WorldWideScience

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. A Regularization Approach to Blind Deblurring and Denoising of QR Barcodes

    OpenAIRE

    van Gennip, Yves; Athavale, Prashant; Gilles, Jérôme; Choksi, Rustum

    2014-01-01

    QR bar codes are prototypical images for which part of the image is a priori known (required patterns). Open source bar code readers, such as ZBar, are readily available. We exploit both these facts to provide and assess purely regularization-based methods for blind deblurring of QR bar codes in the presence of noise.

  3. A Regularization Approach to Blind Deblurring and Denoising of QR Barcodes.

    Science.gov (United States)

    van Gennip, Yves; Athavale, Prashant; Gilles, Jérôme; Choksi, Rustum

    2015-09-01

    QR bar codes are prototypical images for which part of the image is a priori known (required patterns). Open source bar code readers, such as ZBar, are readily available. We exploit both these facts to provide and assess purely regularization-based methods for blind deblurring of QR bar codes in the presence of noise. PMID:25974935

  4. 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.

  5. Blind Deblurring and Denoising of Images Corrupted by Unidirectional Object Motion Blur and Sensor Noise.

    Science.gov (United States)

    Zhang, Yi; Hirakawa, Keigo

    2016-09-01

    Low light photography suffers from blur and noise. In this paper, we propose a novel method to recover a dense estimate of spatially varying blur kernel as well as a denoised and deblurred image from a single noisy and object motion blurred image. A proposed method takes the advantage of the sparse representation of double discrete wavelet transform-a generative model of image blur that simplifies the wavelet analysis of a blurred image-and the Bayesian perspective of modeling the prior distribution of the latent sharp wavelet coefficient and the likelihood function that makes the noise handling explicit. We demonstrate the effectiveness of the proposed method on moderate noise and severely blurred images using simulated and real camera data. PMID:27337717

  6. Blind image deblurring based on trained dictionary and curvelet using sparse representation

    Science.gov (United States)

    Feng, Liang; Huang, Qian; Xu, Tingfa; Li, Shao

    2015-04-01

    Motion blur is one of the most significant and common artifacts causing poor image quality in digital photography, in which many factors resulted. In imaging process, if the objects are moving quickly in the scene or the camera moves in the exposure interval, the image of the scene would blur along the direction of relative motion between the camera and the scene, e.g. camera shake, atmospheric turbulence. Recently, sparse representation model has been widely used in signal and image processing, which is an effective method to describe the natural images. In this article, a new deblurring approach based on sparse representation is proposed. An overcomplete dictionary learned from the trained image samples via the KSVD algorithm is designed to represent the latent image. The motion-blur kernel can be treated as a piece-wise smooth function in image domain, whose support is approximately a thin smooth curve, so we employed curvelet to represent the blur kernel. Both of overcomplete dictionary and curvelet system have high sparsity, which improves the robustness to the noise and more satisfies the observer's visual demand. With the two priors, we constructed restoration model of blurred images and succeeded to solve the optimization problem with the help of alternating minimization technique. The experiment results prove the method can preserve the texture of original images and suppress the ring artifacts effectively.

  7. 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.

  8. 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.

  9. Regularization mechanism in blind tip reconstruction procedure

    International Nuclear Information System (INIS)

    In quantitative investigations of mechanical and chemical surface parameters using atomic force microscopy (AFM) techniques the determination of the probe radius and shape is required. To the most favorable methods of the microprobe characterization belongs the blind tip reconstruction method (BTR). The BTR similar to many other inverse problems is sensitive to noise and needs the so-called regularization mechanism. In this article we describe and investigate two the most popular regularization schemes, which were proposed in Villarubia et al. (1997) and Tian et al. (2008) . We have shown that the procedure described in Tian et al. (2008) enables very effective probe shape reconstruction if we know the statistics of noise present in the AFM system. The increase of effectiveness with relation to the procedure described in Villarubia (1997) is so significant that makes it possible to reconstruct probes with much larger resolution. We have also noticed the fact, that probes reconstructed by means of the procedure presented in Tian et al. (2008) have flat apexes for AFM images with low signal to noise ratio (SNR). We propose procedure, which can improve the probe apex reconstruction. It uses the AFM image to estimate the initial shape of the reconstructed probe. This shape may be further improved by the BTR algorithm. We have shown that it is possible only for the procedure described in Tian et al. (2008) . -- Highlights: ► We study regularization mechanism of blind tip reconstruction. ► We propose combination of direct probe imaging with BTR to improve the reconstruction of a probe apex. ► The possibility of improving efficiency of the BTR procedure is presented. ► The possibility of improving resolution of a reconstructed probe is presented.

  10. 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 algo- rithms 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.

  11. Dictionary Learning for Deblurring and Digital Zoom

    CERN Document Server

    Couzinie-Devy, Florent; Bach, Francis; Ponce, Jean

    2011-01-01

    This paper proposes a novel approach to image deblurring and digital zooming using sparse local models of image appearance. These models, where small image patches are represented as linear combinations of a few elements drawn from some large set (dictionary) of candidates, have proven well adapted to several image restoration tasks. A key to their success has been to learn dictionaries adapted to the reconstruction of small image patches. In contrast, recent works have proposed instead to learn dictionaries which are not only adapted to data reconstruction, but also tuned for a specific task. We introduce here such an approach to deblurring and digital zoom, using pairs of blurry/sharp (or low-/high-resolution) images for training, as well as an effective stochastic gradient algorithm for solving the corresponding optimization task. Although this learning problem is not convex, once the dictionaries have been learned, the sharp/high-resolution image can be recovered via convex optimization at test time. Expe...

  12. A new double views motion deblurring method

    Science.gov (United States)

    Hong, Hanyu; Hua, Xia; Zhang, Wenmo; Shi, Yu

    2015-12-01

    With improving of intelligent and automation in modern industrial production area, the detection and reconstruction of the 3D surface of the product has become an important technology, but the image which acquire on the actual production line has motion blur and this problem will affect the later reconstruction work. In order to solve this problem, a deblurring method which based on double view moving target image is proposed in this paper. We can deduce the relationship of the point spread function(PSF) path between the double view image through the epipolar geometry and the camera model. The experimental results show that deblurring with the PSF path solved by the geometric relationship achieves good results.

  13. Image Deblurring with Krylov Subspace Methods

    DEFF Research Database (Denmark)

    Hansen, Per Christian

    2011-01-01

    Image deblurring, i.e., reconstruction of a sharper image from a blurred and noisy one, involves the solution of a large and very ill-conditioned system of linear equations, and regularization is needed in order to compute a stable solution. Krylov subspace methods are often ideally suited...... the three Krylov subspace methods CGLS, MINRES, and GMRES. We describe their regularizing properties, and we discuss some computational aspects such as preconditioning and stopping criteria....

  14. Dictionary Learning for Deblurring and Digital Zoom

    OpenAIRE

    Couzinie-Devy, Florent; Mairal, Julien; Bach, Francis; Ponce, Jean

    2011-01-01

    International audience This paper proposes a novel approach to image deblurring and digital zooming using sparse local models of image appearance. These models, where small image patches are represented as linear combinations of a few elements drawn from some large set (dictionary) of candidates, have proven well adapted to several image restoration tasks. A key to their success has been to learn dictionaries adapted to the reconstruction of small image patches. In contrast, recent works h...

  15. 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.

  16. Fluorescence blind structured illumination microscopy: a new reconstruction strategy

    OpenAIRE

    Labouesse, S.; Allain, Marc; Idier, J.; Bourguignon, S.; Negash, A.; Liu, P.; Sentenac, A.

    2016-01-01

    International audience In this communication, a fast reconstruction algorithm is proposed for fluorescence blind structured illumination mi-croscopy (SIM) under the sample positivity constraint. This new algorithm is by far simpler and faster than existing solutions , paving the way to 3D and real-time 2D reconstruction.

  17. Antireflective Boundary Conditions for Deblurring Problems

    Directory of Open Access Journals (Sweden)

    Marco Donatelli

    2010-01-01

    Full Text Available This survey paper deals with the use of antireflective boundary conditions for deblurring problems where the issues that we consider are the precision of the reconstruction when the noise is not present, the linear algebra related to these boundary conditions, the iterative and noniterative regularization solvers when the noise is considered, both from the viewpoint of the computational cost and from the viewpoint of the quality of the reconstruction. In the latter case, we consider a reblurring approach that replaces the transposition operation with correlation. For many of the considered items, the anti-reflective algebra coming from the given boundary conditions is the optimal choice. Numerical experiments corroborating the previous statement and a conclusion section end the paper.

  18. Learning to Deblur.

    Science.gov (United States)

    Schuler, Christian J; Hirsch, Michael; Harmeling, Stefan; Scholkopf, Bernhard

    2016-07-01

    We describe a learning-based approach to blind image deconvolution. It uses a deep layered architecture, parts of which are borrowed from recent work on neural network learning, and parts of which incorporate computations that are specific to image deconvolution. The system is trained end-to-end on a set of artificially generated training examples, enabling competitive performance in blind deconvolution, both with respect to quality and runtime. PMID:26415157

  19. 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.

  20. Image deblurring with Poisson data: from cells to galaxies

    International Nuclear Information System (INIS)

    Image deblurring is an important topic in imaging science. In this review, we consider together fluorescence microscopy and optical/infrared astronomy because of two common features: in both cases the imaging system can be described, with a sufficiently good approximation, by a convolution operator, whose kernel is the so-called point-spread function (PSF); moreover, the data are affected by photon noise, described by a Poisson process. This statistical property of the noise, that is common also to emission tomography, is the basis of maximum likelihood and Bayesian approaches introduced in the mid eighties. From then on, a huge amount of literature has been produced on these topics. This review is a tutorial and a review of a relevant part of this literature, including some of our previous contributions. We discuss the mathematical modeling of the process of image formation and detection, and we introduce the so-called Bayesian paradigm that provides the basis of the statistical treatment of the problem. Next, we describe and discuss the most frequently used algorithms as well as other approaches based on a different description of the Poisson noise. We conclude with a review of other topics related to image deblurring such as boundary effect correction, space-variant PSFs, super-resolution, blind deconvolution and multiple-image deconvolution. (topical review)

  1. 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...

  2. 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.

  3. Blindness

    Science.gov (United States)

    ... Got Homework? Here's Help White House Lunch Recipes Blindness KidsHealth > For Kids > Blindness Print A A A ... help, are sometimes called "legally blind." What Causes Blindness? Vision problems can develop before a baby is ...

  4. 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 ...

