reconstruction using non-vascularized autologous fat, as well as refinement surgery after breast reconstruction.

  18. Reoperative midface reconstruction.

    Science.gov (United States)

    Acero, Julio; García, Eloy

    2011-02-01

    Reoperative reconstruction of the midface is a challenging issue because of the complexity of this region and the severity of the aesthetic and functional sequela related to the absence or failure of a primary reconstruction. The different situations that can lead to the indication of a reoperative reconstructive procedure after previous oncologic ablative procedures in the midface are reviewed. Surgical techniques, anatomic problems, and limitations affecting the reoperative reconstruction in this region of the head and neck are discussed.

  19. Surfaces, Digitisations and Reconstructions

    DEFF Research Database (Denmark)

    2015-01-01

    We present a new digital reconstruction of r-regular sets in three-dimensional Euclidean space. We introduce a vector field and analyse the relation between the topologies of the boundaries of the r-regular set and its reconstruction. This reconstruction can be carried out faster than prior models...

  20. Should I Have Breast Reconstruction?

    Science.gov (United States)

    ... Reconstruction Surgery Breast Cancer Breast Reconstruction Surgery Should I Get Breast Reconstruction Surgery? Women who have surgery ... It usually responds well to treatment. What if I choose not to have breast reconstruction? Many women ...

  1. Corneal reconstruction by stem cells and bioengineering

    Directory of Open Access Journals (Sweden)

    Arjamaa O

    2012-09-01

    Full Text Available Olli ArjamaaDepartment of Biology, University of Turku, Turku, FinlandAbstract: Almost 300 million people are visually impaired worldwide due to various eye diseases such as cataracts, glaucoma, age-related macular degeneration, diabetic retinopathy, and corneal diseases. Notably, ten million people are blind because of severe ocular surface diseases and the majority of cases occur in developing countries. Blinding ocular surface diseases have, however, become treatable by grafting of surface layers, or by full-thickness transplantation of the cornea. As the demand for human corneal tissue for surface reconstruction and transplantation far exceeds the supply, methods are being developed to supplement tissue donation. Xenotransplantation of the cornea or cells from genetically modified pigs may become one of the solutions. Transplantation of limbal stem cells within tissue biopsies, to restore the transparency of the cornea is another remarkable method, which has shown its potential in several clinical studies. The combination of stem cell technology and engineering of biocompatible tissue equivalent, still at preclinical stage, has shown us how synthetic corneal tissue is able to guide cultured corneal stromal stem cells of human origin, to become native-like stroma, the most important layer of the cornea. These findings give hope for a large-quantity production of biomaterial for corneal reconstruction. As such, clinical ophthalmologists should become more familiar with the methods of laboratory science.Keywords: eye, grafting, keratoplasty, xenotransplantation, cell reservoir, biocompatible tissue equivalent

  2. Provably secure robust threshold partial blind signature

    Institute of Scientific and Technical Information of China (English)

    CAO Zhenfu; ZHU Haojin; LU Rongxing

    2006-01-01

    Threshold digital signature and blind signature are playing important roles in cryptography as well as in practical applications such as e-cash and e-voting systems.Over the past few years, many cryptographic researchers have made considerable headway in this field. However, to our knowledge, most of existing threshold blind signature schemes are based on the discrete logarithm problem. In this paper, we propose a new robust threshold partial blind signature scheme based on improved RSA cryptosystem.This scheme is the first threshold partial blind signature scheme based on factoring, and the robustness of threshold partial blind signature is also introduced. Moreover, in practical application, the proposed scheme will be especially suitable for blind signature-based voting systems with multiple administrators and secure electronic cash systems to prevent their abuse.

  3. Reduced taste sensitivity in congenital blindness

    DEFF Research Database (Denmark)

    Gagnon, Lea; Kupers, Ron; Ptito, Maurice

    2013-01-01

    thresholds of the 5 basic tastants in 13 congenitally blind and 13 sighted control subjects. Participants also answered several eating habits questionnaires, including the Food Neophobia Scale, the Food Variety Seeking Tendency Scale, the Intuitive Eating Scale, and the Body Awareness Questionnaire. Our...... behavioral results showed that compared with the normal sighted, blind subjects have increased thresholds for taste detection and taste identification. This finding is at odds with the superior performance of congenitally blind subjects in several tactile, auditory and olfactory tasks. Our psychometric data...... further indicate that blind subjects more strongly rely on internal hunger and satiety cues, instead of external contextual or emotional cues, to decide when and what to eat. We suggest that the lower taste sensitivity observed in congenitally blind individuals is due to various blindness...

  4. Blindness

    Science.gov (United States)

    ... good vision would be able to read certain letters from 20 feet (6 meters) away. Eyesight this good is called 20/20 vision, although some people can see even better than that. The numbers change depending on ...

  5. [Breast reconstruction after mastectomy].

    Science.gov (United States)

    Ho Quoc, C; Delay, E

    2013-02-01

    The mutilating surgery for breast cancer causes deep somatic and psychological sequelae. Breast reconstruction can mitigate these effects and permit the patient to help rebuild their lives. The purpose of this paper is to focus on breast reconstruction techniques and on factors involved in breast reconstruction. The methods of breast reconstruction are presented: objectives, indications, different techniques, operative risks, and long-term monitoring. Many different techniques can now allow breast reconstruction in most patients. Clinical cases are also presented in order to understand the results we expect from a breast reconstruction. Breast reconstruction provides many benefits for patients in terms of rehabilitation, wellness, and quality of life. In our mind, breast reconstruction should be considered more as an opportunity and a positive choice (the patient can decide to do it), than as an obligation (that the patient would suffer). The consultation with the surgeon who will perform the reconstruction is an important step to give all necessary informations. It is really important that the patient could speak again with him before undergoing reconstruction, if she has any doubt. The quality of information given by medical doctors is essential to the success of psychological intervention. This article was written in a simple, and understandable way to help gynecologists giving the best information to their patients. It is maybe also possible to let them a copy of this article, which would enable them to have a written support and would facilitate future consultation with the surgeon who will perform the reconstruction.

  6. A Rare Hydrocephalus Complication: Cortical Blindness.

    Science.gov (United States)

    Ünal, Emre; Göçmen, Rahşan; Işıkay, Ayşe İlksen; Tekşam, Özlem

    2015-01-01

    Cortical blindness related to bilateral occipital lobe infarction is an extremely rare complication of hydrocephalus. Compression of the posterior cerebral artery, secondary to tentorial herniation, is the cause of occipital infarction. Particularly in children and mentally ill patients, cortical blindness may be missed. Therefore, early diagnosis and treatment of hydrocephalus is important. We present herein a child of ventricular shunt malfunction complicated by cortical blindness.

  7. CERTIFICATELESS SIGNATURE AND BLIND SIGNATURE

    Institute of Scientific and Technical Information of China (English)

    Zhang Lei; Zhang Futai

    2008-01-01

    Certificateless public key cryptography is a new paradigm introduced by AI-Riyami and Paterson. It eliminates the need of the certificates in traditional public key cryptosystems and the key escrow problem in IDentity-based Public Key Cryptography (ID-PKC). Due to the advantages of the certificateless public key cryptography,a new efficient certificateless pairing-based signature scheme is presented,which has some advantages over previous constructions in computational cost. Based on this new signature scheme,a certificateless blind signature scheme is proposed. The security of our schemes is proven based on the hardness of computational Diffie-Hellman problem.

  8. Causes of blindness and needs of the blind in Mansoura, Egypt.

    Science.gov (United States)

    el-Gilany, A H; el-Fedawy, S; Tharwat, M

    2002-01-01

    A study of 113 blind people in Mansoura, Egypt highlighted the causes and risk factors for blindness, and health and social care needs of the blind. In two-thirds of cases, blindness occurred before 10 years of age. Risk factors for blindness were reported by more than half the study population. Congenital causes accounted for almost half the cases. The commonest causes of bilateral blindness were corneal opacities, cataract and glaucoma. Almost three-quarters of causes were avoidable. Health and social care for this group was inadequate and more than half would benefit from further management. Legislation for keratoplasty, a registry of blind people, and a nationwide community survey on the epidemiology of blindness are needed urgently.

  9. Blindness and Insight in King Lear

    Institute of Scientific and Technical Information of China (English)

    岳元玉

    2008-01-01

    This paper intends to explore how William Shakespeare illustrates the theme of blindness and insight in his great tragedy "King Lear".Four characters’ deeds and their fate are used as a case study to examine what blindness is,what insight is,and the relationship between the two.The writer finds that by depicting the characters’ deeds and their fate in a double plot,Shakespeare renders the folly of blindness,the transition from blindness to insight,and the use of reason and thought to understand the truth.

  10. Congenital color blindness in young Turkish men.

    Science.gov (United States)

    Citirik, Mehmet; Acaroglu, Golge; Batman, Cosar; Zilelioglu, Orhan

    2005-04-01

    We investigated a healthy population of men from different regions of Turkey for the presence of congenital red-green color blindness. Using Ishihara pseudoisochromatic plates, 941 healthy men from the Turkish army were tested for congenital red-green color blindness. The prevalence of red-green color blindness was 7.33 +/- 0.98% (5.10% protans and 2.23% deutans). These ratios were higher than other reported samples from Mediterranean Europe. Higher percentages of color blindness were found in regions with a lower education level and more consanguineous marriages.

  11. Comparison of Training, Blind and Semi Blind Equalizers in MIMO Fading Systems Using Capacity as Measure

    OpenAIRE

    Kavitha, Veeraruna; Sharma, Vinod

    2005-01-01

    Semi blind/blind equalizers are believed to work unsatisfactorily in fading MIMO channels compared to training based methods, due to slow convergence or high computational complexity. We revisit this issue. Defining a 'composite' channel for each equalizer, we compare the three algorithms based on the capacity of this channel. We show that, in a Rician (with line of sight, LOS) environment, semi blind/blind algorithms outperform training equalizers, but in Rayleigh channels, it is better to u...

  12. 75 FR 47304 - Accessible Mobile Phone Options for People Who Are Blind, Deaf-Blind, or Have Low Vision

    Science.gov (United States)

    2010-08-05

    ... COMMISSION Accessible Mobile Phone Options for People Who Are Blind, Deaf- Blind, or Have Low Vision AGENCY... accessible for people who are blind, have vision loss, or are deaf-blind and the extent to which gaps in... deaf-blind; recommendations on the most effective and efficient technical policy solutions...

  13. Blind Source Separation with Compressively Sensed Linear Mixtures

    CERN Document Server

    Kleinsteuber, Martin

    2011-01-01

    This work studies the problem of simultaneously separating and reconstructing signals from compressively sensed linear mixtures. We assume that all source signals share a common sparse representation basis. The approach combines classical Compressive Sensing (CS) theory with a linear mixing model. It allows the mixtures to be sampled independently of each other. If samples are acquired in the time domain, this means that the sensors need not be synchronized. Since Blind Source Separation (BSS) from a linear mixture is only possible up to permutation and scaling, factoring out these ambiguities leads to a minimization problem on the so-called oblique manifold. We develop a geometric conjugate subgradient method that scales to large systems for solving the problem. Numerical results demonstrate the promising performance of the proposed algorithm compared to several state of the art methods.

  14. Sweep Distortion Removal from THz Images via Blind Demodulation

    CERN Document Server

    Aghasi, Alireza; Redo-Sanchez, Albert; Romberg, Justin; Raskar, Ramesh

    2016-01-01

    Heavy sweep distortion induced by alignments and inter-reflections of layers of a sample is a major burden in recovering 2D and 3D information in time resolved spectral imaging. This problem cannot be addressed by conventional denoising and signal processing techniques as it heavily depends on the physics of the acquisition. Here we propose and implement an algorithmic framework based on low-rank matrix recovery and alternating minimization that exploits the forward model for THz acquisition. The method allows recovering the original signal in spite of the presence of temporal-spatial distortions. We address a blind-demodulation problem, where based on several observations of the sample texture modulated by an undesired sweep pattern, the two classes of signals are separated. The performance of the method is examined in both synthetic and experimental data, and the successful reconstructions are demonstrated. The proposed general scheme can be implemented to advance inspection and imaging applications in THz ...

  15. Cosmic Tidal Reconstruction

    CERN Document Server

    Zhu, Hong-Ming; Yu, Yu; Er, Xinzhong; Chen, Xuelei

    2015-01-01

    The gravitational coupling of a long wavelength tidal field with small scale density fluctuations leads to anisotropic distortions of the locally measured small scale matter correlation function. Since the local correlation function is statistically isotropic in the absence of such tidal interactions, the tidal distortions can be used to reconstruct the long wavelength tidal field and large scale density field in analogy with the cosmic microwave background lensing reconstruction. In this paper we present in detail a formalism for the cosmic tidal reconstruction and test the reconstruction in numerical simulations. We find that the density field on large scales can be reconstructed with good accuracy and the cross correlation coefficient between the reconstructed density field and the original density field is greater than 0.9 on large scales ($k\\lesssim0.1h/\\mathrm{Mpc}$). This is useful in the 21cm intensity mapping survey, where the long wavelength radial modes are lost due to foreground subtraction proces...

  16. Front blind spot crashes in Hong Kong.

    Science.gov (United States)

    Cheng, Yuk Ki; Wong, Koon Hung; Tao, Chi Hang; Tam, Cheok Ning; Tam, Yiu Yan; Tsang, Cheuk Nam

    2016-09-01

    In 2012-2014, our laboratory had investigated a total of 9 suspected front blind spot crashes, in which the medium and heavy goods vehicles pulled away from rest and rolled over the pedestrians, who were crossing immediately in front of the vehicles. The drivers alleged that they did not see any pedestrians through the windscreens or the front blind spot mirrors. Forensic assessment of the goods vehicles revealed the existence of front blind spot zones in 3 out of these 9 accident vehicles, which were attributed to the poor mirror adjustments or even the absence of a front blind spot mirror altogether. In view of this, a small survey was devised involving 20 randomly selected volunteers and their goods vehicles and 5 out of these vehicles had blind spots at the front. Additionally, a short questionnaire was conducted on these 20 professional lorry drivers and it was shown that most of them were not aware of the hazards of blind spots immediately in front of their vehicles, and many did not use the front blind spot mirrors properly. A simple procedure for quick measurements of the coverage of front blind spot mirrors using a coloured plastic mat with dimensional grids was also introduced and described in this paper.

  17. Blavigator: a navigation aid for blind persons

    OpenAIRE

    José,João; Moreno, M.; Pinilla-Dutoit, J.; Rodrigues, J. M. F.; du Buf, J. M. H.

    2012-01-01

    Blavigator (blind navigator) is a vision aid for blind and visuaIIy impaired persons. It supports local navigation by detecting waIkable paths in the immediate vicinity of the user. It guides the user for centering on the path.

  18. Blind Equalization Based on Evolution Strategies

    Institute of Scientific and Technical Information of China (English)

    SongYu; ZhangXianda; 等

    1997-01-01

    Conventional blind equalization algorithms suffer from ill convergence to local minima and slow convergence speed.This paper proposes a novel blind equalization algorithm.using random search methods-evolution strategies and existing cost functions,Simulation results verify the fast and global convergence of the proposed algorithm.

  19. Ptychographic ultrafast pulse reconstruction

    CERN Document Server

    Spangenberg, D; Brügmann, M H; Feurer, T

    2014-01-01

    We demonstrate a new ultrafast pulse reconstruction modality which is somewhat reminiscent of frequency resolved optical gating but uses a modified setup and a conceptually different reconstruction algorithm that is derived from ptychography. Even though it is a second order correlation scheme it shows no time ambiguity. Moreover, the number of spectra to record is considerably smaller than in most other related schemes which, together with a robust algorithm, leads to extremely fast convergence of the reconstruction.

  20. Early Interactions with Children Who Are Deaf-Blind

    Science.gov (United States)

    ... Logout Menu Early Interactions With Children Who Are Deaf-Blind NCDB: National Center on Deaf-Blindness Help ... Archived Webinars Early Interactions With Children Who Are Deaf-Blind by DB-LINK on Apr 1, 2008 ...

  1. Blind separation of incoherent and spatially disjoint sound sources

    Science.gov (United States)

    Dong, Bin; Antoni, Jérôme; Pereira, Antonio; Kellermann, Walter

    2016-11-01

    Blind separation of sound sources aims at reconstructing the individual sources which contribute to the overall radiation of an acoustical field. The challenge is to reach this goal using distant measurements when all sources are operating concurrently. The working assumption is usually that the sources of interest are incoherent - i.e. statistically orthogonal - so that their separation can be approached by decorrelating a set of simultaneous measurements, which amounts to diagonalizing the cross-spectral matrix. Principal Component Analysis (PCA) is traditionally used to this end. This paper reports two new findings in this context. First, a sufficient condition is established under which "virtual" sources returned by PCA coincide with true sources; it stipulates that the sources of interest should be not only incoherent but also spatially orthogonal. A particular case of this instance is met by spatially disjoint sources - i.e. with non-overlapping support sets. Second, based on this finding, a criterion that enforces both statistical and spatial orthogonality is proposed to blindly separate incoherent sound sources which radiate from disjoint domains. This criterion can be easily incorporated into acoustic imaging algorithms such as beamforming or acoustical holography to identify sound sources of different origins. The proposed methodology is validated on laboratory experiments. In particular, the separation of aeroacoustic sources is demonstrated in a wind tunnel.

  2. Altered sleep-wake patterns in blindness

    DEFF Research Database (Denmark)

    Aubin, S.; Gacon, C.; Jennum, P.

    2016-01-01

    discuss variability in the sleep–wake pattern between blind and normal-sighted individuals. Methods Thirty-day actigraphy recordings were collected from 11 blind individuals without residual light perception and 11 age- and sex-matched normal-sighted controls. From these recordings, we extracted...... episode in blind participants as compared to sighted control participants. We also confirm previous reports of reduced sleep quality in blind individuals. Notably, the variability in sleep efficiency and in the timing of sleep correlated with the severity of sleep disturbances. Conclusion The timing...... and physiology of sleep are strongly dependent on the endogenous circadian phase; therefore, observed findings support the hypothesis of free-running circadian rhythms as a dominant factor for the sleep disturbances experienced in blindness....

  3. An ECC-Based Blind Signature Scheme

    Directory of Open Access Journals (Sweden)

    Fuh-Gwo Jeng

    2010-08-01

    Full Text Available Cryptography is increasingly applied to the E-commerce world, especially to the untraceable payment system and the electronic voting system. Protocols for these systems strongly require the anonymous digital signature property, and thus a blind signature strategy is the answer to it. Chaum stated that every blind signature protocol should hold two fundamental properties, blindness and intractableness. All blind signature schemes proposed previously almost are based on the integer factorization problems, discrete logarithm problems, or the quadratic residues, which are shown by Lee et al. that none of the schemes is able to meet the two fundamental properties above. Therefore, an ECC-based blind signature scheme that possesses both the above properties is proposed in this paper.

  4. User-centered Technologies For Blind Children

    Directory of Open Access Journals (Sweden)

    Jaime Sánchez

    2008-01-01

    Full Text Available The purpose of this paper is to review, summarize, and illustrate research work involving four audio-based games created within a user-centered design methodology through successive usability tasks and evaluations. These games were designed by considering the mental model of blind children and their styles of interaction to perceive and process data and information. The goal of these games was to enhance the cognitive development of spatial structures, memory, haptic perception, mathematical skills, navigation and orientation, and problem solving of blind children. Findings indicate significant improvements in learning and cognition from using audio-based tools specially tailored for the blind. That is, technologies for blind children, carefully tailored through user-centered design approaches, can make a significant contribution to cognitive development of these children. This paper contributes new insight into the design and implementation of audio-based virtual environments to facilitate learning and cognition in blind children.

  5. Blind Braille readers mislocate tactile stimuli.

    Science.gov (United States)

    Sterr, Annette; Green, Lisa; Elbert, Thomas

    2003-05-01

    In a previous experiment, we observed that blind Braille readers produce errors when asked to identify on which finger of one hand a light tactile stimulus had occurred. With the present study, we aimed to specify the characteristics of this perceptual error in blind and sighted participants. The experiment confirmed that blind Braille readers mislocalised tactile stimuli more often than sighted controls, and that the localisation errors occurred significantly more often at the right reading hand than at the non-reading hand. Most importantly, we discovered that the reading fingers showed the smallest error frequency, but the highest rate of stimulus attribution. The dissociation of perceiving and locating tactile stimuli in the blind suggests altered tactile information processing. Neuroplasticity, changes in tactile attention mechanisms as well as the idea that blind persons may employ different strategies for tactile exploration and object localisation are discussed as possible explanations for the results obtained.

  6. BLIND DIFFERENTIAL ADAPTIVE MULTIUSER DETECTION

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper, a new blind equalization cost function, termed differential mean output energy (DMOE), was presented, and a new multiuser detection algorithm with variable step size was designed. It is shown through simulation results for a co-channel system involving severe MAI that the DMOE algorithm gives significantly enhanced signal to interference ratio (SIR) performance and converges rapidly to the optimum MMSE detector, together with a low computational complexity requirement relative to the recursive least squares (RLS) algorithm. Thus, it is not necessary to switch to the decision-directed mode. Moreover, it also exhibits global convergence, and can be used in different interference environment without the requirement of estimating and restricting the surplus energy.

  7. Blind-date Conversation Joining

    Directory of Open Access Journals (Sweden)

    Luca Cesari

    2013-07-01

    Full Text Available We focus on a form of joining conversations among multiple parties in service-oriented applications where a client may asynchronously join an existing conversation without need to know in advance any information about it. More specifically, we show how the correlation mechanism provided by orchestration languages enables a form of conversation joining that is completely transparent to clients and that we call 'blind-date joining'. We provide an implementation of this strategy by using the standard orchestration language WS-BPEL. We then present its formal semantics by resorting to COWS, a process calculus specifically designed for modelling service-oriented applications. We illustrate our approach by means of a simple, but realistic, case study from the online games domain.

  8. Parallel hyperspectral image reconstruction using random projections

    Science.gov (United States)

    Sevilla, Jorge; Martín, Gabriel; Nascimento, José M. P.

    2016-10-01

    Spaceborne sensors systems are characterized by scarce onboard computing and storage resources and by communication links with reduced bandwidth. Random projections techniques have been demonstrated as an effective and very light way to reduce the number of measurements in hyperspectral data, thus, the data to be transmitted to the Earth station is reduced. However, the reconstruction of the original data from the random projections may be computationally expensive. SpeCA is a blind hyperspectral reconstruction technique that exploits the fact that hyperspectral vectors often belong to a low dimensional subspace. SpeCA has shown promising results in the task of recovering hyperspectral data from a reduced number of random measurements. In this manuscript we focus on the implementation of the SpeCA algorithm for graphics processing units (GPU) using the compute unified device architecture (CUDA). Experimental results conducted using synthetic and real hyperspectral datasets on the GPU architecture by NVIDIA: GeForce GTX 980, reveal that the use of GPUs can provide real-time reconstruction. The achieved speedup is up to 22 times when compared with the processing time of SpeCA running on one core of the Intel i7-4790K CPU (3.4GHz), with 32 Gbyte memory.

  9. Structured illumination fluorescence microscopy with distorted excitations using a filtered blind-SIM algorithm.

    Science.gov (United States)

    Ayuk, R; Giovannini, H; Jost, A; Mudry, E; Girard, J; Mangeat, T; Sandeau, N; Heintzmann, R; Wicker, K; Belkebir, K; Sentenac, A

    2013-11-15

    Structured illumination microscopy (SIM) is a powerful technique for obtaining super-resolved fluorescence maps of samples, but it is very sensitive to aberrations or misalignments affecting the excitation patterns. Here, we present a reconstruction algorithm that is able to process SIM data even if the illuminations are strongly distorted. The approach is an extension of the recent blind-SIM technique, which reconstructs simultaneously the sample and the excitation patterns without a priori information on the latter. Our algorithm was checked on synthetic and experimental data using distorted and nondistorted illuminations. The reconstructions were similar to that obtained by up-to-date SIM methods when the illuminations were periodic and remained artifact-free when the illuminations were strongly distorted.

  10. Delayed breast implant reconstruction

    DEFF Research Database (Denmark)

    Hvilsom, Gitte B.; Hölmich, Lisbet R.; Steding-Jessen, Marianne;

    2012-01-01

    We evaluated the association between radiation therapy and severe capsular contracture or reoperation after 717 delayed breast implant reconstruction procedures (288 1- and 429 2-stage procedures) identified in the prospective database of the Danish Registry for Plastic Surgery of the Breast during...... reconstruction approaches other than implants should be seriously considered among women who have received radiation therapy....

  11. Internet Adaptation for Colour-Blind Persons

    Directory of Open Access Journals (Sweden)

    Rytė Žiūrienė

    2011-04-01

    Full Text Available Of all human race about 8% of males and 0,5% of females are colour-blind. It is estimated that in 2011 or 2012 there will be around 2 billion Internet users worldwide, so the number of colour-blind Internet users can reach about 200 million. Authors of this publication analyse issues that arise for colour-blind persons on the Internet and deliver the ways to make the Internet more comfortable. The special software is proposed as one of the ways together with comparison of its advantages.

  12. Blind image deconvolution methods and convergence

    CERN Document Server

    Chaudhuri, Subhasis; Rameshan, Renu

    2014-01-01

    Blind deconvolution is a classical image processing problem which has been investigated by a large number of researchers over the last four decades. The purpose of this monograph is not to propose yet another method for blind image restoration. Rather the basic issue of deconvolvability has been explored from a theoretical view point. Some authors claim very good results while quite a few claim that blind restoration does not work. The authors clearly detail when such methods are expected to work and when they will not. In order to avoid the assumptions needed for convergence analysis in the

  13. Ten years left to eliminate blinding trachoma

    Directory of Open Access Journals (Sweden)

    Haddad D.

    2010-09-01

    Full Text Available n 1997, the World Health Organization formed the Global Alliance to Eliminate Blinding Trachoma by 2020 (GET 2020, a coalition of governmental, non-governmental, research, and pharmaceutical partners. In 1998, the World Health Assembly urged member states to map blinding trachoma in endemic areas, implement the SAFE strategy (which stands for surgery for trichiasis, antibiotics, facial-cleanliness and environmental change, such as clean water and latrines and collaborate with the global alliance in its work to eliminate blinding trachoma.

  14. Reversible cortical blindness: posterior reversible encephalopathy syndrome.

    Science.gov (United States)

    Bandyopadhyay, Sabyasachi; Mondal, Kanchan Kumar; Das, Somnath; Gupta, Anindya; Biswas, Jaya; Bhattacharyya, Subir Kumar; Biswas, Gautam

    2010-11-01

    Cortical blindness is defined as visual failure with preserved pupillary reflexes in structurally intact eyes due to bilateral lesions affecting occipital cortex. Bilateral oedema and infarction of the posterior and middle cerebral arterial territory, trauma, glioma and meningioma of the occipital cortex are the main causes of cortical blindness. Posterior reversible encephalopathy syndrome (PRES) refers to the reversible subtype of cortical blindness and is usually associated with hypertension, diabetes, immunosuppression, puerperium with or without eclampsia. Here, 3 cases of PRES with complete or partial visual recovery following treatment in 6-month follow-up are reported.

  15. Blindness of Johann Sebastian Bach.

    Science.gov (United States)

    Tarkkanen, Ahti

    2013-03-01

    Johann Sebastian Bach (1685-1750) was one of the greatest composers of all time. Apart from performing as a brilliant organist, he composed over 1.100 works in almost every musical genre. He was known as a hardworking, deeply Christian person, who had to support his family of 20 children and many students staying at his home. At the age of 64 years, his vision started to decline. Old biographies claim that it was the result of overstressing his vision in poor illumination. By persuasion of his friends, he had his both eyes operated by a travelling British eye surgeon. A cataract couching was performed. After surgery, Bach was totally blind and unable to play an organ, compose or direct choirs and orchestras. He was confined to bed and suffering from immense pain of the eyes and the body. He died <4 months after surgery. In this paper, as the plausible diagnosis, intractable glaucoma because of pupillary block or secondary to phacoanaphylactic endophthalmitis is suggested.

  16. Night blindness and Crohn's disease.

    Science.gov (United States)

    da Rocha Lima, Breno; Pichi, Francesco; Lowder, Careen Y

    2014-10-01

    Signs of malnutrition are common clinical features in Crohn's disease; and bowel resection, commonly needed in these cases, can aggravate malnutrition. These patients are at risk of developing vitamin A deficiency, which can lead to night blindness. We present a 60-year-old male, with history of Crohn's disease and multiple resections for strictures and fistulas leading to short bowel syndrome, with progressive bilateral loss of night vision (nyctalopia). Serum vitamin A level was markedly depleted (11 µg/dL, reference 20-120 µg/dL), and full-field electroretinogram testing demonstrated extinguished scotopic (rod function) responses and decreased amplitudes of photopic responses on 30 Hz flicker (cone function). He was started on vitamin A supplementation (initially intramuscular). His vitamin A level was back to normal (78 µg/dL), and night vision problems subjectively improved. Patients with Crohn's disease should be inquired about night vision problems. The presence of nyctalopia should prompt vitamin A level measurement and ophthalmology referral for further evaluation.

  17. Reconstructing Step by Step

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    On May 22,10 days after the Wenchuan earthquake in Sichuan Province,the State Council formed the Post-earthquake Reconstruction Planning Group,deciding to work out a general recon- struction plan within a period of three months. Sichuan was the worst-hit area of China,so reconstruction work there will have a direct influence on how plans proceed in other areas.On July 18,Beijing Review reporter Feng Jianhua interviewed Wang Guangsi,Vice Director of the Sichuan Development and Reform Commission,about Sichuan’s reconstruction plan.

  18. Imagery limitations in totally congenitally blind subjects.

    Science.gov (United States)

    De Beni, R; Cornoldi, C

    1988-10-01

    Research on totally blind subjects performing tasks that involve visual imagery has often shown that they do not behave differently from matched sighted subjects, even when their blindness is congenital. If visual imagery is based on visual perception, such tasks may not required visual imagery. In the present article visual images are considered as representations maintaining some properties of visible objects and constructed on the basis of information from various sources. Owing to the absence of visual experience, the limitations of such representations are explored in a series of experiments requiring memorization of single nouns, pairs of nouns, or triplets of nouns associated with a cue noun. Recall by blind subjects was impaired when multiple interactive images (with noun pairs and triplets) are formed. The poorer recall of blind subjects reflected also loss of order information. Recall was better for both groups with locative noun cues and high-imagery targets.

  19. Hypertension and color blindness in young men.

    Science.gov (United States)

    Morton, W E

    1975-05-01

    Medical data from Selective Service registrants born from 1939 to 1941 were studied in Oregon and Colorado. Among 29,119 registrants with medical information (41.3% of all registrants), 1,073 (3.6%) had definite hypertension, and 1,226 (4.2%) had some type of color blindness. In both states, there was a highly significant association between the prevalence of hypertension and the prevalence of color blindness. Thus, definite hypertension was present in 6.0% of color clind individuals but in only 3.6% of those with unimparied color vision, while color blindness occurred in 6.8% with definite hypertension, in 5.8% with borderline hypertension, and in only 4.0% with normal blood pressure. The data did not differentiate among types of color blindness, and the reason for the association is not yet evident.

  20. Ask a Scientist: What is Color Blindness?

    Science.gov (United States)

    ... Stuff Cool Eye Tricks Links to More Information Optical Illusions Printables Ask a Scientist Video Series Why can’ ... a scientist? Click to Watch What is an optical illusion? Click to Watch What is color blindness? Click ...

  1. Enhanced heat discrimination in congenital blindness

    DEFF Research Database (Denmark)

    Slimani, Hocine; Ptito, Maurice; Kupers, Ron

    2015-01-01

    There is substantial evidence that congenitally blind individuals perform better than normally sighted controls in a variety of auditory, tactile and olfactory discrimination tasks. However, little is known about the capacity of blind individuals to make fine discriminatory judgments in the thermal...... discrimination. Thermal stimuli were delivered with either a 2.56 or 9 cm(2) Peltier-based thermode. We applied for 5-8s lasting non-painful thermal stimuli to the forearm and asked participants to detect small increments in temperature (ΔT = 0.4, 0.8, 1.2 or 1.6°C) that occurred at random time intervals. Blank...... of the stimulated skin surface or magnitude of the temperature shift. Increasing the size of the stimulated skin area increased the response criterion in the blind (p=0.022) but not in the sighted. Together, these findings show that congenitally blind individuals have enhanced temperature discrimination accuracy...

  2. Transient cortical blindness after coronary angiography.

    Science.gov (United States)

    Alp, B N; Bozbuğa, N; Tuncer, M A; Yakut, C

    2009-01-01

    Transient cortical blindness is rarely encountered after angiography of native coronary arteries or bypass grafts. This paper reports a case of transient cortical blindness that occurred 72 h after coronary angiography in a 56-year old patient. This was the patient's fourth exposure to contrast medium. Neurological examination demonstrated cortical blindness and the absence of any focal neurological deficit. A non-contrast-enhanced computed tomographic scan of the brain revealed bilateral contrast enhancement in the occipital lobes and no evidence of cerebral haemorrhage, and magnetic resonance imaging of the brain showed no pathology. Sight returned spontaneously within 4 days and his vision gradually improved. A search of the current literature for reported cases of transient cortical blindness suggested that this is a rarely encountered complication of coronary angiography.

  3. Reversible cortical blindness after lung transplantation.

    Science.gov (United States)

    Knower, Mark T; Pethke, Scott D; Valentine, Vincent G

    2003-06-01

    Cyclosporine (CYA) is a calcineurin inhibitor widely used in immunosuppressive regimens after organ transplantation. Several neurologic side effects are frequently associated with CYA use; however, reversible cortical blindness is a rare manifestation of CYA toxicity traditionally seen after liver and bone marrow transplantation. This report presents a case of reversible cortical blindness after lung transplantation, then details the risk factors and clinical course of 28 previously well-documented cases of CYA-induced cortical blindness after transplantation. Identification of known risk factors, clinical clues, and typical radiographic findings may aid in the diagnosis of CYA-induced cortical blindness, since reduction in CYA dose or cessation of CYA therapy usually permits resolution of the neurologic effects.

  4. Ask a Scientist: What is Color Blindness?

    Medline Plus

    Full Text Available ... Sheldon Miller answers questions about color blindness, whether it can be treated, and how people become color ... I’m sleeping? Click to Watch What does it mean to be nearsighted or farsighted? Click to ...

  5. From Perception to Metacognition: Auditory and Olfactory Functions in Early Blind, Late Blind, and Sighted Individuals

    Science.gov (United States)

    Cornell Kärnekull, Stina; Arshamian, Artin; Nilsson, Mats E.; Larsson, Maria

    2016-01-01

    Although evidence is mixed, studies have shown that blind individuals perform better than sighted at specific auditory, tactile, and chemosensory tasks. However, few studies have assessed blind and sighted individuals across different sensory modalities in the same study. We tested early blind (n = 15), late blind (n = 15), and sighted (n = 30) participants with analogous olfactory and auditory tests in absolute threshold, discrimination, identification, episodic recognition, and metacognitive ability. Although the multivariate analysis of variance (MANOVA) showed no overall effect of blindness and no interaction with modality, follow-up between-group contrasts indicated a blind-over-sighted advantage in auditory episodic recognition, that was most pronounced in early blind individuals. In contrast to the auditory modality, there was no empirical support for compensatory effects in any of the olfactory tasks. There was no conclusive evidence for group differences in metacognitive ability to predict episodic recognition performance. Taken together, the results showed no evidence of an overall superior performance in blind relative sighted individuals across olfactory and auditory functions, although early blind individuals exceled in episodic auditory recognition memory. This observation may be related to an experience-induced increase in auditory attentional capacity. PMID:27729884

  6. From perception to metacognition: Auditory and olfactory functions in early blind, late blind, and sighted individuals

    Directory of Open Access Journals (Sweden)

    Stina Cornell Kärnekull

    2016-09-01

    Full Text Available Although evidence is mixed, studies have shown that blind individuals perform better than sighted at specific auditory, tactile, and chemosensory tasks. However, few studies have assessed blind and sighted individuals across different sensory modalities in the same study. We tested early blind (n = 15, late blind (n = 15, and sighted (n = 30 participants with analogous olfactory and auditory tests in absolute threshold, discrimination, identification, episodic recognition, and metacognitive ability. Although the multivariate analysis of variance (MANOVA showed no overall effect of blindness and no interaction with modality, follow-up between-group contrasts indicated a blind-over-sighted advantage in auditory episodic recognition, that was most pronounced in early blind individuals. In contrast to the auditory modality, there was no empirical support for compensatory effects in any of the olfactory tasks. There was no conclusive evidence for group differences in metacognitive ability to predict episodic recognition performance. Taken together, the results showed no evidence of an overall superior performance in blind relative sighted individuals across olfactory and auditory functions, although early blind individuals exceled in episodic auditory recognition memory. This observation may be related to an experience-induced increase in auditory attentional capacity.