  5. Enhancement of the migrated results with the deblurring filter

    Science.gov (United States)

    Yi, Li; Takahashi, Kazunori; Sato, Motoyuki

    2016-04-01

    In this paper we introduce a method that uses the deblurring filter to further improve the migrated GPR results. While applying migration to near range radar systems such as GPR, we may suffer from the imaging artifacts or low resolution due to the limited aperture size or coarsely sampled data. In order to solve this problem, least square approach can be applied. It can be presented with the following equations: The forward modelling can be presented as a linear calculation as (1) d = Lm (1) The real inverse processing should be (2) m = L‑1d (2) Here d is the acquired GPR data, L is the forward modelling matrix and m is the reflectivity model of the survey area. Since the inverse matrix L‑1 PIC is almost impossible to determine, we normally use the simplified method that use the adjoint matrix as the estimation of the inverse matrix. And it is proved that migration is just the adjoint matrix of the forward modelling matrix. Hence the migration processing can be written as (3) m* = LTd (3) The analytic least square solution can be given as (4) m* = (LTL + μI)‑1 LTd (4) The least square results give much higher resolution and most of the artifacts can be eliminated. But this method requires extremely large computation so it is not really practical. Here we propose another approach, by combining (1) and (3) we can also get (5) m = (LTL)‑1 m* (5) It indicates that we may further improve the migrated results with an inverse filter (LTL)‑1. Actually, this is known as the deblurring processing for imaging problem. This deblurring filter is still very difficult to solve for the whole imaging area, but we can use the local filters at different position instead of a whole filter. In order to realize this method, a dictionary needs to be reconstructed correspond to the antenna configuration and the background velocity first. At each local window we put a point scatter in the middle and calculate the forward modelling result and the migrated result of this local

  6. 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...

  7. Image reconstruction from phased-array data based on multichannel blind deconvolution.

    Science.gov (United States)

    She, Huajun; Chen, Rong-Rong; Liang, Dong; Chang, Yuchou; Ying, Leslie

    2015-11-01

    In this paper we consider image reconstruction from fully sampled multichannel phased array MRI data without knowledge of the coil sensitivities. To overcome the non-uniformity of the conventional sum-of-square reconstruction, a new framework based on multichannel blind deconvolution (MBD) is developed for joint estimation of the image function and the sensitivity functions in image domain. The proposed approach addresses the non-uniqueness of the MBD problem by exploiting the smoothness of both functions in the image domain through regularization. Results using simulation, phantom and in vivo experiments demonstrate that the reconstructions by the proposed algorithm are more uniform than those by the existing methods. PMID:26119418

  8. 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.

  9. 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.

  10. 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).

  11. 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.

  12. MO-G-17A-05: PET Image Deblurring Using Adaptive Dictionary Learning

    International Nuclear Information System (INIS)

    Purpose: The aim of this work is to deblur PET images while suppressing Poisson noise effects using adaptive dictionary learning (DL) techniques. Methods: The model that relates a blurred and noisy PET image to the desired image is described as a linear transform y=Hm+n where m is the desired image, H is a blur kernel, n is Poisson noise and y is the blurred image. The approach we follow to recover m involves the sparse representation of y over a learned dictionary, since the image has lots of repeated patterns, edges, textures and smooth regions. The recovery is based on an optimization of a cost function having four major terms: adaptive dictionary learning term, sparsity term, regularization term, and MLEM Poisson noise estimation term. The optimization is solved by a variable splitting method that introduces additional variables. We simulated a 128×128 Hoffman brain PET image (baseline) with varying kernel types and sizes (Gaussian 9×9, σ=5.4mm; Uniform 5×5, σ=2.9mm) with additive Poisson noise (Blurred). Image recovery was performed once when the kernel type was included in the model optimization and once with the model blinded to kernel type. The recovered image was compared to the baseline as well as another recovery algorithm PIDSPLIT+ (Setzer et. al.) by calculating PSNR (Peak SNR) and normalized average differences in pixel intensities (NADPI) of line profiles across the images. Results: For known kernel types, the PSNR of the Gaussian (Uniform) was 28.73 (25.1) and 25.18 (23.4) for DL and PIDSPLIT+ respectively. For blinded deblurring the PSNRs were 25.32 and 22.86 for DL and PIDSPLIT+ respectively. NADPI between baseline and DL, and baseline and blurred for the Gaussian kernel was 2.5 and 10.8 respectively. Conclusion: PET image deblurring using dictionary learning seems to be a good approach to restore image resolution in presence of Poisson noise. GE Health Care

  13. MO-G-17A-05: PET Image Deblurring Using Adaptive Dictionary Learning

    Energy Technology Data Exchange (ETDEWEB)

    Valiollahzadeh, S [RICE University, Houston, Tx (United States); Clark, J [MD Anderson Cancer Ctr., Houston, TX (United States); Mawlawi, O

    2014-06-15

    Purpose: The aim of this work is to deblur PET images while suppressing Poisson noise effects using adaptive dictionary learning (DL) techniques. Methods: The model that relates a blurred and noisy PET image to the desired image is described as a linear transform y=Hm+n where m is the desired image, H is a blur kernel, n is Poisson noise and y is the blurred image. The approach we follow to recover m involves the sparse representation of y over a learned dictionary, since the image has lots of repeated patterns, edges, textures and smooth regions. The recovery is based on an optimization of a cost function having four major terms: adaptive dictionary learning term, sparsity term, regularization term, and MLEM Poisson noise estimation term. The optimization is solved by a variable splitting method that introduces additional variables. We simulated a 128×128 Hoffman brain PET image (baseline) with varying kernel types and sizes (Gaussian 9×9, σ=5.4mm; Uniform 5×5, σ=2.9mm) with additive Poisson noise (Blurred). Image recovery was performed once when the kernel type was included in the model optimization and once with the model blinded to kernel type. The recovered image was compared to the baseline as well as another recovery algorithm PIDSPLIT+ (Setzer et. al.) by calculating PSNR (Peak SNR) and normalized average differences in pixel intensities (NADPI) of line profiles across the images. Results: For known kernel types, the PSNR of the Gaussian (Uniform) was 28.73 (25.1) and 25.18 (23.4) for DL and PIDSPLIT+ respectively. For blinded deblurring the PSNRs were 25.32 and 22.86 for DL and PIDSPLIT+ respectively. NADPI between baseline and DL, and baseline and blurred for the Gaussian kernel was 2.5 and 10.8 respectively. Conclusion: PET image deblurring using dictionary learning seems to be a good approach to restore image resolution in presence of Poisson noise. GE Health Care.

  14. 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.

  15. Deghosting, Demultiple, and Deblurring in Controlled-Source Seismic Interferometry

    Directory of Open Access Journals (Sweden)

    Joost van der Neut

    2011-01-01

    Full Text Available With controlled-source seismic interferometry we aim to redatum sources to downhole receiver locations without requiring a velocity model. Interferometry is generally based on a source integral over cross-correlation (CC pairs of full, perturbed (time-gated, or decomposed wavefields. We provide an overview of ghosts, multiples, and spatial blurring effects that can occur for different types of interferometry. We show that replacing cross-correlation by multidimensional deconvolution (MDD can deghost, demultiple, and deblur retrieved data. We derive and analyze MDD for perturbed and decomposed wavefields. An interferometric point spread function (PSF is introduced that can be obtained directly from downhole data. Ghosts, multiples, and blurring effects that may populate the retrieved gathers can be locally diagnosed with the PSF. MDD of perturbed fields can remove ghosts and deblur retrieved data, but it leaves particular multiples in place. To remove all overburden-related effects, MDD of decomposed fields should be applied.

  16. An Adaptively Accelerated Bayesian Deblurring Method with Entropy Prior

    Directory of Open Access Journals (Sweden)

    Yong-Hoon Kim

    2008-05-01

    Full Text Available The development of an efficient adaptively accelerated iterative deblurring algorithm based on Bayesian statistical concept has been reported. Entropy of an image has been used as a “prior” distribution and instead of additive form, used in conventional acceleration methods an exponent form of relaxation constant has been used for acceleration. Thus the proposed method is called hereafter as adaptively accelerated maximum a posteriori with entropy prior (AAMAPE. Based on empirical observations in different experiments, the exponent is computed adaptively using first-order derivatives of the deblurred image from previous two iterations. This exponent improves speed of the AAMAPE method in early stages and ensures stability at later stages of iteration. In AAMAPE method, we also consider the constraint of the nonnegativity and flux conservation. The paper discusses the fundamental idea of the Bayesian image deblurring with the use of entropy as prior, and the analytical analysis of superresolution and the noise amplification characteristics of the proposed method. The experimental results show that the proposed AAMAPE method gives lower RMSE and higher SNR in 44% lesser iterations as compared to nonaccelerated maximum a posteriori with entropy prior (MAPE method. Moreover, AAMAPE followed by wavelet wiener filtering gives better result than the state-of-the-art methods.

  17. Application of digital tomosynthesis (DTS) of optimal deblurring filters for dental X-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Oh, J. E.; Cho, H. S.; Kim, D. S.; Choi, S. I.; Je, U. K. [Yonsei University, Wonju (Korea, Republic of)

    2012-04-15

    Digital tomosynthesis (DTS) is a limited-angle tomographic technique that provides some of the tomographic benefits of computed tomography (CT) but at reduced dose and cost. Thus, the potential for application of DTS to dental X-ray imaging seems promising. As a continuation of our dental radiography R and D, we developed an effective DTS reconstruction algorithm and implemented it in conjunction with a commercial dental CT system for potential use in dental implant placement. The reconstruction algorithm employed a backprojection filtering (BPF) method based upon optimal deblurring filters to suppress effectively both the blur artifacts originating from the out-focus planes and the high-frequency noise. To verify the usefulness of the reconstruction algorithm, we performed systematic simulation works and evaluated the image characteristics. We also performed experimental works in which DTS images of enhanced anatomical resolution were successfully obtained by using the algorithm and were promising to our ongoing applications to dental X-ray imaging. In this paper, our approach to the development of the DTS reconstruction algorithm and the results are described in detail.

  18. Application of digital tomosynthesis (DTS) of optimal deblurring filters for dental X-ray imaging

    Science.gov (United States)

    Oh, J. E.; Cho, H. S.; Kim, D. S.; Choi, S. I.; Je, U. K.

    2012-04-01

    Digital tomosynthesis (DTS) is a limited-angle tomographic technique that provides some of the tomographic benefits of computed tomography (CT) but at reduced dose and cost. Thus, the potential for application of DTS to dental X-ray imaging seems promising. As a continuation of our dental radiography R&D, we developed an effective DTS reconstruction algorithm and implemented it in conjunction with a commercial dental CT system for potential use in dental implant placement. The reconstruction algorithm employed a backprojection filtering (BPF) method based upon optimal deblurring filters to suppress effectively both the blur artifacts originating from the out-focus planes and the high-frequency noise. To verify the usefulness of the reconstruction algorithm, we performed systematic simulation works and evaluated the image characteristics. We also performed experimental works in which DTS images of enhanced anatomical resolution were successfully obtained by using the algorithm and were promising to our ongoing applications to dental X-ray imaging. In this paper, our approach to the development of the DTS reconstruction algorithm and the results are described in detail.

  19. 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.

  20. Application of Non-Iterative Method in Image Deblurring

    Directory of Open Access Journals (Sweden)

    MILADINOVIC Marko

    2012-05-01

    Full Text Available This paper presents a non-iterative method thatfinds application in a broad scientific field such as imagedeblurring. A method for image deblurring, based on thepseudo-inverse matrix is apply for removal of blurr inan image caused by linear motion. This methodassumes that linear motion corresponds to an integralnumber of pixels. Compared to other classicalmethods, this method attains higher values of theImprovement in Signal to Noise Ratio (ISNRparameter and of the Peak Signal-to-Noise Ratio(PSNR. We give an implementation in the MATLABprogramming package.

  1. 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.

  2. Can CT image deblurring improve finite element predictions at the proximal femur?

    Science.gov (United States)

    Falcinelli, Cristina; Schileo, Enrico; Pakdel, Amirreza; Whyne, Cari; Cristofolini, Luca; Taddei, Fulvia

    2016-10-01

    The aim of this study was to determine if a CT image deblurring algorithm can improve CT-based FE modelling accuracy at the proximal femur. Experimental data (CT scans of fourteen proximal fresh-frozen cadaveric femurs, non-destructive surface strain measurements in stance and sideways fall loading configurations on all femurs, and failure loads obtained in stance for seven specimens, in sideways fall for the other seven) were taken from a recent study (Schileo et al., 2014). An estimate of the 3D Point Spread Function for each CT scan was used within a deconvolution solver to perform the deblurring. The most proximal regions of three specimens were scanned using an HRpQCT scanner and compared to the original and deblurred CT images to quantify errors in bone contour estimates and determine correlation of intensity values within the bone contours. Subject-specific FE models of the proximal femur were generated. The accuracy of deblurred FE predictions against experimental measurements was compared to the published (non-deblurred) FE results. When compared to HRpQCT, CT deblurring led to lower mean surface distances (0.31 vs. 0.49mm) and higher CT intensity correlations with respect to the original CT. All indicators of strain prediction accuracy were significantly improved in deblurred FE models, more markedly at the femoral neck (peak error reduced by 38%). Failure load prediction, based on a simple elastic limit model, was also improved in deblurred FE models, although differently for stance and sideways fall loading conditions. In stance, correlation was unchanged, but specimen-wise errors were reduced (mean error 10% vs. 15%). In sideways fall, correlation notably increased (R(2)=0.95 vs. 0.81), despite a general overestimation of failure load. In summary, the proposed CT deblurring technique yielded moderate but significant improvements in FE predictions, and may thus be considered a first step toward the improvement of CT-based FE models of the human femur

  3. Real-time image acquisition and deblurring for underwater gravel extraction by smartphone

    Directory of Open Access Journals (Sweden)

    Ming-Fu Chen

    2014-02-01

    Full Text Available Gravel size distribution is an important aspect of stream investigation. Using water photography to determine such distribution is a simple and cost-effective approach for gathering instream gravel information. However, good-quality images of underwater gravels in shallow areas are difficult to acquire because of the flow- and wind-induced perturbation at water surface. Thus, two Lucy–Richardson iterations are applied on an averaged image to obtain a deblurred image for gravel extraction. A Matlab code for multi-frame image averaging and image deblurring is implemented on a laptop computer. Underwater gravel images are acquired using a video camera and processed offline. Thus, the usability of the images acquired during field investigation cannot be determined immediately. However, returning to the investigated streams for additional data gathering would be costly, and the cameras may accidentally be dropped into the water. This paper presents multi-frame image averaging and image deblurring smartphone-based approaches for underwater gravel extraction. A waterproof smartphone is used to acquire the images, on which image deblurring is immediately conducted to test whether the images can be used for gravel extraction. The averaged image of using mean-based filter is derived during real-time image acquisition. The deblurred image is derived block-by-block because of limited memory capacity of smartphones. The time consumed for acquiring 1500 frame images with size of 1280 × 720 pixels is approximately 6 min by Sony Xperia smartphones. Image averaging can be performed in real time during image acquisition. Image deblurring is accomplished accurately and is consistent with results of the Matlab code. The processing time for image deblurring is approximately 12 min. A compact system for underwater gravel investigation using smartphones is successfully developed in this study. Image acquisition and deblurring are completed in real time at the

  4. Deblurring molecular images using desorption electrospray ionization mass spectrometry

    Science.gov (United States)

    Parry, R. Mitchell; Galhena, Asiri S.; Fernandez, Facundo M.; Wang, May D.

    2016-01-01

    Traditional imaging techniques for studying the spatial distribution of biological molecules such as proteins, metabolites, and lipids, require the a priori selection of a handful of target molecules. Imaging mass spectrometry provides a means to analyze thousands of molecules at a time within a tissue sample, adding spatial detail to proteomic, metabolomic, and lipidomic studies. Compared to traditional microscopic images, mass spectrometric images have reduced spatial resolution and require a destructive acquisition process. In order to increase spatial detail, we propose a constrained acquisition path and signal degradation model enabling the use of a general image deblurring algorithm. Our analysis shows the potential of this approach and supports prior observations that the effect of the sprayer focuses on a central region much smaller than the extent of the spray. PMID:19963935

  5. 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.

  6. An Adaptively Accelerated Lucy-Richardson Method for Image Deblurring

    Directory of Open Access Journals (Sweden)

    Young-Hoon Kim

    2008-02-01

    Full Text Available We present an adaptively accelerated Lucy-Richardson (AALR method for the restoration of an image from its blurred and noisy version. The conventional Lucy-Richardson (LR method is nonlinear and therefore its convergence is very slow. We present a novel method to accelerate the existing LR method by using an exponent on the correction ratio of LR. This exponent is computed adaptively in each iteration, using first-order derivatives of the deblurred image from previous two iterations. Upon using this exponent, the AALR improves speed at the first stages and ensures stability at later stages of iteration. An expression for the estimation of the acceleration step size in AALR method is derived. The superresolution and noise amplification characteristics of the proposed method are investigated analytically. Our proposed AALR method shows better results in terms of low root mean square error (RMSE and higher signal-to-noise ratio (SNR, in approximately 43% fewer iterations than those required for LR method. Moreover, AALR method followed by wavelet-domain denoising yields a better result than the recently published state-of-the-art methods.

  7. 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.

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

    OpenAIRE

    Manpreet Kaur; Amandeep Singh Bhandari

    2014-01-01

    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 ...

  9. 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.

  10. 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...

  11. Blindness - resources

    Science.gov (United States)

    Resources - blindness ... The following organizations are good resources for information on blindness : American Foundation for the Blind -- www.afb.org Foundation Fighting Blindness -- www.blindness.org National Eye Institute -- ...

  12. 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.

  13. Image Deblurring Using Derivative Compressed Sensing for Optical Imaging Application

    CERN Document Server

    Rostami, Mohammad; Wang, Zhou

    2011-01-01

    Reconstruction of multidimensional signals from the samples of their partial derivatives is known to be a standard problem in inverse theory. Such and similar problems routinely arise in numerous areas of applied sciences, including optical imaging, laser interferometry, computer vision, remote sensing and control. Though being ill-posed in nature, the above problem can be solved in a unique and stable manner, provided proper regularization and relevant boundary conditions. In this paper, however, a more challenging setup is addressed, in which one has to recover an image of interest from its noisy and blurry version, while the only information available about the imaging system at hand is the amplitude of the generalized pupil function (GPF) along with partial observations of the gradient of GPF's phase. In this case, the phase-related information is collected using a simplified version of the Shack-Hartmann interferometer, followed by recovering the entire phase by means of derivative compressed sensing. Su...

  14. 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.

  15. 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.

  16. Blind restoration of retinal images degraded by space-variant blur with adaptive blur estimation

    Science.gov (United States)

    Marrugo, Andrés. G.; Millán, María. S.; Å orel, Michal; Å roubek, Filip

    2013-11-01

    Retinal images are often degraded with a blur that varies across the field view. Because traditional deblurring algorithms assume the blur to be space-invariant they typically fail in the presence of space-variant blur. In this work we consider the blur to be both unknown and space-variant. To carry out the restoration, we assume that in small regions the space-variant blur can be approximated by a space-invariant point-spread function (PSF). However, instead of deblurring the image on a per-patch basis, we extend individual PSFs by linear interpolation and perform a global restoration. Because the blind estimation of local PSFs may fail we propose a strategy for the identification of valid local PSFs and perform interpolation to obtain the space-variant PSF. The method was tested on artificial and real degraded retinal images. Results show significant improvement in the visibility of subtle details like small blood vessels.

  17. Blind Image Blur Estimation via Deep Learning.

    Science.gov (United States)

    Ruomei Yan; Ling Shao

    2016-04-01

    Image blur kernel estimation is critical to blind image deblurring. Most existing approaches exploit handcrafted blur features that are optimized for a certain uniform blur across the image, which is unrealistic in a real blind deconvolution setting, where the blur type is often unknown. To deal with this issue, we aim at identifying the blur type for each input image patch, and then estimating the kernel parameter in this paper. A learning-based method using a pre-trained deep neural network (DNN) and a general regression neural network (GRNN) is proposed to first classify the blur type and then estimate its parameters, taking advantages of both the classification ability of DNN and the regression ability of GRNN. To the best of our knowledge, this is the first time that pre-trained DNN and GRNN have been applied to the problem of blur analysis. First, our method identifies the blur type from a mixed input of image patches corrupted by various blurs with different parameters. To this aim, a supervised DNN is trained to project the input samples into a discriminative feature space, in which the blur type can be easily classified. Then, for each blur type, the proposed GRNN estimates the blur parameters with very high accuracy. Experiments demonstrate the effectiveness of the proposed method in several tasks with better or competitive results compared with the state of the art on two standard image data sets, i.e., the Berkeley segmentation data set and the Pascal VOC 2007 data set. In addition, blur region segmentation and deblurring on a number of real photographs show that our method outperforms the previous techniques even for non-uniformly blurred images. PMID:26930680

  18. 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...

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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...... willed blindness focusing on the development of either a new moral vision of our obligations or new visions of what a good life is....

  4. 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 ...

  5. 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-

  6. Vision - night blindness

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003039.htm Vision - night blindness To use the sharing features on ... page, please enable JavaScript. Night blindness is poor vision at night or in dim light. Considerations Night ...

  7. Onchocerciasis (River Blindness) FAQs

    Science.gov (United States)

    ... The CDC Parasites - Onchocerciasis (also known as River Blindness) Note: Javascript is disabled or is not supported ... infected Simulium blackfly. It is also called River Blindness because the fly that transmits infection breeds in ...