  7. An Efficient Scheme for Sensitive Message Transmission using Blind Signcryption

    OpenAIRE

    Awasthi, Amit K; Lal, Sunder

    2005-01-01

    Blind signature schemes enable a useful protocol that guarantee the anonymity of the participants while Signcryption offers authentication of message and confidentiality of messages at the same time and more efficiently. In this paper, we present a blind signcryption scheme that combines the functionality of blind signature and signcryption. This blind Signcryption is useful for applications that are based on anonymity untracebility and unlinkability.

  8. Shape Perception and Navigation in Blind Adults

    Science.gov (United States)

    Gori, Monica; Cappagli, Giulia; Baud-Bovy, Gabriel; Finocchietti, Sara

    2017-01-01

    Different sensory systems interact to generate a representation of space and to navigate. Vision plays a critical role in the representation of space development. During navigation, vision is integrated with auditory and mobility cues. In blind individuals, visual experience is not available and navigation therefore lacks this important sensory signal. In blind individuals, compensatory mechanisms can be adopted to improve spatial and navigation skills. On the other hand, the limitations of these compensatory mechanisms are not completely clear. Both enhanced and impaired reliance on auditory cues in blind individuals have been reported. Here, we develop a new paradigm to test both auditory perception and navigation skills in blind and sighted individuals and to investigate the effect that visual experience has on the ability to reproduce simple and complex paths. During the navigation task, early blind, late blind and sighted individuals were required first to listen to an audio shape and then to recognize and reproduce it by walking. After each audio shape was presented, a static sound was played and the participants were asked to reach it. Movements were recorded with a motion tracking system. Our results show three main impairments specific to early blind individuals. The first is the tendency to compress the shapes reproduced during navigation. The second is the difficulty to recognize complex audio stimuli, and finally, the third is the difficulty in reproducing the desired shape: early blind participants occasionally reported perceiving a square but they actually reproduced a circle during the navigation task. We discuss these results in terms of compromised spatial reference frames due to lack of visual input during the early period of development. PMID:28144226

  9. Blind source separation dependent component analysis

    CERN Document Server

    Xiang, Yong; Yang, Zuyuan

    2015-01-01

    This book provides readers a complete and self-contained set of knowledge about dependent source separation, including the latest development in this field. The book gives an overview on blind source separation where three promising blind separation techniques that can tackle mutually correlated sources are presented. The book further focuses on the non-negativity based methods, the time-frequency analysis based methods, and the pre-coding based methods, respectively.

  10. Blind Signature Scheme Based on Chebyshev Polynomials

    OpenAIRE

    Maheswara Rao Valluri

    2011-01-01

    A blind signature scheme is a cryptographic protocol to obtain a valid signature for a message from a signer such that signer’s view of the protocol can’t be linked to the resulting message signature pair. This paper presents blind signature scheme using Chebyshev polynomials. The security of the given scheme depends upon the intractability of the integer factorization problem and discrete logarithms ofChebyshev polynomials.

  11. Blind Signature Scheme Based on Chebyshev Polynomials

    Directory of Open Access Journals (Sweden)

    Maheswara Rao Valluri

    2011-12-01

    Full Text Available A blind signature scheme is a cryptographic protocol to obtain a valid signature for a message from a signer such that signer’s view of the protocol can’t be linked to the resulting message signature pair. This paper presents blind signature scheme using Chebyshev polynomials. The security of the given scheme depends upon the intractability of the integer factorization problem and discrete logarithms ofChebyshev polynomials.

  12. Quantum group blind signature scheme without entanglement

    Science.gov (United States)

    Xu, Rui; Huang, Liusheng; Yang, Wei; He, Libao

    2011-07-01

    In this paper we propose a quantum group blind signature scheme designed for distributed e-voting system. Our scheme combines the properties of group signature and blind signature to provide anonymity of voters in an e-voting system. The unconditional security of our scheme is ensured by quantum mechanics. Without employing entanglement, the proposed scheme is easier to be realized comparing with other quantum signature schemes.

  13. Can acupuncture treatment be double-blinded?

    DEFF Research Database (Denmark)

    Vase, Lene; Baram, Sara; Takakura, Nobuari;

    2015-01-01

    and acupuncturists were asked about perceived treatment allocation at the end of the study. To test if there were clues which led to identification of the treatment, deep dull pain associated with needle application and rotation (termed "de qi" in East Asian medicine), and patients' pain levels were assessed...... is the only needle that allows some degree of practitioner blinding. The study raises questions about alternatives to double-blind randomized clinical trials in the assessment of acupuncture treatment....

  14. Numerical simulation of ventilation in blinding heading

    Institute of Scientific and Technical Information of China (English)

    CHANG De-qiang; LIU Jing-xian; CHEN Bao-zhi

    2008-01-01

    The way of ventilation in all its forms and characteristics in the blinding heading was studied. On the basis of computational fluid dynamics (CFD) the turbulence model of restrained ventilation in blinding heading was set up, and the calculation boundary condi-tions were analyzed. According to the practice application the three-dimensional flow field of ventilation in blinding heading was simulated by the computational fluid dynamics soft-ware. The characteristics of the ventilation flow field such as the temperature field zone and the flow filed zone and the rule of the flow velocity were obtained. The ventilation in blinding heading under certain circumstances was calculated and simulated for optimiza-tion. The optimal ventilation form and related parameters under given condition were ob-tained. The rule of the ventilation in blinding heading was theoretical analyzed, which pro-vided reference for the research on the process of mass transfer, the rule of hazardous substances transportation and ventilation efficiency, provided a new method for the study of reasonable and effective ventilation in blinding heading.

  15. Numerical simulation of ventilation in blinding heading

    Institute of Scientific and Technical Information of China (English)

    CHANG De-qiang; LIU Jing-xian; CHEN Bao-zhi

    2008-01-01

    The way of ventilation in all its forms and characteristics in the blinding heading was studied.On the basis of computational fluid dynamics (CFD) the turbulence model of restrained ventilation in blinding heading was set up,and the calculation boundary conditions were analyzed.According to the practice application the three-dimensional flow field of ventilation in blinding heading was simulated by the computational fluid dynamics software.The characteristics of the ventilation flow field such as the temperature field zone and the flow filed zone and the rule of the flow velocity were obtained.The ventilation in blinding heading under certain circumstances was calculated and simulated for optimization.The optimal ventilation form and related parameters under given condition were obtained.The rule of the ventilation in blinding heading was theoretical analyzed,which provided reference for the research on the process of mass transfer,the rule of hazardous substances transportation and ventilation efficiency,provided a new method for the study of reasonable and effective ventilation in blinding heading.

  16. Unblinding the dark matter blind spots

    Science.gov (United States)

    Han, Tao; Kling, Felix; Su, Shufang; Wu, Yongcheng

    2017-02-01

    The dark matter (DM) blind spots in the Minimal Supersymmetric Standard Model (MSSM) refer to the parameter regions where the couplings of the DM particles to the Z-boson or the Higgs boson are almost zero, leading to vanishingly small signals for the DM direct detections. In this paper, we carry out comprehensive analyses for the DM searches under the blind-spot scenarios in MSSM. Guided by the requirement of acceptable DM relic abundance, we explore the complementary coverage for the theory parameters at the LHC, the projection for the future underground DM direct searches, and the indirect searches from the relic DM annihilation into photons and neutrinos. We find that (i) the spin-independent (SI) blind spots may be rescued by the spin-dependent (SD) direct detection in the future underground experiments, and possibly by the indirect DM detections from IceCube and SuperK neutrino experiments; (ii) the detection of gamma rays from Fermi-LAT may not reach the desirable sensitivity for searching for the DM blind-spot regions; (iii) the SUSY searches at the LHC will substantially extend the discovery region for the blind-spot parameters. The dark matter blind spots thus may be unblinded with the collective efforts in future DM searches.

  17. Prairie Reconstruction Initiative Project

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of the Prairie Reconstruction Initiative Advisory Team (PRIAT) is to identify and take steps to resolve uncertainties in the process of prairie...

  18. On TPC cluster reconstruction

    CERN Document Server

    Dydak, F; Nefedov, Y; Wotschack, J; Zhemchugov, A

    2004-01-01

    For a bias-free momentum measurement of TPC tracks, the correct determination of cluster positions is mandatory. We argue in particular that (i) the reconstruction of the entire longitudinal signal shape in view of longitudinal diffusion, electronic pulse shaping, and track inclination is important both for the polar angle reconstruction and for optimum r phi resolution; and that (ii) self-crosstalk of pad signals calls for special measures for the reconstruction of the z coordinate. The problem of 'shadow clusters' is resolved. Algorithms are presented for accepting clusters as 'good' clusters, and for the reconstruction of the r phi and z cluster coordinates, including provisions for 'bad' pads and pads next to sector boundaries, respectively.

  19. Permutationally invariant state reconstruction

    DEFF Research Database (Denmark)

    Moroder, Tobias; Hyllus, Philipp; Tóth, Géza;

    2012-01-01

    Feasible tomography schemes for large particle numbers must possess, besides an appropriate data acquisition protocol, an efficient way to reconstruct the density operator from the observed finite data set. Since state reconstruction typically requires the solution of a nonlinear large-scale opti......Feasible tomography schemes for large particle numbers must possess, besides an appropriate data acquisition protocol, an efficient way to reconstruct the density operator from the observed finite data set. Since state reconstruction typically requires the solution of a nonlinear large...... likelihood and least squares methods, which are the preferred choices in today's experiments. This high efficiency is achieved by greatly reducing the dimensionality of the problem employing a particular representation of permutationally invariant states known from spin coupling combined with convex...

  20. Permutationally invariant state reconstruction

    CERN Document Server

    Moroder, Tobias; Toth, Geza; Schwemmer, Christian; Niggebaum, Alexander; Gaile, Stefanie; Gühne, Otfried; Weinfurter, Harald

    2012-01-01

    Feasible tomography schemes for large particle numbers must possess, besides an appropriate data acquisition protocol, also an efficient way to reconstruct the density operator from the observed finite data set. Since state reconstruction typically requires the solution of a non-linear large-scale optimization problem, this is a major challenge in the design of scalable tomography schemes. Here we present an efficient state reconstruction scheme for permutationally invariant quantum state tomography. It works for all common state-of-the-art reconstruction principles, including, in particular, maximum likelihood and least squares methods, which are the preferred choices in today's experiments. This high efficiency is achieved by greatly reducing the dimensionality of the problem employing a particular representation of permutationally invariant states known from spin coupling combined with convex optimization, which has clear advantages regarding speed, control and accuracy in comparison to commonly employed n...

  1. Reconstructions of eyelid defects

    Directory of Open Access Journals (Sweden)

    Nirmala Subramanian

    2011-01-01

    Full Text Available Eyelids are the protective mechanism of the eyes. The upper and lower eyelids have been formed for their specific functions by Nature. The eyelid defects are encountered in congenital anomalies, trauma, and postexcision for neoplasm. The reconstructions should be based on both functional and cosmetic aspects. The knowledge of the basic anatomy of the lids is a must. There are different techniques for reconstructing the upper eyelid, lower eyelid, and medial and lateral canthal areas. Many a times, the defects involve more than one area. For the reconstruction of the lid, the lining should be similar to the conjunctiva, a cover by skin and the middle layer to give firmness and support. It is important to understand the availability of various tissues for reconstruction. One layer should have the vascularity to support the other layer which can be a graft. A proper plan and execution of it is very important.

  2. Prairie Reconstruction Initiative

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of the Prairie Reconstruction Initiative Advisory Team (PRIAT) is to identify and take steps to resolve uncertainties in the process of prairie...

  3. Breast Reconstruction After Mastectomy

    Science.gov (United States)

    ... It also does not involve cutting of the abdominal muscle and is a free flap. This type of ... NCI fact sheet Mammograms . What are some new developments in breast reconstruction after mastectomy? Oncoplastic surgery. In ...

  4. Head and face reconstruction

    Science.gov (United States)

    ... work together. Head and neck surgeons also perform craniofacial reconstruction operations. The surgery is done while you are deep asleep and pain-free (under general anesthesia ). The surgery may take ...

  5. Reconstruction Setting Out

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The earthquake-hit Yushu shifts its focus from rescuing survivors to post-quake reconstruction The first phase of earthquake relief, in which rescuing lives was the priority, finished 12 days after a 7.1-magnitude earthquake struck the Tibetan Autonomous Prefecture of Yushu in northwest China’s Qinghai Province on April 14, and reconstruction of the area is now ready to begin.

  6. The Prevention of Blindness-Past, Present and Future

    Institute of Scientific and Technical Information of China (English)

    Akira; Nakajima

    1992-01-01

    Prevention of blindness is the most important aim of ophthalmology. Prevention of blindness is related to many factors. It is related to many factors, such as science and technology, economy and social behavior. There are worldwide activities by WHO, NGOs and other functions to promote the prevention of blindness in the world. More than 90% of blind population lives in developing world. Cataract is the top causes of blindness which is curable. Onchocerciasis is an endemic disease in west Africa and cent...

  7. Tactile Sensitivity and Braille Reading in People with Early Blindness and Late Blindness

    Science.gov (United States)

    Oshima, Kensuke; Arai, Tetsuya; Ichihara, Shigeru; Nakano, Yasushi

    2014-01-01

    Introduction: The inability to read quickly can be a disadvantage throughout life. This study focused on the associations of braille reading fluency and individual factors, such as the age at onset of blindness and number of years reading braille, and the tactile sensitivity of people with early and late blindness. The relationship between reading…

  8. Primordial density and BAO reconstruction

    CERN Document Server

    Zhu, Hong-Ming; Chen, Xuelei

    2016-01-01

    We present a new method to reconstruct the primordial (linear) density field using the estimated nonlinear displacement field. The divergence of the displacement field gives the reconstructed density field. We solve the nonlinear displacement field in the 1D cosmology and show the reconstruction results. The new reconstruction algorithm recovers a lot of linear modes and reduces the nonlinear damping scale significantly. The successful 1D reconstruction results imply the new algorithm should also be a promising technique in the 3D case.

  9. Rapid Assessment of Avoidable Blindness in India.

    Directory of Open Access Journals (Sweden)

    John Neena

    Full Text Available BACKGROUND: Rapid assessment of avoidable blindness provides valid estimates in a short period of time to assess the magnitude and causes of avoidable blindness. The study determined magnitude and causes of avoidable blindness in India in 2007 among the 50+ population. METHODS AND FINDINGS: Sixteen randomly selected districts where blindness surveys were undertaken 7 to 10 years earlier were identified for a follow up survey. Stratified cluster sampling was used and 25 clusters (20 rural and 5 urban were randomly picked in each district.. After a random start, 100 individuals aged 50+ were enumerated and examined sequentially in each cluster. All those with presenting vision = 50 years were enumerated, and 94.7% examined. Based on presenting vision,, 4.4% (95% Confidence Interval[CI]: 4.1,4.8 were severely visually impaired (vision<6/60 to 3/60 in the better eye and 3.6% (95% CI: 3.3,3.9 were blind (vision<3/60 in the better eye. Prevalence of low vision (<6/18 to 6/60 in the better eye was 16.8% (95% CI: 16.0,17.5. Prevalence of blindness and severe visual impairment (<6/60 in the better eye was higher among rural residents (8.2%; 95% CI: 7.9,8.6 compared to urban (7.1%; 95% CI: 5.0, 9.2, among females (9.2%; 95% CI: 8.6,9.8 compared to males (6.5%; 95% CI: 6.0,7.1 and people above 70 years (20.6%; 95% CI: 19.1,22.0 compared to people aged 50-54 years (1.3%; 95% CI: 1.1,1.6. Of all blindness, 88.2% was avoidable. of which 81.9% was due to cataract and 7.1% to uncorrected refractive errors/uncorrected aphakia. CONCLUSIONS: Cataract and refractive errors are major causes of blindness and low vision and control strategies should prioritize them. Most blindness and low vision burden is avoidable.

  10. Turning the tide of corneal blindness

    Directory of Open Access Journals (Sweden)

    Matthew S Oliva

    2012-01-01

    Full Text Available Corneal diseases represent the second leading cause of blindness in most developing world countries. Worldwide, major investments in public health infrastructure and primary eye care services have built a strong foundation for preventing future corneal blindness. However, there are an estimated 4.9 million bilaterally corneal blind persons worldwide who could potentially have their sight restored through corneal transplantation. Traditionally, barriers to increased corneal transplantation have been daunting, with limited tissue availability and lack of trained corneal surgeons making widespread keratoplasty services cost prohibitive and logistically unfeasible. The ascendancy of cataract surgical rates and more robust eye care infrastructure of several Asian and African countries now provide a solid base from which to dramatically expand corneal transplantation rates. India emerges as a clear global priority as it has the world′s largest corneal blind population and strong infrastructural readiness to rapidly scale its keratoplasty numbers. Technological modernization of the eye bank infrastructure must follow suit. Two key factors are the development of professional eye bank managers and the establishment of Hospital Cornea Recovery Programs. Recent adaptation of these modern eye banking models in India have led to corresponding high growth rates in the procurement of transplantable tissues, improved utilization rates, operating efficiency realization, and increased financial sustainability. The widespread adaptation of lamellar keratoplasty techniques also holds promise to improve corneal transplant success rates. The global ophthalmic community is now poised to scale up widespread access to corneal transplantation to meet the needs of the millions who are currently blind.

  11. Turning the tide of corneal blindness.

    Science.gov (United States)

    Oliva, Matthew S; Schottman, Tim; Gulati, Manoj

    2012-01-01

    Corneal diseases represent the second leading cause of blindness in most developing world countries. Worldwide, major investments in public health infrastructure and primary eye care services have built a strong foundation for preventing future corneal blindness. However, there are an estimated 4.9 million bilaterally corneal blind persons worldwide who could potentially have their sight restored through corneal transplantation. Traditionally, barriers to increased corneal transplantation have been daunting, with limited tissue availability and lack of trained corneal surgeons making widespread keratoplasty services cost prohibitive and logistically unfeasible. The ascendancy of cataract surgical rates and more robust eye care infrastructure of several Asian and African countries now provide a solid base from which to dramatically expand corneal transplantation rates. India emerges as a clear global priority as it has the world's largest corneal blind population and strong infrastructural readiness to rapidly scale its keratoplasty numbers. Technological modernization of the eye bank infrastructure must follow suit. Two key factors are the development of professional eye bank managers and the establishment of Hospital Cornea Recovery Programs. Recent adaptation of these modern eye banking models in India have led to corresponding high growth rates in the procurement of transplantable tissues, improved utilization rates, operating efficiency realization, and increased financial sustainability. The widespread adaptation of lamellar keratoplasty techniques also holds promise to improve corneal transplant success rates. The global ophthalmic community is now poised to scale up widespread access to corneal transplantation to meet the needs of the millions who are currently blind.

  12. Augmented Likelihood Image Reconstruction.

    Science.gov (United States)

    Stille, Maik; Kleine, Matthias; Hägele, Julian; Barkhausen, Jörg; Buzug, Thorsten M

    2016-01-01

    The presence of high-density objects remains an open problem in medical CT imaging. Data of projections passing through objects of high density, such as metal implants, are dominated by noise and are highly affected by beam hardening and scatter. Reconstructed images become less diagnostically conclusive because of pronounced artifacts that manifest as dark and bright streaks. A new reconstruction algorithm is proposed with the aim to reduce these artifacts by incorporating information about shape and known attenuation coefficients of a metal implant. Image reconstruction is considered as a variational optimization problem. The afore-mentioned prior knowledge is introduced in terms of equality constraints. An augmented Lagrangian approach is adapted in order to minimize the associated log-likelihood function for transmission CT. During iterations, temporally appearing artifacts are reduced with a bilateral filter and new projection values are calculated, which are used later on for the reconstruction. A detailed evaluation in cooperation with radiologists is performed on software and hardware phantoms, as well as on clinically relevant patient data of subjects with various metal implants. Results show that the proposed reconstruction algorithm is able to outperform contemporary metal artifact reduction methods such as normalized metal artifact reduction.

  13. Blind source separation of multichannel electroencephalogram based on wavelet transform and ICA

    Science.gov (United States)

    You, Rong-Yi; Chen, Zhong

    2005-11-01

    Combination of the wavelet transform and independent component analysis (ICA) was employed for blind source separation (BSS) of multichannel electroencephalogram (EEG). After denoising the original signals by discrete wavelet transform, high frequency components of some noises and artifacts were removed from the original signals. The denoised signals were reconstructed again for the purpose of ICA, such that the drawback that ICA cannot distinguish noises from source signals can be overcome effectively. The practical processing results showed that this method is an effective way to BSS of multichannel EEG. The method is actually a combination of wavelet transform with adaptive neural network, so it is also useful for BBS of other complex signals.

  14. US and MDCT findings in a caudal blind ending bifid ureter with calculi

    Directory of Open Access Journals (Sweden)

    Caglar Uzun

    2011-09-01

    Full Text Available Herein we present a rare ureteric duplication anomaly; blind ending bifid ureter with calculi which is asymptomatic unless complicated by infection, reflux, calculi or malignancy. The diagnosis is often missed at intravenous urography (IVU and US because the ipsilateral ureter and kidney are grossly normal. In this case the diagnosis was established with ultrasound (US and mainly with multidetector computerized tomography (MDCT imaging using multiplanar reformats and 3-D reconstructions which were unique to this case. MDCT scans not only revealed the exact diagnosis and anatomic relationships but also ruled out other pathologies included in the differential diagnosis as well, such as ureter and bladder diverticula.

  15. US and MDCT findings in a caudal blind ending bifid ureter with calculi

    Directory of Open Access Journals (Sweden)

    Evren Ustuner

    2011-11-01

    Full Text Available Herein we present a rare ureteric duplication anomaly; blind ending bifid ureter with calculi which is asymptomatic unless complicated by infection, reflux, calculi or malignancy. The diagnosis is often missed at intravenous urography (IVU and US because the ipsilateral ureter and kidney are grossly normal. In this case the diagnosis was established with ultrasound (US and mainly with multidetector computerized tomography (MDCT imaging using multiplanar reformats and 3-D reconstructions which were unique to this case. MDCT scans not only revealed the exact diagnosis and anatomic relationships but also ruled out other pathologies included in the differential diagnosis as well, such as ureter and bladder diverticula.

  16. Blind source separation of multichannel electroencephalogram based on wavelet transform and ICA

    Institute of Scientific and Technical Information of China (English)

    You Rong-Yi; Chen Zhong

    2005-01-01

    Combination of the wavelet transform and independent component analysis (ICA) was employed for blind source separation (BSS) of multichannel electroencephalogram (EEG). After denoising the original signals by discrete wavelet transform, high frequency components of some noises and artifacts were removed from the original signals. The denoised signals were reconstructed again for the purpose of ICA, such that the drawback that ICA cannot distinguish noises from source signals can be overcome effectively. The practical processing results showed that this method is an effective way to BSS of multichannel EEG. The method is actually a combination of wavelet transform with adaptive neural network, so it is also useful for BBS of other complex signals.

  17. Fruit fly optimization based least square support vector regression for blind image restoration

    Science.gov (United States)

    Zhang, Jiao; Wang, Rui; Li, Junshan; Yang, Yawei

    2014-11-01

    The goal of image restoration is to reconstruct the original scene from a degraded observation. It is a critical and challenging task in image processing. Classical restorations require explicit knowledge of the point spread function and a description of the noise as priors. However, it is not practical for many real image processing. The recovery processing needs to be a blind image restoration scenario. Since blind deconvolution is an ill-posed problem, many blind restoration methods need to make additional assumptions to construct restrictions. Due to the differences of PSF and noise energy, blurring images can be quite different. It is difficult to achieve a good balance between proper assumption and high restoration quality in blind deconvolution. Recently, machine learning techniques have been applied to blind image restoration. The least square support vector regression (LSSVR) has been proven to offer strong potential in estimating and forecasting issues. Therefore, this paper proposes a LSSVR-based image restoration method. However, selecting the optimal parameters for support vector machine is essential to the training result. As a novel meta-heuristic algorithm, the fruit fly optimization algorithm (FOA) can be used to handle optimization problems, and has the advantages of fast convergence to the global optimal solution. In the proposed method, the training samples are created from a neighborhood in the degraded image to the central pixel in the original image. The mapping between the degraded image and the original image is learned by training LSSVR. The two parameters of LSSVR are optimized though FOA. The fitness function of FOA is calculated by the restoration error function. With the acquired mapping, the degraded image can be recovered. Experimental results show the proposed method can obtain satisfactory restoration effect. Compared with BP neural network regression, SVR method and Lucy-Richardson algorithm, it speeds up the restoration rate and

  18. Non-blind watermarking of network flows

    CERN Document Server

    Houmansadr, Amir; Borisov, Nikita

    2012-01-01

    Linking network flows is an important problem in intrusion detection as well as anonymity. Passive traffic analysis can link flows but requires long periods of observation to reduce errors. Active traffic analysis, also known as flow watermarking, allows for better precision and is more scalable. Previous flow watermarks introduce significant delays to the traffic flow as a side effect of using a blind detection scheme; this enables attacks that detect and remove the watermark, while at the same time slowing down legitimate traffic. We propose the first non-blind approach for flow watermarking, called RAINBOW, that improves watermark invisibility by inserting delays hundreds of times smaller than previous blind watermarks, hence reduces the watermark interference on network flows. We derive and analyze the optimum detectors for RAINBOW as well as the passive traffic analysis under different traffic models by using hypothesis testing. Comparing the detection performance of RAINBOW and the passive approach we o...

  19. Experimental demonstration of blind quantum computing

    Science.gov (United States)

    Barz, Stefanie; Kashefi, Elham; Broadbent, Anne; Fitzsimons, Joe; Zeilinger, Anton; Walther, Philip

    2012-02-01

    Quantum computers are among the most promising applications of quantum-enhanced technologies. Quantum effects such as superposition and entanglement enable computational speed-ups that are unattainable using classical computers. The challenges in realising quantum computers suggest that in the near future, only a few facilities worldwide will be capable of operating such devices. In order to exploit these computers, users would seemingly have to give up their privacy. It was recently shown that this is not the case and that, via the universal blind quantum computation protocol, quantum mechanics provides a way to guarantee that the user's data remain private. Here, we demonstrate the first experimental version of this protocol using polarisation-entangled photonic qubits. We demonstrate various blind one- and two-qubit gate operations as well as blind versions of the Deutsch's and Grover's algorithms. When the technology to build quantum computers becomes available, this will become an important privacy-preserving feature of quantum information processing.

  20. Brief mindfulness induction reduces inattentional blindness.

    Science.gov (United States)

    Schofield, Timothy P; Creswell, J David; Denson, Thomas F

    2015-12-01

    Prior research has linked mindfulness to improvements in attention, and suggested that the effects of mindfulness are particularly pronounced when individuals are cognitively depleted or stressed. Yet, no studies have tested whether mindfulness improves declarative awareness of unexpected stimuli in goal-directed tasks. Participants (N=794) were either depleted (or not) and subsequently underwent a brief mindfulness induction (or not). They then completed an inattentional blindness task during which an unexpected distractor appeared on the computer monitor. This task was used to assess declarative conscious awareness of the unexpected distractor's presence and the extent to which its perceptual properties were encoded. Mindfulness increased awareness of the unexpected distractor (i.e., reduced rates of inattentional blindness). Contrary to predictions, no mindfulness×depletion interaction emerged. Depletion however, increased perceptual encoding of the distractor. These results suggest that mindfulness may foster awareness of unexpected stimuli (i.e., reduce inattentional blindness).

  1. No such thing as a "blind culture".

    Science.gov (United States)

    Weisleder, Pedro

    2012-06-01

    Cochlear implant technology has altered the landscape for the Deaf and for those who provide services to the profoundly hearing impaired. As indicated by Teagle in one of the companion articles, cochlear implants afford the profoundly hearing impaired child the ability to circumvent the effects of deafness. Cochlear implants, as indicated by Lee in the other companion article, are regarded differently by members of the Deaf Community where some see the technology as a threat to Deaf Culture. Members of a different community, which comprises the visually impaired, cite lack of a common language as the main argument against the existence of a "Blind Culture." As indicated by Pierce "We [the blind] often enjoy each other's company, and we certainly spend time together working on the problems that face what we often call the 'blind community,' but I would argue that this community is different from an actual culture."

  2. Blindness and cataract in children in developing countries

    Directory of Open Access Journals (Sweden)

    Parikshit Gogate

    2009-03-01

    Full Text Available Blindness in children is considered a priority area for VISION 2020, as visually impaired children have a lifetime of blindness ahead of them. Various studies across the globe show that one-third to half of childhood blindness is either preventable or treatable1 and that cataract is the leading treatable cause of blindness in children.The 8th General Assembly of the International Agency for the Prevention of Blindness (IAPB provided an opportunity to be acquainted with recent research and programme development work in the prevention of childhood blindness.

  3. Reconstruction of inflation models

    Energy Technology Data Exchange (ETDEWEB)

    Myrzakulov, Ratbay; Sebastiani, Lorenzo [Eurasian National University, Department of General and Theoretical Physics and Eurasian Center for Theoretical Physics, Astana (Kazakhstan); Zerbini, Sergio [Universita di Trento, Dipartimento di Fisica, Trento (Italy); TIFPA, Istituto Nazionale di Fisica Nucleare, Trento (Italy)

    2015-05-15

    In this paper, we reconstruct viable inflationary models by starting from spectral index and tensor-to-scalar ratio from Planck observations. We analyze three different kinds of models: scalar field theories, fluid cosmology, and f(R)-modified gravity. We recover the well-known R{sup 2} inflation in Jordan-frame and Einstein-frame representation, the massive scalar inflaton models and two models of inhomogeneous fluid. A model of R{sup 2} correction to Einstein's gravity plus a ''cosmological constant'' with an exact solution for early-time acceleration is reconstructed. (orig.)

  4. The evolving breast reconstruction

    DEFF Research Database (Denmark)

    Thomsen, Jørn Bo; Gunnarsson, Gudjon Leifur

    2014-01-01

    The aim of this editorial is to give an update on the use of the propeller thoracodorsal artery perforator flap (TAP/TDAP-flap) within the field of breast reconstruction. The TAP-flap can be dissected by a combined use of a monopolar cautery and a scalpel. Microsurgical instruments are generally...... not needed. The propeller TAP-flap can be designed in different ways, three of these have been published: (I) an oblique upwards design; (II) a horizontal design; (III) an oblique downward design. The latissimus dorsi-flap is a good and reliable option for breast reconstruction, but has been criticized...

  5. Vertex Reconstruction in CMS

    CERN Document Server

    Chabanat, E; D'Hondt, J; Vanlaer, P; Prokofiev, K; Speer, T; Frühwirth, R; Waltenberger, W

    2005-01-01

    Because of the high track multiplicity in the final states expected in proton collisions at the LHC experiments, novel vertex reconstruction algorithms are required. The vertex reconstruction problem can be decomposed into a pattern recognition problem ("vertex finding") and an estimation problem ("vertex fitting"). Starting from least-square methods, ways to render the classical algorithms more robust are discussed and the statistical properties of the novel methods are shown. A whole set of different approaches for the vertex finding problem is presented and compared in relevant physics channels.

  6. Upper Eyelid Reconstruction.

    Science.gov (United States)

    Espinoza, Gabriela Mabel; Prost, Angela Michelle

    2016-05-01

    Reconstruction of the upper eyelid is complicated because the eyelid must retain mobility, flexibility, function, and a suitable mucosal surface over the delicate cornea. Defects of the upper eyelid may be due to congenital defects or traumatic injury or follow oncologic resection. This article focuses on reconstruction due to loss of tissue. Multiple surgeries may be needed to reach the desired results, addressing loss of tissue and then loss of function. Each defect is unique and the laxity and availability of surrounding tissue vary. Knowing the most common techniques for repair assists surgeons in the multifaceted planning that takes place.

  7. Natural Gradient Approach to Multichannel Blind Deconvolution

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper we study the geometrical structures of FIR filters and their application to multichannel blind deconvolution.First we introduce a Lie group structure and a Riemannian structure on the manifolds of the FIR filters.Then we derive the natural gradients on the manifolds using the isometry of the Riemannian metric.Using the natural gradient,we present a novel learning algorithm for blind deconvolution based on the minimization of mutual information.Some properties of the learning algorithm,such as equivariance and stability are also studied.Finally,the simulations are given to illustrate the effectiveness and validity of the proposed algorithm.

  8. Transform domain steganography with blind source separation

    Science.gov (United States)

    Jouny, Ismail

    2015-05-01

    This paper applies blind source separation or independent component analysis for images that may contain mixtures of text, audio, or other images for steganography purposes. The paper focuses on separating mixtures in the transform domain such as Fourier domain or the Wavelet domain. The study addresses the effectiveness of steganography when using linear mixtures of multimedia components and the ability of standard blind sources separation techniques to discern hidden multimedia messages. Mixing in the space, frequency, and wavelet (scale) domains is compared. Effectiveness is measured using mean square error rate between original and recovered images.

  9. Blind source separation theory and applications

    CERN Document Server

    Yu, Xianchuan; Xu, Jindong

    2013-01-01

    A systematic exploration of both classic and contemporary algorithms in blind source separation with practical case studies    The book presents an overview of Blind Source Separation, a relatively new signal processing method.  Due to the multidisciplinary nature of the subject, the book has been written so as to appeal to an audience from very different backgrounds. Basic mathematical skills (e.g. on matrix algebra and foundations of probability theory) are essential in order to understand the algorithms, although the book is written in an introductory, accessible style. This book offers

  10. Contrast-induced transient cortical blindness.

    Science.gov (United States)

    Shah, Parth R; Yohendran, Jayshan; Parker, Geoffrey D; McCluskey, Peter J

    2013-05-01

    We present a case of transient cortical blindness secondary to contrast medium toxicity. A 58-year-old man had successful endovascular coiling of a right posterior inferior cerebellar artery aneurysm but became confused and unable to see after the procedure. His visual acuity was no light perception bilaterally. Clinically, there was no new intra-ocular pathology. An urgent non-contrast computed tomography scan of the brain showed cortical hyperdensity in both parieto-occipital cortices, consistent with contrast medium leakage through the blood-brain barrier from the coiling procedure. The man remained completely blind for 72 hours, after which his visual acuity improved gradually back to his baseline level.

  11. Reconstruction Setting Out

    Institute of Scientific and Technical Information of China (English)

    YIN PUMIN

    2010-01-01

    @@ The first phase of earthquake relief,in which rescuing lives was the priority,finished 12 days after a 7.1-magnitude earthquake struck the Tibetan Autonomous Prefecture of Yushu in northwest China's Qinghai Province on April 14,and reconstruction of the area is now ready to begin.

  12. Urogenital Reconstructive Surgery

    DEFF Research Database (Denmark)

    Jakobsen, Lotte Kaasgaard

    Urogenital reconstructive surgery Lotte Kaasgaard Jakobsen1 Professor Henning Olsen1 Overlæge Gitte Hvistendahl1 Professor Karl-Erik Andersson2 1 – Dept. of Urology, Aarhus University Hospital 2 – Dept. of Gynecology and Obstetrics, Aarhus University hospital Background: Congenital obstruction...

  13. Blind parents and nutrition of children: experiences and care

    Directory of Open Access Journals (Sweden)

    Kariane Gomes Cezario

    2016-01-01

    Full Text Available Objective: to understand the experiences of blind parents in care related to breastfeeding and complementary feeding of children. Methods: qualitative research with the participation of four blind mothers and five blind fathers. Home interviews were carried out to address the experience of feeding children in the context of blindness, categorized by the technique of thematic analysis. Results: three categories emerged: Breastfeeding and complementary feeding offered by blind mothers; Blind fathers and the feeding of children; and Care of the children and blindness: coping strategies, in which difficulties and alternatives developed to feed the children were highlighted. Conclusion: blind parents have difficulties similar to those seer parents but with specific demands associated with the handling of utensils in safe and satisfactory supply of food.

  14. Navigation with a sensory substitution device in congenitally blind individuals

    DEFF Research Database (Denmark)

    Chebat, Daniel-Robert; Schneider, Fabien C; Kupers, Ron

    2011-01-01

    Vision allows for obstacle detection and avoidance. The compensatory mechanisms involved in maintaining these functions in blind people using their remaining intact senses are poorly understood. We investigated the ability of congenitally blind participants to detect and avoid obstacles using...

  15. Warming Endotracheal Tube in Blind Nasotracheal Intubation throughout Maxillofacial Surgeries

    Directory of Open Access Journals (Sweden)

    Hamzeh Hosseinzadeh

    2013-12-01

    Conclusion: In conclusion, our study showed that using an endotracheal tube softened by warm water could reduce the incidence and severity of epistaxis during blind nasotracheal intubation; however it could not facilitate blind nasotracheal intubation.

  16. If I am Blind or Deaf

    Institute of Scientific and Technical Information of China (English)

    李新颖

    2005-01-01

    For some time,l wished to be blind or deaf so that I could avoid the sight or the sound from having driven me mad.The majority of people must object the idea that the dark life maybe more beautiful than the life full of limitations and unhappiness.