  8. Facts About Color Blindness

    Science.gov (United States)

    ... quickly diagnose specific types of color blindness. The Ishihara Color Test is the most common test for red-green ... red-green color blindness. The newer Cambridge Color Test uses a visual array similar to the Ishihara plates, except displayed on a computer monitor. The ...

  9. 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."

  10. 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)

  11. Models for the blind

    DEFF Research Database (Denmark)

    Olsén, Jan-Eric

    2014-01-01

    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......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...

  12. Change blindness images.

    Science.gov (United States)

    Ma, Li-Qian; Xu, Kun; Wong, Tien-Tsin; Jiang, Bi-Ye; Hu, Shi-Min

    2013-11-01

    Change blindness refers to human inability to recognize large visual changes between images. In this paper, we present the first computational model of change blindness to quantify the degree of blindness between an image pair. It comprises a novel context-dependent saliency model and a measure of change, the former dependent on the site of the change, and the latter describing the amount of change. This saliency model in particular addresses the influence of background complexity, which plays an important role in the phenomenon of change blindness. Using the proposed computational model, we are able to synthesize changed images with desired degrees of blindness. User studies and comparisons to state-of-the-art saliency models demonstrate the effectiveness of our model. PMID:24029902

  13. Blinded by Irrelevance: Pure Irrelevance Induced "Blindness"

    Science.gov (United States)

    Eitam, Baruch; Yeshurun, Yaffa; Hassan, Kinneret

    2013-01-01

    To what degree does our representation of the immediate world depend solely on its relevance to what we are currently doing? We examined whether relevance per se can cause "blindness," even when there is no resource limitation. In a novel paradigm, people looked at a colored circle surrounded by a differently colored ring--the task relevance of…

  14. The blind hens’ challenge

    DEFF Research Database (Denmark)

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

    2014-01-01

    about breeding blind hens. But we also argue that alternative views, which (for example) claim that it is important to respect the telos or rights of an animal, do not offer a more convincing solution to questions raised by the possibility of disenhancing animals for their own benefit.......Animal ethicists have recently debated the ethical questions raised by disenhancing animals to improve their welfare. Here, we focus on the particular case of breeding blind hens for commercial egg-laying systems, in order to benefit their welfare. Many people find breeding blind hens intuitively...

  15. 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....

  16. Blind Collective Signature Protocol

    Directory of Open Access Journals (Sweden)

    Nikolay A. Moldovyan

    2011-06-01

    Full Text Available Using the digital signature (DS scheme specified by Belarusian DS standard there are designed the collective and blind collective DS protocols. Signature formation is performed simultaneously by all of the assigned signers, therefore the proposed protocols can be used also as protocols for simultaneous signing a contract. The proposed blind collective DS protocol represents a particular implementation of the blind multisignature schemes that is a novel type of the signature schemes. The proposed protocols are the first implementations of the multisignature schemes based on Belarusian signature standard.

  17. 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...

  18. Blind loop syndrome

    Science.gov (United States)

    ... 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. 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?

  20. 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.

  1. Blind Analysis in Particle Physics

    OpenAIRE

    Roodman, Aaron

    2003-01-01

    A review of the blind analysis technique, as used in particle physics measurements, is presented. The history of blind analyses in physics is briefly discussed. Next the dangers of "experimenter's bias" and the advantages of a blind analysis are described. Three distinct kinds of blind analysis in particle physics are presented in detail. Finally, the BABAR collaboration's experience with the blind analysis technique is discussed.

  2. 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.

  3. 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...

  4. Multistage decomposition algorithm for blind source separation

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new algorithm for blind source separation is proposed, which only extracts the single independent component at each stage. The single independent component is acquired by an iterative algorithm for searching for the optimal solution of the defined cost function. Moreover, all the independent components are obtained by systematic multistage decomposition and multistage reconstruction. When there is spatially colored noise, the performance of this algorithm is advantageous over jointly approximated diagonalization of eigen-matrices (JADE). Simulated results show that if the number of source signals is more than 25, its computational complexity is lower than that of JADE.

  5. Learning Iteration-wise Generalized Shrinkage-Thresholding Operators for Blind Deconvolution.

    Science.gov (United States)

    Wangmeng Zuo; Dongwei Ren; Zhang, David; Shuhang Gu; Lei Zhang

    2016-04-01

    Salient edge selection and time-varying regularization are two crucial techniques to guarantee the success of maximum a posteriori (MAP)-based blind deconvolution. However, the existing approaches usually rely on carefully designed regularizers and handcrafted parameter tuning to obtain satisfactory estimation of the blur kernel. Many regularizers exhibit the structure-preserving smoothing capability, but fail to enhance salient edges. In this paper, under the MAP framework, we propose the iteration-wise ℓp-norm regularizers together with data-driven strategy to address these issues. First, we extend the generalized shrinkage-thresholding (GST) operator for ℓp-norm minimization with negative p value, which can sharpen salient edges while suppressing trivial details. Then, the iteration-wise GST parameters are specified to allow dynamical salient edge selection and time-varying regularization. Finally, instead of handcrafted tuning, a principled discriminative learning approach is proposed to learn the iterationwise GST operators from the training dataset. Furthermore, the multi-scale scheme is developed to improve the efficiency of the algorithm. Experimental results show that, negative p value is more effective in estimating the coarse shape of blur kernel at the early stage, and the learned GST operators can be well generalized to other dataset and real world blurry images. Compared with the state-of-the-art methods, our method achieves better deblurring results in terms of both quantitative metrics and visual quality, and it is much faster than the state-of-the-art patch-based blind deconvolution method. PMID:26915121

  6. Blind Friendly Maps

    OpenAIRE

    Červenka, Petr; Břinda, Karel; Seifert, Radek; Hofman, Petr

    2016-01-01

    Space concept of the surrounding area is one of the most important preconditions of the independent mobility and orientation of the blind people. Tactile maps are considered to be the most appropriate source of spatial information. One of the main problems of the tactile maps usage is their problematic accessibility for the blind users since they are not available in time and with up-to-date content. The map production is a matter of tedious manual work and a result of expensive and time-cons...

  7. 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...

  8. Testing Children for Color Blindness

    Science.gov (United States)

    ... Español Eye Health / News Testing Children for Color Blindness Written by: Shirley Dang Apr. 03, 2014 New ... shows that kids can be tested for color blindness as soon as age 4, finds Caucasian boys ...

  9. 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...

  10. 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...

  11. 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.

  12. [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

  13. 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.

  14. 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

  15. 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.

  16. 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...

  17. Laryngopharyngeal reconstruction

    OpenAIRE

    Kazi, Rehan A

    2006-01-01

    There is a high incidence of hypopharyngeal cancer is our country due to the habits of tobacco and alcohol. Moreover these cases are often detected in the late stages thereby making the issue of reconstruction very tedious and unpredictable. There are a number of options for laryngopharyngeal reconstruction available now including the use of microvascular flaps depending upon the patient’s fitness, motivation, technical expertise, size and extent of the defect. This article reviews the differ...

  18. Noise blind test

    OpenAIRE

    H. Cadet

    2006-01-01

    In the aim of characterizing site condition for seismic risk, the microtremor or ambient noise studies have been developed. The main objective of this blind test is to check of the reliability of results, to observe the user subjectivity (array choice, parameters that are user depend) in the noise recordings analyze. Noise records were analysed on single-station with H/V method and with several sensors for array method to determine the dispersion characteristics of the surface-wave part of th...

  19. FLIPPS for the Blind

    DEFF Research Database (Denmark)

    Bothe, Hans-Heinrich; Al-Hamdani, Sermed

    2010-01-01

    The idea of FLIPPS is to design, implement, and evaluate a vibro-tactile device that is composed of a photo diode, vibro-tactile stimulator, microcontroller and power supply. The stimulator is attached to the finger tip and activated when light illumination exceeds a defined threshold. The subject...... (blind person) receives the reflected light from the objects and, based on brain plasticity principles, can interactively learn to construct a mental image of the objects and of the scenery. The FLIPPS idea is based on sensory substitution theory; here, substituting visual inputs by haptic vibrations....

  20. Rapid, Robust, and Reliable Blind Deconvolution via Nonconvex Optimization

    OpenAIRE

    Li, Xiaodong; Ling, Shuyang; Strohmer, Thomas; Wei, Ke

    2016-01-01

    We study the question of reconstructing two signals $f$ and $g$ from their convolution $y = f\\ast g$. This problem, known as {\\em blind deconvolution}, pervades many areas of science and technology, including astronomy, medical imaging, optics, and wireless communications. A key challenge of this intricate non-convex optimization problem is that it might exhibit many local minima. We present an efficient numerical algorithm that is guaranteed to recover the exact solution, when the number of ...

  1. The whole story behind blind adaptive equalizers/blind deconvolution

    CERN Document Server

    Pinchas, Monika

    2012-01-01

    This e-book covers a variety of blind deconvolution/equalization methods based on both cost functions and Bayes rules where simulation results are supplied to support the theory - including Maximum Entropy density approximation technique and the Edgeworth Expansion approach used in various blind equalizers.

  2. 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

  3. Overview on Deaf-Blindness

    Science.gov (United States)

    Miles, Barbara

    2008-01-01

    It may seem that deaf-blindness refers to a total inability to see or hear. However, in reality deaf-blindness is a condition in which the combination of hearing and visual losses in children cause "such severe communication and other develop mental and educational needs that they cannot be accommodated in special education programs solely for…

  4. 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.

  5. 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 ...

  6. Blind Known Interference Cancellation

    CERN Document Server

    Zhang, Shengli; Wang, Hui

    2011-01-01

    This paper investigates interference-cancellation schemes at the receiver, in which the original data of the interference is known a priori. Such a priori knowledge is common in wireless relay networks. For example, a transmitting relay could be relaying data that was previously transmitted by a node, in which case the interference received by the node now is actually self information. Besides the case of self information, the node could also have overheard or received the interference data in a prior transmission by another node. Directly removing the known interference requires accurate estimate of the interference channel, which may be difficult in many situations. In this paper, we propose a novel scheme, Blind Known Interference Cancellation (BKIC), to cancel known interference without interference channel information. BKIC consists of two steps. The first step combines adjacent symbols to cancel the interference, exploiting the fact that the channel coefficients are almost the same between successive sy...