  17. What It's Like to Be Color Blind

    Science.gov (United States)

    ... see colors properly. When your cones don't work properly, or you don't have the right combination, your brain doesn't get the right message about which colors you're seeing. To someone who's color blind, a green leaf might look tan or gray. ...

  18. The Mediterranean blind: less light, better vision

    Energy Technology Data Exchange (ETDEWEB)

    Coch, H.; Serra, R.; Isalgue, A. [Universidad Politecnica de Cataluna, Escola d`Arquitectura de Barcelona, Barcelona (Spain)

    1998-09-01

    The mediterranean blind is one of the most efficient and sophisticated technical system to allow natural illumination in building. A simple solution permits good visual conditions with low heat gains and high ventilation. This solution shows how in architecture, simple designs following thoroughly understood principles can achieve far more suitable environment results than high-tech solution applied without criteria. (Author)

  19. Blind quantum computing with weak coherent pulses.

    Science.gov (United States)

    Dunjko, Vedran; Kashefi, Elham; Leverrier, Anthony

    2012-05-18

    The universal blind quantum computation (UBQC) protocol [A. Broadbent, J. Fitzsimons, and E. Kashefi, in Proceedings of the 50th Annual IEEE Symposiumon Foundations of Computer Science (IEEE Computer Society, Los Alamitos, CA, USA, 2009), pp. 517-526.] allows a client to perform quantum computation on a remote server. In an ideal setting, perfect privacy is guaranteed if the client is capable of producing specific, randomly chosen single qubit states. While from a theoretical point of view, this may constitute the lowest possible quantum requirement, from a pragmatic point of view, generation of such states to be sent along long distances can never be achieved perfectly. We introduce the concept of ϵ blindness for UBQC, in analogy to the concept of ϵ security developed for other cryptographic protocols, allowing us to characterize the robustness and security properties of the protocol under possible imperfections. We also present a remote blind single qubit preparation protocol with weak coherent pulses for the client to prepare, in a delegated fashion, quantum states arbitrarily close to perfect random single qubit states. This allows us to efficiently achieve ϵ-blind UBQC for any ϵ>0, even if the channel between the client and the server is arbitrarily lossy.

  20. Blind Quantum Computing with Weak Coherent Pulses

    Science.gov (United States)

    Dunjko, Vedran; Kashefi, Elham; Leverrier, Anthony

    2012-05-01

    The universal blind quantum computation (UBQC) protocol [A. Broadbent, J. Fitzsimons, and E. Kashefi, in Proceedings of the 50th Annual IEEE Symposiumon Foundations of Computer Science (IEEE Computer Society, Los Alamitos, CA, USA, 2009), pp. 517-526.] allows a client to perform quantum computation on a remote server. In an ideal setting, perfect privacy is guaranteed if the client is capable of producing specific, randomly chosen single qubit states. While from a theoretical point of view, this may constitute the lowest possible quantum requirement, from a pragmatic point of view, generation of such states to be sent along long distances can never be achieved perfectly. We introduce the concept of ɛ blindness for UBQC, in analogy to the concept of ɛ security developed for other cryptographic protocols, allowing us to characterize the robustness and security properties of the protocol under possible imperfections. We also present a remote blind single qubit preparation protocol with weak coherent pulses for the client to prepare, in a delegated fashion, quantum states arbitrarily close to perfect random single qubit states. This allows us to efficiently achieve ɛ-blind UBQC for any ɛ>0, even if the channel between the client and the server is arbitrarily lossy.

  1. Ask a Scientist: What is Color Blindness?

    Medline Plus

    Full Text Available ... other programs with respect to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health ... Eye Ask a Scientist Video Series Glossary The Visual System Your Eyes’ Natural Defenses Eye Health and ...

  2. Young Blind Children: Towards Assessment for Rehabilitation.

    Science.gov (United States)

    Davidson, Iain F. W. K.; Simmons, Joyce Nesker

    1992-01-01

    This article addresses the unique assessment needs of young blind children and discourages dependence on standardized tests for this population. Principles of one assessment approach (involving observation; clinical examination of mobility, language, play, socioemotional development, and academic skills; and interviews with mother and social…

  3. Potentials of Rubella Deaf-Blind Children.

    Science.gov (United States)

    Smith, Benjamin F.

    Potentials of three classifications of rubella deaf blind children are discussed. Potentials for children at the middle trainable level and below are discussed for the areas of communication skills, daily living skills, mobility and orientation, vocational effort, and self-control and social interaction. For children in the upper trainable through…

  4. Vision after 53 Years of Blindness

    Directory of Open Access Journals (Sweden)

    Radovan Šikl

    2013-12-01

    Full Text Available Several studies have shown that visual recovery after blindness that occurs early in life is never complete. The current study investigated whether an extremely long period of blindness might also cause a permanent impairment of visual performance, even in a case of adult-onset blindness. We examined KP, a 71-year-old man who underwent a successful sight-restoring operation after 53 years of blindness. A set of psychophysical tests designed to assess KP's face perception, object recognition, and visual space perception abilities were conducted six months and eight months after the surgery. The results demonstrate that regardless of a lengthy period of normal vision and rich pre-accident perceptual experience, KP did not fully integrate this experience, and his visual performance remained greatly compromised. This was particularly evident when the tasks targeted finer levels of perceptual processing. In addition to the decreased robustness of his memory representations, which was hypothesized as the main factor determining visual impairment, other factors that may have affected KP's performance were considered, including compromised visual functions, problems with perceptual organization, deficits in the simultaneous processing of visual information, and reduced cognitive abilities.

  5. Automatic Blind Syllable Segmentation for Continuous Speech

    OpenAIRE

    Villing, Rudi; Timoney, Joseph; Ward, Tomas

    2004-01-01

    In this paper a simple practical method for blind segmentation of continuous speech into its constituent syllables is presented. This technique which uses amplitude onset velocity and coarse spectral makeup to identify syllable boundaries is tested on a corpus of continuous speech and compared with an established segmentation algorithm. The results show substantial performance benefit using the proposed algorithm.

  6. Functional rehabilitation of partial cortical blindness?

    Science.gov (United States)

    Stoerig, Petra

    2008-01-01

    The current doctrine regards fields of partial cortical blindness as permanent once a temporally restricted window for spontaneous recovery has passed. Accordingly, neuropsychological rehabilitation mainly applies compensatory procedures that train patients to make better use of their sighted field. The more ambitious goal of functional recovery depends on the survival of pathways that continue to transmit retinal information from the blind field. Although wide-spread antero- and retrograde degeneration follows lesions that destroy or denervate the primary visual cortex and cause partial cortical blindness, several retinofugal pathways survive in cats, monkeys, and humans. In all three species, they subserve a variety of visual functions which develop and improve with practice. Post lesion plasticity is greater when the lesion occurs early in life, but changes in behavioural performance and brain responses have also been demonstrated in late lesion subjects. Although the extent of functional improvement is variable, and the most effective approaches still need to be established across cohorts, the evidence for perceptual learning in fields of cortical blindness indicates that the visual processes mediated by the surviving parts of the visual system can be harnessed to improve functional outcome.

  7. Preparing for Breast Reconstruction Surgery

    Science.gov (United States)

    ... Cancer Breast Reconstruction Surgery Preparing for Breast Reconstruction Surgery Your surgeon can help you know what to ... The plan for follow-up Costs Understanding your surgery costs Health insurance policies often cover most or ...

  8. The genome of Onchocerca volvulus, agent of river blindness

    Science.gov (United States)

    Cotton, James A.; Bennuru, Sasisekhar; Grote, Alexandra; Harsha, Bhavana; Tracey, Alan; Beech, Robin; Doyle, Stephen R.; Dunn, Matthew; Dunning Hotopp, Julie C.; Holroyd, Nancy; Kikuchi, Taisei; Lambert, Olivia; Mhashilkar, Amruta; Mutowo, Prudence; Nursimulu, Nirvana; Ribeiro, Jose M. C.; Rogers, Matthew B.; Stanley, Eleanor; Swapna, Lakshmipuram S.; Tsai, Isheng J.; Unnasch, Thomas R.; Voronin, Denis; Parkinson, John; Nutman, Thomas B.; Ghedin, Elodie; Berriman, Matthew; Lustigman, Sara

    2017-01-01

    Human onchocerciasis is a serious neglected tropical disease caused by the filarial nematode Onchocerca volvulus that can lead to blindness and chronic disability. Control of the disease relies largely on mass administration of a single drug, and the development of new drugs and vaccines depends on a better knowledge of parasite biology. Here, we describe the chromosomes of O. volvulus and its Wolbachia endosymbiont. We provide the highest-quality sequence assembly for any parasitic nematode to date, giving a glimpse into the evolution of filarial parasite chromosomes and proteomes. This resource was used to investigate gene families with key functions that could be potentially exploited as targets for future drugs. Using metabolic reconstruction of the nematode and its endosymbiont, we identified enzymes that are likely to be essential for O. volvulus viability. In addition, we have generated a list of proteins that could be targeted by Federal-Drug-Agency-approved but repurposed drugs, providing starting points for anti-onchocerciasis drug development. PMID:27869790

  9. Complex-wave retrieval based on blind signal separation

    Institute of Scientific and Technical Information of China (English)

    Xiaodong Chai; Chengpeng Zhou; Zhaoyan Feng; Yinhua Wang; Yansheng Zuo

    2006-01-01

    In the process of the reconstruction of digital holography, the traditional methods of diffraction and filtration are commonly adopted to recover the original complex-wave signal. Influenced by twin-image and zero-order terms, the above-mentioned methods, however, either limit the field of vision or result in the loss of the amplitude and phase. A new method for complex-wave retrieval is presented, which is based on blind signal separation. Three frames of holograms are captured by a charge coupled device (CCD)camera to form an observation signal. The term containing only amplitude and phase of complex-wave is separated, by means of independent component analysis, from the observation signal, which effectively eliminates the zero-order term. Finally, the complex-wave retrieval of pure phase wavefront is achieved.Experimental results show that this method can better recover the amplitude and phase of the original complex-wave even when there is a frequency spectrum mixture in the hologram.

  10. Rapid assessment of avoidable blindness in Western Rwanda: blindness in a postconflict setting.

    Directory of Open Access Journals (Sweden)

    Wanjiku Mathenge

    2007-07-01

    Full Text Available BACKGROUND: The World Health Organization estimates that there were 37 million blind people in 2002 and that the prevalence of blindness was 9% among adults in Africa aged 50 years or older. Recent surveys indicate that this figure may be overestimated, while a survey from southern Sudan suggested that postconflict areas are particularly vulnerable to blindness. The aim of this study was to conduct a Rapid Assessment for Avoidable Blindness to estimate the magnitude and causes of visual impairment in people aged > or = 50 y in the postconflict area of the Western Province of Rwanda, which includes one-quarter of the population of Rwanda. METHODS AND FINDINGS: Clusters of 50 people aged > or = 50 y were selected through probability proportionate to size sampling. Households within clusters were selected through compact segment sampling. Visual acuity (VA was measured with a tumbling "E" chart, and those with VA below 6/18 in either eye were examined by an ophthalmologist. The teams examined 2,206 people (response rate 98.0%. The unadjusted prevalence of bilateral blindness was 1.8% (95% confidence interval [CI] 1.2%-2.4%, 1.3% (0.8%-1.7% for severe visual impairment, and 5.3% (4.2%-6.4% for visual impairment. Most bilateral blindness (65% was due to cataract. Overall, the vast majority of cases of blindness (80.0%, severe visual impairment (67.9%, and visual impairment (87.2% were avoidable (i.e.. due to cataract, refractive error, aphakia, trachoma, or corneal scar. The cataract surgical coverage was moderate; 47% of people with bilateral cataract blindness (VA < 3/60 had undergone surgery. Of the 29 eyes that had undergone cataract surgery, nine (31% had a best-corrected poor outcome (i.e., VA < 6/60. Extrapolating these estimates to Rwanda's Western Province, among the people aged 50 years or above 2,565 are expected to be blind, 1,824 to have severe visual impairment, and 8,055 to have visual impairment. CONCLUSIONS: The prevalence of

  11. 34 CFR 395.11 - Training program for blind individuals.

    Science.gov (United States)

    2010-07-01

    ... education and additional training or retraining for improved work opportunities) for all blind licensees... 34 Education 2 2010-07-01 2010-07-01 false Training program for blind individuals. 395.11 Section... BLIND ON FEDERAL AND OTHER PROPERTY The State Licensing Agency § 395.11 Training program for...

  12. 77 FR 42187 - Relay Services for Deaf-Blind Individuals

    Science.gov (United States)

    2012-07-18

    ... COMMISSION 47 CFR Part 64 Relay Services for Deaf-Blind Individuals AGENCY: Federal Communications Commission... Communications and Video Accessibility Act of 2010, Section 105, Relay Services for Deaf-Blind Individuals, Order... Services for Deaf-Blind Individuals, CG Docket No. 10-210. Form Number: N/A. Type of Review: Revision of...

  13. 76 FR 31261 - Relay Services for Deaf-Blind Individuals

    Science.gov (United States)

    2011-05-31

    ... COMMISSION 47 CFR Part 64 Relay Services for Deaf-Blind Individuals AGENCY: Federal Communications Commission... to establish the National Deaf-Blind Equipment Distribution Program (NDBEDP) pilot program in... environments shall be considered when determining whether the individual is deaf-blind under clauses...

  14. Ya "See" What We Mean: Teaching the Blind to Ski.

    Science.gov (United States)

    Pringle, Doug; Winthers, Jim

    The illustrated manual contains instructions for teaching blind and partially sighted students to ski. It is noted that blind students should be coached, instructed, and encouraged in the same manner as sighted students although additional safety precautions should be employed. Psychological implications for the blind student learning to ski are…

  15. Information-Dispersion-Entropy-Based Blind Recognition of Binary BCH Codes in Soft Decision Situations

    Directory of Open Access Journals (Sweden)

    Yimeng Zhang

    2013-05-01

    Full Text Available A method of blind recognition of the coding parameters for binary Bose-Chaudhuri-Hocquenghem (BCH codes is proposed in this paper. We consider an intelligent communication receiver which can blindly recognize the coding parameters of the received data stream. The only knowledge is that the stream is encoded using binary BCH codes, while the coding parameters are unknown. The problem can be addressed on the context of the non-cooperative communications or adaptive coding and modulations (ACM for cognitive radio networks. The recognition processing includes two major procedures: code length estimation and generator polynomial reconstruction. A hard decision method has been proposed in a previous literature. In this paper we propose the recognition approach in soft decision situations with Binary-Phase-Shift-Key modulations and Additive-White-Gaussian-Noise (AWGN channels. The code length is estimated by maximizing the root information dispersion entropy function. And then we search for the code roots to reconstruct the primitive and generator polynomials. By utilizing the soft output of the channel, the recognition performance is improved and the simulations show the efficiency of the proposed algorithm.

  16. Autograft versus allograft in anterior cruciate ligament reconstruction

    Science.gov (United States)

    Kan, Shun-Li; Yuan, Zhi-Fang; Ning, Guang-Zhi; Yang, Bo; Li, Hai-Liang; Sun, Jing-Cheng; Feng, Shi-Qing

    2016-01-01

    Abstract Background: Anterior cruciate ligament (ACL) reconstruction is considered as the standard surgical procedure for the treatment of ACL tear. However, there is a crucial controversy in terms of whether to use autograft or allograft in ACL reconstruction. The purpose of this meta-analysis is to compare autograft with allograft for patients undergoing ACL reconstruction. Methods: PubMed, EMBASE, and the Cochrane Library were searched for randomized controlled trials that compared autograft with allograft in ACL reconstruction up to January 31, 2016. The relative risk or mean difference with 95% confidence interval was calculated using either a fixed- or random-effects model. The risk of bias for individual studies according to the Cochrane Handbook. The trial sequential analysis was used to test the robustness of our findings and get more conservative estimates. Results: Thirteen trials were included, involving 1636 participants. The results of this meta-analysis indicated that autograft brought about lower clinical failure, better overall International Knee Documentation Committee (IKDC) level, better pivot-shift test, better Lachman test, greater Tegner score, and better instrumented laxity test (P allograft. Autograft was not statistically different from allograft in Lysholm score, subjective IKDC score, and Daniel 1-leg hop test (P > 0.05). Subgroup analyses demonstrated that autograft was superior to irradiated allograft for patients undergoing ACL reconstruction in clinical failure, Lysholm score, pivot-shift test, Lachman test, Tegner score, instrumented laxity test, and subjective IKDC score (P allograft. Conclusions: Autograft is superior to irradiated allograft for patients undergoing ACL reconstruction concerning knee function and laxity, but there are no significant differences between autograft and nonirradiated allograft. However, our results should be interpreted with caution, because the blinding methods were not well used. PMID

  17. Arctic Sea Level Reconstruction

    DEFF Research Database (Denmark)

    Svendsen, Peter Limkilde

    method.For oceanographic purposes, the altimetric record over the Arctic Ocean is inferiorin quality to that of moderate latitudes, but nonetheless an invaluable set of observations. During this project, newly processed Arctic altimetry from the ERS-1/-2 and Envisat missions has become available......Reconstruction of historical Arctic sea level is very difficult due to the limited coverage and quality of tide gauge and altimetry data in the area. This thesis addresses many of these issues, and discusses strategies to help achieve a stable and plausible reconstruction of Arctic sea level from...... 1950 to today.The primary record of historical sea level, on the order of several decades to a few centuries, is tide gauges. Tide gauge records from around the world are collected in the Permanent Service for Mean Sea Level (PSMSL) database, and includes data along the Arctic coasts. A reasonable...

  18. Autologous Costochondral Microtia Reconstruction.

    Science.gov (United States)

    Patel, Sapna A; Bhrany, Amit D; Murakami, Craig S; Sie, Kathleen C Y

    2016-04-01

    Reconstruction with autologous costochondral cartilage is one of the mainstays of surgical management of congenital microtia. We review the literature, present our current technique for microtia reconstruction with autologous costochondral graft, and discuss the evolution of our technique over the past 20 years. We aim to minimize donor site morbidity and create the most durable and natural appearing ear possible using a stacked framework to augment the antihelical fold and antitragal-tragal complex. Assessment of outcomes is challenging due to the paucity of available objective measures with which to evaluate aesthetic outcomes. Various instruments are used to assess outcomes, but none is universally accepted as the standard. The challenges we continue to face are humbling, but ongoing work on tissue engineering, application of 3D models, and use of validated questionnaires can help us get closer to achieving a maximal aesthetic outcome.

  19. Stochastic reconstruction of sandstones

    Science.gov (United States)

    Manwart; Torquato; Hilfer

    2000-07-01

    A simulated annealing algorithm is employed to generate a stochastic model for a Berea sandstone and a Fontainebleau sandstone, with each a prescribed two-point probability function, lineal-path function, and "pore size" distribution function, respectively. We find that the temperature decrease of the annealing has to be rather quick to yield isotropic and percolating configurations. A comparison of simple morphological quantities indicates good agreement between the reconstructions and the original sandstones. Also, the mean survival time of a random walker in the pore space is reproduced with good accuracy. However, a more detailed investigation by means of local porosity theory shows that there may be significant differences of the geometrical connectivity between the reconstructed and the experimental samples.

  20. Reconstructing the Tengger calendar

    Directory of Open Access Journals (Sweden)

    Ian Proudfoot

    2008-12-01

    Full Text Available The survival of an Indic calendar among the Tengger people of the Brama highlands in east Java opens a window on Java’s calendar history. Its hybrid form reflects accommodations between this non-Muslim Javanese group and the increasingly dominant Muslim Javanese culture. Reconstruction is challenging because of this hybridity, because of inconsistencies in practice, and because the historical evidence is sketchy and often difficult to interpret.

  1. Left-handedness in blind and sighted children.

    Science.gov (United States)

    Caliskan, Erkan; Dane, Senol

    2009-03-01

    Rates of left-handedness were compared in 1387 blind and 831 sighted children. The rate in male blind children was higher than in female blind children. The incidence of left-handedness was significantly higher in blind than in sighted children in both boys and girls. The percentages of left-handedness were 18.23% and 17.02% in male and female blind children, and 11.02% and 7.52% in male and female sighted children, respectively. It can be stated that sighting is important in the development of normal typical cerebral lateralisation or hand preference.

  2. A New ID-Based Proxy Blind Signature Scheme

    Institute of Scientific and Technical Information of China (English)

    LANG Wei-min; YANG Zong-kai; CHENG Wen-qing; TAN Yun-meng

    2005-01-01

    An identity-based proxy blind signature scheme from bilinear pairings is introduced, which combines the advantages of proxy signature and blind signature. Furthermore, our scheme can prevent the original signer from generating the proxy blind signature, thus the profits of the proxy signer are guaranteed. We introduce bilinear pairings to minimize computational overhead and to improve the related performance of our scheme. In addition, the proxy blind signature presented is non-repudiable and it fulfills perfectly the security requirements of a proxy blind signature.

  3. Canal Wall Reconstruction Mastoidectomy

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective To investigate the advantages of canal wall reconstruction (CWR) mastoidectomy, a single-stage technique for cholesteatoma removal and posterior external canal wall reconstruction, over the open and closed procedures in terms of cholesteatoma recurrence. Methods: Between June 2002 and December 2005, 38 patients (40 ears) with cholesteatoma were admited to Sun Yat-Sen Memorial Hospital and received surgical treatments. Of these patients, 25 were male with ages ranging between 11 and 60 years (mean = 31.6 years) and 13 were female with ages ranging between 20 and 65 years (mean = 38.8 years). Canal wall reconstruction (CWR)mastoidectomy was performed in 31 ears and canal wall down (CWD) mastoidectomy in 9 ears. Concha cartilage was used for ear canal wall reconstruction in 22 of the 31 CWR procedures and cortical mastoid bone was used in the remaining 9 cases. Results At 0.5 to 4 years follow up, all but one patients remained free of signs of cholesteatoma recurrence, i.e., no retraction pocket or cholesteatoma matrix. One patient, a smoker, needed revision surgery due to cholesteatoma recurrence 1.5 year after the initial operation. The recurrence rate was therefore 3.2% (1/31). Cholesteatoma recurrence was monitored using postoperative CT scans whenever possible. In the case that needed a revision procedure, a retraction pocket was identified by otoendoscopy in the pars flacida area that eventually evolved into a cholesteatoma. A pocket extending to the epitympanum filled with cholesteatoma matrix was confirmed during the revision operation, A decision to perform a modified mastoidectomy was made as the patient refused to quit smoking. The mean air-bone gap in pure tone threshold was 45 dB before surgery and 25 dB after (p < 0.05). There was no difference between using concha cartilage and cortical mastoid bone for the reconstruction regarding air-bone gap improvement, CT findings and otoendoscopic results. Conclusion CWR mastoidectomy can be used for

  4. Posteromedial Corner Reconstruction

    Science.gov (United States)

    Ferrer, Gonzalo; Leon, Agustín; Wirth, Hans; Mena, Adolfo; Tuca, María José; Espinoza, Gonzalo

    2017-01-01

    Objective: Report the experience, after 1-year follow-up, of 30 patients who underwent anatomical knee reconstruction of posteromedial corner (PMC) injuries, using La Prade´s Technique. Methods: Retrospective cohort study of 30 consecutive patients with PMC injuries operated between November 2010 and May 2014 by the same surgical team. Inclusion criteria: patients with clinical presentation and images (stress radiographs and MRI) compatible with PMC injury, who maintained a grade III chronic instability in spite of at least 3 months of orthopedic treatment, who were reconstructed using La Prade’s anatomical technique, and completed at least 12 months of follow-up. Exclusion criteria: discordance between clinical and image studies, grade I or II medial instability, and surgery performed through a different technique. Data was collected by reviewing the electronic files and images. Functional scores (IKDC and Lysholm) were applied and registered in the preoperative evaluation, and then 6 and 12 months after surgery. Results: Thirty patients (28 men and 2 women) met the inclusion criteria. Mean age was 43 years (24-69). The vast majority (28 patients) had a high-energy mechanism of injury. Twenty patients were diagnosed in the acute setting, while 10 had a delayed diagnosis after poor results of concomitant ligament reconstructions. With the exception of 2 patients, who presented with isolated PMC injury, the majority had associated injuries as detailed: 11 cases had PMC + anterior cruciate ligament (ACL) injury, 3 patients had PMC + posterior cruciate ligament (PCL) injury, 3 patients had PMC + meniscal tears, 9 patients had PMC + ACL + PCL injuries, and there were 2 cases of PMC + ACL + PCL + lateral collateral ligament injuries. Mean time for PMC reconstruction surgery was 5 months (range 2-32). Lysholm and IKDC scores were 18,2 (2-69) and 24,3 (9,2-52,9) respectively in the preoperative setting, improving to 76,7 (44-94) and 70,7 (36,8-95,4) after 1-year follow

  5. Retrieval and phenomenology of autobiographical memories in blind individuals.

    Science.gov (United States)

    Tekcan, Ali Í; Yılmaz, Engin; Kızılöz, Burcu Kaya; Karadöller, Dilay Z; Mutafoğlu, Merve; Erciyes, Aslı Aktan

    2015-01-01

    Although visual imagery is argued to be an essential component of autobiographical memory, there have been surprisingly few studies on autobiographical memory processes in blind individuals, who have had no or limited visual input. The purpose of the present study was to investigate how blindness affects retrieval and phenomenology of autobiographical memories. We asked 48 congenital/early blind and 48 sighted participants to recall autobiographical memories in response to six cue words, and to fill out the Autobiographical Memory Questionnaire measuring a number of variables including imagery, belief and recollective experience associated with each memory. Blind participants retrieved fewer memories and reported higher auditory imagery at retrieval than sighted participants. Moreover, within the blind group, participants with total blindness reported higher auditory imagery than those with some light perception. Blind participants also assigned higher importance, belief and recollection ratings to their memories than sighted participants. Importantly, these group differences remained the same for recent as well as childhood memories.

  6. Latent Images, Blind Comments on Photography

    Directory of Open Access Journals (Sweden)

    Jenny Feray

    2013-12-01

    Full Text Available Photographs, or images as the final result of a process, merely mark out the moment when the eye is helplessly limited to what it sees. Thus, what escapes the eye in the physical sense, i.e. what the eye will never see, is what occurs before the product- image, within the act itself. The latent image, the desire-image, unfolds throughout the duration of the photographic act. When the picture is ‘taken’, then the desire subsides until the next desire for another image arises. Based on the photographic experiment by Jerry Chan, member of a group of blind people, this article aims at rethinking the photographic act as the real- life experience of an impression process, leading the blind apprentice photographer to experience sightedness within his very flesh.  

  7. Euro Banknote Recognition System for Blind People

    Directory of Open Access Journals (Sweden)

    Larisa Dunai Dunai

    2017-01-01

    Full Text Available This paper presents the development of a portable system with the aim of allowing blind people to detect and recognize Euro banknotes. The developed device is based on a Raspberry Pi electronic instrument and a Raspberry Pi camera, Pi NoIR (No Infrared filter dotted with additional infrared light, which is embedded into a pair of sunglasses that permit blind and visually impaired people to independently handle Euro banknotes, especially when receiving their cash back when shopping. The banknote detection is based on the modified Viola and Jones algorithms, while the banknote value recognition relies on the Speed Up Robust Features (SURF technique. The accuracies of banknote detection and banknote value recognition are 84% and 97.5%, respectively.

  8. Euro Banknote Recognition System for Blind People.

    Science.gov (United States)

    Dunai Dunai, Larisa; Chillarón Pérez, Mónica; Peris-Fajarnés, Guillermo; Lengua Lengua, Ismael

    2017-01-20

    This paper presents the development of a portable system with the aim of allowing blind people to detect and recognize Euro banknotes. The developed device is based on a Raspberry Pi electronic instrument and a Raspberry Pi camera, Pi NoIR (No Infrared filter) dotted with additional infrared light, which is embedded into a pair of sunglasses that permit blind and visually impaired people to independently handle Euro banknotes, especially when receiving their cash back when shopping. The banknote detection is based on the modified Viola and Jones algorithms, while the banknote value recognition relies on the Speed Up Robust Features (SURF) technique. The accuracies of banknote detection and banknote value recognition are 84% and 97.5%, respectively.

  9. Kalman filtering approach to blind equalization

    Science.gov (United States)

    Kutlu, Mehmet

    1993-12-01

    Digital communication systems suffer from the channel distortion problem which introduces errors due to intersymbol interference. The solution to this problem is provided by equalizers which use a training sequence to adapt to the channel. However in many cases in which a training sequence is unfeasible, the channel must be adapted blindly. Most of the blind equalization algorithms known so far have problems of convergence to local minima. Our intention is to offer an alternative approach by using extended Kalman filtering and hidden Markov models. They seem to yield more efficient algorithms which take the statistics of the transmitted sequence into consideration. The theoretical development of these new algorithms is discussed in this thesis. Also these algorithms have been simulated under different conditions. The results of simulations and comparisons with existing systems are provided. The models for simulations are presented as MATLAB codes.

  10. Emergence of Blind Areas in Information Spreading

    CERN Document Server

    Zhang, Zi-Ke; Han, Xiao-Pu; Liu, Chuang

    2013-01-01

    Recently, contagion-based (disease, information, etc.) spreading on social networks has been extensively studied. In this paper, other than traditional full interaction, we propose a partial interaction based spreading model, considering that the informed individuals would transmit information to only a certain fraction of their neighbors due to the transmission ability in real-world social networks. Simulation results on three representative networks (BA, ER, WS) indicate that the spreading efficiency is highly correlated with the network heterogeneity. In addition, a special phenomenon, namely \\emph{Information Blind Areas} where the network is separated by several information-unreachable clusters, will emerge from the spreading process. Furthermore, we also find that the size distribution of such information blind areas obeys power-law-like distribution, which has very similar exponent with that of site percolation. Detailed analyses show that the critical value is decreasing along with the network heterog...

  11. Permanent Cortical Blindness After Bronchial Artery Embolization

    Energy Technology Data Exchange (ETDEWEB)

    Doorn, Colette S. van, E-mail: cvandoorn@gmail.com; De Boo, Diederick W., E-mail: d.w.deboo@amc.uva.nl [Academic Medical Centre, Department of Radiology (Netherlands); Weersink, Els J. M., E-mail: e.j.m.weersink@amc.uva.nl [Academic Medical Centre, Department of Pulmonology (Netherlands); Delden, Otto M. van, E-mail: o.m.vandelden@amc.uva.nl; Reekers, Jim A., E-mail: j.a.reekers@amc.uva.nl; Lienden, Krijn P. van, E-mail: k.p.vanlienden@amc.uva.nl [Academic Medical Centre, Department of Radiology (Netherlands)

    2013-12-15

    A 35-year-old female with a known medical history of cystic fibrosis was admitted to our institution for massive hemoptysis. CTA depicted a hypertrophied bronchial artery to the right upper lobe and showed signs of recent bleeding at that location. Bronchial artery embolization (BAE) was performed with gelfoam slurry, because pronounced shunting to the pulmonary artery was present. Immediately after BAE, the patient developed bilateral cortical blindness. Control angiography showed an initially not opacified anastomosis between the embolized bronchial artery and the right subclavian artery, near to the origin of the right vertebral artery. Cessation of outflow in the bronchial circulation reversed the flow through the anastomosis and allowed for spill of embolization material into the posterior circulation. Unfortunately the cortical blindness presented was permanent.

  12. Sensing Structures Inspired by Blind Cave Fish

    Science.gov (United States)

    McConney, Michael E.; Chen, Nannan; Lu, David; Anderson, Kyle D.; Hu, Huan; Liu, Chang; Tsukruk, Vladimir V.

    2009-03-01

    Blind cave fish, with degenerated non-functioning eyes, have evolved to ``see'' their hydrodynamic environment by using the flow receptors of the lateral line system. The hair-cell receptors are encapsulated in a hydrogel-like material, called a cupula, which increases the sensitivity of the hair-cell receptors by coupling their motion to the surrounding flowing media. We characterized the viscoelastic properties and of blind cave fish cupulae by using colloidal-probe spectroscopy in fluid. A photo-patternable hydrogel with similar properties was developed to mimic the fish receptor coupling structure. Flow-based measurements indicated that the hydrogels enhance drag through increased surface area, but also inherent material properties. These bio-inspired structures endowed micro-fabricated flow sensors with sensitivities rivaling that of fish.

  13. Euro Banknote Recognition System for Blind People

    Science.gov (United States)

    Dunai Dunai, Larisa; Chillarón Pérez, Mónica; Peris-Fajarnés, Guillermo; Lengua Lengua, Ismael

    2017-01-01

    This paper presents the development of a portable system with the aim of allowing blind people to detect and recognize Euro banknotes. The developed device is based on a Raspberry Pi electronic instrument and a Raspberry Pi camera, Pi NoIR (No Infrared filter) dotted with additional infrared light, which is embedded into a pair of sunglasses that permit blind and visually impaired people to independently handle Euro banknotes, especially when receiving their cash back when shopping. The banknote detection is based on the modified Viola and Jones algorithms, while the banknote value recognition relies on the Speed Up Robust Features (SURF) technique. The accuracies of banknote detection and banknote value recognition are 84% and 97.5%, respectively. PMID:28117703

  14. Autobiographic narratives of congenital blind people

    Directory of Open Access Journals (Sweden)

    Maria Elisa Caputo Ferreira

    2009-12-01

    Full Text Available The research carried out in Juiz de Fora, MG, Brazil, intended at investigating, together with men and women who suffer from congenital visual impairment, how they felt about diversity, body image, self-esteem and vanity. The investigation of autobiographical accounts was the option for this study. Initially, 20 (twenty interviews were analyzed and 6 (six autobiographical accounts, selected from the peculiarities of each single interviewee – each one containing his/her single life lessons - followed suit. The conclusion reached is that the subjects had undergone an exhausting process of acceptance of their own impairment. If, on the one hand, the blindness comes with angst, uncertainties, and many difficulties, on the other hand, these circumstances lead the blind to face the ups and downs of life with courage, determination and will to live. Surprisingly, in the study the body was not approached at a source of concern or are which should be emphasized.

  15. Sociocultural theory and blind taste-tests

    Directory of Open Access Journals (Sweden)

    James Paul Gee

    2010-05-01

    Full Text Available In his entertaining 1986 book, The Real Coke, the Real Story, Thomas Oliver tells the story of the now infamous “New Coke”, a story retold in Malcolm Gladwell’s (2005 best-seller Blink. In the early 1980s, Pepsi began running commercials in which people took a sip from two glasses, not knowing which was Coke and which Pepsi. The majority preferred Pepsi. The Coca-Cola Company replicated these blind taste-tests and found the same result. Losing market share, Coke—long the dominant brand—changed its old formula and came out with “New Coke”, a soda made to a new formula, one that in a new round of blind taste-tests came out above Pepsi. But New Coke was a disaster.Consumers hated it. Coke not only returned to its old formula, but Pepsi never did overtake Coke, which remains today the dominant brand world-wide.

  16. Experimental Demonstration of Blind Quantum Computing

    CERN Document Server

    Barz, Stefanie; Broadbent, Anne; Fitzsimons, Joseph F; Zeilinger, Anton; Walther, Philip

    2011-01-01

    Quantum computers, besides offering substantial computational speedups, are also expected to provide the possibility of preserving the privacy of a computation. Here we show the first such experimental demonstration of blind quantum computation where the input, computation, and output all remain unknown to the computer. We exploit the conceptual framework of measurement-based quantum computation that enables a client to delegate a computation to a quantum server. We demonstrate various blind delegated computations, including one- and two-qubit gates and the Deutsch and Grover algorithms. Remarkably, the client only needs to be able to prepare and transmit individual photonic qubits. Our demonstration is crucial for future unconditionally secure quantum cloud computing and might become a key ingredient for real-life applications, especially when considering the challenges of making powerful quantum computers widely available.

  17. Blind integrity verification of medical images.

    Science.gov (United States)

    Huang, Hui; Coatrieux, Gouenou; Shu, Huazhong; Luo, Limin; Roux, Christian

    2012-11-01

    This work presents the first method of digital blind forensics within the medical imaging field with the objective to detect whether an image has been modified by some processing (e.g. filtering, lossy compression and so on). It compares two image features: the Histogram statistics of Reorganized Block-based Discrete cosine transform coefficients (HRBD), originally proposed for steganalysis purposes, and the Histogram statistics of Reorganized Block-based Tchebichef moments (HRBT). Both features serve as input of a set of SVM classifiers built in order to discriminate tampered images from original ones as well as to identify the nature of the global modification one image may have undergone. Performance evaluation, conducted in application to different medical image modalities, shows that these image features can help, independently or jointly, to blindly distinguish image processing or modifications with a detection rate greater than 70%. They also underline the complementarity of these features.

  18. Relearning to See in Cortical Blindness.

    Science.gov (United States)

    Melnick, Michael D; Tadin, Duje; Huxlin, Krystel R

    2016-04-01

    The incidence of cortically induced blindness is increasing as our population ages. The major cause of cortically induced blindness is stroke affecting the primary visual cortex. While the impact of this form of vision loss is devastating to quality of life, the development of principled, effective rehabilitation strategies for this condition lags far behind those used to treat motor stroke victims. Here we summarize recent developments in the still emerging field of visual restitution therapy, and compare the relative effectiveness of different approaches. We also draw insights into the properties of recovered vision, its limitations and likely neural substrates. We hope that these insights will guide future research and bring us closer to the goal of providing much-needed rehabilitation solutions for this patient population.