  7. Project Reconstruct.

    Science.gov (United States)

    Helisek, Harriet; Pratt, Donald

    1994-01-01

    Presents a project in which students monitor their use of trash, input and analyze information via a database and computerized graphs, and "reconstruct" extinct or endangered animals from recyclable materials. The activity was done with second-grade students over a period of three to four weeks. (PR)

  8. Vaginal reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Lesavoy, M.A.

    1985-05-01

    Vaginal reconstruction can be an uncomplicated and straightforward procedure when attention to detail is maintained. The Abbe-McIndoe procedure of lining the neovaginal canal with split-thickness skin grafts has become standard. The use of the inflatable Heyer-Schulte vaginal stent provides comfort to the patient and ease to the surgeon in maintaining approximation of the skin graft. For large vaginal and perineal defects, myocutaneous flaps such as the gracilis island have been extremely useful for correction of radiation-damaged tissue of the perineum or for the reconstruction of large ablative defects. Minimal morbidity and scarring ensue because the donor site can be closed primarily. With all vaginal reconstruction, a compliant patient is a necessity. The patient must wear a vaginal obturator for a minimum of 3 to 6 months postoperatively and is encouraged to use intercourse as an excellent obturator. In general, vaginal reconstruction can be an extremely gratifying procedure for both the functional and emotional well-being of patients.

  9. Vaginal reconstruction

    International Nuclear Information System (INIS)

    Vaginal reconstruction can be an uncomplicated and straightforward procedure when attention to detail is maintained. The Abbe-McIndoe procedure of lining the neovaginal canal with split-thickness skin grafts has become standard. The use of the inflatable Heyer-Schulte vaginal stent provides comfort to the patient and ease to the surgeon in maintaining approximation of the skin graft. For large vaginal and perineal defects, myocutaneous flaps such as the gracilis island have been extremely useful for correction of radiation-damaged tissue of the perineum or for the reconstruction of large ablative defects. Minimal morbidity and scarring ensue because the donor site can be closed primarily. With all vaginal reconstruction, a compliant patient is a necessity. The patient must wear a vaginal obturator for a minimum of 3 to 6 months postoperatively and is encouraged to use intercourse as an excellent obturator. In general, vaginal reconstruction can be an extremely gratifying procedure for both the functional and emotional well-being of patients

  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...... enables us to see ourselves as moral beings although our lack of reaction to the effects of our actions tells another story. The consequences, especially to animal welfare are outlined and it is briefly discussed whether a solution lies in a new moral vision of our obligations or a new vision of what...

  11. Radio Reconstructions

    OpenAIRE

    Bulley, James; Jones, Daniel

    2013-01-01

    Radio Reconstructions is a sound installation which use indeterminate radio broadcasts as its raw material. Each piece is structured by a notated score, which controls its rhythm, dynamics and melodic contour over time. The audio elements used to enact this score are selected in real-time from unknown radio transmissions, by an autonomous software system which is continuously scanning the radio waves in search of similar fragments of audio. Using a technique known as audio mosaicing, hund...

  12. 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

  13. Laboratory Techniques for the Blind

    Science.gov (United States)

    Tombaugh, Dorothy

    1972-01-01

    Describes modifications of laboratory procedures for the BSCS Green Version biology, including dissection, microbiology, animal behavior, physiology, biochemistry, and genetics that make the methods suitable for direct experimentation by blind students. Discusses models as substitutes for microscopy. (AL)

  14. Student Art for Blind Children.

    Science.gov (United States)

    Vanda, Kay

    1982-01-01

    Describes a project in which high school student volunteers designed art activities for blind children. Students incorporated the sensation of motion and texture into their designs for toys, puzzles, games, and story illustrations. (AM)

  15. American Foundation for the Blind

    Science.gov (United States)

    ... celebrate and support a workforce that is fully inclusive of people who are blind or visually impaired. 5 great ways to celebrate National Disability Employment Awareness Month College Bound? Transitioning to college and ...

  16. 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....

  17. What It's Like to Be Color Blind

    Science.gov (United States)

    ... Homework? Here's Help White House Lunch Recipes 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 ...

  18. 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.

  19. 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.

  20. An alternating minimization method for blind deconvolution from Poisson data

    International Nuclear Information System (INIS)

    Blind deconvolution is a particularly challenging inverse problem since information on both the desired target and the acquisition system have to be inferred from the measured data. When the collected data are affected by Poisson noise, this problem is typically addressed by the minimization of the Kullback-Leibler divergence, in which the unknowns are sought in particular feasible sets depending on the a priori information provided by the specific application. If these sets are separated, then the resulting constrained minimization problem can be addressed with an inexact alternating strategy. In this paper we apply this optimization tool to the problem of reconstructing astronomical images from adaptive optics systems, and we show that the proposed approach succeeds in providing very good results in the blind deconvolution of nondense stellar clusters

  1. Tracheal reconstructions.

    Science.gov (United States)

    Srikrishna, S V; Shekar, P S; Shetty, N

    1998-12-01

    Surgical reconstruction of the trachea is a relatively complex procedure. We had 20 cases of tracheal stenosis. We have a modest experience of 16 tracheal reconstructions for acquired tracheal stenosis. Two patients underwent laser treatment while another two died before any intervention. The majority of these cases were a result of prolonged ventilation (14 cases), following organophosphorous poisoning (11 cases), Guillain-Barré syndrome, bullet injury, fat embolism and surprisingly only one tumor, a case of mucoepidermoid carcinoma, who had a very unusual presentation. There were 12 males and 4 females in this series, age ranging from 12-35 years. The duration of ventilation ranged from 1-21 days and the interval from decannulation to development of stridor was between 5-34 days. Six of them were approached by the cervical route, 5 by thoracotomy and cervical approach, 2 via median sternotomy and 3 by thoracotomy alone. Five of them required an additional laryngeal drop and 1 required pericardiotomy and release of pulmonary veins to gain additional length. The excised segments of trachea measured 3 to 5 cms in length. All were end to end anastomosis with interrupted Vicryl sutures. We have had no experience with stents or prosthetic tubes. Three patients developed anastomotic leaks which were controlled conservatively. Almost all of them required postoperative tracheo-bronchial suctioning with fibreoptic bronchoscope. We had one death in this series due to sepsis. PMID:9914459

  2. 20 CFR 416.983 - How we evaluate statutory blindness.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false How we evaluate statutory blindness. 416.983... AGED, BLIND, AND DISABLED Determining Disability and Blindness Blindness § 416.983 How we evaluate statutory blindness. We will find that you are blind if you are statutorily blind within the meaning...

  3. 20 CFR 416.982 - Blindness under a State plan.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Blindness under a State plan. 416.982 Section..., BLIND, AND DISABLED Determining Disability and Blindness Blindness § 416.982 Blindness under a State... plan because of your blindness for the month of December 1973; and (c) You continue to be blind...

  4. [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

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

    OpenAIRE

    Arthur I. Karshmer; 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...

  6. 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....

  7. 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.

  8. PROXY BLIND SIGNATURE BASED ON ECDLP

    Directory of Open Access Journals (Sweden)

    SATARUPA PRADHAN,

    2011-03-01

    Full Text Available Proxy blind signature combines the properties of both proxy signature and blind signature. In a proxy signature scheme, a signer delegates his signing power to a proxy, who signs a message on behalf of the original signer. In a blind signature scheme, the signer cannot link the relationship between the blind message and the signature of the chosen message. Therefore, it is very suitable for electronic commerceapplication. In this paper, a proxy blind signature scheme based on ECDLP (Elliptic Curve Discrete Logarithm Problem has been proposed, which satisfy the security properties of both the blind signature and the proxy signature. Analysis shows that our scheme is secure and efficient.

  9. 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.

  10. [The punishment of blinding and the life of the blind].

    Science.gov (United States)

    Büttner, Jan Ulrich

    2009-01-01

    The article deals with a group of people who were deprived of their eyesight by private acts of force or by executions of lawful sentences. In early medieval texts blinding is frequently mentioned in connection with popes, kings, princes or bishops. However, since the High Middle Ages these dignitaries were increasingly spared the loss of their eyes. It may be said that on the whole, from the eighth to the twelfth century, blinding was overwhelmingly used to dispose of political adversaries, but did then rapidly turn into a criminal punishment. In the earliest 'Landfriedensordnungen' of the late eleventh century, the loss of the perpetrator's eyes crops up as punishment for breach of the peace, while later it was applied to a variety of more or less serious offences. The destiny of the blinded in the early Middle Ages is only highlighted by sketches of a few individual cases; for the High and late Middle Ages--apart from a few notable exceptions--it is only possible to reflect on the general situation of blind people in society, since the sources usually do not differentiate between those having lost their sight through human violence or due to other causes. PMID:20506724

  11. 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

  12. 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...

  13. 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.

  14. 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.

  15. Blindness Biggest Fear for Many Americans

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_160254.html Blindness Biggest Fear for Many Americans Losing vision would ... 4, 2016 THURSDAY, Aug. 4, 2016 (HealthDay News) -- Blindness is what many Americans fear most, a new ...

  16. 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 and...

  17. 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...

  18. Overview on Deaf-Blindness

    Science.gov (United States)

    ... reading lip-reading speech Along with nonverbal and verbal conversations, a child who is deaf-blind needs a reliable routine of meaningful activities, and some way or ways that this routine can be communicated to her or him. Touch cues, gestures, and use of object symbols are some ...

  19. Vesicouterine fistula and blind vagina

    International Nuclear Information System (INIS)

    A case of vesicouterine fistula with blind vagina following cesarean section for obstructed labor is presented. It was surgically treated by fistulectomy, cervicoplasty and maintenance of bladder and cervical potency by catheterization. Intrauterine synechiae formation was prevented by copper T insertion and oral contraceptive pills. The patient is making uneventful a symptomatic progress planning to conceive. (author)

  20. 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?

  1. 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...

  2. Resources for Visually Impaired or Blind Students.

    Science.gov (United States)

    Hart, Elizabeth

    2000-01-01

    Suggests resources for school librarians who need materials for visually impaired or blind students. Highlights include the National Library Service for the Blind and Physically Handicapped; Louis Database of Accessible Materials for People Who Are Blind or Visually Impaired; Braille books; large print books, audio books; assistive technology; and…

  3. 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...

  4. 45 CFR 233.70 - Blindness.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 2 2010-10-01 2010-10-01 false Blindness. 233.70 Section 233.70 Public Welfare... FINANCIAL ASSISTANCE PROGRAMS § 233.70 Blindness. (a) State plan requirements. A State plan under title X or XVI of the Social Security Act must: (1) Contain a definition of blindness in terms of...

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. Blindness and severe visual impairment in pupils at schools for the blind in Burundi

    OpenAIRE

    Patrick Ruhagaze; Kahaki Kimani Margaret Njuguna; Lévi Kandeke; Paul Courtright

    2013-01-01

    Purpose: To determine the causes of childhood blindness and severe visual impairment in pupils attending schools for the blind in Burundi in order to assist planning for services in the country. Materials and Methods: All pupils attending three schools for the blind in Burundi were examined. A modified WHO/PBL eye examination record form for children with blindness and low vision was used to record the findings. Data was analyzed for those who became blind or severely visually impaired be...