  19. Permanent cortical blindness after bronchial artery embolization.

    Science.gov (United States)

    van Doorn, Colette S; De Boo, Diederick W; Weersink, Els J M; van Delden, Otto M; Reekers, Jim A; van Lienden, Krijn P

    2013-12-01

    A 35-year-old female with a known medical history of cystic fibrosis was admitted to our institution for massive hemoptysis. CTA depicted a hypertrophied bronchial artery to the right upper lobe and showed signs of recent bleeding at that location. Bronchial artery embolization (BAE) was performed with gelfoam slurry, because pronounced shunting to the pulmonary artery was present. Immediately after BAE, the patient developed bilateral cortical blindness. Control angiography showed an initially not opacified anastomosis between the embolized bronchial artery and the right subclavian artery, near to the origin of the right vertebral artery. Cessation of outflow in the bronchial circulation reversed the flow through the anastomosis and allowed for spill of embolization material into the posterior circulation. Unfortunately the cortical blindness presented was permanent.

  20. The blind loop syndrome in children.

    Science.gov (United States)

    Stewart, B A; Karrer, F M; Hall, R J; Lilly, J R

    1990-08-01

    Anatomical abnormalities of the small bowel that cause intestinal stagnation result in bacterial overgrowth and a blind loop syndrome (BLS). Bacterial breakdown of bile salts and deamination of protein lead to malabsorption, steatorrhea, and fat-soluble vitamin deficiencies. Four children developed BLS as a complication of necrotizing enterocolitis, jejunal atresia, gastroschisis, and biliary atresia. BLS was suggested by abdominal pain, feculent vomiting, steatorrhea, and hypoalbuminemia. Dilated, stagnant bowel loops were demonstrated in each instance by upper gastrointestinal contrast study. Positive intestinal bacterial aspirates were confirmatory. Antibiotic treatment in two patients improved symptomatology but all children ultimately required surgery. Surgical procedures consisted of blind loop resection, intestinal plication, and catheterization of the bilioenteric conduit. All patients are now asymptomatic but one child suffers from parenteral nutrition-related cirrhosis and another requires chronic antibiotic therapy.

  1. Blind recognition of punctured convolutional codes

    Institute of Scientific and Technical Information of China (English)

    LU Peizhong; LI Shen; ZOU Yan; LUO Xiangyang

    2005-01-01

    This paper presents an algorithm for blind recognition of punctured convolutional codes which is an important problem in adaptive modulation and coding. For a given finite sequence of convolutional code, the parity check matrix of the convolutional code is first computed by solving a linear system with adequate error tolerance. Then a minimal basic encoding matrix of the original convolutional code and its puncturing pattern are determined according to the known parity check matrix of the punctured convolutional code.

  2. Ivermectin for onchocercal eye disease (river blindness)

    OpenAIRE

    Ejere, HO; Schwartz, E; Wormald, R; Evans, JR

    2012-01-01

    BACKGROUND: It is believed that ivermectin (a microfilaricide) could prevent blindness due to onchocerciasis. However, when given to everyone in communities where onchocerciasis is common, the effects of ivermectin on lesions affecting the eye are uncertain and data on whether the drug prevents visual loss are unclear. OBJECTIVES: The aim of this review was to assess the effectiveness of ivermectin in preventing visual impairment and visual field loss in onchocercal eye disease. The secondary...

  3. Application of Array Measurement in Blind Identification

    Institute of Scientific and Technical Information of China (English)

    王勇; 孙连明; 刘文江

    2003-01-01

    This paper deals with blind identification and deconvolution algorithm for an arbitrary, possibly white or colored, stationary or nonstationary signal, which is observed through array sensors. By using multiple sensors with their individual outputs sampled at a rate 1/T, one can obtain cyclostationary signals. They can be considered as a single-input multiple-output model with an identical but unknown input signal. With the array measurement, an algorithm for estimating the system transfer function model and its parameters is presented.

  4. BLIND NASAL INTUBATION IN CRANIOROFACIAL TRAUMA

    Directory of Open Access Journals (Sweden)

    K.R.DavidThakaran

    2013-09-01

    Full Text Available Restricted mouth opening presents one of the greatest challenges to the anesthetist for endotracheal intubation and ventilation. Awake blind nasal intubation has been one of the finest and favored techniques for intubation in previous decades for restricted mouth opening patients. A coordinated team approach, monitoring and adequate counseling of the patient is mandatory for the airway management to carry out a safe surgical procedure

  5. Transient cortical blindness after coronary artery angiography.

    Science.gov (United States)

    Terlecki, Michał; Wojciechowska, Wiktoria; Rajzer, Marek; Jurczyszyn, Artur; Bazan-Socha, Stanisława; Bryniarski, Leszek; Czarnecka, Danuta

    2013-01-01

    Coronary angiography is the current gold standard for the diagnosis of ischemic heart disease and therefore the prevalence of percutaneous coronary procedures such as angiography and angioplasty is high. The occurrence of cerebral complications after coronary angiography and coronary angioplasty is low and it mainly includes transient ischemic attack and stroke. The prevalence of transient cortical blindness after X-ray contrast media is low and it is usually seen after cerebral angiography. Until now only a few cases of transient cortical blindness have been described after coronary artery angiography. Regarding the spread of coronary angiography worldwide and in Poland this complication is uniquely rare. A 32-year-old man with multiple extrasystolic ventricular arrhythmia suggesting Brugada syndrome diagnosis according to morphology of the left bundle branch block and with decreased left ventricular ejection fraction was admitted to the First Department of Cardiology and Hypertension, Medical College of the Jagiellonian University in Krakow. Coronary angiography was performed in order to exclude ischemic etiology of the observed abnormalities. No arteriosclerotic lesions were found in coronary arteries. Transient cortical blindness was observed directly after angiography which may have been caused by the neurotoxic effect of the used X-ray contrast medium. In ophthalmologic and neurologic examination as well as in the cerebral computed tomography scan no pathologies were found. Visual impairment disappeared totally within several hours.

  6. IMPROVED COVARIANCE DRIVEN BLIND SUBSPACE IDENTIFICATION METHOD

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhiyi; FAN Jiangling; HUA Hongxing

    2006-01-01

    An improved covariance driven subspace identification method is presented to identify the weakly excited modes. In this method, the traditional Hankel matrix is replaced by a reformed one to enhance the identifiability of weak characteristics. The robustness of eigenparameter estimation to noise contamination is reinforced by the improved Hankel matrix. In combination with component energy index (CEI) which indicates the vibration intensity of signal components, an alternative stabilization diagram is adopted to effectively separate spurious and physical modes. Simulation of a vibration system of multiple-degree-of-freedom and experiment of a frame structure subject to wind excitation are presented to demonstrate the improvement of the proposed blind method. The performance of this blind method is assessed in terms of its capability in extracting the weak modes as well as the accuracy of estimated parameters. The results have shown that the proposed blind method gives a better estimation of the weak modes from response signals of small signal to noise ratio (SNR)and gives a reliable separation of spurious and physical estimates.

  7. The spatiotopic 'visual' cortex of the blind

    Science.gov (United States)

    Likova, Lora

    2012-03-01

    Visual cortex activity in the blind has been shown in sensory tasks. Can it be activated in memory tasks? If so, are inherent features of its organization meaningfully employed? Our recent results in short-term blindfolded subjects imply that human primary visual cortex (V1) may operate as a modality-independent 'sketchpad' for working memory (Likova, 2010a). Interestingly, the spread of the V1 activation approximately corresponded to the spatial extent of the images in terms of their angle of projection to the subject. We now raise the questions of whether under long-term visual deprivation V1 is also employed in non-visual memory task, in particular in congenitally blind individuals, who have never had visual stimulation to guide the development of the visual area organization, and whether such spatial organization is still valid for the same paradigm that was used in blindfolded individuals. The outcome has implications for an emerging reconceptualization of the principles of brain architecture and its reorganization under sensory deprivation. Methods: We used a novel fMRI drawing paradigm in congenitally and late-onset blind, compared with sighted and blindfolded subjects in three conditions of 20s duration, separated by 20s rest-intervals, (i) Tactile Exploration: raised-line images explored and memorized; (ii) Tactile Memory Drawing: drawing the explored image from memory; (iii) Scribble: mindless drawing movements with no memory component. Results and Conclusions: V1 was strongly activated for Tactile Memory Drawing and Tactile Exploration in these totally blind subjects. Remarkably, after training, even in the memory task, the mapping of V1 activation largely corresponded to the angular projection of the tactile stimuli relative to the ego-center (i.e., the effective visual angle at the head); beyond this projective boundary, peripheral V1 signals were dramatically reduced or even suppressed. The matching extent of the activation in the congenitally blind

  8. Diagnostic value of 3 D CT surface reconstruction in spinal fractures

    Energy Technology Data Exchange (ETDEWEB)

    Koesling, S. [Department of Radiology, Univ. of Leipzig (Germany); Dietrich, K. [Department of Radiology, Univ. of Leipzig (Germany); Steinecke, R. [Department of Radiology, Univ. of Leipzig (Germany); Kloeppel, R. [Department of Radiology, Univ. of Leipzig (Germany); Schulz, H.G. [Department of Radiology, Univ. of Leipzig (Germany)

    1997-02-01

    Our purpose was to evaluate the diagnostic value of three-dimensional (3 D) CT surface reconstruction in spinal fractures in comparison with axial and reformatted images. A total of 50 patients with different CT-proven spinal fractures were analysed retrospectively. Based on axial scans and reformatted images, the spinal fractures were classified according to several classifications as Magerl for the thoraco-lumbar and lower cervical spine by one radiologist. Another radiologist performed 3 D CT surface reconstructions with the aim of characterizing the different types of spinal fractures. A third radiologist classified the 3 D CT surface reconstruction according to the Magerl classification. The results of the blinded reading process were compared. It was checked to see in which type and subgroup 3 D surface reconstructions were helpful. Readers one and two obtained the same results in the classification. The 3 D surface reconstruction did not yield any additional diagnostic information concerning type A and B injuries. Indeed, the full extent of the fracture could be easier recognized with axial and reformatted images in all cases. In 10 cases of C injuries, the dislocation of parts of vertebrae could be better recognized with the help of 3 D reconstructions. A 3 D CT surface reconstruction is only useful in rotational and shear vertebral injuries (Magerl type C injury). (orig.). With 4 figs., 1 tab.

  9. Blindness and the age of enlightenment: Diderot's letter on the blind.

    Science.gov (United States)

    Margo, Curtis E; Harman, Lynn E; Smith, Don B

    2013-01-01

    Several months after anonymously publishing an essay in 1749 with the title "Letter on the Blind for the Use of Those Who Can See," the chief editor of the French Encyclopédie was arrested and taken to the prison fortress of Vincennes just east of Paris, France. The correctly assumed author, Denis Diderot, was 35 years old and had not yet left his imprint on the Age of Enlightenment. His letter, which recounted the life of Nicolas Saunderson, a blind mathematician, was intended to advance secular empiricism and disparage the religiously tinged rationalism put forward by Rene Descartes. The letter's discussion of sensory perception in men born blind dismissed the supposed primacy of visual imagery in abstract thinking. The essay did little to resolve any philosophical controversy, but it marked a turning point in Western attitudes toward visual disability.

  10. The sensory construction of dreams and nightmare frequency in congenitally blind and late blind individuals

    DEFF Research Database (Denmark)

    Meaidi, Amani; Jennum, Poul; Ptito, Maurice

    2014-01-01

    . Every morning participants filled in a questionnaire related to the sensory construction of the dream, its emotional and thematic content, and the possible occurrence of nightmares. We also assessed participants' ability of visual imagery during waking cognition, sleep quality, and depression...... and anxiety levels. RESULTS: All blind participants had fewer visual dream impressions compared to SC participants. In LB participants, duration of blindness was negatively correlated with duration, clarity, and color content of visual dream impressions. CB participants reported more auditory, tactile......, gustatory, and olfactory dream components compared to SC participants. In contrast, LB participants only reported more tactile dream impressions. Blind and SC participants did not differ with respect to emotional and thematic dream content. However, CB participants reported more aggressive interactions...

  11. Attack and improvements of fair quantum blind signature schemes

    Science.gov (United States)

    Zou, Xiangfu; Qiu, Daowen

    2013-06-01

    Blind signature schemes allow users to obtain the signature of a message while the signer learns neither the message nor the resulting signature. Therefore, blind signatures have been used to realize cryptographic protocols providing the anonymity of some participants, such as: secure electronic payment systems and electronic voting systems. A fair blind signature is a form of blind signature which the anonymity could be removed with the help of a trusted entity, when this is required for legal reasons. Recently, a fair quantum blind signature scheme was proposed and thought to be safe. In this paper, we first point out that there exists a new attack on fair quantum blind signature schemes. The attack shows that, if any sender has intercepted any valid signature, he (she) can counterfeit a valid signature for any message and can not be traced by the counterfeited blind signature. Then, we construct a fair quantum blind signature scheme by improved the existed one. The proposed fair quantum blind signature scheme can resist the preceding attack. Furthermore, we demonstrate the security of the proposed fair quantum blind signature scheme and compare it with the other one.

  12. Reconstruction in Fourier space

    Science.gov (United States)

    Burden, A.; Percival, W. J.; Howlett, C.

    2015-10-01

    We present a fast iterative fast Fourier transform (FFT) based reconstruction algorithm that allows for non-parallel redshift-space distortions (RSDs). We test our algorithm on both N-body dark matter simulations and mock distributions of galaxies designed to replicate galaxy survey conditions. We compare solenoidal and irrotational components of the redshift distortion and show that an approximation of this distortion leads to a better estimate of the real-space potential (and therefore faster convergence) than ignoring the RSD when estimating the displacement field. Our iterative reconstruction scheme converges in two iterations for the mock samples corresponding to Baryon Oscillation Spectroscopic Survey CMASS Data Release 11 when we start with an approximation of the RSD. The scheme takes six iterations when the initial estimate, measured from the redshift-space overdensity, has no RSD correction. Slower convergence would be expected for surveys covering a larger angle on the sky. We show that this FFT based method provides a better estimate of the real-space displacement field than a configuration space method that uses finite difference routines to compute the potential for the same grid resolution. Finally, we show that a lognormal transform of the overdensity, used as a proxy for the linear overdensity, is beneficial in estimating the full displacement field from a dense sample of tracers. However, the lognormal transform of the overdensity does not perform well when estimating the displacements from sparser simulations with a more realistic galaxy density.

  13. LHCb; LHCb Jet Reconstruction

    CERN Multimedia

    Augusto, O

    2012-01-01

    The Large Hadron Collider (LHC) is the most powerful particle accelerator in the world. It has been designed to collide proton beams at an energy up to 14 TeV in the center of mass. In 2011, the data taking was done with a center of mass energy of 7 TeV, the instant luminosity has reached values greater than $4 \\times 10^{32} cm^{-2} s^{-1}$ and the integrated luminosity reached the value of 1.02 $fb^{-1}$ on the LHCb. The jet reconstruction is fundamental to observe events that can be used to test pertubative QCD (pQCD). It also provides a way to observe standard model channels and searches for new physics like SUSY. The anti-kt algorithm is a jet reconstruction algorithm that is based on the distance of the particles on the space $\\eta \\times \\phi$ and on the transverse momentum of particles. To maximize the energy resolution all information about the trackers and the calo...

  14. Reconstructing Experiences through Sketching

    CERN Document Server

    Karapanos, Evangelos; Hassenzahl, Marc

    2009-01-01

    This paper presents iScale, a survey tool that aims at eliciting users' experiences with a product from memory. iScale employs sketching in imposing a process in the reconstruction of one's experiences. Two versions of iScale, the Constructive and the Value-Account iScale, were motivated by two distinct theories on how people reconstruct emotional experiences from memory. These two versions were tested in two separate studies. Study 1 aimed at providing qualitative insight into the use of iScale and compared its performance to that of free-hand sketching. Study 2 compared the two iScale versions to a control condition: that of reporting one's experiences without employing any form of sketching. Significant differences between iScale and the "no-sketching" tool were found. Overall, iScale resulted in a) an increase in the number of experience reports that subjects provided, b) an increase in the amount of contextual information for the reported experiences, and c) an increase in subjects' accuracy in recalling...

  15. Biomaterials for craniofacial reconstruction

    Directory of Open Access Journals (Sweden)

    Neumann, Andreas

    2009-01-01

    Full Text Available Biomaterials for reconstruction of bony defects of the skull comprise of osteosynthetic materials applied after osteotomies or traumatic fractures and materials to fill bony defects which result from malformation, trauma or tumor resections. Other applications concern functional augmentations for dental implants or aesthetic augmentations in the facial region.For ostheosynthesis, mini- and microplates made from titanium alloys provide major advantages concerning biocompatibility, stability and individual fitting to the implant bed. The necessity of removing asymptomatic plates and screws after fracture healing is still a controversial issue. Risks and costs of secondary surgery for removal face a low rate of complications (due to corrosion products when the material remains in situ. Resorbable osteosynthesis systems have similar mechanical stability and are especially useful in the growing skull.The huge variety of biomaterials for the reconstruction of bony defects makes it difficult to decide which material is adequate for which indication and for which site. The optimal biomaterial that meets every requirement (e.g. biocompatibility, stability, intraoperative fitting, product safety, low costs etc. does not exist. The different material types are (autogenic bone and many alloplastics such as metals (mainly titanium, ceramics, plastics and composites. Future developments aim to improve physical and biological properties, especially regarding surface interactions. To date, tissue engineered bone is far from routine clinical application.

  16. Virtual 3-D Facial Reconstruction

    Directory of Open Access Journals (Sweden)

    Martin Paul Evison

    2000-06-01

    Full Text Available Facial reconstructions in archaeology allow empathy with people who lived in the past and enjoy considerable popularity with the public. It is a common misconception that facial reconstruction will produce an exact likeness; a resemblance is the best that can be hoped for. Research at Sheffield University is aimed at the development of a computer system for facial reconstruction that will be accurate, rapid, repeatable, accessible and flexible. This research is described and prototypical 3-D facial reconstructions are presented. Interpolation models simulating obesity, ageing and ethnic affiliation are also described. Some strengths and weaknesses in the models, and their potential for application in archaeology are discussed.

  17. Exercises in PET Image Reconstruction

    Science.gov (United States)

    Nix, Oliver

    These exercises are complementary to the theoretical lectures about positron emission tomography (PET) image reconstruction. They aim at providing some hands on experience in PET image reconstruction and focus on demonstrating the different data preprocessing steps and reconstruction algorithms needed to obtain high quality PET images. Normalisation, geometric-, attenuation- and scatter correction are introduced. To explain the necessity of those some basics about PET scanner hardware, data acquisition and organisation are reviewed. During the course the students use a software application based on the STIR (software for tomographic image reconstruction) library 1,2 which allows them to dynamically select or deselect corrections and reconstruction methods as well as to modify their most important parameters. Following the guided tutorial, the students get an impression on the effect the individual data precorrections have on image quality and what happens if they are forgotten. Several data sets in sinogram format are provided, such as line source data, Jaszczak phantom data sets with high and low statistics and NEMA whole body phantom data. The two most frequently used reconstruction algorithms in PET image reconstruction, filtered back projection (FBP) and the iterative OSEM (ordered subset expectation maximation) approach are used to reconstruct images. The exercise should help the students gaining an understanding what the reasons for inferior image quality and artefacts are and how to improve quality by a clever choice of reconstruction parameters.

  18. Untraceable partially blind signature based on DLOG problem

    Institute of Scientific and Technical Information of China (English)

    黄征; 陈克非; 冠卫东

    2004-01-01

    This paper proposes a new untraceable Partially Blind Signature scheme which is a cross between the traditional signature scheme and the blind signature scheme. In this proposed scheme, the message M that the signer signed can be divided into two parts. The first part can be known to the signer (like that in the traditional signature scheme) while the other part cannot be known to the signer (like that in the blind signature scheme). After having signed M, the signer cannot determine if he has made the signature of M except through the part that he knows. We draw ideas from Brands' "Restricted Blind Signature" to solve the Untraceable Partially Blind Signature problem. Our scheme is a probabilistic signature scheme and the security of our Untraceable Partially Blind Signature scheme relies on the difficulty of computing discrete logarithm.

  19. A NEW EFFICIENT ID-BASED PROXY BLIND SIGNATURE SCHEME

    Institute of Scientific and Technical Information of China (English)

    Ming Yang; Wang Yumin

    2008-01-01

    In a proxy blind signature scheme, the proxy signer is allowed to generate a blind signature on behalf of the original signer. The proxy blind signature scheme is useful in several applications such as e-voting, e-payment, etc. Recently, Zheng, et al. presented an IDentity (ID)-based proxy blind signature. In this paper, a new efficient ID-based proxy blind signature scheme from bilinear pairings is proposed, which can satisfy the security properties of both the proxy signatures and the blind signature schemes. Analysis of the scheme efficiency shows that the new scheme is more efficient than Zheng, et al.'s scheme. The proposed scheme is more practical in the real world.

  20. Enhanced chemosensory detection of negative emotions in congenital blindness

    DEFF Research Database (Denmark)

    Iversen, Katrine D.; Ptito, Maurice; Møller, Per;

    2015-01-01

    blind and normal sighted individuals in their ability to discriminate and identify emotions from body odours. A group of 14 congenitally blind and 14 age- and sex-matched sighted control subjects participated in the study. We compared participants' abilities to detect and identify by smelling sweat from...... donors who had been watching excerpts from emotional movies showing amusement, fear, disgust, or sexual arousal. Our results show that congenitally blind subjects outperformed sighted controls in identifying fear from male donors. In addition, there was a strong tendency that blind individuals were also...... better in detecting disgust. Our findings reveal that congenitally blind individuals are better at identifying ecologically important emotions and provide new insights into the mechanisms of social and affective communication in blindness....

  1. PARENT Quick Blind Round-Robin Test Report

    Energy Technology Data Exchange (ETDEWEB)

    Braatz, Brett G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Heasler, Patrick G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Meyer, Ryan M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-09-30

    The U.S. Nuclear Regulatory Commission has established the Program to Assess the Reliability of Emerging Nondestructive Techniques (PARENT) whose goal is to investigate the effectiveness of current and novel nondestructive examination procedures and techniques to find flaws in nickel-alloy welds and base materials. This is to be done by conducting a series of open and blind international round-robin tests on a set of piping components that include large-bore dissimilar metal welds, small-bore dissimilar metal welds, and bottom-mounted instrumentation penetration welds. The blind testing is being conducted in two segments, one is called Quick-Blind and the other is called Blind. The Quick-Blind testing and destructive analysis of the test blocks has been completed. This report describes the four Quick-Blind test blocks used, summarizes their destructive analysis, gives an overview of the nondestructive evaluation (NDE) techniques applied, provides an analysis inspection data, and presents the conclusions drawn.

  2. Ocular Surface Reconstruction: Recent Innovations

    Directory of Open Access Journals (Sweden)

    Madhavan HN

    2009-01-01

    Full Text Available The ocular surface is exceptionally rich in complexity and functionality. Severe ocular surface disorders/conditions, such as chemical or thermal injuries, Stevens-Johnson syndrome (SJS, ocular cicatricial pemphigoid, neurotrophic keratopathy, chronic limbitis, and severe microbial keratitis cause significant morbidities and even corneal blindness. Hypofunction may be caused by Aniridia, Neurotrophy, Endocrine, Pterygium and Chronic limbitis Approximately 6000 patients are seen in Ocular Surface Clinic every year; almost 80% have some form of dry eyes. About 125 new patients of Stevens Johnson Syndrome are seen in a year of which approximately 25% may benefit from Cultured Epithelial Transplant and 75 new patients of thermal/chemical injury in a year of which almost 80% will benefit from Stem Cell Transplantation. Of the 128 severe vernal keratoconjunctivitis which were seen in the ocular surface clinic, 10% require stem cell transplantation. Nearly 30 new cases of Ocular cicatrical pemphigoid every year are seen and they may need stem cell transplantation. In addition, several patients with persistent epithelial defects may benefit from limbal stem cell transplantation to alleviate, maintain conjunctivalization regression and corneal avascularity limbal deficiency, and restore vision. Even if granted that this statistics is for a single large ophthalmic hospital, for a large country as India with 1.1 billion populations, the number of patients requiring corneal stem cell transplantation is enormous. Stem cells in the palisades of Vogt participate in regeneration and preservation of corneal transparency and avascularity. The diminished regenerative capacity seen in LSCD is characterized by persistent epithelial defects, erosion and ulceration, conjunctivalization and neovascularization, and chronic inflammation. Standard corneal transplantation for restoration of corneal clarity and avascularity is a contraindication in the surgical management

  3. The global cost of eliminating avoidable blindness

    Directory of Open Access Journals (Sweden)

    Kirsten L Armstrong

    2012-01-01

    Full Text Available Aims : To complete an initial estimate of the global cost of eliminating avoidable blindness, including the investment required to build ongoing primary and secondary health care systems, as well as to eliminate the ′backlog′ of avoidable blindness. This analysis also seeks to understand and articulate where key data limitations lie. Materials and Methods : Data were collected in line with a global estimation approach, including separate costing frameworks for the primary and secondary care sectors, and the treatment of backlog. Results : The global direct health cost to eliminate avoidable blindness over a 10-year period from 2011 to 2020 is estimated at $632 billion per year (2009 US$. As countries already spend $592 billion per annum on eye health, this represents additional investment of $397.8 billion over 10 years, which is $40 billion per year or $5.80 per person for each year between 2010 and 2020. This is concentrated in high-income nations, which require 68% of the investment but comprise 16% of the world′s inhabitants. For all other regions, the additional investment required is $127 billion. Conclusions : This costing estimate has identified that low- and middle-income countries require less than half the additional investment compared with high-income nations. Low- and middle-income countries comprise the greater investment proportion in secondary care whereas high-income countries require the majority of investment into the primary sector. However, there is a need to improve sector data. Investment in better data will have positive flow-on effects for the eye health sector.

  4. Nonlinear Blind Equalization for Volume Holographic Data Storage

    Institute of Scientific and Technical Information of China (English)

    商未雄; 何庆声; 金国藩

    2004-01-01

    We investigate the nonlinear blind equalization for volume holographic data storage channel. Base on the recurrent neural network channel model, we describe a novel blind equalizer for the volume holographic data storage system to improve the bit error rate and hence to make the storage densities achievable. The experimental results also indicate that a significant improvement in the bit error rate to 2.55 × 10-3 is possible with the nonlinear blind equalization.

  5. ITERATIVE MULTICHANNEL BLIND DECONVOLUTION METHOD FOR TEMPORALLY COLORED SOURCES

    Institute of Scientific and Technical Information of China (English)

    Zhang Mingjian; Wei Gang

    2004-01-01

    An iterative separation approach, i.e. source signals are extracted and removed one by one, is proposed for multichannel blind deconvolution of colored signals. Each source signal is extracted in two stages: a filtered version of the source signal is first obtained by solving the generalized eigenvalue problem, which is then followed by a single channel blind deconvolution based on ensemble learning. Simulation demonstrates the capability of the approach to perform efficient mutichannel blind deconvolution.

  6. Information on blinding in registered records of clinical trials

    Directory of Open Access Journals (Sweden)

    Viergever Roderik F

    2012-11-01

    Full Text Available Abstract Information on blinding is part of the data that should be provided upon registration of a trial at a clinical trials registry. Reporting of blinding is often absent or of low quality in published articles of clinical trials. This study researched the presence and quality of information on blinding in registered records of clinical trials and highlights the important role of data-recording formats at clinical trial registries in ensuring high-quality registration.

  7. Enhanced chemosensory detection of negative emotions in congenital blindness

    DEFF Research Database (Denmark)

    Iversen, Katrine D.; Ptito, Maurice; Møller, Per

    2015-01-01

    It is generally acknowledged that congenitally blind individuals develop superior sensory abilities in order to compensate for their lack of vision. Substantial research has been done on somatosensory and auditory sensory information processing of the blind. However, relatively little information...... is available about compensatory plasticity in the olfactory domain. Although previous studies indicate that blind individuals have superior olfactory abilities, no studies so far have investigated their sense of smell in relation to social and affective communication. The current study compares congenitally...

  8. Transient cortical blindness post angiography--a case report.

    Science.gov (United States)

    Clarke, T R; Johnson, P; Webster, D; Gilbert, D T; Barton, E N

    2011-06-01

    A 56-year old female reported having had a fall two weeks prior to presentation. Computed Tomography (CT) scan showed an acute right-sided convexity subdural haematoma. A computed tomography angiogram revealed no vascular anomaly. One hour post procedure she had bilateral cortical blindness. Her vision subsequently was fully restored. A diagnosis of transient cortical blindness was made. Transient cortical blindness is a rare but recognized complication ofintra-arterial injection of iodinated contrast agents.

  9. Schizophrenia and cortical blindness: protective effects and implications for language

    OpenAIRE

    Leivada, Evelina; Boeckx, Cedric

    2014-01-01

    The repeatedly noted absence of case-reports of individuals with schizophrenia and congenital/early developed blindness has led several authors to argue that the latter can confer protective effects against the former. In this work, we present a number of relevant case-reports from different syndromes that show comorbidity of congenital and early blindness with schizophrenia. On the basis of these reports, we argue that a distinction between different types of blindness in terms of the origin...

  10. Recurrent Bilateral Occipital Infarct with Cortical Blindness and Anton Syndrome

    OpenAIRE

    Kiu Kwong Yew; Sanihah Abdul halim; Ahmad Tajudin Liza-Sharmini; John Tharakan

    2014-01-01

    Bilateral cortical blindness and Anton syndrome, are most commonly caused by ischaemic stroke. In this condition, patients have loss of vision but deny their blindness despite objective evidence of visual loss. We report a case of a patient with multiple cardiovascular risk factors who developed recurrent bilateral occipital lobe infarct with Anton syndrome. A suspicion of this condition should be raised when the patient has denial of blindness in the presence of clinical and radiological evi...

  11. Schizophrenia and cortical blindness: Protective effects and implications for language

    OpenAIRE

    Evelina eLeivada; Cedric eBoeckx

    2014-01-01

    The repeatedly noted absence of case-reports of individuals with schizophrenia and congenital/early developed blindness has led several authors to argue that the latter can confer protective effects against the former. In this work, we present a number of relevant case-reports from different syndromes that show comorbidity of congenital and early blindness with schizophrenia. On the basis of these reports, we argue that a distinction between different types of blindness in terms of the origin...

  12. Blind Search for Variability in Planck Data

    CERN Document Server

    Rachen, Jörg P; Reinecke, Martin

    2015-01-01

    The sky is full of variable and transient sources on all time scales, from milliseconds to decades. Planck's regular scanning strategy makes it an ideal instrument to search for variable sky signals in the millimetre and submillimetre regime, on time scales from hours to several years. A precondition is that instrumental noise and systematic effects, caused in particular by non-symmetric beam shapes, are properly removed. We present a method to perform a full sky blind search for variable and transient objects at all Planck frequencies.

  13. The chemistry of John Dalton's color blindness.

    Science.gov (United States)

    Hunt, D M; Dulai, K S; Bowmaker, J K; Mollon, J D

    1995-02-17

    John Dalton described his own color blindness in 1794. In common with his brother, he confused scarlet with green and pink with blue. Dalton supposed that his vitreous humor was tinted blue, selectively absorbing longer wavelengths. He instructed that his eyes should be examined after his death, but the examination revealed that the humors were perfectly clear. In experiments presented here, DNA extracted from his preserved eye tissue showed that Dalton was a deuteranope, lacking the middlewave photopigment of the retina. This diagnosis is shown to be compatible with the historical record of his phenotype, although it contradicts Thomas Young's belief that Dalton was a protanope.

  14. Cryptanalysis of fair quantum blind signatures

    Institute of Scientific and Technical Information of China (English)

    He Li-Bao; Huang Liu-Sheng; Yang Wei; Xu Rui

    2012-01-01

    We investigate the fair quantum blind signature scheme proposed by Wang and Wen [Wang T Y and Wen Q Y 2010 Chin.Phys.B 19 060307],which uses the fundamental properties of quantum mechanics and the availability of a trusted arbitrator.However,in this paper,we find that the protocol cannot satisfy the property of non-forgeability even under the condition that the trusted arbitrator is totally credible.Moreover,a simple feasible suggestion for improving the protocol is proposed.

  15. Computer Game Lugram - Version for Blind Children

    Directory of Open Access Journals (Sweden)

    V. Delić

    2011-06-01

    Full Text Available Computer games have undoubtedly become an integral part of educational activities of children. However, since computer games typically abound with audio and visual effects, most of them are completely useless for children with disabilities. Specifically, computer games dealing with the basics of geometry can contribute to mathematics education, but they require significant modifications in order to be suitable for the visually impaired children. The paper presents the results of research and adaptation of the educational computer game Lugram to the needs of completely blind children, as well as the testing of the prototype, whose results are encouraging to further research and development in the same direction.

  16. Grading learning for blind source separation

    Institute of Scientific and Technical Information of China (English)

    张贤达; 朱孝龙; 保铮

    2003-01-01

    By generalizing the learning rate parameter to a learning rate matrix, this paper proposes agrading learning algorithm for blind source separation. The whole learning process is divided into threestages: initial stage, capturing stage and tracking stage. In different stages, different learning rates areused for each output component, which is determined by its dependency on other output components. Itis shown that the grading learning algorithm is equivariant and can keep the separating matrix from be-coming singular. Simulations show that the proposed algorithm can achieve faster convergence, bettersteady-state performance and higher numerical robustness, as compared with the existing algorithmsusing fixed, time-descending and adaptive learning rates.

  17. Extrapontine myelinolysis resulting in transient cortical blindness.

    Science.gov (United States)

    Langer, Jennifer E; Wilson, William G; Raghavan, Prashant; Rust, Robert S; Goodkin, Howard P

    2010-02-01

    Central pontine myelinolysis and extrapontine myelinolysis are characterized by symmetric demyelination subsequent to rapid shifts in serum osmolality. Described here is a novel case of transient cortical blindness in association with imaging features of extrapontine myelinolysis, which occurred in a child with carbamoyl phosphate synthetase deficiency after rapid correction of hyperammonemia. Serum sodium levels were within normal limits at presentation and throughout the period of ammonia correction. A potential pathogenic mechanism of osmotic demyelination in the setting of acute treatment for hyperammonemia in a patient with a urea cycle abnormality includes disruption of the blood-brain barrier and re-equilibration of organic osmolytes, particularly glutamine.

  18. Hypersensitivity to pain in congenital blindness

    DEFF Research Database (Denmark)

    Slimani, Hocine; Danti, Sabrina; Ricciardi, Emiliano

    2013-01-01

    Vision is important for avoiding encounters with objects in the environment that may imperil physical integrity. We tested whether, in the absence of vision, a lower pain threshold would arise from an adaptive shift to other sensory channels. We therefore measured heat and cold pain thresholds...... and responses to suprathreshold heat stimuli in 2 groups of congenitally blind and matched normal-sighted participants. We also assessed detection thresholds for innocuous warmth and cold, and participants' attitude toward painful encounters in daily life. Our results show that, compared to sighted subjects...

  19. Biomatrices for bladder reconstruction.

    Science.gov (United States)

    Lin, Hsueh-Kung; Madihally, Sundar V; Palmer, Blake; Frimberger, Dominic; Fung, Kar-Ming; Kropp, Bradley P

    2015-03-01

    There is a demand for tissue engineering of the bladder needed by patients who experience a neurogenic bladder or idiopathic detrusor overactivity. To avoid complications from augmentation cystoplasty, the field of tissue engineering seeks optimal scaffolds for bladder reconstruction. Naturally derived biomaterials as well as synthetic and natural polymers have been explored as bladder substitutes. To improve regenerative properties, these biomaterials have been conjugated with functional molecules, combined with nanotechology, or seeded with exogenous cells. Although most studies reported complete and functional bladder regeneration in small-animal models, results from large-animal models and human clinical trials varied. For functional bladder regeneration, procedures for biomaterial fabrication, incorporation of biologically active agents, introduction of nanotechnology, and application of stem-cell technology need to be standardized. Advanced molecular and medical technologies such as next generation sequencing and magnetic resonance imaging can be introduced for mechanistic understanding and non-invasive monitoring of regeneration processes, respectively.

  20. Reconstructability analysis of epistasis.

    Science.gov (United States)

    Zwick, Martin

    2011-01-01

    The literature on epistasis describes various methods to detect epistatic interactions and to classify different types of epistasis. Reconstructability analysis (RA) has recently been used to detect epistasis in genomic data. This paper shows that RA offers a classification of types of epistasis at three levels of resolution (variable-based models without loops, variable-based models with loops, state-based models). These types can be defined by the simplest RA structures that model the data without information loss; a more detailed classification can be defined by the information content of multiple candidate structures. The RA classification can be augmented with structures from related graphical modeling approaches. RA can analyze epistatic interactions involving an arbitrary number of genes or SNPs and constitutes a flexible and effective methodology for genomic analysis.