  10. Rapid Assessment of Avoidable Blindness in Western Rwanda: Blindness in a Postconflict Setting

    OpenAIRE

    Wanjiku Mathenge; John Nkurikiye; Hans Limburg; Hannah Kuper

    2007-01-01

    Editors' Summary Background. VISION 2020, a global initiative that aims to eliminate avoidable blindness, has estimated that 75% of blindness worldwide is treatable or preventable. The WHO estimates that in Africa, around 9% of adults aged over 50 are blind. Some data suggest that people living in regions affected by violent conflict are more likely to be blind than those living in unaffected regions. Currently no data exist on the likely prevalence of blindness in Rwanda, a central African c...

  11. 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.

  12. 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.

  13. 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.

  14. Sensory augmentation for the blind

    Directory of Open Access Journals (Sweden)

    Silke Manuela Kärcher

    2012-03-01

    Full Text Available Enacted theories of consciousness conjecture that perception and cognition arise from an active experience of the regular relations that are tying together the sensory stimulation of different modalities and associated motor actions. Previous experiments investigated this concept by employing the technique of sensory substitution. Building on these studies, here we test a set of hypotheses derived from this framework and investigate the utility of sensory augmentation in handicapped people. We provide a late blind subject with a new set of sensorimotor laws: A vibro-tactile belt continually signals the direction of magnetic north. The subject completed a set of behavioral tests before and after an extended training period. The tests were complemented by questionnaires and interviews. This newly supplied information improved performance on different time scales. In a pointing task we demonstrate an instant improvement of performance based on the signal provided by the device. Furthermore, the signal was helpful in relevant daily tasks, often complicated for the blind, such as keeping a direction over longer distances or taking shortcuts in familiar environments. A homing task with an additional attentional load demonstrated a significant improvement after training. The subject found the directional information highly expedient for the adjustment of his inner maps of familiar environments and describes an increase in his feeling of security when exploring unfamiliar environments with the belt. The results give evidence for a firm integration of the newly supplied signals into the behavior of this late blind subject with better navigational performance and more courageous behavior in unfamiliar environments. Most importantly, the complementary information provided by the belt lead to a positive emotional impact with enhanced feeling of security. This experimental approach demonstrates the potential of sensory augmentation devices for the help of

  15. Blindness. [prosthetic devices and sensory aids

    Science.gov (United States)

    Pudenz, R. H.

    1974-01-01

    The possibilities are considered that modern electronics and engineering have to offer the individual with a damaged or disordered nervous system, especially the blind person. Discussed are the incidence and principal causes of blindness, past research activities, and a capsule review of some of the more interesting programs designed to provide the blind with the ability to be mobile in their environment and to read printed matter.

  16. 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.

  17. Application of Behavior Modification to Blind Children.

    Science.gov (United States)

    Hayes, Charles S.; Weinhouse, Ellen

    1978-01-01

    Research and application of principles of behavior modification with visually impaired and blind children are reviewed with particular attention to lower functioning multiply impaired children. (Author)

  18. Enhanced heat discrimination in congenital blindness

    DEFF Research Database (Denmark)

    Slimani, Hocine; Ptito, Maurice; Kupers, Ron

    2015-01-01

    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...... trials (ΔT = 0°C) were also included to test for false positive responses. We used signal detection theory model to analyze the data. Our data revealed that blind participants have a higher accuracy than the sighted (d': Blind=2.4 ± 1.0, Sighted=1.8 ± 0.7, p=0.025), regardless of the size...

  19. 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.

  20. 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.

  1. Breast Reconstruction After Mastectomy

    Science.gov (United States)

    ... reconstruction with or without radiotherapy. Current Opinion in Obstetrics and Gynecology 2011;23(1):44–50. [PubMed Abstract] Barry M, Kell MR. Radiotherapy and breast reconstruction: a meta-analysis. Breast ...

  2. 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.

  3. 42 CFR 436.531 - Determination of blindness.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Determination of blindness. 436.531 Section 436.531... Requirements for Medicaid Eligibility Blindness § 436.531 Determination of blindness. In determining blindness... determine on behalf of the agency— (1) Whether the individual meets the definition of blindness; and...

  4. 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

  5. 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...--that are accessible to people who are blind or have vision loss; technical obstacles, if any, to...

  6. 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.

  7. 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.

  8. Economic burden of blindness in India

    Directory of Open Access Journals (Sweden)

    Shamanna B

    1998-01-01

    Full Text Available Economic analysis is one way to determine the allocation of scarce resources for health-care programs. The initial step in this process is to estimate in economic terms the burden of diseases and the benefit from interventions for prevention and treatment of these diseases. In this paper, the direct and indirect economic loss due to blindness in India is calculated on the basis of certain assumptions. The cost of treating cataract blindness in India is estimated at current prices. The economic burden of blindness in India for the year 1997 based on our assumptions is Rs. 159 billion (US$ 4.4 billion, and the cumulative loss over lifetime of the blind is Rs. 2,787 billion (US$ 77.4 billion. Childhood blindness accounts for 28.7% of this lifetime loss. The cost of treating all cases of cataract blindness in India is Rs. 5.3 billion (US$ 0.15 billion. Similar estimates for causes of blindness other than cataract have to be made in order to develop a comprehensive approach to deal with blindness in India.

  9. Individual Differences in Susceptibility to Inattentional Blindness

    Science.gov (United States)

    Seegmiller, Janelle K.; Watson, Jason M.; Strayer, David L.

    2011-01-01

    Inattentional blindness refers to the finding that people do not always see what appears in their gaze. Though inattentional blindness affects large percentages of people, it is unclear if there are individual differences in susceptibility. The present study addressed whether individual differences in attentional control, as reflected by…

  10. Mentoring Transition-Age Youth with Blindness

    Science.gov (United States)

    Bell, Edward C.

    2012-01-01

    This article reports on a mentoring project designed for transition-age youth (ages 16-26) who are persons with legal blindness. Youth were matched with adult mentors who were also persons with blindness but who have achieved academic and career success. Results demonstrate that youth who participated in the project for 2 years had significant…

  11. 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.

  12. 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.

  13. 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 ...

  14. Genetics Home Reference: autosomal dominant congenital stationary night blindness

    Science.gov (United States)

    ... stationary night blindness autosomal dominant congenital stationary night blindness Enable Javascript to view the expand/collapse boxes. ... Close All Description Autosomal dominant congenital stationary night blindness is a disorder of the retina , which is ...

  15. Genetics Home Reference: X-linked congenital stationary night blindness

    Science.gov (United States)

    ... stationary night blindness X-linked congenital stationary night blindness Enable Javascript to view the expand/collapse boxes. ... Close All Description X-linked congenital stationary night blindness is a disorder of the retina , which is ...

  16. 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.

  17. 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.

  18. 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.

  19. Blindness in designing intelligent systems

    Science.gov (United States)

    Denning, Peter J.

    1988-01-01

    New investigations of the foundations of artificial intelligence are challenging the hypothesis that problem solving is the cornerstone of intelligence. New distinctions among three domains of concern for humans--description, action, and commitment--have revealed that the design process for programmable machines, such as expert systems, is based on descriptions of actions and induces blindness to nonanalytic action and commitment. Design processes focusing in the domain of description are likely to yield programs like burearcracies: rigid, obtuse, impersonal, and unable to adapt to changing circumstances. Systems that learn from their past actions, and systems that organize information for interpretation by human experts, are more likely to be successful in areas where expert systems have failed.

  20. 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.

  1. 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.

  2. 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...

  3. Re-construction

    OpenAIRE

    Bernadette Marie Devilat

    2013-01-01

    Re-construct: to build again. The necessary reconstruction process after an earthquake can be seen as an opportunity to improve previous conditions. All damaged buildings undergo a renovation process in which every piece is carefully returned to its original place. The photograph shows roof reconstruction work in San Pedro de Alcántara, a heritage area in the central valley of Chile, which was particularly affected by the 2010 earthquake. 

  4. Temperature reconstruction analysis

    CERN Document Server

    Scafetta, N; Grigolini, P; Roberts, J; Scafetta, Nicola; Imholt, Tim; Grigolini, Paolo; Roberts, Jim

    2002-01-01

    This paper presents a wavelet multiresolution analysis of a time series dataset to study the correlation between the real temperature data and three temperature model reconstructions at different scales. We show that the Mann et.al. model reconstructs the temperature better at all temporal resolutions. We show and discuss the wavelet multiresolution analysis of the Mann's temperature reconstruction for the period from 1400 to 2000 A.D.E.

  5. 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

  6. 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.

  7. Flexor pulley reconstruction.

    Science.gov (United States)

    Dy, Christopher J; Daluiski, Aaron

    2013-05-01

    Flexor pulley reconstruction is a challenging surgery. Injuries often occur after traumatic lacerations or forceful extension applied to an acutely flexed finger. Surgical treatment is reserved for patients with multiple closed pulley ruptures, persistent pain, or dysfunction after attempted nonoperative management of a single pulley rupture, or during concurrent or staged flexor tendon repair or reconstruction. If the pulley cannot be repaired primarily, pulley reconstruction can be performed using graft woven into remnant pulley rim or looping graft around the phalanx. Regardless of the reconstructive technique, the surgeon should emulate the length, tension, and glide of the native pulley. PMID:23660059

  8. Blind extraction of exoplanetary spectra

    Science.gov (United States)

    Morello, Giuseppe; Waldmann, Ingo P.; Tinetti, Giovanna

    2016-06-01

    In the last decade, remote sensing spectroscopy enabled characterization of the atmospheres of extrasolar planets. Transmission and emission spectra of tens of transiting exoplanets have been measured with multiple instruments aboard Spitzer and Hubble Space Telescopes as well as ground-based facilities, revealing the presence of atomic, ionic and molecular species in their atmospheres, and constraining their temperature and pressure profiles.Early analyses were somehow heuristic both in measuring the spectra and in their interpretation, leading to some controversies in the literature.A photometric precision of 0.01% is necessary to detect the atmospheric spectral modulations. Current observatories, except Kepler, were not designed to achieve this precision. Data reduction is necessary to minimize the effect of instrument systematics in order to achieve the target precision. In the past, parametric models have extensively been used by most teams to remove correlated noise with the aid of auxiliary information of the instrument, the so-called optical state vectors (OSVs). Such OSVs can include inter- and intra-pixel position of the star or its spectrum, instrument temperatures and inclinations, and/or other parameters. In some cases, different parameterizations led to discrepant results.We recommend the use of blind non-parametric data detrending techniques to overcome those issues. In particular, we adopt Independent Component Analysis (ICA), i.e. a blind source separation (BSS) technique to disentangle the multiple instrument systematics and astrophysical signals in transit/eclipse light curves. ICA does not require a model for the systematics, and for this reason, it can be applied to any instrument with little changes, if any. ICA-based algorithms have been applied to Spitzer/IRAC and synthetic observations in photometry (Morello et al. 2014, 2015, 2016; Morello 2015) and to Hubble/NICMOS and Spitzer/IRS in spectroscopy (Waldmann 2012, 2014, Waldmann et al. 2013

  9. Iterated Gate Teleportation and Blind Quantum Computation.

    Science.gov (United States)

    Pérez-Delgado, Carlos A; Fitzsimons, Joseph F

    2015-06-01

    Blind quantum computation allows a user to delegate a computation to an untrusted server while keeping the computation hidden. A number of recent works have sought to establish bounds on the communication requirements necessary to implement blind computation, and a bound based on the no-programming theorem of Nielsen and Chuang has emerged as a natural limiting factor. Here we show that this constraint only holds in limited scenarios, and show how to overcome it using a novel method of iterated gate teleportations. This technique enables drastic reductions in the communication required for distributed quantum protocols, extending beyond the blind computation setting. Applied to blind quantum computation, this technique offers significant efficiency improvements, and in some scenarios offers an exponential reduction in communication requirements. PMID:26196609

  10. Ask a Scientist: What is Color Blindness?

    Medline Plus

    Full Text Available ... Scientist Video Series Why can’t you see colors well in the dark? Do fish have eyelids? ... video series. Dr. Sheldon Miller answers questions about color blindness, whether it can be treated, and how ...