  1. CRUCIATE LIGAMENT RECONSTRUCTION

    Directory of Open Access Journals (Sweden)

    A. V. Korolev

    2016-01-01

    Full Text Available Purpose: To evaluate long-term results of meniscal repair during arthroscopic ACL reconstruction.Materials and methods: 45 patients who underwent meniscal repair during arthroscopic ACL reconstruction between 2007 and 2013 by the same surgeon were included in the study. In total, fifty meniscus were repaired (26 medial and 24 lateral. Procedures included use of one up to four Fast-Fix implants (Smith & Nephew. In five cases both medial and lateral meniscus were repaired. Cincinnati, IKDC and Lysholm scales were used for long-term outcome analysis.Results: 19 male and 26 female patients were included in the study aging from 15 to 59 years (mean age 33,2±1,5. Median time from injury to surgical procedure was zero months (ranging zero to one. Mean time from surgery to scale analysis was 55,9±3 months (ranged 20-102. Median Cincinnati score was 97 (ranged 90-100, with excellent results in 93% of cases (43 patients and good results in 7% (3 patients. Median IKDC score was 90,8 (ranged 86,2-95,4, with excellent outcomes in 51% of cases (23 patients, good in 33% (15 patients and satisfactory in 16% (7 patients. Median Lysholm score was 95 (ranged 90-100, with excellent outcomes in 76% of cases (34 patients and good in 24% (11 patients. Authors identified no statistical differences when comparing survey results in age, sex and time from trauma to surgery.Conclusions: Results of the present study match the data from orthopedic literature that prove meniscal repair as a safe and efficient procedure with good and excellent outcomes. All-inside meniscal repair can be used irrespectively of patients' age and is efficient even in case of delayed procedures.

  2. Color-Blind Racism, Color-Blind Theology, and Church Practices

    Science.gov (United States)

    Hearn, Mark

    2009-01-01

    Color-blind racism develops when persons ignore color in people and see them simply as individuals. As persons of color in racialized societies such as the United States are unequally treated on account of their color, the issue becomes a matter of faith and religious experience as religious leaders and educators, who disregard color, overlook…

  3. A Smart Infrared Microcontroller-Based Blind Guidance System

    Directory of Open Access Journals (Sweden)

    Amjed S. Al-Fahoum

    2013-01-01

    Full Text Available Blindness is a state of lacking the visual perception due to physiological or neurological factors. The partial blindness represents the lack of integration in the growth of the optic nerve or visual centre of the eye, and total blindness is the full absence of the visual light perception. In this work, a simple, cheap, friendly user, smart blind guidance system is designed and implemented to improve the mobility of both blind and visually impaired people in a specific area. The proposed work includes a wearable equipment consists of head hat and mini hand stick to help the blind person to navigate alone safely and to avoid any obstacles that may be encountered, whether fixed or mobile, to prevent any possible accident. The main component of this system is the infrared sensor which is used to scan a predetermined area around blind by emitting-reflecting waves. The reflected signals received from the barrier objects are used as inputs to PIC microcontroller. The microcontroller is then used to determine the direction and distance of the objects around the blind. It also controls the peripheral components that alert the user about obstacle's shape, material, and direction. The implemented system is cheap, fast, and easy to use and an innovative affordable solution to blind and visually impaired people in third world countries.

  4. Semi-blind Channel Estimator for OFDM-STC

    Institute of Scientific and Technical Information of China (English)

    WU Yun; LUO Han-wen; SONG Wen-tao; HUANG Jian-guo

    2007-01-01

    Channel state information of OFDM-STC system is required for maximum likelihood decoding. A subspace-based semi-blind method was proposed for estimating the channels of OFDM-STC systems. The channels are first estimated blindly up to an ambiguity parameter utilizing the nature structure of STC, irrespective of the underlying signal constellations. Furthermore, a method was proposed to resolve the ambiguity by using a few pilot symbols. The simulation results show the proposed semi-blind estimator can achieve higher spectral efficiency and provide improved estimation performance compared to the non-blind estimator.

  5. Enhanced Chemosensory Detection of Negative Emotions in Congenital Blindness

    Directory of Open Access Journals (Sweden)

    Katrine D. Iversen

    2015-01-01

    Full Text Available It is generally acknowledged that congenitally blind individuals develop superior sensory abilities in order to compensate for their lack of vision. Substantial research has been done on somatosensory and auditory sensory information processing of the blind. However, relatively little information is available about compensatory plasticity in the olfactory domain. Although previous studies indicate that blind individuals have superior olfactory abilities, no studies so far have investigated their sense of smell in relation to social and affective communication. The current study compares congenitally blind and normal sighted individuals in their ability to discriminate and identify emotions from body odours. A group of 14 congenitally blind and 14 age- and sex-matched sighted control subjects participated in the study. We compared participants’ abilities to detect and identify by smelling sweat from donors who had been watching excerpts from emotional movies showing amusement, fear, disgust, or sexual arousal. Our results show that congenitally blind subjects outperformed sighted controls in identifying fear from male donors. In addition, there was a strong tendency that blind individuals were also better in detecting disgust. Our findings reveal that congenitally blind individuals are better at identifying ecologically important emotions and provide new insights into the mechanisms of social and affective communication in blindness.

  6. Fuzzy-based simulation of real color blindness.

    Science.gov (United States)

    Lee, Jinmi; dos Santos, Wellington P

    2010-01-01

    About 8% of men are affected by color blindness. That population is at a disadvantage since they cannot perceive a substantial amount of the visual information. This work presents two computational tools developed to assist color blind people. The first one tests color blindness and assess its severity. The second tool is based on Fuzzy Logic, and implements a method proposed to simulate real red and green color blindness in order to generate synthetic cases of color vision disturbance in a statistically significant amount. Our purpose is to develop correction tools and obtain a deeper understanding of the accessibility problems faced by people with chromatic visual impairment.

  7. IDENTIFYING AUTISM IN CHILDREN WITH BLINDNESS AND VISUAL IMPAIRMENTS

    Directory of Open Access Journals (Sweden)

    Ana VELJANOVSKA

    2000-06-01

    Full Text Available Often in working with children with blindness or visual impairments we are enchanting children with some specific stereotype behaviors, identified as "blindizms”. Parents and professionals noted that many of these behaviors are the same as or similar to those behaviors seen in students with autism. These similarities led professionals to pursue more information about autism and its relationship to blindness. To assist in this process the professionals from Oregon School for the blind developed some guidelines to compare the characteristics observed in children with blindness and autism alone, across four domains: language and communication, relating to people, discrepancies in developmental rates and responses to sensory stimuli.

  8. Ptychographic reconstruction of attosecond pulses

    CERN Document Server

    Lucchini, M; Ludwig, A; Gallmann, L; Keller, U; Feurer, T

    2015-01-01

    We demonstrate a new attosecond pulse reconstruction modality which uses an algorithm that is derived from ptychography. In contrast to other methods, energy and delay sampling are not correlated, and as a result, the number of electron spectra to record is considerably smaller. Together with the robust algorithm, this leads to a more precise and fast convergence of the reconstruction.

  9. Extended object reconstruction in adaptive-optics imaging: the multiresolution approach

    CERN Document Server

    Gallé, Roberto Baena; Gladysz, Szymon

    2012-01-01

    We propose the application of multiresolution transforms, such as wavelets (WT) and curvelets (CT), to the reconstruction of images of extended objects that have been acquired with adaptive optics (AO) systems. Such multichannel approaches normally make use of probabilistic tools in order to distinguish significant structures from noise and reconstruction residuals. Furthermore, we aim to check the historical assumption that image-reconstruction algorithms using static PSFs are not suitable for AO imaging. We convolve an image of Saturn taken with the Hubble Space Telescope (HST) with AO PSFs from the 5-m Hale telescope at the Palomar Observatory and add both shot and readout noise. Subsequently, we apply different approaches to the blurred and noisy data in order to recover the original object. The approaches include multi-frame blind deconvolution (with the algorithm IDAC), myopic deconvolution with regularization (with MISTRAL) and wavelets- or curvelets-based static PSF deconvolution (AWMLE and ACMLE algo...

  10. AN EXPERT APPROACH ON AUTOMATIC SOLID MODEL RECONSTRUCTION FROM 2D PROJECTIONS

    Directory of Open Access Journals (Sweden)

    İsmail ŞAHİN

    2008-02-01

    Full Text Available This paper examines how to automatically reconstruct three dimentions (3D models from their orthographic two and three views and explains a new approach developed for that purpose. The approach is based on the identification of geometric features with the interpretation of 2B views, their volumetric intersections and reconstruction of solid models. A number of rules have been defined for this goal and they implemented on a prototype software with the approach of expert systems. The developed software allows determination of some features efficiently such as slot, holes, blind holes, closed prismatic holes, etc. Another contrubition of this research is to reconstruct solid models from their full section and half section views that is almost noneexistend in the releated literature.

  11. Indoor space 3D visual reconstruction using mobile cart with laser scanner and cameras

    Science.gov (United States)

    Gashongore, Prince Dukundane; Kawasue, Kikuhito; Yoshida, Kumiko; Aoki, Ryota

    2017-02-01

    Indoor space 3D visual reconstruction has many applications and, once done accurately, it enables people to conduct different indoor activities in an efficient manner. For example, an effective and efficient emergency rescue response can be accomplished in a fire disaster situation by using 3D visual information of a destroyed building. Therefore, an accurate Indoor Space 3D visual reconstruction system which can be operated in any given environment without GPS has been developed using a Human-Operated mobile cart equipped with a laser scanner, CCD camera, omnidirectional camera and a computer. By using the system, accurate indoor 3D Visual Data is reconstructed automatically. The obtained 3D data can be used for rescue operations, guiding blind or partially sighted persons and so forth.

  12. Are temperature reconstructions regionally biased?

    CERN Document Server

    Bothe, O

    2012-01-01

    Are temperature reconstructions possibly biased due to regionally differing density of utilized proxy-networks? This question is assessed utilizing a simple process-based forward model of tree growth in the virtual reality of two simulations of the climate of the last millennium with different amplitude of solar forcing variations. The pseudo-tree ring series cluster in high latitudes of the northern hemisphere and east Asia. Only weak biases are found for the full network. However, for a strong solar forcing amplitude the high latitudes indicate a warmer first half of the last millennium while mid-latitudes and Asia were slightly colder than the extratropical hemispheric average. Reconstruction skill is weak or non-existent for two simple reconstruction schemes, and comparison of virtual reality target and reconstructions reveals strong deficiencies. The temporal resolution of the proxies has an influence on the reconstruction task and results are sensitive to the construction of the proxy-network. Existing ...

  13. 20 CFR 416.984 - If you are statutorily blind and still working.

    Science.gov (United States)

    2010-04-01

    ... INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Blindness § 416.984 If you are statutorily blind and still working. There is no requirement that you be unable to work in order... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false If you are statutorily blind and...

  14. Blob-enhanced reconstruction technique

    Science.gov (United States)

    Castrillo, Giusy; Cafiero, Gioacchino; Discetti, Stefano; Astarita, Tommaso

    2016-09-01

    A method to enhance the quality of the tomographic reconstruction and, consequently, the 3D velocity measurement accuracy, is presented. The technique is based on integrating information on the objects to be reconstructed within the algebraic reconstruction process. A first guess intensity distribution is produced with a standard algebraic method, then the distribution is rebuilt as a sum of Gaussian blobs, based on location, intensity and size of agglomerates of light intensity surrounding local maxima. The blobs substitution regularizes the particle shape allowing a reduction of the particles discretization errors and of their elongation in the depth direction. The performances of the blob-enhanced reconstruction technique (BERT) are assessed with a 3D synthetic experiment. The results have been compared with those obtained by applying the standard camera simultaneous multiplicative reconstruction technique (CSMART) to the same volume. Several blob-enhanced reconstruction processes, both substituting the blobs at the end of the CSMART algorithm and during the iterations (i.e. using the blob-enhanced reconstruction as predictor for the following iterations), have been tested. The results confirm the enhancement in the velocity measurements accuracy, demonstrating a reduction of the bias error due to the ghost particles. The improvement is more remarkable at the largest tested seeding densities. Additionally, using the blobs distributions as a predictor enables further improvement of the convergence of the reconstruction algorithm, with the improvement being more considerable when substituting the blobs more than once during the process. The BERT process is also applied to multi resolution (MR) CSMART reconstructions, permitting simultaneously to achieve remarkable improvements in the flow field measurements and to benefit from the reduction in computational time due to the MR approach. Finally, BERT is also tested on experimental data, obtaining an increase of the

  15. Blind foreground subtraction for intensity mapping experiments

    Science.gov (United States)

    Alonso, David; Bull, Philip; Ferreira, Pedro G.; Santos, Mário G.

    2015-02-01

    We make use of a large set of fast simulations of an intensity mapping experiment with characteristics similar to those expected of the Square Kilometre Array in order to study the viability and limits of blind foreground subtraction techniques. In particular, we consider three different approaches: polynomial fitting, principal component analysis (PCA) and independent component analysis (ICA). We review the motivations and algorithms for the three methods, and show that they can all be described, using the same mathematical framework, as different approaches to the blind source separation problem. We study the efficiency of foreground subtraction both in the angular and radial (frequency) directions, as well as the dependence of this efficiency on different instrumental and modelling parameters. For well-behaved foregrounds and instrumental effects, we find that foreground subtraction can be successful to a reasonable level on most scales of interest. We also quantify the effect that the cleaning has on the recovered signal and power spectra. Interestingly, we find that the three methods yield quantitatively similar results, with PCA and ICA being almost equivalent.

  16. An artistic exploration of inattention blindness.

    Science.gov (United States)

    Levy, Ellen K

    2011-01-01

    An experiment about inattention blindness was conducted within the context of an art exhibition as opposed to a laboratory context in order to investigate the potential of art as a vehicle to study attention and its disorders. The project utilized a flash animation, Stealing Attention, that was modeled after the movie by Simons and Chabris (1999) but with significant experimental differences, involving context and staging, the emotional salience of the objects depicted, and the prior art viewing experience of participants. The study involved two components: observing if viewers watching an animation in a gallery could be distracted from noticing the disappearance of stolen museum antiquities (the targets) by the overlaid flashing images of a card game (the distractors) and then observing whether repetition of the depicted targets throughout the gallery installation could facilitate a re-direction of attention that allowed viewers to perceive the targets not initially noted in the animation. My findings were that, after viewing the entire installation and then re-viewing the animation, 64% of the viewers who did not initially remark on the targets in the animation were then able to see them. The discussion elaborates on these findings and then considers ways in which the implications of inattention blindness paradigms might be more fully rendered by uniting insights from the two disciplines of art and neuroscience than by either alone.

  17. IMPLEMENTATION OF COLOR-BLIND AID SYSTEM

    Directory of Open Access Journals (Sweden)

    Ruki Harwahyu

    2013-01-01

    Full Text Available Color-blind is a physical defect causing patient loses the ability to recognize colors either particular or the whole of them. This disability is problematic in daily life, moreover in some specific areas that require carefulness eyesight. We propose a vision aid kit with improved user experience, such as finger pointer and voice command-and-response. Our work proofs the design and implementation of color-blind aid system for embedded and mobile device. This study used Windows Embedded Standard 2009, Windows Phone 7, Speech API library, Open CV library and EmguCV wrapper. The performance of each functionality is evaluated. From various testing that are conducted, the system can best detect color samples with precision level of 90.67% on embedded device implementation and 95.33% on mobile device implementation. The best fingertip detection rate attained is 89.6% with normal lighting condition. The voice command works with detection rate of 75.87%, meanwhile for the synthesized speech response, 88, 33% respondents can understood the words well.

  18. Blind image quality assessment via deep learning.

    Science.gov (United States)

    Hou, Weilong; Gao, Xinbo; Tao, Dacheng; Li, Xuelong

    2015-06-01

    This paper investigates how to blindly evaluate the visual quality of an image by learning rules from linguistic descriptions. Extensive psychological evidence shows that humans prefer to conduct evaluations qualitatively rather than numerically. The qualitative evaluations are then converted into the numerical scores to fairly benchmark objective image quality assessment (IQA) metrics. Recently, lots of learning-based IQA models are proposed by analyzing the mapping from the images to numerical ratings. However, the learnt mapping can hardly be accurate enough because some information has been lost in such an irreversible conversion from the linguistic descriptions to numerical scores. In this paper, we propose a blind IQA model, which learns qualitative evaluations directly and outputs numerical scores for general utilization and fair comparison. Images are represented by natural scene statistics features. A discriminative deep model is trained to classify the features into five grades, corresponding to five explicit mental concepts, i.e., excellent, good, fair, poor, and bad. A newly designed quality pooling is then applied to convert the qualitative labels into scores. The classification framework is not only much more natural than the regression-based models, but also robust to the small sample size problem. Thorough experiments are conducted on popular databases to verify the model's effectiveness, efficiency, and robustness.

  19. Mobility aid for blind figure skaters

    Science.gov (United States)

    Acerbi, A.; Graffigna, J. P.; Polimeni, G.; Fernández, H. H.

    2007-11-01

    This work is developed within the scope of rehabilitation technology to enable blind and visually impaired persons read non-Braille material commonly available in digital form to normal-vision readers. This approach, therefore, tries to broaden the reaching capacity for these persons and, thus, allow for better inclusion in social, work, educative and even leisure activities. Specifically, it is devised for reading any kind of text in digital form --books, files, documents, Internet information and exchanges, etc.-- that can be loaded in a PC to be later read on the devised Braille reading line. It consists of a string-like platform of electrodes that simulate, through tactile electrostimulation, the letter characters displayed in Braille fashion. Finger-tip feeling from these electric discharges is caused by stimulating the skin nerve receptors underneath the tip. These electric discharges produce a similar effect as when reading embossed-type characters of traditional Braille-relief paper material. After design and development, experiences were made with blind persons, with fairly satisfactory results. At present, further work is under way in order to improve the system.

  20. SECURING VIRTUAL IMAGES USING BLIND AUTHENTICATION PROTOCOL

    Directory of Open Access Journals (Sweden)

    RAVIKIRAN PEELUKHANA,

    2011-04-01

    Full Text Available The cloud virtualization technology improves the economy of scale for data centers through server consolidation, application consolidation and resources consolidation. Virtualization allows the provider to move Virtual Images from more congested host to less-congested hosts, as required. Enterprises also get improved server reliability, which in turn increases application performance. Despite these benefits, it includes major security challenges with the portability of Virtual Images between different cloud providers.The security and integrity of Virtual images is the foundation for the overall security of the cloud. Many of the Virtual images are intended to be shared by diverse and unrelated users. Unfortunately, existing approaches to cloud security built by cloud practitioners fall short when dealing with Virtual images. Secure transmission of virtual Images can bepossible by providing authentication using Blind Authentication protocol (BAP. The proposed approach authenticates the allocation of virtual images using Blind authentication protocol. It provides provable protection against replay and client side attacks even if the keys of the user are compromised. The encryption also provides template protection, revocability and alleviates the concerns on privacy in widespread use of biometrics. Carrying out the authentication in the encrypted domain is a secure process, while the encryption key acts as an additional layer of security.

  1. Mobility aid for blind figure skaters

    Energy Technology Data Exchange (ETDEWEB)

    Acerbi, A; Graffigna, J P; Polimeni, G; Fernandez, H H [Gabinete de Tecnologia Medica, Fac. de Ingenieria, Universidad Nac. de San Juan Av Libertador San Martin 1109(O), J5400ARL, San Juan (Argentina)

    2007-11-15

    This work is developed within the scope of rehabilitation technology to enable blind and visually impaired persons read non-Braille material commonly available in digital form to normal-vision readers. This approach, therefore, tries to broaden the reaching capacity for these persons and, thus, allow for better inclusion in social, work, educative and even leisure activities. Specifically, it is devised for reading any kind of text in digital form --books, files, documents, Internet information and exchanges, etc.-- that can be loaded in a PC to be later read on the devised Braille reading line. It consists of a string-like platform of electrodes that simulate, through tactile electrostimulation, the letter characters displayed in Braille fashion. Finger-tip feeling from these electric discharges is caused by stimulating the skin nerve receptors underneath the tip. These electric discharges produce a similar effect as when reading embossed-type characters of traditional Braille-relief paper material. After design and development, experiences were made with blind persons, with fairly satisfactory results. At present, further work is under way in order to improve the system.

  2. Blind RRT: A probabilistically complete distributed RRT

    KAUST Repository

    Rodriguez, Cesar

    2013-11-01

    Rapidly-Exploring Random Trees (RRTs) have been successful at finding feasible solutions for many types of problems. With motion planning becoming more computationally demanding, we turn to parallel motion planning for efficient solutions. Existing work on distributed RRTs has been limited by the overhead that global communication requires. A recent approach, Radial RRT, demonstrated a scalable algorithm that subdivides the space into regions to increase the computation locality. However, if an obstacle completely blocks RRT growth in a region, the planning space is not covered and is thus not probabilistically complete. We present a new algorithm, Blind RRT, which ignores obstacles during initial growth to efficiently explore the entire space. Because obstacles are ignored, free components of the tree become disconnected and fragmented. Blind RRT merges parts of the tree that have become disconnected from the root. We show how this algorithm can be applied to the Radial RRT framework allowing both scalability and effectiveness in motion planning. This method is a probabilistically complete approach to parallel RRTs. We show that our method not only scales but also overcomes the motion planning limitations that Radial RRT has in a series of difficult motion planning tasks. © 2013 IEEE.

  3. Porcelain three-dimensional shape reconstruction and its color reconstruction

    Science.gov (United States)

    Yu, Xiaoyang; Wu, Haibin; Yang, Xue; Yu, Shuang; Wang, Beiyi; Chen, Deyun

    2013-01-01

    In this paper, structured light three-dimensional measurement technology was used to reconstruct the porcelain shape, and further more the porcelain color was reconstructed. So the accurate reconstruction of the shape and color of porcelain was realized. Our shape measurement installation drawing is given. Because the porcelain surface is color complex and highly reflective, the binary Gray code encoding is used to reduce the influence of the porcelain surface. The color camera was employed to obtain the color of the porcelain surface. Then, the comprehensive reconstruction of the shape and color was realized in Java3D runtime environment. In the reconstruction process, the space point by point coloration method is proposed and achieved. Our coloration method ensures the pixel corresponding accuracy in both of shape and color aspects. The porcelain surface shape and color reconstruction experimental results completed by proposed method and our installation, show that: the depth range is 860 ˜ 980mm, the relative error of the shape measurement is less than 0.1%, the reconstructed color of the porcelain surface is real, refined and subtle, and has the same visual effect as the measured surface.

  4. Reporting methods of blinding in randomized trials assessing nonpharmacological treatments.

    Directory of Open Access Journals (Sweden)

    Isabelle Boutron

    2007-02-01

    Full Text Available BACKGROUND: Blinding is a cornerstone of treatment evaluation. Blinding is more difficult to obtain in trials assessing nonpharmacological treatment and frequently relies on "creative" (nonstandard methods. The purpose of this study was to systematically describe the strategies used to obtain blinding in a sample of randomized controlled trials of nonpharmacological treatment. METHODS AND FINDINGS: We systematically searched in Medline and the Cochrane Methodology Register for randomized controlled trials (RCTs assessing nonpharmacological treatment with blinding, published during 2004 in high-impact-factor journals. Data were extracted using a standardized extraction form. We identified 145 articles, with the method of blinding described in 123 of the reports. Methods of blinding of participants and/or health care providers and/or other caregivers concerned mainly use of sham procedures such as simulation of surgical procedures, similar attention-control interventions, or a placebo with a different mode of administration for rehabilitation or psychotherapy. Trials assessing devices reported various placebo interventions such as use of sham prosthesis, identical apparatus (e.g., identical but inactivated machine or use of activated machine with a barrier to block the treatment, or simulation of using a device. Blinding participants to the study hypothesis was also an important method of blinding. The methods reported for blinding outcome assessors relied mainly on centralized assessment of paraclinical examinations, clinical examinations (i.e., use of video, audiotape, photography, or adjudications of clinical events. CONCLUSIONS: This study classifies blinding methods and provides a detailed description of methods that could overcome some barriers of blinding in clinical trials assessing nonpharmacological treatment, and provides information for readers assessing the quality of results of such trials.

  5. A blind robust watermarking scheme with non-cascade iterative encrypted kinoform.

    Science.gov (United States)

    Deng, Ke; Yang, Guanglin; Xie, Haiyan

    2011-05-23

    A blind robust watermarking scheme is proposed. A watermark is firstly transformed into a non-cascade iterative encrypted kinoform with non-cascade phase retrieve algorithm and random fractional Fourier transform (RFrFT). An iterative algorithm and Human Visual System (HVS) are both presented to adaptively embed the kinoform watermark into corresponding 2-level DWT coefficients of the cover image. The kinoform accounts for much less data amount to be embedded than regular computer-generated hologram (CGH). And the kinoform can be extracted with the only right phase key and right fractional order, and reconstructed to represent original watermark without original cover image. The experiments have shown the scheme's high security, good imperceptibility, and robustness to resist attacks such as noise, compression, filtering, cropping.

  6. Evidence-Based ACL Reconstruction

    Directory of Open Access Journals (Sweden)

    E. Carlos RODRIGUEZ-MERCHAN

    2015-01-01

    Full Text Available There is controversy in the literature regarding a number of topics related to anterior cruciate ligament (ACLreconstruction. The purpose of this article is to answer the following questions: 1 Bone patellar tendon bone (BPTB reconstruction or hamstring reconstruction (HR; 2 Double bundle or single bundle; 3 Allograft or authograft; 4 Early or late reconstruction; 5 Rate of return to sports after ACL reconstruction; 6 Rate of osteoarthritis after ACL reconstruction. A Cochrane Library and PubMed (MEDLINE search of systematic reviews and meta-analysis related to ACL reconstruction was performed. The key words were: ACL reconstruction, systematic reviews and meta-analysis. The main criteria for selection were that the articles were systematic reviews and meta-analysesfocused on the aforementioned questions. Sixty-nine articles were found, but only 26 were selected and reviewed because they had a high grade (I-II of evidence. BPTB-R was associated with better postoperative knee stability but with a higher rate of morbidity. However, the results of both procedures in terms of functional outcome in the long-term were similar. The double-bundle ACL reconstruction technique showed better outcomes in rotational laxity, although functional recovery was similar between single-bundle and double-bundle. Autograft yielded better results than allograft. There was no difference between early and delayed reconstruction. 82% of patients were able to return to some kind of sport participation. 28% of patients presented radiological signs of osteoarthritis with a follow-up of minimum 10 years.

  7. AODA Training Experiences of Blindness and Visual Impairment Professionals

    Science.gov (United States)

    Davis, S. J.; Koch, D. Shane; McKee, Marissa F.; Nelipovich, Michael

    2009-01-01

    Co-existing alcohol and other drug abuse (AODA) and blindness or visually impairment may complicate the delivery of rehabilitation services. Professionals working with individuals who are blind or visually impaired need to be aware of unique issues facing those with co-existing disabilities. This study sought to examine the AODA training needs,…

  8. Use of the Cranmer Abacus by Blind Persons.

    Science.gov (United States)

    Nester, Mary Anne

    Described is the use by blind persons of the Cranmer abacus, a computational device adapted from the Japanese abacus. Noted is the lack of carefully controlled research on its use. A comparison of calculation by abacus and by paper and pencil is said to indicate that the use of such mechanical devices does not give the blind competitor an undue…

  9. [Rudolph Tegner: The blind from Marrakech (1949-1950)].

    Science.gov (United States)

    Norn, M; Permin, H

    1999-01-01

    The Danish sculptor and painter Rudolph Tegner (1873-1950) has built his own Museum in Dronningmolle, where his sculptures enrich the unique landscape. His last and incomplete plaster on a simple, raw wooden scaffold sculpture The Blind from Marrakech (Fig. 1) show five persons moan about, carrying a dead body. All persons are missing their arms. Tegner had a number of years earlier been in Marrakech and had watched a funeral procession, where blind beggars had carried a dead old woman raised high above the bearers on a kind of pall. In a small version of the statue cast, later in bronze from 1963, showed 15 bearers, on both sides of the bier (Fig. 2 & 3). Nine and 15 bearers are looking up, two right in front, and the rest are looking down. Totally blind people can not see the light but can see up to the divine Heaven. Some blind have kept the gleam. The confusion with the eye direction shows that they really are blind. However 10 of the 15 blind people had hollow in the eye (excenteratio orbitae) in contrast to the dead woman. The dead woman had been the blinds' mistress. The last work The Blind in Marrakech may also be the despair of the artist.

  10. Recognition of Rapid Speech by Blind and Sighted Older Adults

    Science.gov (United States)

    Gordon-Salant, Sandra; Friedman, Sarah A.

    2011-01-01

    Purpose: To determine whether older blind participants recognize time-compressed speech better than older sighted participants. Method: Three groups of adults with normal hearing participated (n = 10/group): (a) older sighted, (b) older blind, and (c) younger sighted listeners. Low-predictability sentences that were uncompressed (0% time…

  11. Blindness and Consciousness: new lights from the dark

    DEFF Research Database (Denmark)

    Pietrini, Pietro; Ptito, M.; Kupers, R.

    2009-01-01

    who has never had any visual perception form an image of the external world? Do brains from sighted and blind individuals differ and how? In this chapter we discuss recent findings from research in animals as well from functional brain imaging studies in sighted and blind individuals that are shedding...

  12. Blindness as A Challenging Medical and Social Problem in China

    Institute of Scientific and Technical Information of China (English)

    Shixing Hu

    2002-01-01

    China, a country with about one fifth of the world' s population, has been gaining a rapideconomic growth since 1980s. This country has around 5 million blind people, accountingfor 18% of the blind in the world. The major causes of blindness include cataract,corneal diseases, trachoma, glaucoma, vitreoretinopathy and a number of factorscontributing to blindness in children. The principal cause of blindness in China was nolonger trachoma but cataracts. Vitamin A deficiency remains a public health problem inthe under-developed areas.Age-related conditions in China, such as vision loss due tocataract and retinal disorders, will increase accordingly if no preventive meaunes aretaken. Glaucoma and diabetic retinopathy appear to be predominant induction of thedevastating blind. In this fast developing country blindness is not only a medical orhealth, but also a social problem. Developed strategies have been adopted simultaneouslyby national efforts under the leadership of the government, international agencies,nongovernmental organizations, as well as private sectors in their every-day work toprevent and treat blindness.

  13. 77 FR 64217 - Blind Americans Equality Day, 2012

    Science.gov (United States)

    2012-10-18

    ... several who are blind, as Champions of Change for their work to expand educational and employment... October 18, 2012 Part III The President Proclamation 8889--Blind Americans Equality Day, 2012 #0; #0; #0... / Presidential Documents#0;#0; #0; #0;Title 3-- #0;The President ] Proclamation 8889 of October 15, 2012...

  14. Differences in Soccer Kick Kinematics between Blind Players and Controls

    Science.gov (United States)

    Giagazoglou, Paraskevi; Katis, Athanasios; Kellis, Eleftherios; Natsikas, Christos

    2011-01-01

    The purpose of the current study was to examine the kinematic differences during instep soccer kicks between players who were blind and sighted controls. Eleven male soccer players who were blind and nine male sighted performed instep kicks under static and dynamic conditions. The results indicated significantly higher (p less than 0.05) ball…

  15. 76 FR 58412 - Relay Services for Deaf-Blind Individuals

    Science.gov (United States)

    2011-09-21

    ... COMMISSION 47 CFR Part 64 Relay Services for Deaf-Blind Individuals AGENCY: Federal Communications Commission... Communications and Video Accessibility Act of 2010, Section 105, Relay Services for Deaf-Blind Individuals...-First Century Communications and Video Accessibility Act of 2010, Section 105, Relay Services for...

  16. 76 FR 26641 - Relay Services for Deaf-Blind Individuals

    Science.gov (United States)

    2011-05-09

    ... COMMISSION 47 CFR Part 64 Relay Services for Deaf-Blind Individuals AGENCY: Federal Communications Commission. ACTION: Final rule. SUMMARY: In this document, the Commission adopts rules to establish the National Deaf... specialized customer premises equipment (CPE) to low- income individuals who are deaf-blind. For...

  17. 77 FR 20553 - Relay Services for Deaf-Blind Individuals

    Science.gov (United States)

    2012-04-05

    ... COMMISSION 47 CFR Part 64 Relay Services for Deaf-Blind Individuals AGENCY: Federal Communications Commission... the requirement for National Deaf Blind Equipment Distribution Program (NDBEDP) certified programs to... to better enable selected participants to fully meet the needs of eligible low- income,...

  18. Validity of False Belief Tasks in Blind Children

    Science.gov (United States)

    Brambring, Michael; Asbrock, Doreen

    2010-01-01

    Previous studies have reported that congenitally blind children without any additional impairment reveal a developmental delay of at least 4 years in perspective taking based on testing first-order false-belief tasks. These authors interpret this delay as a sign of autism-like behavior. However, the delay may be caused by testing blind children…

  19. Understanding and Creating Accessible Touch Screen Interactions for Blind People

    Science.gov (United States)

    Kane, Shaun K.

    2011-01-01

    Using touch screens presents a number of usability and accessibility challenges for blind people. Most touch screen-based user interfaces are optimized for visual interaction, and are therefore difficult or impossible to use without vision. This dissertation presents an approach to redesigning gesture-based user interfaces to enable blind people…

  20. Alterations in right posterior hippocampus in early blind individuals

    DEFF Research Database (Denmark)

    Chebat, Daniel-Robert; Chen, Jan-Kai; Schneider, Fabien

    2007-01-01

    This study compares hippocampal volumes of early blind and sex/age-matched sighted controls through volumetric and localization analyses. Early blind individuals showed a significantly smaller right posterior hippocampus compared with controls. No differences in total hippocampal volumes were fou...

  1. Affective Reactions in Some Parents of Deaf-Blind Children.

    Science.gov (United States)

    Torrie, Carolyn

    Emotional problems and behavioral patterns of parents who have deaf blind children are described clinically and in short case studies. Deaf blind young children are said to be isolated from their families due to lack of sensory cues; to display behaviors such as back arching and fear of walking; and to experience frequent health crises such as…

  2. Encoding audio motion: spatial impairment in early blind individuals

    Directory of Open Access Journals (Sweden)

    Sara eFinocchietti

    2015-09-01

    Full Text Available The consequence of blindness on auditory spatial localization has been an interesting issue of research in the last decade providing mixed results. Enhanced auditory spatial skills in individuals with visual impairment have been reported by multiple studies, while some aspects of spatial hearing seem to be impaired in the absence of vision. In this study, the ability to encode the trajectory of a 2 dimensional sound motion, reproducing the complete movement, and reaching the correct end-point sound position, is evaluated in 12 early blind individuals, 8 late blind individuals, and 20 age-matched sighted blindfolded controls. Early blind individuals correctly determine the direction of the sound motion on the horizontal axis, but show a clear deficit in encoding the sound motion in the lower side of the plane. On the contrary, late blind individuals and blindfolded controls perform much better with no deficit in the lower side of the plane. In fact the mean localization error resulted 271 ± 10 mm for early blind individuals, 65 ± 4 mm for late blind individuals, and 68 ± 2 mm for sighted blindfolded controls.These results support the hypothesis that i it exists a trade-off between the development of enhanced perceptual abilities and role of vision in the sound localization abilities of early blind individuals, and ii the visual information is fundamental in calibrating some aspects of the representation of auditory space in the brain.

  3. Cortical blindness in a child with acute glomerulonephritis.

    Science.gov (United States)

    Kaarthigeyan, K; Vijayalakshmi, A M

    2012-01-01

    The association between hypertensive encephalopathy and cortical blindness in children with acute glomerulonephritis is extremely rare. We report the case of a 9-year old girl who presented with headache, seizures, altered sensorium, hematuria, and transient cortical blindness as a complication of hypertensive encephalopathy which showed complete reversal following normalization of blood pressure and an underlying post-infectious acute glomerulonephritis was revealed.

  4. The Cortically Blind Infant: Educational Guidelines and Suggestions.

    Science.gov (United States)

    Silverrain, Ann

    Cortical blindness is defined and its diagnosis is explained. Guidelines and sample activities are presented for use in a cognitive/visual/multi-sensory stimulation program to produce progress in cortically blind infants. The importance of using the eyes from birth through early development in order to form the nerve pathways responsible for…

  5. Reconstruction of B mesons

    Science.gov (United States)

    Albrecht, H.; Binder, U.; Böckmann, P.; Gläser, R.; Harder, G.; Lembke-Koppitz, I.; Schmidt-Parzefall, W.; Schröder, H.; Schulz, H. D.; Wurth, R.; Yagil, A.; Donker, J. P.; Drescher, A.; Kamp, D.; Matthiesen, U.; Scheck, H.; Spaan, B.; Spengler, J.; Wegener, D.; Gabriel, J. C.; Schubert, K. R.; Stiewe, J.; Strahl, K.; Waldi, R.; Weseler, S.; Edwards, K. W.; Frisken, W. R.; Gilkinson, D. J.; Gingrich, D. M.; Kapitza, H.; Kim, P. C. H.; Kutschke, R.; Macfarlane, D. B.; McKenna, J. A.; McLean, K. W.; Nilsson, A. W.; Orr, R. S.; Padley, P.; Parsons, J. A.; Patel, P. M.; Prentice, J. D.; Seywerd, H. C. J.; Swain, J. D.; Tsipolitis, G.; Yoon, T.-S.; Yun, J. C.; Ammar, R.; Coppage, D.; Davis, R.; Kanekal, S.; Kwak, N.; Boštjančič, B.; Kernel, G.; Pleško, M.; Jönsson, L.; Babaev, A.; Danilov, M.; Golutvin, A.; Gorelov, I.; Lubimov, V.; Matveev, V.; Nagovitsin, V.; Ryltsov, V.; Semenov, A.; Shevchenko, V.; Soloshenko, V.; Tchistilin, V.; Tichomirov, I.; Zaitzev, Yu.; Childers, R.; Darden, C. W.; Oku, Y.; Gennow, H.; Argus Collaboration

    1987-02-01

    B mesons have been reconstructed in five decay channels of the type B→D ∗±nπ(n=1,2,3) using data accumulated by the ARGUS experiment at the e +e - storage ring DORIS II at DESY. In total, we find 40 neutral B mesons above a background of 15±6 events with a mass of (5278.2±1.0±3.0) MeV/ c2 and 32 charged B mesons above a background of 17±6 events with a mass of (5275.8±1.3±3.0) MeV/ c2. The decays overlineB0D∗+π -π 0, overlineB0D∗+π -π -π +, and B-→ D∗+π -π -π 0 have been observed for the first time. We find substantially smaller branching ratios for the decay modes overlineB0→ D∗+π - and B-→ D∗+π -π - than previously published by the CLEO collaboration.

  6. Reconstructing human evolution

    CERN Document Server

    Cavalli-Sforza, M

    1999-01-01

    One can reconstruct human evolution using modern genetic data and models based on the mathematical theory of evolution and its four major factors : mutation, natural selection, statistical fluctuations in finite populations (random genetic drift), and migration. Archaeology gives some help on the major dates and events of the process. Chances of studying ancient DNA are very limited but there have been a few successful results. Studying DNA instead of proteins, as was done until a few years ago, and in particular the DNA of mitochondria and of the Y chromosome which are transmitted, respectively, by the maternal line and the paternal line, has greatly simplified the analysis. It is now possible to carry the analysis on individuals, while earlier studies were of necessity based on populations. Also the evolution of ÒcultureÓ (i.e. what we learn from others), in particular that of languages, gives some help and can be greatly enlightened by genetic studies. Even though it is largely based on mechanisms of mut...

  7. Facial Reconstruction and Rehabilitation.

    Science.gov (United States)

    Guntinas-Lichius, Orlando; Genther, Dane J; Byrne, Patrick J

    2016-01-01

    Extracranial infiltration of the facial nerve by salivary gland tumors is the most frequent cause of facial palsy secondary to malignancy. Nevertheless, facial palsy related to salivary gland cancer is uncommon. Therefore, reconstructive facial reanimation surgery is not a routine undertaking for most head and neck surgeons. The primary aims of facial reanimation are to restore tone, symmetry, and movement to the paralyzed face. Such restoration should improve the patient's objective motor function and subjective quality of life. The surgical procedures for facial reanimation rely heavily on long-established techniques, but many advances and improvements have been made in recent years. In the past, published experiences on strategies for optimizing functional outcomes in facial paralysis patients were primarily based on small case series and described a wide variety of surgical techniques. However, in the recent years, larger series have been published from high-volume centers with significant and specialized experience in surgical and nonsurgical reanimation of the paralyzed face that have informed modern treatment. This chapter reviews the most important diagnostic methods used for the evaluation of facial paralysis to optimize the planning of each individual's treatment and discusses surgical and nonsurgical techniques for facial rehabilitation based on the contemporary literature.

  8. Non-parametric PSF estimation from celestial transit solar images using blind deconvolution

    Science.gov (United States)

    González, Adriana; Delouille, Véronique; Jacques, Laurent

    2016-01-01

    Context: Characterization of instrumental effects in astronomical imaging is important in order to extract accurate physical information from the observations. The measured image in a real optical instrument is usually represented by the convolution of an ideal image with a Point Spread Function (PSF). Additionally, the image acquisition process is also contaminated by other sources of noise (read-out, photon-counting). The problem of estimating both the PSF and a denoised image is called blind deconvolution and is ill-posed. Aims: We propose a blind deconvolution scheme that relies on image regularization. Contrarily to most methods presented in the literature, our method does not assume a parametric model of the PSF and can thus be applied to any telescope. Methods: Our scheme uses a wavelet analysis prior model on the image and weak assumptions on the PSF. We use observations from a celestial transit, where the occulting body can be assumed to be a black disk. These constraints allow us to retain meaningful solutions for the filter and the image, eliminating trivial, translated, and interchanged solutions. Under an additive Gaussian noise assumption, they also enforce noise canceling and avoid reconstruction artifacts by promoting the whiteness of the residual between the blurred observations and the cleaned data. Results: Our method is applied to synthetic and experimental data. The PSF is estimated for the SECCHI/EUVI instrument using the 2007 Lunar transit, and for SDO/AIA using the 2012 Venus transit. Results show that the proposed non-parametric blind deconvolution method is able to estimate the core of the PSF with a similar quality to parametric methods proposed in the literature. We also show that, if these parametric estimations are incorporated in the acquisition model, the resulting PSF outperforms both the parametric and non-parametric methods.

  9. Modeling and Reconstruction of Mixed Functional and Molecular Patterns

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available Functional medical imaging promises powerful tools for the visualization and elucidation of important disease-causing biological processes in living tissue. Recent research aims to dissect the distribution or expression of multiple biomarkers associated with disease progression or response, where the signals often represent a composite of more than one distinct source independent of spatial resolution. Formulating the task as a blind source separation or composite signal factorization problem, we report here a statistically principled method for modeling and reconstruction of mixed functional or molecular patterns. The computational algorithm is based on a latent variable model whose parameters are estimated using clustered component analysis. We demonstrate the principle and performance of the approaches on the breast cancer data sets acquired by dynamic contrast-enhanced magnetic resonance imaging.

  10. Image Interpolation Through Surface Reconstruction

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ling; LI Xue-mei

    2013-01-01

    Reconstructing an HR (high-resolution) image which preserves the image intrinsic structures from its LR ( low-resolution) counterpart is highly challenging. This paper proposes a new surface reconstruction algorithm applied to image interpolation. The interpolation surface for the whole image is generated by putting all the quadratic polynomial patches together. In order to eliminate the jaggies of the edge, a new weight function containing edge information is incorporated into the patch reconstruction procedure as a constraint. Extensive experimental results demonstrate that our method produces better results across a wide range of scenes in terms of both quantitative evaluation and subjective visual quality.

  11. A new wavelet-based reconstruction algorithm for twin image removal in digital in-line holography

    Science.gov (United States)

    Hattay, Jamel; Belaid, Samir; Aguili, Taoufik; Lebrun, Denis

    2016-07-01

    Two original methods are proposed here for digital in-line hologram processing. Firstly, we propose an entropy-based method to retrieve the focus plane which is very useful for digital hologram reconstruction. Secondly, we introduce a new approach to remove the so-called twin images reconstructed by holograms. This is achieved owing to the Blind Source Separation (BSS) technique. The proposed method is made up of two steps: an Adaptive Quincunx Lifting Scheme (AQLS) and a statistical unmixing algorithm. The AQLS tool is based on wavelet packet transform, whose role is to maximize the sparseness of the input holograms. The unmixing algorithm uses the Independent Component Analysis (ICA) tool. Experimental results confirm the ability of convolutive blind source separation to discard the unwanted twin image from in-line digital holograms.

  12. Multi-proxy Strong Blind Quantum Signature Scheme

    Science.gov (United States)

    Guo, Wei; Zhang, Jian-Zhong; Li, Yan-Ping; An, Wan

    2016-08-01

    A multi-proxy strong blind quantum signature scheme is proposed in this paper. An original signatory Alice delegates her signing authority to a group of proxy signatories by using a classical warrant. A blind factor is introduced by a sender U to blind a message, and the proxy signatories sign the message blindly via applying appropriate unitary operators. A receiver Bob verifies the generated signature with the help of an arbitrator Trent. The security of this scheme is based on a quantum key distribution protocol, a quantum one-time pad and other quantum properties. It is proved that our scheme has the properties of non-disavowal, non-counterfeit, multi-proxy, blindness, untraceability and can resist some common attacks.

  13. Superior Orthonasal but Not Retronasal Olfactory Skills in Congenital Blindness

    DEFF Research Database (Denmark)

    Gagnon, Lea; Ismaili, Abd Rahman Alaoui; Ptito, Maurice

    2015-01-01

    Sight is undoubtedly important for finding and appreciating food, and cooking. Blind individuals are strongly impaired in finding food, limiting the variety of flavours they are exposed to. We have shown before that compared to sighted controls, congenitally blind individuals have enhanced...... olfactory but reduced taste perception. In this study we tested the hypothesis that congenitally blind subjects have enhanced orthonasal but not retronasal olfactory skills. Twelve congenitally blind and 14 sighted control subjects, matched in age, gender and body mass index, were asked to identify odours...... using grocery-available food powders. Results showed that blind subjects were significantly faster and tended to be better at identifying odours presented orthonasally. This was not the case when odorants were presented retronasally. We also found a significant group x route interaction, showing...

  14. Blind trust in unblinded observation in Ecology, Evolution and Behavior

    Directory of Open Access Journals (Sweden)

    Melissa R Kardish

    2015-05-01

    Full Text Available We survey 492 recent studies in the fields of ecology, evolution and behavior (EEB to evaluate potential for observer bias and the need for blind experimentation in each study. While 248 articles included experiments that could have been influenced by observer bias, only 13.3% of these articles indicated that experiments were blinded. The use of blind observation therefore was either grossly underreported in the surveyed articles, or many EEB studies were not blinded. We hope that a concerted effort of the field of EEB – including researchers, peer-reviewers, and journal editors – will help promote and institute routine, blind observation as an essential standard that should be practiced by all sciences.

  15. Designing for an inclusive school of informatics for blind students

    DEFF Research Database (Denmark)

    Vargas Brenes, Ronald

    Today it is not uncommon to see disabled people attend universities. These include in particular mobility impaired people and blind people, but they are not the only ones, as other impairments can for example be hidden under the ‘normality’ of other students, teachers and administrative staff...... at universities. As a university teacher it became obvious to me that there were no blind students at the School of Informatics at Universidad Nacional UNA in Costa Rica. This is surprising as this school has some of the university’s most attractive programmes. I learned that most of the blind people who were...... initiative to do so. It was at that moment that I shifted my focus from trying to understand why blind students were not interested in informatics and started to question whether the School of Informatics was prepared to receive blind students. As I was a teacher in this school I could start by asking myself...

  16. Hypnotic color blindness and performance on the Stroop test.

    Science.gov (United States)

    Mallard, D; Bryant, R A

    2001-10-01

    A suggestion for hypnotic color blindness was investigated by administering a reverse Stroop color-naming task. Prior to the suggestion for color blindness, participants learned associations between color names and shapes. Following the color blindness suggestion, participants were required to name the shapes when they appeared in colors that were either congruent or incongruent with the learned associations. The 18 high hypnotizable participants who passed the suggestion were slower to name (a) shapes in which the color name was incongruent with the color in which it was printed, (b) "unseen" rather than "seen" shapes, and (c) color-incongruent shapes that were printed in the color in which they were "color-blind." These patterns are discussed in terms of potential cognitive and social mechanisms that may mediate responses to hypnotic color blindness.

  17. Cataract related blindness in India & its social implications.

    Science.gov (United States)

    Angra, S K; Murthy, G V; Gupta, S K; Angra, V

    1997-10-01

    The prevalence of blindness in India is 14.9 per 1000. Eighty per cent of this blindness is due to cataract alone. Most of the cataract blinds in the country are in the rural areas while the surgical service delivery network is concentrated in the urban areas. Thus a large proportion of patients in the rural areas continue to remain blind. This situation has many social implications. There is loss of productivity, breakdown of interpersonal relationships, depressive manifestations, loss of self esteem and most patients lead an isolated humiliating life. Patients lack information on the available services and continue to remain blind for years even after being diagnosed as operable. This is unfortunate because cataract surgery is one of the most cost effective health interventions known and most operated patients, irrespective of the surgical technique, are immensely satisfied with the level of visual rehabilitation after surgery.

  18. A Weak Quantum Blind Signature with Entanglement Permutation

    Science.gov (United States)

    Lou, Xiaoping; Chen, Zhigang; Guo, Ying

    2015-09-01

    Motivated by the permutation encryption algorithm, a weak quantum blind signature (QBS) scheme is proposed. It involves three participants, including the sender Alice, the signatory Bob and the trusted entity Charlie, in four phases, i.e., initializing phase, blinding phase, signing phase and verifying phase. In a small-scale quantum computation network, Alice blinds the message based on a quantum entanglement permutation encryption algorithm that embraces the chaotic position string. Bob signs the blinded message with private parameters shared beforehand while Charlie verifies the signature's validity and recovers the original message. Analysis shows that the proposed scheme achieves the secure blindness for the signer and traceability for the message owner with the aid of the authentic arbitrator who plays a crucial role when a dispute arises. In addition, the signature can neither be forged nor disavowed by the malicious attackers. It has a wide application to E-voting and E-payment system, etc.

  19. A THRESHOLD BLIND SIGNATURE FROM WEIL PAIRING ON ELLIPTIC CURVES

    Institute of Scientific and Technical Information of China (English)

    Cheng Xiangguo; Xu Weidong; Wang Xinmei

    2006-01-01

    The idea behind a (t, n) threshold blind signature is that a user can ask at least t out ofn players of a group to cooperate to generate a signature for a message without revealing its content. This paper first presents a new blind signature scheme from Weil pairing on elliptic curves. Based on this scheme, a threshold blind signature scheme is proposed. It is efficient and has the security properties of robustness and unforgeability. In the proposed scheme, the group manger is introduced to take the role of distributing the group secret key to each player. However, he cannot forge the players to generate partial blind signatures (Each partial blind signature depends on not only the secret key of the player, but also a random number the player picks). Compared with a threshold signature with a trusted third party, its advantage is obvious; Compared with a threshold signature without a trusted third party, it is more simple and efficient.

  20. Blind analysis results of the TWIST experiment

    CERN Document Server

    Hillairet, A; Bueno, J F; Davydov, Y I; Depommier, P; Faszer, W; Fujiwara, M C; Gagliardi, C A; Gaponenko, A; Grossheim, A; Gill, D R; Gumplinger, P; Hasinoff, M D; Henderson, R S; Hu, J; Koetke, D D; MacDonald, R P; Marshall, G M; Mathie, E W; Mischke, R E; Olchanski, K; Olin, A; Openshaw, R; Poutissou, J -M; Poutissou, R; Selivanov, V; Sheffer, G; Shin, B; Stanislaus, T D S; Tacik, R; Tribble, R E

    2010-01-01

    The TRIUMF Weak Interaction Symmetry Test (TWIST) experiment was designed to test the standard model at high precision in the purely leptonic decay of polarized muons. A general four-fermion interaction model is used to describe the muon decay. TWIST measures three of the four muon decay parameters of this model, $\\rho$, $\\delta$ and $P_{\\mu}^{\\pi} \\xi$, from the shape of the momentum-angle spectrum. The results of this model independent approach are compared to the standard model predictions and used to constrain new physics. Our collaboration has finalized the blind analysis of the final experimental data taken in 2006 and 2007. This analysis mostly reached our goal of a precision of an order of magnitude improvement over the pre-TWIST measurements.

  1. Double blind placebo controlled exposure to molds

    DEFF Research Database (Denmark)

    Meyer, H W; Jensen, K A; Nielsen, K F

    2005-01-01

    non-significant, and at the same level as after placebo exposure. The developed exposure system based on the Particle-Field and Laboratory Emission Cell (P-FLEC) makes it possible to deliver a precise and highly controlled dose of mold spores from water-damaged building materials, imitating realistic....... In conclusion this is, to our knowledge, the first study to successfully conduct a human exposure to a highly controlled dose of fungal material aerosolized directly from wet building materials. This short-term exposure to high concentrations of two different molds induced no more reactions than exposure...... to placebo in eight sensitive school employees. However, a statistical type II error cannot be excluded because of the small sample size. PRACTICAL IMPLICATIONS: In this double blind, placebo controlled study of mold exposure changes in symptoms, objective measurements and blood samples were small and mostly...

  2. Blind Signatures in Electronic Voting Systems

    Science.gov (United States)

    Kucharczyk, Marcin

    Electronic voting systems are created to facilitate the election, accelerate voting and counting votes and increase turnout for the election. The main problems of the electronic systems are related with the assurance of system security (cryptographic security and protection against frauds) and a guarantee that the voters are anonymous. The authorization of voters and the anonymity of them seem to be contradictory, but it is possible to create such a system where the both requirements are met. Some solutions, the most common e-voting systems, are presented in the paper. These models are adjusted to the demands and implemented in the polls system for quality of teaching evaluation where anonymity is very important. The blind signature protocol, model directed to user's anonymity, is a very good solution of the authorization and anonymity problem in the polls system with remote access only, as it was described in the paper.

  3. GA based robust blind digital watermarking

    CERN Document Server

    Álvarez, Víctor; Frau, María-Dolores; Gudiel, Félix; Güemes, María-Belén; Martín, Elena; Osuna, Amparo

    2012-01-01

    A genetic algorithm based robust blind digital watermarking scheme is presented. Starting from a binary image (the original watermark), a genetic algorithm is performed searching for a permutation of this image which is as uncorrelated as possible to the original watermark. The output of the GA is used as our final watermark, so that both security and robustness in the watermarking process is improved. Now, the original cover image is partitioned into non-overlapped square blocks (depending on the size of the watermark image). Then a (possibly extended) Hadamard transform is applied to these blocks, so that one bit information from the watermark image is embedded in each block by modifying the relationship of two coefficients in the transformed matrices. The watermarked image is finally obtained by simply performing the inverse (extended) Hadamard transform on the modified matrices. The experimental results show that our scheme keeps invisibility, security and robustness more likely than other proposals in th...

  4. Iterative surface construction for blind deflectometry

    Science.gov (United States)

    Zhao, Wenchuan; Graves, Logan R.; Huang, Run; Song, Weihong; Kim, DaeWook

    2016-09-01

    Freeform optics provide excellent performance for a wide variety of applications. However, obtaining an accurate freeform surface measurement is highly challenging due to its large aspheric/freeform departure. It has been proven that SCOTS (Software Configurable Optical Test System), an advanced deflectometry system developed at the University of Arizona, can measure the departure of a freeform surface from the desired shape with nanometer accuracy. Here, a new data processing technique was used to measure a freeform surface without any prior knowledge of the shape of the surface. Knowing only the geometry of one point on the test surface, this method can take a blind measurement of a freeform surface and arrive at the true surface through iterative construction.

  5. Attending to music decreases inattentional blindness.

    Science.gov (United States)

    Beanland, Vanessa; Allen, Rosemary A; Pammer, Kristen

    2011-12-01

    This article investigates how auditory attention affects inattentional blindness (IB), a failure of conscious awareness in which an observer does not notice an unexpected event because their attention is engaged elsewhere. Previous research using the attentional blink paradigm has indicated that listening to music can reduce failures of conscious awareness. It was proposed that listening to music would decrease IB by reducing observers' frequency of task-unrelated thoughts (TUTs). Observers completed an IB task that varied both visual and auditory demands. Listening to music was associated with significantly lower IB, but only when observers actively attended to the music. Follow-up experiments suggest this was due to the distracting qualities of the audio task. The results also suggest a complex relationship between IB and TUTs: during demanding tasks, as predicted, noticers of the unexpected stimulus reported fewer TUTs than non-noticers. During less demanding tasks, however, noticers reported more TUTs than non-noticers.

  6. Hologram-reconstruction signal enhancement

    Science.gov (United States)

    Mezrich, R. S.

    1977-01-01

    Principle of heterodyne detection is used to combine object beam and reconstructed virtual image beam. All light valves in page composer are opened, and virtual-image beam is allowed to interfere with light from valves.

  7. Arapahoe NWR diversion reconstruction : Preliminary

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a preliminary plan for a diversion reconstruction for Hubbard #2. Oklahoma #1, Dryer, Hill and Crowder sites on the Arapahoe National Wildlife Refuge.

  8. Rational reconstructions of modern physics

    CERN Document Server

    Mittelstaedt, Peter

    2013-01-01

    Newton’s classical physics and its underlying ontology are loaded with several metaphysical hypotheses that cannot be justified by rational reasoning nor by experimental evidence. Furthermore, it is well known that some of these hypotheses are not contained in the great theories of Modern Physics, such as the theory of Special Relativity and Quantum Mechanics. This book shows that, on the basis of Newton’s classical physics and by rational reconstruction, the theory of Special Relativity as well as Quantum Mechanics can be obtained by partly eliminating or attenuating the metaphysical hypotheses. Moreover, it is shown that these reconstructions do not require additional hypotheses or new experimental results. In the second edition the rational reconstructions are completed with respect to General Relativity and Cosmology. In addition, the statistics of quantum objects is elaborated in more detail with respect to the rational reconstruction of quantum mechanics. The new material completes the approach of t...

  9. Prevalence and causes of low vision and blindness in the blind population supported by the Yazd Welfare Organization

    Directory of Open Access Journals (Sweden)

    F Ezoddini - Ardakani

    2006-01-01

    Full Text Available Introduction: In 1995, the World Health Organization (WHO estimated that there were 37.1 million blind people worldwide. It has subsequently been reported that 110 million people have severely impaired vision, hence are at great risk of becoming blind. Watkins predicted an annual increase of about two million blind worldwide. This study was designed to investigate the causes of blindness and low vision in the blind population supported by the welfare organization of Yazd, Iran. Methods: This clinical descriptive cross-sectional study was done from January to September, 2003. In total, 109 blind patients supported by the welfare organization were included in this study. All data was collected by standard methods using questionnaire, interview and specific examination. The data included; demographic characteristics, clinical states, ophthalmic examination, family history and the available prenatal information. The data were analyzed by SPSS software and chi square test. Results: Of total patients, 73 cases were male (67% and 36 were female (33%. The median age was 24.6 years (range one month to 60 years. More than half of the cases (53.2% could be diagnosed in children less than one year of age. In total, 79 patients (88.1% were legally blind of which 23 cases (29.1% had no light perception (NLP. The most common causes of blindness were retinitis pigmentosa (32.1% followed by ocular dysgenesis (16.5%. Conclusion: Our data showed that more than half of the blindness cases occur during the first year of life. The most common cause of blindness was retinitis pigmentosa followed by ocular dysgenesis, cataract and glaucoma, respectively.

  10. When inclusion was not an issue: the life story of the first blind lawyer trained in Brazil

    Directory of Open Access Journals (Sweden)

    Bento Selau

    2014-06-01

    Full Text Available This work aims to present the findings of an investigation that sought to reconstruct the life story of Walkírio Ughini Bertoldo, considered to be the first blind lawyer to graduate, in Brazil, in 1957. The narrative focuses on the obstacles he faced along the trajectory through this stage of his schooling process, and analyzes the strategies he used to overcome them. The investigative process, which produced Bertoldo´s life story, was guided by the biographical method. Data were collected through interviews with three informants: two college classmates, who later also became his coworkers, and his sister. The research corpus was supplemented by documentary sources related to the subject’s life. The findings showed that the trajectory of Bertoldo through higher education was marked by his great dedication and commitment; showed the resistance of the higher education institution to accept blind undergraduates and strategies he used attend the course, in spite of the lack of adapted resources; his intense professional activity, as well as his outstanding contribution to social development and inclusion of the blind in professional and academic life.

  11. Improving outcomes in aesthetic facial reconstruction.

    Science.gov (United States)

    Hofer, Stefan O P; Mureau, Marc A M

    2009-07-01

    Aesthetic facial reconstruction is a challenging art. Improving outcomes in aesthetic facial reconstruction requires a thorough understanding of the basic principles of the functional and aesthetic requirements for facial reconstruction. From there, further refinement and attention to detail can be provided. This paper discusses basic principles of aesthetic facial reconstruction.

  12. On $\\mathfrak{I}$-reconstruction Property

    OpenAIRE

    L. K. Vashisht; Khattar, Geetika

    2013-01-01

    Reconstruction property in Banach spaces introduced and studied by Casazza and Christensen in [1]. In this paper we introduce reconstruction property in Banach spaces which satisfy $\\mathfrak{I}$-property. A characterization of reconstruction property in Banach spaces which satisfy $\\mathfrak{I}$-property in terms of frames in Banach spaces is obtained. Banach frames associated with reconstruction property are discussed.

  13. Learning strategies used by blind students and psychics

    Directory of Open Access Journals (Sweden)

    Manuela Ramos Caldas Lins

    2016-10-01

    Full Text Available This study aimed to analyze the learning strategies most often used by blind students (study 1 and compare the learning strategies used by blind and sighted students (study 2. The first study involved the participation of 25 blind students, of both sexes, aged between 9 and 16 years, enrolled from 3rd to 9th grade of elementary school. The instruments used were a sociodemographic questionnaire and a semi-structured interview. The data indicated that blind students use both cognitive and metacognitive strategies, but the repertoire variety is little. In study 2, 25 blind and 25 sighted students, of both sexes, aged between 9 and 16 years, enrolled from 3rd to 8th grade of elementary school, completed a sociodemographic questionnaire and a measure of learning strategies. The results showed homogeneity in the responses, indicating that both the blind and the sighted students reported using the same type of learning strategies. We conclude that blind and sighted students use cognitive and metacognitive strategies to study, but this repertoire is rather complex, indicating that they use the same strategies regardless of the content studied or the task to be performed.

  14. Study oOf Important Psychosocial Factors in Institutionalized Blinds

    Directory of Open Access Journals (Sweden)

    Uddhav T Kumbhar, Armaity Dehmubed

    2011-01-01

    Full Text Available Background: Blindness probably is the most feared infirmity of mankind. The blind individuals were considered useless for the centuries till recent development in culture and civilization. Present study was conducted with the aim to study important psychosocial aspects of blinds undergoing formal vocational training in institutes. Objective: to identify candidates’ psychosocial profile using Self Reporting Questionnaire (S.R.Q.. Materials and Methods: it was a cross sectional study conducted in two vocational training institutes for blinds (one for males and other for females in Mumbai. The individuals were subjected to pre tested S.R.Q. and the individuals found positive with this tool and double the number of matched S.R.Q. negative controls from the institute were subjected to psychiatric examination done by qualified psychiatrist. Analysis: analysis was done using fisher’s exact test and chi square test results: 15 (7.18% blinds were found S.R.Q. positive indicating they either have or prone to have psychiatric morbidity. Conclusion: Psychological rehabilitation of the blinds should be considered before planning the vocational training of blinds.

  15. The first rapid assessment of avoidable blindness (RAAB in Thailand.

    Directory of Open Access Journals (Sweden)

    Saichin Isipradit

    Full Text Available BACKGROUND: The majority of vision loss is preventable or treatable. Population surveys are crucial for planning, implementation, and monitoring policies and interventions to eliminate avoidable blindness and visual impairments. This is the first rapid assessment of avoidable blindness (RAAB study in Thailand. METHODS: A cross-sectional study of a population in Thailand age 50 years old or over aimed to assess the prevalence and causes of blindness and visual impairments. Using the Thailand National Census 2010 as the sampling frame, a stratified four-stage cluster sampling based on a probability proportional to size was conducted in 176 enumeration areas from 11 provinces. Participants received comprehensive eye examination by ophthalmologists. RESULTS: The age and sex adjusted prevalence of blindness (presenting visual acuity (VA <20/400, severe visual impairment (VA <20/200 but ≥20/400, and moderate visual impairment (VA <20/70 but ≥20/200 were 0.6% (95% CI: 0.5-0.8, 1.3% (95% CI: 1.0-1.6, 12.6% (95% CI: 10.8-14.5. There was no significant difference among the four regions of Thailand. Cataract was the main cause of vision loss accounted for 69.7% of blindness. Cataract surgical coverage in persons was 95.1% for cut off VA of 20/400. Refractive errors, diabetic retinopathy, glaucoma, and corneal opacities were responsible for 6.0%, 5.1%, 4.0%, and 2.0% of blindness respectively. CONCLUSION: Thailand is on track to achieve the goal of VISION 2020. However, there is still much room for improvement. Policy refinements and innovative interventions are recommended to alleviate blindness and visual impairments especially regarding the backlog of blinding cataract, management of non-communicative, chronic, age-related eye diseases such as glaucoma, age-related macular degeneration, and diabetic retinopathy, prevention of childhood blindness, and establishment of a robust eye health information system.

  16. Ocular Surface Reconstruction: Recent Innovations

    OpenAIRE

    Madhavan HN

    2009-01-01

    The ocular surface is exceptionally rich in complexity and functionality. Severe ocular surface disorders/conditions, such as chemical or thermal injuries, Stevens-Johnson syndrome (SJS), ocular cicatricial pemphigoid, neurotrophic keratopathy, chronic limbitis, and severe microbial keratitis cause significant morbidities and even corneal blindness. Hypofunction may be caused by Aniridia, Neurotrophy, Endocrine, Pterygium and Chronic limbitis Approximately 6000 patients are seen in Ocular Sur...

  17. Temporal Unmixing of Dynamic Fluorescent Images by Blind Source Separation Method with a Convex Framework

    Directory of Open Access Journals (Sweden)

    Duofang Chen

    2015-01-01

    Full Text Available By recording a time series of tomographic images, dynamic fluorescence molecular tomography (FMT allows exploring perfusion, biodistribution, and pharmacokinetics of labeled substances in vivo. Usually, dynamic tomographic images are first reconstructed frame by frame, and then unmixing based on principle component analysis (PCA or independent component analysis (ICA is performed to detect and visualize functional structures with different kinetic patterns. PCA and ICA assume sources are statistically uncorrelated or independent and don’t perform well when correlated sources are present. In this paper, we deduce the relationship between the measured imaging data and the kinetic patterns and present a temporal unmixing approach, which is based on nonnegative blind source separation (BSS method with a convex analysis framework to separate the measured data. The presented method requires no assumption on source independence or zero correlations. Several numerical simulations and phantom experiments are conducted to investigate the performance of the proposed temporal unmixing method. The results indicate that it is feasible to unmix the measured data before the tomographic reconstruction and the BSS based method provides better unmixing quality compared with PCA and ICA.

  18. Blind spot detection using vision for automotive applications

    Institute of Scientific and Technical Information of China (English)

    Miguel (A)ngel SOTELO; José BARRIGA

    2008-01-01

    This paper describes a vision-based system for blind spot detection (BSD) in intelligent vehicle applications. A camera is mounted in the lateral mirror of a car with the intention of visually detecting cars that are located in the so-called blind spot and cannot be perceived by the vehicle driver. The detection of cars in the blind spot is carried out using computer vision techniques,based on optical flow and a double-stage data clustering technique for robust vehicle detection.

  19. A Proxy Blind Signature Scheme Based on ECDLP

    Institute of Scientific and Technical Information of China (English)

    WANGHaiyan; WANGRuchuan

    2005-01-01

    While proxy signature scheme enables an original signer to fully authorize a proxy to sign a message on his or her behalf legally and undeniably, blind signature scheme keeps the message blind from the signer so that the signer cannot make a linkage between the signature and the identity of requester (receiver). Both schemes have been widely applied in the electronic business. A new ECDLP (Elliptic curve discrete problem)-based proxy blind signature scheme is to be proposed in this paper by integrating the security properties of both schemes.

  20. Recurrent Bilateral Occipital Infarct with Cortical Blindness and Anton Syndrome

    Directory of Open Access Journals (Sweden)

    Kiu Kwong Yew

    2014-01-01

    Full Text Available Bilateral cortical blindness and Anton syndrome, are most commonly caused by ischaemic stroke. In this condition, patients have loss of vision but deny their blindness despite objective evidence of visual loss. We report a case of a patient with multiple cardiovascular risk factors who developed recurrent bilateral occipital lobe infarct with Anton syndrome. A suspicion of this condition should be raised when the patient has denial of blindness in the presence of clinical and radiological evidence of occipital lobe injury. Management of this condition should focus on the underlying cause, in which our patient requires secondary stroke prevention and rehabilitation.

  1. Scan blindness in infinite phased arrays of printed dipoles

    Science.gov (United States)

    Pozar, D. M.; Schaubert, D. H.

    1984-01-01

    A comprehensive study of infinite phased arrays of printed dipole antennas is presented, with emphasis on the scan blindness phenomenon. A rigorous and efficient moment method procedure is used to calculate the array impedance versus scan angle. Data are presented for the input reflection coefficient for various element spacings and substrate parameters. A simple theory, based on coupling from Floquet modes to surface wave modes on the substrate, is shown to predict the occurrence of scan blindness. Measurements from a waveguide simulator of a blindness condition confirm the theory.

  2. A Blind Detection Algorithm Utilizing Statistical Covariance in Cognitive Radio

    Directory of Open Access Journals (Sweden)

    Yingxue Li

    2012-11-01

    Full Text Available As the expression of performance parameters are obtained using asymptotic method in most blind covariance detection algorithm, the paper presented a new blind detection algorithm using cholesky factorization. Utilizing random matrix theory, we derived the performance parameters using non-asymptotic method. The proposed method overcomes the noise uncertainty problem and performs well without any information about the channel, primary user and noise. Numerical simulation results demonstrate that the performance parameters expressions are correct and the new detector outperforms the other blind covariance detectors.

  3. Gender-Blind Sexism and Rape Myth Acceptance.

    Science.gov (United States)

    Stoll, Laurie Cooper; Lilley, Terry Glenn; Pinter, Kelly

    2017-01-01

    The purpose of this article is to explore whether gender-blind sexism, as an extension of Bonilla-Silva's racialized social system theory, is an appropriate theoretical framework for understanding the creation and continued prevalence of rape myth acceptance. Specifically, we hypothesize that individuals who hold attitudes consistent with the frames of gender-blind sexism are more likely to accept common rape myths. Data for this article come from an online survey administered to the entire undergraduate student body at a large Midwestern institution (N = 1,401). Regression analysis showed strong support for the effects of gender-blind sexism on rape myth acceptance.

  4. Recurrent bilateral occipital infarct with cortical blindness and anton syndrome.

    Science.gov (United States)

    Kwong Yew, Kiu; Abdul Halim, Sanihah; Liza-Sharmini, Ahmad Tajudin; Tharakan, John

    2014-01-01

    Bilateral cortical blindness and Anton syndrome, are most commonly caused by ischaemic stroke. In this condition, patients have loss of vision but deny their blindness despite objective evidence of visual loss. We report a case of a patient with multiple cardiovascular risk factors who developed recurrent bilateral occipital lobe infarct with Anton syndrome. A suspicion of this condition should be raised when the patient has denial of blindness in the presence of clinical and radiological evidence of occipital lobe injury. Management of this condition should focus on the underlying cause, in which our patient requires secondary stroke prevention and rehabilitation.

  5. A Novel Stochastic Blind Adaptive Multiuser Detector for CDMA Systems

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Blind adaptive multiuser detector has become a research hotspot in recent years due to a number of advantages, but many blind adaptive algorithms involve low convergence rate. This paper presents a novel stochastic blind adaptive multiuser detector without requiring training sequences, which needs only two system parameters: the signature sequence of the desired user i, si and the variance of the additive white Gaussian noise (AWGN),σ2. Simulation results show that by reasonably choosing time varying step size, the proposed detector can not only improve the convergence rate, but also reduce the limiting NSE (Normalized Squared Error) values, so it can effectively increase the performance of the system.

  6. A novel data processing technique for image reconstruction of penumbral imaging

    Science.gov (United States)

    Xie, Hongwei; Li, Hongyun; Xu, Zeping; Song, Guzhou; Zhang, Faqiang; Zhou, Lin

    2011-06-01

    CT image reconstruction technique was applied to the data processing of the penumbral imaging. Compared with other traditional processing techniques for penumbral coded pinhole image such as Wiener, Lucy-Richardson and blind technique, this approach is brand new. In this method, the coded aperture processing method was used for the first time independent to the point spread function of the image diagnostic system. In this way, the technical obstacles was overcome in the traditional coded pinhole image processing caused by the uncertainty of point spread function of the image diagnostic system. Then based on the theoretical study, the simulation of penumbral imaging and image reconstruction was carried out to provide fairly good results. While in the visible light experiment, the point source of light was used to irradiate a 5mm×5mm object after diffuse scattering and volume scattering. The penumbral imaging was made with aperture size of ~20mm. Finally, the CT image reconstruction technique was used for image reconstruction to provide a fairly good reconstruction result.