  11. Assertive Skills Training for the Blind.

    Science.gov (United States)

    Everhart, Gary; And Others

    1980-01-01

    The article describes how a rehabilitation center for the blind, aware that many clients were inept in dealing with society at large, instituted an assertive skills training program to improve client skills in this area. (Author/SBH)

  12. 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

  13. 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.

  14. Haptic graphs for blind computer users

    OpenAIRE

    Yu, W; Ramloll, R.; Brewster, S.A.

    2001-01-01

    In this paper we discuss the design of computer-based haptic graphs for blind and visually impaired people with the support of our preliminary experimental results. Since visual impairment makes data visualisation techniques inappropriate for blind people, we are developing a system that can make graphs accessible through haptic and audio media. The disparity between human haptic perception and the sensation simulated by force feedback devices is discussed. Our strategies to tackle technical ...

  15. New Certificateless Blind Ring Signature Scheme

    Directory of Open Access Journals (Sweden)

    Hua Sun

    2013-07-01

    Full Text Available A new certificateless blind ring signature scheme was proposed in this paper. The scheme could not only avoid the problem of certificate management of public key certificate cryptography, but also overcome the inherent key-escrow problem of identity-based public key cryptography. In the last, by using bilinear pairing technique, it was proved that this scheme satisfied the security of existential unforgeability, blindness and unconditional anonymity.

  16. 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.

  17. 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....

  18. Blind Alley Aware ACO Routing Algorithm

    Science.gov (United States)

    Yoshikawa, Masaya; Otani, Kazuo

    2010-10-01

    The routing problem is applied to various engineering fields. Many researchers study this problem. In this paper, we propose a new routing algorithm which is based on Ant Colony Optimization. The proposed algorithm introduces the tabu search mechanism to escape the blind alley. Thus, the proposed algorithm enables to find the shortest route, even if the map data contains the blind alley. Experiments using map data prove the effectiveness in comparison with Dijkstra algorithm which is the most popular conventional routing algorithm.

  19. Reduced taste sensitivity in congenital blindness

    DEFF Research Database (Denmark)

    Gagnon, Lea; Kupers, Ron; Ptito, Maurice

    2013-01-01

    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......-related obstacles when shopping for food, cooking and eating out, all of which contribute to underexpose the gustatory system to a larger variety of taste stimuli....

  20. 42 CFR 435.530 - Definition of blindness.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Definition of blindness. 435.530 Section 435.530... ISLANDS, AND AMERICAN SAMOA Categorical Requirements for Eligibility Blindness § 435.530 Definition of blindness. (a) Definition. The agency must use the same definition of blindness as used under SSI,...

  1. 42 CFR 436.530 - Definition of blindness.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Definition of blindness. 436.530 Section 436.530... Requirements for Medicaid Eligibility Blindness § 436.530 Definition of blindness. (a) Definition. The agency must use the definition of blindness that is used in the State plan for AB or AABD. (b) State...

  2. Image Reconstruction. Chapter 13

    International Nuclear Information System (INIS)

    This chapter discusses how 2‑D or 3‑D images of tracer distribution can be reconstructed from a series of so-called projection images acquired with a gamma camera or a positron emission tomography (PET) system [13.1]. This is often called an ‘inverse problem’. The reconstruction is the inverse of the acquisition. The reconstruction is called an inverse problem because making software to compute the true tracer distribution from the acquired data turns out to be more difficult than the ‘forward’ direction, i.e. making software to simulate the acquisition. There are basically two approaches to image reconstruction: analytical reconstruction and iterative reconstruction. The analytical approach is based on mathematical inversion, yielding efficient, non-iterative reconstruction algorithms. In the iterative approach, the reconstruction problem is reduced to computing a finite number of image values from a finite number of measurements. That simplification enables the use of iterative instead of mathematical inversion. Iterative inversion tends to require more computer power, but it can cope with more complex (and hopefully more accurate) models of the acquisition process

  3. 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.

  4. 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.

  5. The Blinds Shop Company Limited Brand Identity Project

    OpenAIRE

    Dee, Peter

    2008-01-01

    The Blinds Shop offers made to measure window blinds catering to all markets across Ireland. The Blinds Shop required a clean, bold and modern logo using fresh colours and imagery. Peter Dee - Strategic Design and Marketing Consultant, was responsible for the design and development of the brand identity for the The Blinds Shop Company Limited which was used on business cards, letterhead, promotional information, uniforms, advertising and e-Commerce website. The Blinds Shop is a retailer...

  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. Blindness and severe visual impairment in pupils at schools for the blind in Burundi

    Directory of Open Access Journals (Sweden)

    Patrick Ruhagaze

    2013-01-01

    Full Text Available Purpose: To determine the causes of childhood blindness and severe visual impairment in pupils attending schools for the blind in Burundi in order to assist planning for services in the country. Materials and Methods: All pupils attending three schools for the blind in Burundi were examined. A modified WHO/PBL eye examination record form for children with blindness and low vision was used to record the findings. Data was analyzed for those who became blind or severely visually impaired before the age of 16 years. Results: Overall, 117 pupils who became visually impaired before 16 years of age were examined. Of these, 109 (93.2% were blind or severely visually impaired. The major anatomical cause of blindness or severe visual impairment was cornea pathology/phthisis (23.9%, followed by lens pathology (18.3%, uveal lesions (14.7% and optic nerve lesions (11.9%. In the majority of pupils with blindness or severe visual impairment, the underlying etiology of visual loss was unknown (74.3%. More than half of the pupils with lens related blindness had not had surgery; among those who had surgery, outcomes were generally poor. Conclusion: The causes identified indicate the importance of continuing preventive public health strategies, as well as the development of specialist pediatric ophthalmic services in the management of childhood blindness in Burundi. The geographic distribution of pupils at the schools for the blind indicates a need for community-based programs to identify and refer children in need of services.

  8. 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…

  9. Acromioclavicular Joint Reconstruction.

    Science.gov (United States)

    Scillia, Anthony J; Cain, E Lyle

    2015-12-01

    Our technique for acromioclavicular joint reconstruction provides a variation on coracoclavicular ligament reconstruction to also include acromioclavicular ligament reconstruction. An oblique acromial tunnel is drilled, and the medial limb of the gracilis graft, after being crossed and passed beneath the coracoid and through the clavicle, is passed through this acromial tunnel and sutured to the trapezoid graft limb after appropriate tensioning. Tenodesis screws are not placed in the bone tunnels to avoid graft fraying, and initial forces on the graft are offloaded with braided absorbable sutures passed around the clavicle. PMID:27284528

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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...

  15. Overview of Image Reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Marr, R. B.

    1980-04-01

    Image reconstruction (or computerized tomography, etc.) is any process whereby a function, f, on Rn is estimated from empirical data pertaining to its integrals, ∫f(x) dx, for some collection of hyperplanes of dimension k < n. The paper begins with background information on how image reconstruction problems have arisen in practice, and describes some of the application areas of past or current interest; these include radioastronomy, optics, radiology and nuclear medicine, electron microscopy, acoustical imaging, geophysical tomography, nondestructive testing, and NMR zeugmatography. Then the various reconstruction algorithms are discussed in five classes: summation, or simple back-projection; convolution, or filtered back-projection; Fourier and other functional transforms; orthogonal function series expansion; and iterative methods. Certain more technical mathematical aspects of image reconstruction are considered from the standpoint of uniqueness, consistency, and stability of solution. The paper concludes by presenting certain open problems. 73 references. (RWR)

  16. 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...... for oncoplastic and reconstructive breast surgery and will certainly become an invaluable addition to breast reconstructive methods....

  17. Delayed breast implant reconstruction

    DEFF Research Database (Denmark)

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

    2011-01-01

    Studies of complications following reconstructive surgery with implants among women with breast cancer are needed. As the, to our knowledge, first prospective long-term study we evaluated the occurrence of complications following delayed breast reconstruction separately for one- and two......-stage procedures. From the Danish Registry for Plastic Surgery of the Breast, which has prospectively registered data for women undergoing breast implantations since 1999, we identified 559 women without a history of radiation therapy undergoing 592 delayed breast reconstructions following breast cancer during...... of reoperation was significantly higher following the one-stage procedure. For both procedures, the majority of reoperations were due to asymmetry or displacement of the implant. In conclusion, non-radiated one- and two-stage delayed breast implant reconstructions are associated with substantial risks...

  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

    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...

  20. 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.

  1. Reconstructing baryon oscillations

    OpenAIRE

    Noh, Yookyung; White, Martin; Padmanabhan, Nikhil

    2009-01-01

    The baryon acoustic oscillation (BAO) method for constraining the expansion history is adversely affected by non-linear structure formation, which washes out the correlation function peak created at decoupling. To increase the constraining power of low z BAO experiments, it has been proposed that one use the observed distribution of galaxies to "reconstruct'' the acoustic peak. Recently Padmanabhan, White and Cohn provided an analytic formalism for understanding how reconstruction works withi...