  7. Outage analysis of blind cooperative diversity

    KAUST Repository

    Tourki, Kamel

    2011-06-06

    Mobile users with single antennas can still take advantage of spatial diversity through cooperative space-time-encoded transmission. In this paper, we considered a scheme in which a relay chooses to cooperate only if its source-relay channel is of an acceptable quality, and we evaluate the usefulness of relaying when the source acts blindly and ignores the decision of the relays whether they may cooperate or not. In our study, we consider the regenerative relays in which the decisions to cooperate are based on a targeted end-to-end data rate R. We derived the end-to-end outage probability for a transmission rate R and a code rate ρ and look at a power allocation strategy between the source and the relays in order to minimize the end-to-end outage probability at the destination for high signal-to-noise ratio, by using the golden section search method. Performance results show that the computer simulations-based results coincide with our analytical results. Copyright © 2011 John Wiley & Sons, Ltd.

  8. A Blind Test of Hapke's Photometric Model

    Science.gov (United States)

    Helfenstein, P.; Shepard, M. K.

    2003-01-01

    Hapke's bidirectional reflectance equation is a versatile analytical tool for predicting (i.e. forward modeling) the photometric behavior of a particulate surface from the observed optical and structural properties of its constituents. Remote sensing applications of Hapke s model, however, generally seek to predict the optical and structural properties of particulate soil constituents from the observed photometric behavior of a planetary surface (i.e. inverse-modeling). Our confidence in the latter approach can be established only if we ruthlessly test and optimize it. Here, we summarize preliminary results from a blind-test of the Hapke model using laboratory measurements obtained with the Bloomsburg University Goniometer (B.U.G.). The first author selected eleven well-characterized powder samples and measured the spectrophotometric behavior of each. A subset of twenty undisclosed examples of the photometric measurement sets were sent to the second author who fit the data using the Hapke model and attempted to interpret their optical and mechanical properties from photometry alone.

  9. Consumers' choice-blindness to ingredient information.

    Science.gov (United States)

    Cheung, T T L; Junghans, A F; Dijksterhuis, G B; Kroese, F; Johansson, P; Hall, L; De Ridder, D T D

    2016-11-01

    Food manufacturers and policy makers have been tailoring food product ingredient information to consumers' self-reported preference for natural products and concerns over food additives. Yet, the influence of this ingredient information on consumers remains inconclusive. The current study aimed at examining the first step in such influence, which is consumers' attention to ingredient information on food product packaging. Employing the choice-blindness paradigm, the current study assessed whether participants would detect a covertly made change to the naturalness of ingredient list throughout a product evaluation procedure. Results revealed that only few consumers detected the change on the ingredient lists. Detection was improved when consumers were instructed to judge the naturalness of the product as compared to evaluating the product in general. These findings challenge consumers' self-reported use of ingredient lists as a source of information throughout product evaluations. While most consumers do not attend to ingredient information, this tendency can be slightly improved by prompting their consideration of naturalness. Future research should investigate the reasons for consumers' inattention to ingredient information and develop more effective strategies for conveying information to consumers.

  10. [Educative game on drugs for blind individuals: development and assessment].

    Science.gov (United States)

    Mariano, Monaliza Ribeiro; Rebouças, Cristiana Brasil de Almeida; Pagliuca, Lorita Marlena Freitag

    2013-08-01

    Study aimed to develop and assess an educational game on psychoactive drugs accessible to blind individuals, conducted in three steps: development of the educative game, evaluation by three special education experts, and assessment by twelve blind individuals. As a result, a board game called Drugs: staying clean was developed. In the Alpha version, experts made suggestions regarding the game rules and instructions and the board base, including square texture, game pieces, and Braille writing. In Beta version, we proceeded to the assessment by the blind participants, who suggested changes in the square texture and the addition of Velcro-type material to fix the counters on the board. Then, the Gamma version was played by the last pairs of blind players and was considered by them to be adequate. In the evaluation of the experts, the game was appropriate, as it allowed access to information on psychoactive drugs in a ludic and playful manner.

  11. Find Services for People Who Are Blind or Visually Impaired

    Science.gov (United States)

    ... Programs & Services Technology Evaluation Center on Vision Loss eLearning Center Professional Development Public Policy Center Our Family ... of Visual Impairment & Blindness Center on Vision Loss eLearning Center Contact Us 2 Penn Plaza, Suite 1102 ...

  12. Crossmodal recruitment of the ventral visual stream in congenital blindness

    DEFF Research Database (Denmark)

    Ptito, Maurice; Matteau, Isabelle; Zhi Wang, Arthur

    2012-01-01

    We used functional MRI (fMRI) to test the hypothesis that blind subjects recruit the ventral visual stream during nonhaptic tactile-form recognition. Congenitally blind and blindfolded sighted control subjects were scanned after they had been trained during four consecutive days to perform...... a tactile-form recognition task with the tongue display unit (TDU). Both groups learned the task at the same rate. In line with our hypothesis, the fMRI data showed that during nonhaptic shape recognition, blind subjects activated large portions of the ventral visual stream, including the cuneus, precuneus......, inferotemporal (IT), cortex, lateral occipital tactile vision area (LOtv), and fusiform gyrus. Control subjects activated area LOtv and precuneus but not cuneus, IT and fusiform gyrus. These results indicate that congenitally blind subjects recruit key regions in the ventral visual pathway during nonhaptic...

  13. Neural correlates of virtual route recognition in congenital blindness

    DEFF Research Database (Denmark)

    Kupers, Ron; Chebat, Daniel R; Madsen, Kristoffer H

    2010-01-01

    Despite the importance of vision for spatial navigation, blind subjects retain the ability to represent spatial information and to move independently in space to localize and reach targets. However, the neural correlates of navigation in subjects lacking vision remain elusive. We therefore used...... functional MRI (fMRI) to explore the cortical network underlying successful navigation in blind subjects. We first trained congenitally blind and blindfolded sighted control subjects to perform a virtual navigation task with the tongue display unit (TDU), a tactile-to-vision sensory substitution device...... that translates a visual image into electrotactile stimulation applied to the tongue. After training, participants repeated the navigation task during fMRI. Although both groups successfully learned to use the TDU in the virtual navigation task, the brain activation patterns showed substantial differences. Blind...

  14. Morphometric changes of the corpus callosum in congenital blindness

    DEFF Research Database (Denmark)

    Tomaiuolo, Francesco; Campana, Serena; Collins, D Louis

    2014-01-01

    We examined the effects of visual deprivation at birth on the development of the corpus callosum in a large group of congenitally blind individuals. We acquired high-resolution T1-weighted MRI scans in 28 congenitally blind and 28 normal sighted subjects matched for age and gender....... There was no overall group effect of visual deprivation on the total surface area of the corpus callosum. However, subdividing the corpus callosum into five subdivisions revealed significant regional changes in its three most posterior parts. Compared to the sighted controls, congenitally blind individuals showed a 12......% reduction in the splenium, and a 20% increase in the isthmus and the posterior part of the body. A shape analysis further revealed that the bending angle of the corpus callosum was more convex in congenitally blind compared to the sighted control subjects. The observed morphometric changes in the corpus...

  15. CROSS-MODAL PLASTICITY OF TACTILE PERCEPTION IN BLINDNESS

    Science.gov (United States)

    Sathian, K.; Stilla, Randall

    2011-01-01

    This review focusses on cross-modal plasticity resulting from visual deprivation. This is viewed against the background of task-specific visual cortical recruitment that is routine during tactile tasks in the sighted and that may depend in part on visual imagery. Superior tactile perceptual performance in the blind may be practice-related, although there are unresolved questions regarding the effects of Braille-reading experience and the age of onset of blindness. While visual cortical areas are clearly more involved in tactile microspatial processing in the blind than in the sighted, it still remains unclear how to reconcile these tactile processes with the growing literature implicating visual cortical activity in a wide range of cognitive tasks in the blind, including those involving language, or with studies of short-term, reversible visual deprivation in the normally sighted that reveal plastic changes even over periods of hours or days. PMID:20404414

  16. Psychological Disorders of Blind Persons and Success in Residential Rehabilitation.

    Science.gov (United States)

    Needham, W. E.; And Others

    1992-01-01

    Comparison of residential rehabilitation outcomes of blind clients with (n=45) or without (n=67) previous psychiatric diagnosis found no intergroup differences after rehabilitation in skill, attitude, and overall adjustment. All clients improved significantly during rehabilitation. (DB)

  17. Sociodrama: strategy for nurses’ self-reflection on blindness

    Directory of Open Access Journals (Sweden)

    Inacia Sátiro Xavier de França

    2016-01-01

    Full Text Available Objective: to investigate the master students’ expressions about feelings, difficulties and challenges arising from participation in sociodrama “as if” they were blind. Methods: qualitative study. Participants were eight Master students in nursing. They used sociodrama, a video recorder and the Content Analysis technique. In implementing the sociodrama, the steps were followed were warm-up, drama, comments and theoretical processing. Results: the following thematic categories emerged: the role as blind person triggering limitation, blocking and fear; the role as blind person triggering a confused notion of one’s own body; spontaneity and creativity expressed by Master students. Conclusion: the Master students expressed the feeling of fear to walking in an environment with which they were already familiar, had difficulty in eating because of the confused notion of their own body, and could reflect on the challenge of caring for the blind person, because they realized that they were professionally unprepared to take care of these individuals.

  18. Neural correlates of olfactory processing in congenital blindness

    DEFF Research Database (Denmark)

    Kupers, R; Beaulieu-Lefebvre, M; Schneider, F C

    2011-01-01

    Adaptive neuroplastic changes have been well documented in congenitally blind individuals for the processing of tactile and auditory information. By contrast, very few studies have investigated olfactory processing in the absence of vision. There is ample evidence that the olfactory system...... is highly plastic and that blind individuals rely more on their sense of smell than the sighted do. The olfactory system in the blind is therefore likely to be susceptible to cross-modal changes similar to those observed for the tactile and auditory modalities. To test this hypothesis, we used functional....... The stronger recruitment of the occipital cortex during odor detection demonstrates a preferential access of olfactory stimuli to this area when vision is lacking from birth. This finding expands current knowledge about the supramodal function of the visually deprived occipital cortex in congenital blindness...

  19. Experimental Contact Lens to Prevent Glaucoma-Induced Blindness

    Science.gov (United States)

    ... Home Page An Experimental Contact Lens to Prevent Glaucoma-Induced Blindness By Sharon Reynolds Posted January 23, 2014 An experimental contact lens design releases a glaucoma medicine at a steady rate for up to ...

  20. Thermal blinding of gated detectors in quantum cryptography.

    Science.gov (United States)

    Lydersen, Lars; Wiechers, Carlos; Wittmann, Christoffer; Elser, Dominique; Skaar, Johannes; Makarov, Vadim

    2010-12-20

    It has previously been shown that the gated detectors of two commercially available quantum key distribution (QKD) systems are blindable and controllable by an eavesdropper using continuous-wave illumination and short bright trigger pulses, manipulating voltages in the circuit [Nat. Photonics 4, 686 (2010)]. This allows for an attack eavesdropping the full raw and secret key without increasing the quantum bit error rate (QBER). Here we show how thermal effects in detectors under bright illumination can lead to the same outcome. We demonstrate that the detectors in a commercial QKD system Clavis2 can be blinded by heating the avalanche photo diodes (APDs) using bright illumination, so-called thermal blinding. Further, the detectors can be triggered using short bright pulses once they are blind. For systems with pauses between packet transmission such as the plug-and-play systems, thermal inertia enables Eve to apply the bright blinding illumination before eavesdropping, making her more difficult to catch.

  1. Network reconstruction from infection cascades

    CERN Document Server

    Braunstein, Alfredo

    2016-01-01

    Reconstructing propagation networks from observations is a fundamental inverse problem, and it's crucial to understand and control dynamics in complex systems. Here we show that it is possible to reconstruct the whole structure of an interaction network and to simultaneously infer the complete time course of activation spreading, relying just on single snapshots of a small number of activity cascades. The method, that we called Inverse Dynamics Network Reconstruction (IDNR), is shown to work successfully on several synthetic and real networks, inferring the networks and the sources of infection based on sparse observations, including single snapshots. IDNR is built on a Belief Propagation approximation, that has an impressive performance in a wide variety of topological structures. The method can be applied in absence of complete time-series data by providing a detailed modeling of the posterior distribution of trajectories conditioned to the observations. Furthermore, we show by experiments that the informat...

  2. Track Reconstruction Performance in CMS

    CERN Document Server

    Azzurri, Paolo

    2008-01-01

    The expected performance of track reconstruction with LHC events using the CMS silicon tracker is presented. Track finding and fitting is accomplished with Kalman Filter techniques that achieve efficiencies above 99\\% on single muons with $p_T >$1~GeV/c. Difficulties arise in the context of standard LHC events with a high density of charged particles, where the rate of fake combinatorial tracks is very large for low $p_T$ tracks, and nuclear interactions in the tracker material reduce the tracking efficiency for charged hadrons. Recent improvements with the CMS track reconstruction now allow to efficiently reconstruct charged tracks with $p_T$ down to few hundred MeV/c and as few as three crossed layers, with a very small fake fraction, by making use of an optimal rejection of fake tracks in conjunction with an iterative tracking procedure.

  3. CURRENT CONCEPTS IN ACL RECONSTRUCTION

    Directory of Open Access Journals (Sweden)

    Freddie H. Fu

    2008-09-01

    Full Text Available Current Concepts in ACL Reconstruction is a complete reference text composed of the most thorough collection of topics on the ACL and its surgical reconstruction compiled, with contributions from some of the world's experts and most experienced ACL surgeons. Various procedures mentioned throughout the text are also demonstrated in an accompanying video CD-ROM. PURPOSE Composing a single, comprehensive and complete information source on ACL including basic sciences, clinical issues, latest concepts and surgical techniques, from evaluation to outcome, from history to future, editors and contributors have targeted to keep the audience pace with the latest concepts and techniques for the evaluation and the treatment of ACL injuries. FEATURES The text is composed of 27 chapters in 6 sections. The first section is mostly about basic sciences, also history of the ACL, imaging, clinical approach to adolescent and pediatric patients are subjected. In the second section, Graft Choices and Arthroscopy Portals for ACL Reconstruction are mentioned. The third section is about the technique and the outcome of the single-bundle ACL reconstruction. The fourth chapter includes the techniques and outcome of the double-bundle ACL reconstruction. In the fifth chapter revision, navigation technology, rehabilitation and the evaluation of the outcome of ACL reconstruction is subjected. The sixth/the last chapter is about the future advances to reach: What We Have Learned and the Future of ACL Reconstruction. AUDIENCE Orthopedic residents, sports traumatology and knee surgery fellows, orthopedic surgeons, also scientists in basic sciences or clinicians who are studying or planning a research on ACL forms the audience group of this book. ASSESSMENT This is the latest, the most complete and comprehensive textbook of ACL reconstruction produced by the editorial work up of two pioneer and masters "Freddie H. Fu MD and Steven B. Cohen MD" with the contribution of world

  4. Altered myoelectric activity in the experimental blind loop syndrome.

    Science.gov (United States)

    Justus, P G; Fernandez, A; Martin, J L; King, C E; Toskes, P P; Mathias, J R

    1983-09-01

    Nutrient malabsorption and diarrhea are characteristic of the blind loop syndrome. Alterations in motility have been implicated as a cause of bacterial overgrowth, but the possibility that altered motility may result from alterations in the flora has not been explored. The purpose of this study was to characterize the myoelectric activity of the small intestine in the blind loop rat model. Eight groups of rats were studied: rats with self-filling blind loops, which develop bacterial overgrowth; rats with self-emptying blind loops, which are surgical controls that do not develop overgrowth; unoperated litter mates; rats with self-filling blind loops and unoperated controls treated with chloramphenicol, 200 mg/d i.p.; rats with surgically removed self-filling blind loops; operated control rats; and gnotobiotic rats with self-filling blind loops. In the untreated rats with self-filling blind loops, there was altered myoelectric activity characterized by an increased percentage of slow waves occupied by action potentials and by organized activity similar to the migrating action potential complex. Migrating action potential complex activity and percentage of slow waves occupied by action potentials were significantly decreased with chloramphenicol therapy; that decrease correlated with a decrease in aerobes and anaerobes. Migrating action potential complex activity was abolished in rats with surgically removed self-filling blind loops; they also showed a significant decrease in percentage of slow waves occupied by action potentials. Gnotobiotic rats with self-filling blind loops showed no alteration in myoelectric activity. These data indicate: (a) bacterial overgrowth is associated with a significant increase in percentage of slow waves occupied by action potentials and migrating action potential complex activity; (b) chloramphenicol significantly reduced both percentage of slow waves occupied by action potentials and migrating action potential complex activity; and (c

  5. 34 CFR 395.33 - Operation of cafeterias by blind vendors.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Operation of cafeterias by blind vendors. 395.33... BLIND ON FEDERAL AND OTHER PROPERTY Federal Property Management § 395.33 Operation of cafeterias by blind vendors. (a) Priority in the operation of cafeterias by blind vendors on Federal property shall...

  6. Perspectiva General sobre la Sordo-Ceguera (Overview on Deaf-Blindness). DB-LINK.

    Science.gov (United States)

    Miles, Barbara

    This overview provides basic information on the causes of deaf-blindness and the particular challenges faced by individuals who are deaf-blind. Causes of deaf-blindness include various syndromes, multiple congenital anomalies, prematurity, congenital prenatal dysfunction, and various postnatal causes. Differences between people deaf-blind from…

  7. A note on parallel executions of restrictive blind issuing protocols for secret-key certificates

    NARCIS (Netherlands)

    Brands, S.A.

    1995-01-01

    The receiver in a restrictive blind certificate issuing protocol can blind the issued public key and the certificate but not a certain blinding-invariant predicate of the secret key. Recently a generally applicable technique was described for designing restrictive blind issuing protocols for a certa

  8. Autism Spectrum Disorders (ASD) in Blind Children: Very High Prevalence, Potentially Better Outlook

    Science.gov (United States)

    Jure, Rubin; Pogonza, Ramón; Rapin, Isabelle

    2016-01-01

    Autism spectrum disorders affected 19 of 38 unselected children at a school for the blind in Cordoba, Argentina. Autism was linked to total congenital blindness, not blindness' etiology, acquired or incomplete blindness, sex, overt brain damage, or socioeconomic status. Autism "recovery," had occurred in 4 verbal children. Congenital…

  9. Blindness, art and exclusion in museums and galleries

    OpenAIRE

    Candlin, Fiona

    2003-01-01

    Drawing on interviews with blind people, this paper examines both their exclusion from museums and galleries and their responses to the art educational provision which is specifically designed to remedy that marginalisation. Blind visitors’ responses to these educational projects was polarised; respondents were either highly critical or very enthusiastic. This paper begins by outlining the interviewees’ criticisms which included, education officers’ misconception of how touch facilitates lear...

  10. A Collaborative Writing Mode for Avoiding Blind Modifications

    OpenAIRE

    Ignat, Claudia,; Oster, Gérald; Molli, Pascal; Skaf-Molli, Hala

    2007-01-01

    International audience; Existing collaborative environments such as Wiki or version control systems allow users to work in isolation, but they do not prevent blind modifications. For instance, users may concurrently perform the same task or they might work on obsolete versions of shared documents. We propose a novel writing mode for avoiding blind modifications by providing real-time information about group activities. Changes performed concurrently are filtered according to user privacy pref...

  11. Virtual environment interaction through 3D audio by blind children.

    Science.gov (United States)

    Sánchez, J; Lumbreras, M

    1999-01-01

    Interactive software is actively used for learning, cognition, and entertainment purposes. Educational entertainment software is not very popular among blind children because most computer games and electronic toys have interfaces that are only accessible through visual cues. This work applies the concept of interactive hyperstories to blind children. Hyperstories are implemented in a 3D acoustic virtual world. In past studies we have conceptualized a model to design hyperstories. This study illustrates the feasibility of the model. It also provides an introduction to researchers to the field of entertainment software for blind children. As a result, we have designed and field tested AudioDoom, a virtual environment interacted through 3D Audio by blind children. AudioDoom is also a software that enables testing nontrivial interfaces and cognitive tasks with blind children. We explored the construction of cognitive spatial structures in the minds of blind children through audio-based entertainment and spatial sound navigable experiences. Children playing AudioDoom were exposed to first person experiences by exploring highly interactive virtual worlds through the use of 3D aural representations of the space. This experience was structured in several cognitive tasks where they had to build concrete models of their spatial representations constructed through the interaction with AudioDoom by using Legotrade mark blocks. We analyze our preliminary results after testing AudioDoom with Chilean children from a school for blind children. We discuss issues such as interactivity in software without visual cues, the representation of spatial sound navigable experiences, and entertainment software such as computer games for blind children. We also evaluate the feasibility to construct virtual environments through the design of dynamic learning materials with audio cues.

  12. Transient cortical blindness after thoracic endovascular aneurysm repair.

    Science.gov (United States)

    Vallabhaneni, Raghuveer; Jim, Jeffrey; Derdeyn, Colin P; Sanchez, Luis A

    2011-05-01

    We report a patient who presented with transient cortical blindness 12 hours after completion of a thoracic endovascular aneurysm repair. Computed tomography of the brain demonstrated no acute findings. The patient's symptoms resolved spontaneously after 72 hours. To our knowledge, this is the first report of transient cortical blindness after endovascular aortic aneurysm repair. This is an uncommon diagnosis that is important to recognize in a modern vascular surgery practice.

  13. Blind loop syndrome: an unusual cause of panniculitis.

    Science.gov (United States)

    Caux, F; Halimi, C; Kevorkian, J P; Pinquier, L; Dubertret, L; Segrestaa, J M

    1997-11-01

    We describe a 52-year-old woman with panniculitis and blind loop syndrome. She had undergone a gastrectomy for peptic ulcer 4 years before. Tender erythematous nodules on her palms and soles were associated with diarrhea and weight loss. A biopsy specimen revealed septal and lobular panniculitis. A glucose hydrogen breath test was consistent with bacterial overgrowth. These results were consistent with panniculitis associated with a blind loop syndrome. Only four cases of this association have been reported previously.

  14. Spot Rare Occurrences More Frequently by Lessening Inattentional Blindness

    Science.gov (United States)

    2013-04-29

    FINCH, U. and LAVIE , N. 2007. The role of perceptual load in inattentional blindness. Cognition 102 (2007), 321–340. DOI 10.1016/j.cognition... LAVIE , N. 2008. Load induced blindness. Journal of Experimental Psychology: Human Perception and Performance. 34 (5), 1078-1091. DOI: 10.1037/0096...2011.09.013 RODA, C. and THOMAS, J. 2006. Attention Aware Systems: Theory , Application, and Research Agenda. Computers in Human Behavior," Computers in Human

  15. Clinical applications of iterative reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Eberl, S. [Royal Prince Alfred Hospital, Camperdown, NSW (Australia). Department of PET and Nuclear Medicine

    1998-03-01

    Expectation maximisation (EM) reconstruction largely eliminates the hot and cold streaking artifacts characteristic of filtered-back projection (FBP) reconstruction around localised hot areas, such as the bladder. It also substantially reduces the problem of decreased inferior wall counts in MIBI myocardial perfusion studies due to ``streaking`` from high liver uptake. Non-uniform attenuation and scatter correction, resolution recovery, anatomical information, e.g. from MRI or CT tracer kinetic modelling, can all be built into the EM reconstruction imaging model. The properties of ordered subset EM (OSEM) have also been used to correct for known patient motion as part of the reconstruction process. These uses of EM are elaborated more fully in some of the other abstracts of this meeting. Currently we use OSEM routinely for: (i) studies where streaking is a problem, including all MIBI myocardial perfusion studies, to avoid hot liver inferior wall artifact, (ii) all whole body FDG PET, all lung V/Q SPECT (which have a short acquisition time) and all gated {sup 201}TI myocardial perfusion studies due to improved noise characteristics of OSEM in these studies; (iii) studies with measured, non-uniform attenuation correction. With the accelerated OSEM algorithm, iterative reconstruction is practical for routine clinical applications and we have found OSEM to provide clearly superior reconstructions for the areas listed above and are investigating its application to other studies. In clinical use, we have not found OSEM to introduce artifacts which would not also occur with FBP, e.g. uncorrected patient motion will cause artifacts with both OSEM and FBP.

  16. Markov Random Field Surface Reconstruction

    DEFF Research Database (Denmark)

    Paulsen, Rasmus Reinhold; Bærentzen, Jakob Andreas; Larsen, Rasmus

    2010-01-01

    ) and knowledge about data (the observation model) in an orthogonal fashion. Local models that account for both scene-specific knowledge and physical properties of the scanning device are described. Furthermore, how the optimal distance field can be computed is demonstrated using conjugate gradients, sparse......A method for implicit surface reconstruction is proposed. The novelty in this paper is the adaption of Markov Random Field regularization of a distance field. The Markov Random Field formulation allows us to integrate both knowledge about the type of surface we wish to reconstruct (the prior...

  17. Tragal reconstruction after tumor excision.

    Science.gov (United States)

    Coombs, Christopher J; Lin, Frank

    2015-02-01

    The tragus forms a distinct and important landmark in the overall artistic and anatomical landscape of the ear. Despite its small size, it functions to cover and prevent direct access to the ear canal. Aesthetically, it has an important role in defining the morphology of the auricle in 3 dimensions, not only covering the meatus but also casting a shadow into the conchal bowl that gives the impression of depth. Most of the techniques for tragal reconstruction are associated with creation of a tragus in patients with microtia. We present here a new technique for tragal reconstruction in the setting of tumor ablation.

  18. Vascular Reconstruction in Hepatic Malignancy.

    Science.gov (United States)

    Berumen, Jennifer; Hemming, Alan

    2016-04-01

    With surgery for hepatic malignancy, there are poor options for chemotherapy; many patients are deemed unresectable because of vascular involvement or location of tumors. Over the past few decades, advances in surgical technique have allowed resection of these tumors with vascular reconstruction to achieve negative margins and improve chances for survival. This article reviews those reconstruction techniques and outcomes in detail, including in situ perfusion and ex vivo liver surgery, and provides a discussion of implications and operative planning for patients with hepatic malignancy in order to provide surgeons with better understanding of these complicated operations.

  19. Rational Reconstructions of Modern Physics

    CERN Document Server

    Mittelstaedt, Peter

    2011-01-01

    Newton’s classical physics and its underlying ontology are loaded with several metaphysical hypotheses that cannot be justified by rational reasoning nor by experimental evidence. Furthermore, it is well known that some of these hypotheses are not contained in the great theories of modern physics, such as the theory of relativity and quantum mechanics. This book shows that, on the basis of Newton’s classical physics and by rational reconstruction, the theory of relativity as well as quantum mechanics can be obtained by partly eliminating or attenuating the metaphysical hypotheses. Moreover, it is shown that these reconstructions do not require additional hypotheses or new experimental results.

  20. Computed tomography depiction of small pediatric vessels with model-based iterative reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Koc, Gonca; Courtier, Jesse L.; Phelps, Andrew; Marcovici, Peter A.; MacKenzie, John D. [UCSF Benioff Children' s Hospital, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States)

    2014-07-15

    Computed tomography (CT) is extremely important in characterizing blood vessel anatomy and vascular lesions in children. Recent advances in CT reconstruction technology hold promise for improved image quality and also reductions in radiation dose. This report evaluates potential improvements in image quality for the depiction of small pediatric vessels with model-based iterative reconstruction (Veo trademark), a technique developed to improve image quality and reduce noise. To evaluate Veo trademark as an improved method when compared to adaptive statistical iterative reconstruction (ASIR trademark) for the depiction of small vessels on pediatric CT. Seventeen patients (mean age: 3.4 years, range: 2 days to 10.0 years; 6 girls, 11 boys) underwent contrast-enhanced CT examinations of the chest and abdomen in this HIPAA compliant and institutional review board approved study. Raw data were reconstructed into separate image datasets using Veo trademark and ASIR trademark algorithms (GE Medical Systems, Milwaukee, WI). Four blinded radiologists subjectively evaluated image quality. The pulmonary, hepatic, splenic and renal arteries were evaluated for the length and number of branches depicted. Datasets were compared with parametric and non-parametric statistical tests. Readers stated a preference for Veo trademark over ASIR trademark images when subjectively evaluating image quality criteria for vessel definition, image noise and resolution of small anatomical structures. The mean image noise in the aorta and fat was significantly less for Veo trademark vs. ASIR trademark reconstructed images. Quantitative measurements of mean vessel lengths and number of branches vessels delineated were significantly different for Veo trademark and ASIR trademark images. Veo trademark consistently showed more of the vessel anatomy: longer vessel length and more branching vessels. When compared to the more established adaptive statistical iterative reconstruction algorithm, model

  1. Neural correlates of taste perception in congenital blindness.

    Science.gov (United States)

    Gagnon, L; Kupers, R; Ptito, M

    2015-04-01

    Sight is undoubtedly important for the perception and the assessment of the palatability of tastants. Although many studies have addressed the consequences of visual impairment on food selection, feeding behavior, eating habits and taste perception, nothing is known about the neural correlates of gustation in blindness. In the current study we examined brain responses during gustation using functional magnetic resonance imaging (fMRI). We scanned nine congenitally blind and 14 age- and sex-matched blindfolded sighted control subjects, matched in age, gender and body mass index (BMI), while they made judgments of either the intensity or the (un)pleasantness of different tastes (sweet, bitter) or artificial saliva that were delivered intra-orally. The fMRI data indicated that during gustation, congenitally blind individuals activate less strongly the primary taste cortex (right posterior insula and overlying Rolandic operculum) and the hypothalamus. In sharp contrast with results of multiple other sensory processing studies in congenitally blind subjects, including touch, audition and smell, the occipital cortex was not recruited during taste processing, suggesting the absence of taste-related compensatory crossmodal responses in the occipital cortex. These results underscore our earlier behavioral demonstration that congenitally blind subjects have a lower gustatory sensitivity compared to normal sighted individuals. We hypothesize that due to an underexposure to a variety of tastants, training-induced crossmodal sensory plasticity to gustatory stimulation does not occur in blind subjects.

  2. Blinding in randomized control trials: the enigma unraveled.

    Directory of Open Access Journals (Sweden)

    Vartika Saxena

    2016-03-01

    Full Text Available The search for new treatments and testing of new ideas begins in the laboratory and then established in clinical research settings. Studies addressing the same therapeutic problem may produce conflicting results hence Randomised Clinical Trial is regarded as the most valid method for assessing the benefits and harms of healthcare interventions. The next challenge face by the medical community is the validity of such trials as theses tend to deviate from the truth because of various biases. For the avoidance of the same it has been suggested that the validity or quality of primary trials should be assessed under blind conditions. Thus blinding, is a crucial method for reducing bias in randomized clinical trials. Blinding can be defined as withholding information about the assigned interventions from people involved in the trial who may potentially be prejudiced by this knowledge. In this article we make an effort to define blinding, explain its chronology, hierarchy and discuss methods of blinding, its assessment, its possibility, un-blinding and finally the latest guidelines.

  3. Cognitive sophistication does not attenuate the bias blind spot.

    Science.gov (United States)

    West, Richard F; Meserve, Russell J; Stanovich, Keith E

    2012-09-01

    The so-called bias blind spot arises when people report that thinking biases are more prevalent in others than in themselves. Bias turns out to be relatively easy to recognize in the behaviors of others, but often difficult to detect in one's own judgments. Most previous research on the bias blind spot has focused on bias in the social domain. In 2 studies, we found replicable bias blind spots with respect to many of the classic cognitive biases studied in the heuristics and biases literature (e.g., Tversky & Kahneman, 1974). Further, we found that none of these bias blind spots were attenuated by measures of cognitive sophistication such as cognitive ability or thinking dispositions related to bias. If anything, a larger bias blind spot was associated with higher cognitive ability. Additional analyses indicated that being free of the bias blind spot does not help a person avoid the actual classic cognitive biases. We discuss these findings in terms of a generic dual-process theory of cognition.

  4. Space and time in the sighted and blind.

    Science.gov (United States)

    Bottini, Roberto; Crepaldi, Davide; Casasanto, Daniel; Crollen, Virgine; Collignon, Olivier

    2015-08-01

    Across many cultures people conceptualize time as extending along a horizontal Mental Time Line (MTL). This spatial mapping of time has been shown to depend on experience with written text, and may also depend on other graphic conventions such as graphs and calendars. All of this information is typically acquired visually, suggesting that visual experience may play an important role in the development of the MTL. Do blind people develop a MTL? If so, how does it compare with the MTL in sighted? In this study we tested early blind, late blind and sighted participants in a space-time congruity task. Participants had to classify temporal words by pressing a right and a left key, either with crossed or uncrossed hands. We found that the MTL develops in the absence of vision, and that it is based on the same external frame of reference in sighted and blind people. Reading braille may provide the same experiential link between space and time in the manual modality as reading printed text provides in the visual modality. These results showing a similar MTL in sighted and blind participants contrast with previous results showing that the Mental Number Line (MNL) depends on different spatial coordinates in the sighted and the blind, and suggest that spatial representations of time and number may have different experiential bases.

  5. On the malleability of ideology: motivated construals of color blindness.

    Science.gov (United States)

    Knowles, Eric D; Lowery, Brian S; Hogan, Caitlin M; Chow, Rosalind M

    2009-04-01

    The authors propose that the content of certain sociopolitical ideologies can be shaped by individuals in ways that satisfy their social motivations. This notion was tested in the context of color-blind ideology. Color blindness, when construed as a principle of distributive justice, is an egalitarian stance concerned with reducing discrepancies between groups' outcomes; as a principle of procedural justice, however, color blindness can function as a legitimizing ideology that entrenches existing inequalities. In Study 1, White people high in antiegalitarian sentiment were found to shift their construal of color blindness from a distributive to a procedural principle when exposed to intergroup threat. In Studies 2, 3A, and 3B, the authors used manipulations and a measure of threat to show that antiegalitarian White people endorse color blindness to legitimize the racial status quo. In Study 3B, participants' endorsement of color-blind ideology was mediated by increases in their preference for equal treatment (i.e., procedural justice) as a response to threat. In the Discussion section, the authors examine implications of the present perspective for understanding the manner in which individuals compete over the meaning of crucial ideologies.

  6. Cataract blindness in the developing world: is there a solution?

    Science.gov (United States)

    Isaacs, Robert; Ram, Jagat; Apple, David

    2004-01-01

    Cataracts are the leading cause of blindness worldwide, accounting for half of the world's 40 million blind. The majority of the world's 20 million cataract blind live in the developing world. About 5 million new cases of cataract blindness occur each year. Only a small percentage of persons in the Third World who develop cataracts receive cataract surgery. Cataract blindness causes severe economic and social problems in these countries. Because of increased longevity and population growth in the Third World, the number of untreated cataract cases is escalating rapidly. Governmental, non-governmental and service club organizations have put extraordinary effort and resources into reversing the trend of increasing cataract blindness, but much work still needs to be done. Current surgical methods used in the Third World have not yet succeeded in reducing the backlog of cataracts, due in part to either their prohibitive cost or poor results. Extra capsular cataract extraction (ECCE) with placement of a posterior chamber intraocular lens (PC-IOL) is the hope for preferred method of treatment. This paper discusses a largely overlooked method of cataract surgery which may be an additional, cost-effective and efficacious means of providing good sight rehabilitation. Combining intracapsular cataract extraction, currently the most common method used in the rural developing world, with anterior chamber intraocular lens implantation (ICCE AC-IOL), may prove effective in reducing the cataract backlog in developing countries.

  7. Crossmodal Recruitment of the Ventral Visual Stream in Congenital Blindness

    Directory of Open Access Journals (Sweden)

    Maurice Ptito

    2012-01-01

    Full Text Available We used functional MRI (fMRI to test the hypothesis that blind subjects recruit the ventral visual stream during nonhaptic tactile-form recognition. Congenitally blind and blindfolded sighted control subjects were scanned after they had been trained during four consecutive days to perform a tactile-form recognition task with the tongue display unit (TDU. Both groups learned the task at the same rate. In line with our hypothesis, the fMRI data showed that during nonhaptic shape recognition, blind subjects activated large portions of the ventral visual stream, including the cuneus, precuneus, inferotemporal (IT, cortex, lateral occipital tactile vision area (LOtv, and fusiform gyrus. Control subjects activated area LOtv and precuneus but not cuneus, IT and fusiform gyrus. These results indicate that congenitally blind subjects recruit key regions in the ventral visual pathway during nonhaptic tactile shape discrimination. The activation of LOtv by nonhaptic tactile shape processing in blind and sighted subjects adds further support to the notion that this area subserves an abstract or supramodal representation of shape. Together with our previous findings, our data suggest that the segregation of the efferent projections of the primary visual cortex into a dorsal and ventral visual stream is preserved in individuals blind from birth.

  8. Post-anesthetic cortical blindness in cats: twenty cases.

    Science.gov (United States)

    Stiles, J; Weil, A B; Packer, R A; Lantz, G C

    2012-08-01

    The medical records of 20 cats with post-anesthetic cortical blindness were reviewed. Information collected included signalment and health status, reason for anesthesia, anesthetic protocols and adverse events, post-anesthetic visual and neurological abnormalities, clinical outcome, and risk factors. The vascular anatomy of the cat brain was reviewed by cadaver dissections. Thirteen cats were anaesthetised for dentistry, four for endoscopy, two for neutering procedures and one for urethral obstruction. A mouth gag was used in 16/20 cats. Three cats had had cardiac arrest, whereas in the remaining 17 cases, no specific cause of blindness was identified. Seventeen cats (85%) had neurological deficits in addition to blindness. Fourteen of 20 cats (70%) had documented recovery of vision, whereas four (20%) remained blind. Two cats (10%) were lost to follow up while still blind. Ten of 17 cats (59%) with neurological deficits had full recovery from neurological disease, two (12%) had mild persistent deficits and one (6%) was euthanased as it failed to recover. Four cats (23%) without documented resolution of neurological signs were lost to follow up. Mouth gags were identified as a potential risk factor for cerebral ischemia and blindness in cats.

  9. Protein digestion and absorption in the blind loop syndrome.

    Science.gov (United States)

    Curtis, K J; Prizont, R; Kim, Y S

    1979-12-01

    Protein digestion and absorption was studied in rats with 6-week-old surgically constructed self-filling intestinal blind loops and steatorrhea, ie, blind-loop animals and controls were fed a 14C-labeled protein meal containing a nonabsorbable marker, 51CrCl3, and sacrificed 1 or 2 hr later. Intestinal contents were analyzed for 14C, 51Cr, protein, trypsin, and the products of digestion. At 1 hr, 14C absorption was greater in controls, but at 2 hr there was no difference in absorption between the two groups. Marker studies showed that blind-loop filling resulted in a delay of the progression of intestinal contents distally. Intraluminal trypsin and porteolysis were similar in the two groups. Endogenous protein was greater in the blind-loop animals. The early stages of the blind-loop syndrome may be characterized by delayed protein absorption secondary to blind-loop filling, which is compensated for by the distal gut resulting in an absence of overall protein malabsorption.

  10. Attentional modulation of motion-induced blindness

    Institute of Scientific and Technical Information of China (English)

    GENG HaiYan; SONG QianLan; LI YunFeng; XU Shan; ZHU Ying

    2007-01-01

    When a global moving pattern is superimposed on high-contrast stationary or slowly moving stimuli,the stimuli can be perceived as disappearing and reappearing alternately for periods of several seconds. This visual illusory phenomenon was named "motion-induced blindness" (MIB) in recent literature. So far there is no consensus on the mechanism of MIB, especially on the role of attention in this phenomenon. To examine the effect of spatial attention on MIB, the present study manipulated the participants' spatial attention by asking them to respond to two targets simultaneously presented in bilateral visual fields (the divided-attention condition) or only respond to one of them (the focused-attention condition). A central arrow was presented as an endogenous cue to index the target visual field in the focused-attention condition, while a point was presented instead in the divided-attention condition. The results show that the percentage of accumulated invisibility period was larger for the targets in the focused-attention condition than for those in the divided-attention condition.This effect of attentionis significant in upper visual field (UVF) and left lower visual field (left LVF); that is, this effect shows a hemispheric asymmetry in LVF but not in UVF. Furthermore, the percentage of accumulated invisibility period was larger for targets in left LVF than for those in right LVF in the focused-attention condition, but no hemispheric asymmetry was found in the divided-attention condition.In addition, the increased percentage of accumulated invisibility period in the focused-attention condition originated merely in the enhancement of the mean phase duration of disappearance in LVF, while the disappearance occurred more frequently and lasted longer for each occurrence, which led to an increase in the total invisibility period, in the focused- than divided-attention condition in UVF. These results suggest that the modulation of spatial attention on MIB has different

  11. Lexical references to sensory modalities in verbal descriptions of people and objects by congenitally blind, late blind and sighted adults.

    Directory of Open Access Journals (Sweden)

    Valérie Chauvey

    Full Text Available BACKGROUND: Some previous studies have revealed that while congenitally blind people have a tendency to refer to visual attributes ('verbalism', references to auditory and tactile attributes are scarcer. However, this statement may be challenged by current theories claiming that cognition is linked to the perceptions and actions from which it derives. Verbal productions by the blind could therefore differ from those of the sighted because of their specific perceptual experience. The relative weight of each sense in oral descriptions was compared in three groups with different visual experience Congenitally blind (CB, late blind (LB and blindfolded sighted (BS adults. METHODOLOGY/PRINCIPAL FINDINGS: Participants were asked to give an oral description of their mother and their father, and of four familiar manually-explored objects. The number of visual references obtained when describing people was relatively high, and was the same in the CB and BS groups ("verbalism" in the CB. While references to touch were scarce in all groups, the CB referred to audition more frequently than the LB and the BS groups. There were, by contrast, no differences between groups in descriptions of objects, and references to touch dominated the other modalities. CONCLUSION/SIGNIFICANCE: The relative weight of each modality varies according to the cognitive processes involved in each task. Long term memory, internal representations and information acquired through social communication, are at work in the People task, seem to favour visual references in both the blind and the sighted, whereas the congenitally blind also refer often to audition. By contrast, the perceptual encoding and working memory at work in the Objects task enhance sensory references to touch in a similar way in all groups. These results attenuate the impact of verbalism in blindness, and support (albeit moderately the idea that the perceptual experience of the congenitally blind is to some extent

  12. Three Blind Men and the Elephant

    Energy Technology Data Exchange (ETDEWEB)

    Long, J S

    2007-02-13

    Just like the blind men in the popular story of perceiving the elephant, the three major constituencies participating in the energy debate have greatly different perceptions of the problem. The constituency that is worried about climate change believes the energy problem is caused by profligate use of fossil fuel that has dramatically changed our atmosphere. The energy security group sees dangerous reliance on foreign sources of oil increasingly held by countries hostile to the US. The economic vitality group sees high energy prices and their effect on the economy and our life-style. Just like the blind men, each of the three constituencies perceives a different problem. And just as with the blind men, while each perspective is right as a piece of the elephant, it takes all the perspectives together to actually solve the problem. Environmentalists focus on solutions responding to the scientific consensus that greenhouse gases are creating rapid climate change. The tipping point has come: it is now a consensus position among scientists the global warming is being affected by anthropogenic activity to 90% certainty according to the last IPCC report. Although they still struggle with the prediction of how much global temperatures will rise if we do nothing--is it 5 deg or 10 under BAU? This group believes that we cannot afford to take a chance because we get only one chance. We can not afford to do this kind of experiment with the Earth. Any choice which decreases our CO{sub 2} footprint is favored, even if it means a decrease in standard of living. The energy security constituency sees the geo-politics of oil becoming increasingly dire. They look at oil money being used to fund anti-American activities of groups such as the Wahabis in Saudi Arabia, Hezbollah in Lebanon and the infamous Al Qaeda. They quip that the Iraq war is the first war where we are paying for both sides. They note Iran and the Shia throughout the Middle East seeing the possibility of controlling

  13. Recognition and Reconstruction of Zebra Crossings on Roads from Mobile Laser Scanning Data

    Directory of Open Access Journals (Sweden)

    Lin Li

    2016-07-01

    Full Text Available Zebra crossings provide guidance and warning to pedestrians and drivers, thereby playing an important role in traffic safety management. Most previous studies have focused on detecting zebra stripes but have not provided full information about the areas, which is critical to both driver assistance systems and guide systems for blind individuals. This paper presents a stepwise procedure for recognizing and reconstructing zebra crossings using mobile laser scanning data. First, we propose adaptive thresholding based on road surface partitioning to reduce the impact of intensity unevenness and improve the accuracy of road marking extraction. Then, dispersion degree filtering is used to reduce the noise. Finally, zebra stripes are recognized according to the rectangular feature and fixed size, which is followed by area reconstruction according to arrangement patterns. We test our method on three datasets captured by an Optech Lynx mobile mapping system. The total recognition rate of 90.91% demonstrates the effectiveness of the method.

  14. A survey of urban reconstruction

    KAUST Repository

    Musialski, Przemyslaw

    2013-05-10

    This paper provides a comprehensive overview of urban reconstruction. While there exists a considerable body of literature, this topic is still under active research. The work reviewed in this survey stems from the following three research communities: computer graphics, computer vision and photogrammetry and remote sensing. Our goal is to provide a survey that will help researchers to better position their own work in the context of existing solutions, and to help newcomers and practitioners in computer graphics to quickly gain an overview of this vast field. Further, we would like to bring the mentioned research communities to even more interdisciplinary work, since the reconstruction problem itself is by far not solved. This paper provides a comprehensive overview of urban reconstruction. While there exists a considerable body of literature, this topic is still under active research. The work reviewed in this survey stems from the following three research communities: computer graphics, computer vision and photogrammetry and remote sensing. Our goal is to provide a survey that will help researchers to better position their own work in the context of existing solutions, and to help newcomers and practitioners in computer graphics to quickly gain an overview of this vast field. Further, we would like to bring the mentioned research communities to even more interdisciplinary work, since the reconstruction problem itself is by far not solved. © 2013 The Eurographics Association and John Wiley & Sons Ltd.

  15. Reconstructing Death in Postmodern Society.

    Science.gov (United States)

    Kastenbaum, Robert

    1993-01-01

    Examines interaction between emerging thanatological movement and its sociohistorical context. Notes that thanatology will take on new shape as individuals and society attempt to cope with postmodernistic forces and deconstructive mentality. Considers prospect for authentic solidarity against distress in reconstructed death system. (Author/NB)

  16. Rubber hands feel touch, but not in blind individuals.

    Science.gov (United States)

    Petkova, Valeria I; Zetterberg, Hedvig; Ehrsson, H Henrik

    2012-01-01

    Psychology and neuroscience have a long-standing tradition of studying blind individuals to investigate how visual experience shapes perception of the external world. Here, we study how blind people experience their own body by exposing them to a multisensory body illusion: the somatic rubber hand illusion. In this illusion, healthy blindfolded participants experience that they are touching their own right hand with their left index finger, when in fact they are touching a rubber hand with their left index finger while the experimenter touches their right hand in a synchronized manner (Ehrsson et al. 2005). We compared the strength of this illusion in a group of blind individuals (n = 10), all of whom had experienced severe visual impairment or complete blindness from birth, and a group of age-matched blindfolded sighted participants (n = 12). The illusion was quantified subjectively using questionnaires and behaviorally by asking participants to point to the felt location of the right hand. The results showed that the sighted participants experienced a strong illusion, whereas the blind participants experienced no illusion at all, a difference that was evident in both tests employed. A further experiment testing the participants' basic ability to localize the right hand in space without vision (proprioception) revealed no difference between the two groups. Taken together, these results suggest that blind individuals with impaired visual development have a more veridical percept of self-touch and a less flexible and dynamic representation of their own body in space compared to sighted individuals. We speculate that the multisensory brain systems that re-map somatosensory signals onto external reference frames are less developed in blind individuals and therefore do not allow efficient fusion of tactile and proprioceptive signals from the two upper limbs into a single illusory experience of self-touch as in sighted individuals.

  17. Prevalence and causes of low vision and blindness worldwide

    Directory of Open Access Journals (Sweden)

    A.O . Oduntan

    2005-01-01

    Full Text Available A recent review of the causes and prevalence of low vision and blindness world wide is lack-ing. Such review is important for highlighting the causes and prevalence of visual impairment in the different parts of the world. Also, it is important in providing information on the types and magnitude of eye care programs needed in different parts of the world. In this article, the causes and prevalence of low vision and blind-ness in different parts of the world are reviewed and  the  socio-economic  and  psychological implications are briefly discussed. The review is based on an extensive review of the litera-ture using computer data bases combined with review of available national, regional and inter-national journals. Low vision and blindness are more prevalent in the developing countries than in the developed ones. Generally, the causes and prevalence of the conditions vary widely in different parts of the world and even within the same country. World wide, cataract is the most common cause of blindness and low vision among adults and elderly. Infectious diseases such as trachoma and onchocerciasis result-ing in low vision and blindness are peculiar to Africa, Asia and South America. Hereditary and congenital conditions are the most common causes of low vision and blindness among chil-dren worldwide.

  18. Critical behavior of blind spots in sensor networks

    Science.gov (United States)

    Huang, Liang; Lai, Ying-Cheng; Park, Kwangho; Zhang, Junshan; Hu, Zhifeng

    2007-06-01

    Blind spots in sensor networks, i.e., individual nodes or small groups of nodes isolated from the rest of the network, are of great concern as they may significantly degrade the network's ability to collect and process information. As the operations of many types of sensors in realistic applications rely on short-lifetime power supplies (e.g., batteries), once they are used up ("off"), replacements become necessary ("on"). This off-and-on process can lead to blind spots. An issue of both theoretical and practical interest concerns the dynamical process and the critical behavior associated with the occurrence of blind spots. In particular, there can be various network topologies, and the off-and-on process can be characterized by the probability that a node functions normally, or the occupying probability of a node in the network. The question to be addressed in this paper concerns how the dynamics of blind spots depend on the network topology and on the occupying probability. For regular, random, and mixed networks, we provide theoretical formulas relating the probability of blind spots to the occupying probability, from which the critical point for the occurrence of blind spots can be determined. For scale-free networks, we present a procedure to estimate the critical point. While our theoretical and numerical analyses are presented in the framework of sensor networks, we expect our results to be generally applicable to network partitioning issues in other networks, such as the wireless cellular network, the Internet, or transportation networks, where the issue of blind spots may be of concern.

  19. Rubber hands feel touch, but not in blind individuals.

    Directory of Open Access Journals (Sweden)

    Valeria I Petkova

    Full Text Available Psychology and neuroscience have a long-standing tradition of studying blind individuals to investigate how visual experience shapes perception of the external world. Here, we study how blind people experience their own body by exposing them to a multisensory body illusion: the somatic rubber hand illusion. In this illusion, healthy blindfolded participants experience that they are touching their own right hand with their left index finger, when in fact they are touching a rubber hand with their left index finger while the experimenter touches their right hand in a synchronized manner (Ehrsson et al. 2005. We compared the strength of this illusion in a group of blind individuals (n = 10, all of whom had experienced severe visual impairment or complete blindness from birth, and a group of age-matched blindfolded sighted participants (n = 12. The illusion was quantified subjectively using questionnaires and behaviorally by asking participants to point to the felt location of the right hand. The results showed that the sighted participants experienced a strong illusion, whereas the blind participants experienced no illusion at all, a difference that was evident in both tests employed. A further experiment testing the participants' basic ability to localize the right hand in space without vision (proprioception revealed no difference between the two groups. Taken together, these results suggest that blind individuals with impaired visual development have a more veridical percept of self-touch and a less flexible and dynamic representation of their own body in space compared to sighted individuals. We speculate that the multisensory brain systems that re-map somatosensory signals onto external reference frames are less developed in blind individuals and therefore do not allow efficient fusion of tactile and proprioceptive signals from the two upper limbs into a single illusory experience of self-touch as in sighted individuals.

  20. Crossmodal Processing of Haptic Inputs in Sighted and Blind Individuals

    Science.gov (United States)

    Voss, Patrice; Alary, Flamine; Lazzouni, Latifa; Chapman, C. E.; Goldstein, Rachel; Bourgoin, Pierre; Lepore, Franco

    2016-01-01

    In a previous behavioral study, it was shown that early blind individuals were superior to sighted ones in discriminating two-dimensional (2D) tactile angle stimuli. The present study was designed to assess the neural substrate associated with a haptic 2D angle discrimination task in both sighted and blind individuals. Subjects performed tactile angle size discriminations in order to investigate whether the pattern of crossmodal occipital recruitment was lateralized as a function of the stimulated hand. Task-elicited activations were also compared across different difficulty levels to ascertain the potential modulatory role of task difficulty on crossmodal processing within occipital areas. We show that blind subjects had more widespread activation within the right lateral and superior occipital gyri when performing the haptic discrimination task. In contrast, the sighted activated the left cuneus and lingual gyrus more so than the blind when performing the task. Furthermore, activity within visual areas was shown to be predictive of tactile discrimination thresholds in the blind, but not in the sighted. Activity within parietal and occipital areas was modulated by task difficulty, where the easier angle comparison elicited more focal occipital activity along with bilateral posterior parietal activity, whereas the more difficult comparison produced more widespread occipital activity combined with reduced parietal activation. Finally, we show that crossmodal reorganization within the occipital cortex of blind individuals was primarily right lateralized, regardless of the stimulated hand, supporting previous evidence for a right-sided hemispheric specialization of the occipital cortex of blind individuals for the processing of tactile and haptic inputs. PMID:27531974

  1. A round robin exercise in archaeometry: analysis of a blind sample reproducing a seventeenth century pharmaceutical ointment.

    Science.gov (United States)

    Colombini, M P; Modugno, F; Gamberini, M C; Rocchi, M; Baraldi, C; Deviese, T; Stacey, R J; Orlandi, M; Saliu, F; Riedo, C; Chiantore, O; Sciutto, G; Catelli, E; Brambilla, L; Toniolo, L; Miliani, C; Rocchi, P; Bleton, J; Baumer, U; Dietemann, P; Pojana, G; Marras, S

    2011-10-01

    Chemical analysis of ancient residues of pharmaceutical or cosmetic preparations such as balms or ointments is made problematic by the high complexity of these mixtures, composed of organic and inorganic materials. Consequently, a multi-analytical approach and special caution in the interpretation of the results are necessary. In order to contribute to the improvement of analytical strategies for the characterization of complex residues and to reconstruct ancient medical practices, a replica of a pharmaceutical formulation of the seventeenth century was prepared in the laboratory according to a historically documented recipe. In a round robin exercise, a portion of the preparation was analysed as a blind sample by 11 laboratories using various analytical techniques. These included spectroscopic, chromatographic and mass spectrometric methods. None of the laboratories was able to completely reconstruct the complex formulation, but each of them gave partial positive results. The round robin exercise has demonstrated that the application of a multi-analytical approach can permit a complete and reliable reconstruction of the composition. Finally, on the basis of the results, an analytical protocol for the study of residues of ancient medical and pharmaceutical preparations has been outlined.

  2. Mandibular reconstruction in adults: a review.

    NARCIS (Netherlands)

    Goh, B.T.; Lee, S.; Tideman, H.; Stoelinga, P.J.W.

    2008-01-01

    Mandibular defects may result from trauma, inflammatory disease and benign or malignant tumours. Mastication, speech and facial aesthetics are often severely compromised without reconstruction. The goal of mandibular reconstruction is to restore facial form and function, implying repair of mandibula

  3. 3D Reconstruction Technique for Tomographic PIV

    Institute of Scientific and Technical Information of China (English)

    姜楠; 包全; 杨绍琼

    2015-01-01

    Tomographic particle image velocimetry(Tomo-PIV) is a state-of-the-art experimental technique based on a method of optical tomography to achieve the three-dimensional(3D) reconstruction for three-dimensional three-component(3D-3C) flow velocity measurements. 3D reconstruction for Tomo-PIV is carried out herein. Meanwhile, a 3D simplified tomographic reconstruction model reduced from a 3D volume light inten-sity field with 2D projection images into a 2D Tomo-slice plane with 1D projecting lines, i.e., simplifying this 3D reconstruction into a problem of 2D Tomo-slice plane reconstruction, is applied thereafter. Two kinds of the most well-known algebraic reconstruction techniques, algebraic reconstruction technique(ART) and multiple algebraic reconstruction technique(MART), are compared as well. The principles of the two reconstruction algorithms are discussed in detail, which has been performed by a series of simulation images, yielding the corresponding recon-struction images that show different features between the ART and MART algorithm, and then their advantages and disadvantages are discussed. Further discussions are made for the standard particle image reconstruction when the background noise of the pre-initial particle image has been removed. Results show that the particle image recon-struction has been greatly improved. The MART algorithm is much better than the ART. Furthermore, the computa-tional analyses of two parameters(the particle density and the number of cameras), are performed to study their effects on the reconstruction. Lastly, the 3D volume particle field is reconstructed by using the improved algorithm based on the simplified 3D tomographic reconstruction model, which proves that the algorithm simplification is feasible and it can be applied to the reconstruction of 3D volume particle field in a Tomo-PIV system.

  4. Top reconstruction and boosted top experimental overview

    CERN Document Server

    Skinnari, Louise

    2015-01-01

    An overview of techniques used to reconstruct resolved and boosted top quarks is presented. Techniques for resolved top quark reconstruction include kinematic likelihood fitters and pseudo- top reconstruction. Many tools and methods are available for the reconstruction of boosted top quarks, such as jet grooming techniques, jet substructure variables, and dedicated top taggers. Different techniques as used by ATLAS and CMS analyses are described and the performance of different variables and top taggers are shown.

  5. Thermographic image reconstruction using ultrasound reconstruction from virtual waves

    CERN Document Server

    Burgholzer, Peter; Gruber, Jürgen; Mayr, Günther

    2016-01-01

    Reconstruction of subsurface features from ultrasound signals measured on the surface is widely used in medicine and non-destructive testing. In this work, we introduce a concept how to use image reconstruction methods known from ultrasonic imaging for thermographic signals, i.e. on the measured temperature evolution on a sample surface. Before using these imaging methods a virtual signal is calculated by applying a transformation to the measured temperature evolution. The virtual signal is calculated locally for every detection point and has the same initial temperature distribution as the measured signal, but is a solution of the wave equation. The introduced transformation can be used for every shape of the detection surface and in every dimension. It describes all the irreversibility of the heat diffusion, which is responsible that the spatial resolution gets worse with increasing depth. Up to now, for thermographic imaging mostly one-dimensional methods, e.g., for depth-profiling were used, which are sui...

  6. A Modern Image Quality Measurement Method for Blind Image Restoration%基于变分的盲图像复原质量评价指标

    Institute of Scientific and Technical Information of China (English)

    成孝刚; 安明伟; 阮雅端; 陈启美

    2013-01-01

    盲图像复原过程中,图像质量评价至关重要.通过分析重构图像质量与其总变分值之间的关系,提出了用于图像复原的一种基于总变分(Total bounded variation,TBV)的图像质量评估方法,并构建关系模型,证明了原始清晰图像的总变分值在所有模糊图像中具有极大值,且在所有重构图像的变分值中具有极小值.通过分析,得出结论:当总变分取极值时,基于所提度量方法,可以获得更好的盲图像重构效果.最后,比较了原始清晰图像、模糊图像和重构图像之间的变分值,计算机仿真验证了该方法的有效性和准确性.%In the process of blind image restoration, image quality assessment is of paramount importance. In this paper, A novel image quality assessment method is presented by analyzing the relation between reconstructed image quality and its total bounded variation (TBV), on this basis, the relationship model is constructed, that is, the original clear image's TBV is maximum in all the blurring image, and it is minimal in all the reconstructed image. Further, based on the metric method proposed, the better blind image reconstruction effect is obtained when the TBV is extremal. Finally, the TBV of original clear image, blurred images and blind restored images are compared, the simulation results shows the validation and veracity of the method proposed.

  7. Vertex Reconstruction in ATLAS Run II

    CERN Document Server

    Zhang, Matt; The ATLAS collaboration

    2016-01-01

    Vertex reconstruction is the process of taking reconstructed tracks and using them to determine the locations of proton collisions. In this poster we present the performance of our current vertex reconstruction algorithm, and look at investigations into potential improvements from a new seed finding method.

  8. 盲者亦美丽%Blind Is Beautiful

    Institute of Scientific and Technical Information of China (English)

    翟厚全(译注)

    2012-01-01

    Do you know anyone who is Blind or Visually Impaired1? I do! ME! Hi, my name is Ashley. I am 15 years oldand I am visually impaired. I have a disorder called "Optic Nerve Hypoplasia". I attend a School for the Blind, so most of my friends are blind or visually impaired. People think a lot of different things about us Blind people. There are so many misconceptions3. I would like to clear a few of these up and hopefully help you to see that blind people are the same as the sighted.%虽然我们看不见,但是我们一样心思敏捷,一样自食其力。因此,请平等对待我们吧!你认识失明或视力有障碍的人吗?我认识!我就是?你好,我的名字叫阿什莉,我现年15岁,有视力障碍,我患上了一种名为“视神经发育不全”的眼疾,

  9. Blinding trachoma among refugees:complicating social disaster

    Institute of Scientific and Technical Information of China (English)

    Yeshigeta; Gelaw; Aemero; Abateneh

    2015-01-01

    Objective:To determine the prevalence of blinding trachoma among refugees in South Western Ethiopia.Methods:A cross-sectional outreach clinic based descriptive study was conducted on 1054 refugees in Southwest Ethiopia.A basic eyelid and cornea examination for signs of trachoma was done by using 2.5× binocular magnifying loupe.The findings were classified by using the World Health Digitization simplified trachoma grading system and data were analyzed by using SPSS version 16.0.Results:A total of 1054 refugee patients were examined for trachoma.179(16.98%) of them had clinical signs of trachoma.About 6(3.35%) patients had active trachoma with trachomatous trichiasis(TT),47(26.26%) patients had TT only and the rest 126(70.39%)patients had TT with trachomatous corneal opacity.All of the trachoma patients had blinding trachoma(TT with or without trachomatous corneal opacity),and about 60.89% of them had visual impairment.Blinding trachoma was significantly more common among females.patients in age group of 16-59 years,married patients,illiterates and Fugnido camp settlers(P<0.05).Conclusions:There is a very high burden of blinding trachoma among refugees.Urgent surgical intervention is needed to prevent blindness and low vision in the study subjects,and targeted regular outreach-based eye care service should be commenced.

  10. The global problem of blindness and visual dysfunction

    Science.gov (United States)

    Lakshminarayanan, Vasudevan

    2012-10-01

    According to World Health Organization statistics there are approximately 285 million people who are blind, have severe low vision, or are near-blind. Of these, 39 million are blind, and 246 million have low vision problems. About 90% of these live in developing countries. The major causes are uncorrected refractive errors (42%), and cataracts (38%). In the US, there are about 6 million people over the age of 65 who have age-related macular degeneration which is the leading cause of blindness. For each decade after age 40, it is found that there is a three-fold increase in the prevalence of blindness and low vision. This paper will address the question of what can we, as optical physicists and engineers, do? There is a need for efficient methods to detect problems, investigate function, provide solutions, and develop rehabilitation devices for the visually impaired. Here I will sketch out the magnitude and variety of the problem, examples and future research directions.

  11. TOOLS TO INCLUDE BLIND STUDENTS IN SCHOOL BUILDING PERFORMANCE ASSESSMENTS

    Directory of Open Access Journals (Sweden)

    Tania Pietzschke Abate

    2016-05-01

    Full Text Available This article discusses the design of data collection instruments that include the opinions of blind students, in accordance with the principles of Universal Design (UD. The aim of this study is to understand the importance of adapting data collection instruments for the inclusion of disabled persons in field research in Architecture and Design, among other fields. The data collection instruments developed were a play interview with a tactile map and a 3D survey with the use of tactile models. These instruments sought to assess the school environment experienced by blind students. The study involved students from the early years of a school for the blind who had not yet mastered the Braille system. The participation of these students was evaluated. A multidisciplinary team consisting of architects, designers, educators, and psychologists lent support to the study. The results showed that the data collection instruments adapted to blind students were successful in making the group of authors examine questions regarding UD. An analysis of the participatory phase showed that the limitations resulting from blindness determine the specificities in the adaptation and implementation process of the instruments in schools. Practical recommendations for future studies related to instruments in the UD thematic are presented. This approach is in line with the global trend of including disabled persons in society based on these users’ opinions concerning what was designed by architects and designers.

  12. Schizophrenia and cortical blindness: Protective effects and implications for language

    Directory of Open Access Journals (Sweden)

    Evelina eLeivada

    2014-11-01

    Full Text Available The repeatedly noted absence of case-reports of individuals with schizophrenia and congenital/early developed blindness has led several authors to argue that the latter can confer protective effects against the former. In this work, we present a number of relevant case-reports from different syndromes that show comorbidity of congenital and early blindness with schizophrenia. On the basis of these reports, we argue that a distinction between different types of blindness in terms of the origin of the visual deficit, cortical or peripheral, is crucial for understanding the observed patterns of comorbidity. We discuss the genetic underpinnings and the brain structures involved in schizophrenia and blindness, with insights from language processing, laying emphasis on the three structures that particularly stand out: the occipital cortex, the lateral geniculate nucleus and the pulvinar. Last, we build on previous literature on the nature of the protective effects in order to offer novel insights into the nature of the protection mechanism from the perspective of the brain structures involved in each type of blindness.

  13. Schizophrenia and cortical blindness: protective effects and implications for language.

    Science.gov (United States)

    Leivada, Evelina; Boeckx, Cedric

    2014-01-01

    The repeatedly noted absence of case-reports of individuals with schizophrenia and congenital/early developed blindness has led several authors to argue that the latter can confer protective effects against the former. In this work, we present a number of relevant case-reports from different syndromes that show comorbidity of congenital and early blindness with schizophrenia. On the basis of these reports, we argue that a distinction between different types of blindness in terms of the origin of the visual deficit, cortical or peripheral, is crucial for understanding the observed patterns of comorbidity. We discuss the genetic underpinnings and the brain structures involved in schizophrenia and blindness, with insights from language processing, laying emphasis on the three structures that particularly stand out: the occipital cortex, the lateral geniculate nucleus (LGN), and the pulvinar. Last, we build on previous literature on the nature of the protective effects in order to offer novel insights into the nature of the protection mechanism from the perspective of the brain structures involved in each type of blindness.

  14. Preferential interactions promote blind cooperation and informed defection.

    Science.gov (United States)

    Pérez-Escudero, Alfonso; Friedman, Jonathan; Gore, Jeff

    2016-12-06

    It is common sense that costs and benefits should be carefully weighed before deciding on a course of action. However, we often disapprove of people who do so, even when their actual decision benefits us. For example, we prefer people who directly agree to do us a favor over those who agree only after securing enough information to ensure that the favor will not be too costly. Why should we care about how people make their decisions, rather than just focus on the decisions themselves? Current models show that punishment of information gathering can be beneficial because it forces blind decisions, which under some circumstances enhances cooperation. Here we show that aversion to information gathering can be beneficial even in the absence of punishment, due to a different mechanism: preferential interactions with reliable partners. In a diverse population where different people have different-and unknown-preferences, those who seek additional information before agreeing to cooperate reveal that their preferences are close to the point where they would choose not to cooperate. Blind cooperators are therefore more likely to keep cooperating even if conditions change, and aversion to information gathering helps to interact preferentially with them. Conversely, blind defectors are more likely to keep defecting in the future, leading to a preference for informed defectors over blind ones. Both mechanisms-punishment to force blind decisions and preferential interactions-give qualitatively different predictions, which may enable experimental tests to disentangle them in real-world situations.

  15. Optimal image reconstruction intervals for non-invasive coronary angiography with 64-slice CT

    Energy Technology Data Exchange (ETDEWEB)

    Leschka, Sebastian; Husmann, Lars; Desbiolles, Lotus M.; Boehm, Thomas; Marincek, Borut; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Gaemperli, Oliver; Schepis, Tiziano; Koepfli, Pascal [University Hospital Zurich, Cardiovascular Center, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiovascular Center, Zurich (Switzerland); University of Zurich, Center for Integrative Human Physiology, Zurich (Switzerland)

    2006-09-15

    The reconstruction intervals providing best image quality for non-invasive coronary angiography with 64-slice computed tomography (CT) were evaluated. Contrast-enhanced, retrospectively electrocardiography (ECG)-gated 64-slice CT coronary angiography was performed in 80 patients (47 male, 33 female; mean age 62.1{+-}10.6 years). Thirteen data sets were reconstructed in 5% increments from 20 to 80% of the R-R interval. Depending on the average heart rate during scanning, patients were grouped as <65 bpm (n=49) and {>=}65 bpm (n=31). Two blinded and independent readers assessed the image quality of each coronary segment with a diameter {>=}1.5 mm using the following scores: 1, no motion artifacts; 2, minor artifacts; 3, moderate artifacts; 4, severe artifacts; and 5, not evaluative. The average heart rate was 63.3{+-}13.1 bpm (range 38-102). Acceptable image quality (scores 1-3) was achieved in 99.1% of all coronary segments (1,162/1,172; mean image quality score 1.55{+-}0.77) in the best reconstruction interval. Best image quality was found at 60% and 65% of the R-R interval for all patients and for each heart rate subgroup, whereas motion artifacts occurred significantly more often (P<0.01) at other reconstruction intervals. At heart rates <65 bpm, acceptable image quality was found in all coronary segments at 60%. At heart rates {>=}65 bpm, the whole coronary artery tree could be visualized with acceptable image quality in 87% (27/31) of the patients at 60%, while ten segments in four patients were rated as non-diagnostic (scores 4-5) at any reconstruction interval. In conclusion, 64-slice CT coronary angiography provides best overall image quality in mid-diastole. At heart rates <65 bpm, diagnostic image quality of all coronary segments can be obtained at a single reconstruction interval of 60%. (orig.)

  16. Model Based Iterative Reconstruction for Bright Field Electron Tomography (Postprint)

    Science.gov (United States)

    2013-02-01

    Reconstruction Technique ( SIRT ) are applied to the data. Model based iterative reconstruction (MBIR) provides a powerful framework for tomographic...the reconstruction when the typical algorithms such as Filtered Back Projection (FBP) and Simultaneous Iterative Reconstruction Technique ( SIRT ) are

  17. Network reconstruction via density sampling

    CERN Document Server

    Squartini, Tiziano; Gabrielli, Andrea; Garlaschelli, Diego

    2016-01-01

    Reconstructing weighted networks from partial information is necessary in many important circumstances, e.g. for a correct estimation of systemic risk. It has been shown that, in order to achieve an accurate reconstruction, it is crucial to reliably replicate the empirical degree sequence, which is however unknown in many realistic situations. More recently, it has been found that the knowledge of the degree sequence can be replaced by the knowledge of the strength sequence, which is typically accessible, complemented by that of the total number of links, thus considerably relaxing the observational requirements. Here we further relax these requirements and devise a procedure valid when even the the total number of links is unavailable. We assume that, apart from the heterogeneity induced by the degree sequence itself, the network is homogeneous, so that its link density can be estimated by sampling subsets of nodes with representative density. We show that the best way of sampling nodes is the random selecti...

  18. Bayes reconstruction of missing teeth

    DEFF Research Database (Denmark)

    Sporring, Jon; Jensen, Katrine Hommelhoff

    2008-01-01

     We propose a method for restoring the surface of tooth crowns in a 3D model of a human denture, so that the pose and anatomical features of the tooth will work well for chewing. This is achieved by including information about the position and anatomy of the other teeth in the mouth. Our system...... contains two major parts: A statistical model of a selection of tooth shapes and a reconstruction of missing data. We use a training set consisting of 3D scans of dental cast models obtained with a laser scanner, and we have build a model of the shape variability of the teeth, their neighbors...... regularization of the log-likelihood estimate based on differential geometrical properties of teeth surfaces, and we show general conditions under which this may be considered a Bayes prior.Finally we use Bayes method to propose the reconstruction of missing data, for e.g. finding the most probable shape...

  19. Reconstruction of complete interval tournaments

    CERN Document Server

    Iványi, Antal

    2010-01-01

    Let $a, b$ and $n$ be nonnegative integers $(b \\geq a, \\ b > 0, \\ n \\geq 1)$, $\\mathcal{G}_n(a,b)$ be a multigraph on $n$ vertices in which any pair of vertices is connected with at least $a$ and at most $b$ edges and \\textbf{v =} $(v_1, v_2, ..., v_n)$ be a vector containing $n$ nonnegative integers. We give a necessary and sufficient condition for the existence of such orientation of the edges of $\\mathcal{G}_n(a,b)$, that the resulted out-degree vector equals to \\textbf{v}. We describe a reconstruction algorithm. In worst case checking of \\textbf{v} requires $\\Theta(n)$ time and the reconstruction algorithm works in $O(bn^3)$ time. Theorems of H. G. Landau (1953) and J. W. Moon (1963) on the score sequences of tournaments are special cases $b = a = 1$ resp. $b = a \\geq 1$ of our result.

  20. X-Ray Tomographic Reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Bonnie Schmittberger

    2010-08-25

    Tomographic scans have revolutionized imaging techniques used in medical and biological research by resolving individual sample slices instead of several superimposed images that are obtained from regular x-ray scans. X-Ray fluorescence computed tomography, a more specific tomography technique, bombards the sample with synchrotron x-rays and detects the fluorescent photons emitted from the sample. However, since x-rays are attenuated as they pass through the sample, tomographic scans often produce images with erroneous low densities in areas where the x-rays have already passed through most of the sample. To correct for this and correctly reconstruct the data in order to obtain the most accurate images, a program employing iterative methods based on the inverse Radon transform was written. Applying this reconstruction method to a tomographic image recovered some of the lost densities, providing a more accurate image from which element concentrations and internal structure can be determined.