  2. Reconstruction after mastectomy.

    Science.gov (United States)

    Bostwick, J

    1990-10-01

    Advances in materials and techniques, especially those involving transposition of muscle and skin flaps, have made breast reconstruction possible for most women who undergo mastectomy for breast cancer. The availability of this option can alleviate the breast and chest wall deformity that results from virtually all local treatment of breast cancer. It is essential that the reconstruction surgeon be part of the breast cancer management team from the beginning of treatment planning and that this surgeon work closely with the general surgeon, medical oncologist, and radiation therapist as well as the adjunctive treatment team members. The patient's clinical status and the type of local treatment will be significant determinants of the reconstructive options. For women with stage I breast cancer, these decisions may be based largely on the oncologist's local and adjunctive therapy procedures and the woman's desire to proceed or delay. For women with systemic disease, all members of the breast management team may need to agree on the advisability and timing of reconstruction. Central to all of the numerous decisions described in this paper regarding the timing, type, and extent of breast reconstruction is the primary goal of the entire team: the best possible management of the breast cancer itself. The promise of attractive, symmetric, and natural appearing breasts, complete with a symmetric nipple-areolar complex, has eased somewhat the diminishment of self-esteem and the threat to femininity that can accompany the loss of a breast. By lowering fear, the widely recognized availability of breast reconstruction may encourage more women to monitor their breasts and seek diagnosis of changes and may influence selection of the type of local treatment if cancer is detected. Because of the psychological and cultural significance of the breast, the reconstructive surgeon must be particularly sensitive to the psychological and aesthetic expectations of the patient. Even in

  3. Chalet. Reconstruction from Memory

    OpenAIRE

    Gheysen, Eva

    2015-01-01

    In the research project several design tactics are developed in order to counteract the phenomenon of experiential erosion. This particular project explored one of the tactics: Reconstruction from Memory. When reconstructing space from memory, isolated spatial fragments from the past are reformed into a new, decontextualized construct that represents the most memorable experiences evoked by that space. These memories give insight in which architectural features strongly affect our experience ...

  4. Cosmic tidal reconstruction

    Science.gov (United States)

    Zhu, Hong-Ming; Pen, Ue-Li; Yu, Yu; Er, Xinzhong; Chen, Xuelei

    2016-05-01

    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 known to be 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 the theoretical framework of 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 ≲0.1 h /Mpc ), with the filter scale ˜1.25 Mpc /h . This is useful in the 21 cm intensity mapping survey, where the long-wavelength radial modes are lost due to a foreground subtraction process.

  5. 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).

  6. 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...

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. Randomization Resilient To Sensitive Reconstruction

    CERN Document Server

    Wang, Ke; Fu, Ada Waichee

    2012-01-01

    With the randomization approach, sensitive data items of records are randomized to protect privacy of individuals while allowing the distribution information to be reconstructed for data analysis. In this paper, we distinguish between reconstruction that has potential privacy risk, called micro reconstruction, and reconstruction that does not, called aggregate reconstruction. We show that the former could disclose sensitive information about a target individual, whereas the latter is more useful for data analysis than for privacy breaches. To limit the privacy risk of micro reconstruction, we propose a privacy definition, called (epsilon,delta)-reconstruction-privacy. Intuitively, this privacy notion requires that micro reconstruction has a large error with a large probability. The promise of this approach is that micro reconstruction is more sensitive to the number of independent trials in the randomization process than aggregate reconstruction is; therefore, reducing the number of independent trials helps a...

  14. 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.

  15. 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.

  16. Experimental Contact Lens to Prevent Glaucoma-Induced Blindness

    Science.gov (United States)

    ... An Experimental Contact Lens to Prevent Glaucoma-Induced Blindness By Sharon Reynolds Posted January 23, 2014 An ... group of conditions that can result in irreversible blindness. This vision loss can be reduced if glaucoma ...

  17. 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.

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

    Science.gov (United States)

    ... Find Services for People Who Are Blind or Visually Impaired Category All Advocacy Assessment/Evaluation Audio, Braille or ... Find Services for People Who Are Blind or Visually Impaired Browse All Search Categories About the Directory Request ...

  19. 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.

  20. 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.

  1. 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…

  2. Usage of Blinds Software in Libraries

    OpenAIRE

    Fatema El Zahraa Mohamed Abdou

    2006-01-01

    The research reviews some of blinds software used in libraries, it reviews the following software : JAWS, Zoomtext, Kurzuail. Then deals the services offered by the software in libraries, these services are : pronouncing the written texts, printing in Brail method, educational software for computer, browsing the internet, and enlarging texts on the screen.

  3. Cognitive Development in Deaf-Blind Children.

    Science.gov (United States)

    Rittenhouse, Robert K.

    The paper reviews the literature and proposes a study on how nonlanguage deaf/blind children (ages 2 to 14) match and classify, the age at which the skills are reached, and the role of language in the process. The theories of J. Piaget and J. Bruner on the importance of language in stage development are explored. The Ss would be matched for age…

  4. CI-TAB: View for the Blind.

    Science.gov (United States)

    Abrams, Ken

    1979-01-01

    The article describes the development and content of a comprehensive career education program for blind elementary and secondary students. Eight areas are explored in the program: job search skills, job behavior, hygiene and grooming, purchase habits, budgeting, banking, home management, and health care. (CL)

  5. 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.

  6. Wavelet coherence analysis of change blindness

    International Nuclear Information System (INIS)

    Change blindness is the incapability of the brain to detect substantial visual changes in the presence of other visual interruption. The objectives of this study are to examine the EEG (Electroencephalographic) based changes in functional connectivity of the brain due to the change blindness. The functional connectivity was estimated using the wavelet-based MSC (Magnitude Square Coherence) function of ERPs (Event Related Potentials). The ERPs of 30 subjects were used and were recorded using the visual attention experiment in which subjects were instructed to detect changes in visual stimulus presented before them through the computer monitor. The two-way ANOVA statistical test revealed significant increase in both gamma and theta band MSCs, and significant decrease in beta band MSC for change detection trials. These findings imply that change blindness might be associated to the lack of functional connectivity in gamma and theta bands and increase of functional connectivity in beta band. Since gamma, theta, and beta frequency bands reflect different functions of cognitive process such as maintenance, encoding, retrieval, and matching and work load of VSTM (Visual Short Term Memory), the change in functional connectivity might be correlated to these cognitive processes during change blindness. (author)

  7. Reconstructed Jets at RHIC

    CERN Document Server

    Salur, Sevil

    2010-01-01

    To precisely measure jets over a large background such as pile up in high luminosity p+p collisions at LHC, a new generation of jet reconstruction algorithms is developed. These algorithms are also applicable to reconstruct jets in the heavy ion environment where large event multiplicities are produced. Energy loss in the medium created in heavy ion collisions are already observed indirectly via inclusive hadron distributions and di-hadron correlations. Jets can be used to study this energy loss in detail with reduced biases. We review the latest results on jet-medium interactions as seen in A+A collisions at RHIC, focusing on the recent progress on jet reconstruction in heavy ion collisions.

  8. 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

    OBJECTIVES: We aimed to assess dream content in groups of congenitally blind (CB), late blind (LB), and age- and sex-matched sighted control (SC) participants. METHODS: We conducted an observational study of 11 CB, 14 LB, and 25 SC participants and collected dream reports over a 4-week period....... 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...

  9. Permutationally invariant state reconstruction

    DEFF Research Database (Denmark)

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

    2012-01-01

    -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...

  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...... of radiation therapy was associated with a non-significantly increased risk of reoperation after both 1-stage (HR = 1.4; 95% CI: 0.7-2.5) and 2-stage (HR = 1.6; 95% CI: 0.9-3.1) procedures. Reconstruction failure was highest (13.2%) in the 2-stage procedures with a history of radiation therapy. Breast...

  11. 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.

  12. 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.)

  13. 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.

  14. Perbandingan Efektivitas Ishihara Colour Blind Test dan Farnsworth Munsell Colour Blind Test di Fakuktas di Fakultas Kedokteran Gigi Universitas Sumatera Utara Tahun 2013

    OpenAIRE

    Indriati, Dwi Meutia

    2015-01-01

    Colour blindness is a disease caused by the inability of cone cells to capture a certain colour spectrum. Colour blindness is generally more contained on the male than the females with a 20:1 ratio. Colour blindness can be diagnosed with several test which Ishihar Colour Blind Test and Farnworth Munsell Colour Blind Test. The purpose of this research was to see a comparison the effectiveness between Ishihara Colour Blind Test with Farmsworth Munsell Colour Blind Test at the Faculty Dentist...

  15. 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…

  16. Restrictive partially blind signature for resource-constrained information systems

    NARCIS (Netherlands)

    Qiu, Weidong; Gong, Zheng; Liu, Bozhong; Long, Yu; Chen, Kefei

    2010-01-01

    Restrictive partially blind signature, which is designed for privacy oriented information systems, allows a user to obtain a blind signature from a signer whilst the blind message must obey some certain rules. In order to reduce storage and communication costs, several public-key cryptosystems are c

  17. What do colour-blind people really see?

    NARCIS (Netherlands)

    Hogervorst, M.A.; Alferdinck, J.W.A.M.

    2008-01-01

    Problem: colour perception of dichromats (colour-blind persons) Background: Various models have been proposed (e. g. Walraven & Alferdinck, 1997; Brettel et al. , 1997) to model reduced colour vision of colour-blind people. It is clear that colour-blind people cannot distinguish certain object colou

  18. Characteristics of Individuals with Congenital and Acquired Deaf-Blindness

    Science.gov (United States)

    Dalby, Dawn M.; Hirdes, John P.; Stolee, Paul; Strong, J. Graham; Poss, Jeff; Tjam, Erin Y.; Bowman, Lindsay; Ashworth, Melody

    2009-01-01

    Using a standardized assessment instrument, the authors compared 182 adults with congenital deaf-blindness and those with acquired deaf-blindness. They found that those with congenital deaf-blindness were more likely to have impairments in cognition, activities of daily living, and social interactions and were less likely to use speech for…

  19. 42 CFR 435.531 - Determinations of blindness.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Determinations of blindness. 435.531 Section 435... ISLANDS, AND AMERICAN SAMOA Categorical Requirements for Eligibility Blindness § 435.531 Determinations of blindness. (a) Except as specified in paragraph (b) of this section, in determining blindness— (1)...

  20. OUR BLIND CHILDREN, GROWING AND LEARNING WITH THEM.

    Science.gov (United States)

    LOWENFELD, BERTHOLD

    WRITTEN AS AN AID TO PARENTS, THIS BOOK PRESENTS FACTS ON BLINDNESS AND PRACTICAL INFORMATION ON THE REARING OF BLIND CHILDREN FROM INFANCY THROUGH ADOLESCENCE. INFORMATION IS GIVEN ABOUT TEACHING BLIND CHILDREN SKILLS AND HABITS RELATED TO EATING, TOILET TRAINING, SLEEPING, DRESSING, WALKING, TALKING, AND PLAYING. SCHOOLING AND RELATED QUESTIONS…

  1. Comparison of Quality of Life and Social Skills between Students with Visual Problems (Blind and Partially Blind) and Normal Students

    OpenAIRE

    Fereshteh Kordestani; Azam Daneshfar; Davood Roustaee

    2014-01-01

    This study aimed to compare the quality of life and social skills between students who are visually impaired (blind and partially blind) and normal students. The population consisted of all students with visual problems (blind and partially blind) and normal students in secondary schools in Tehran in the academic year 2013-2014. Using a multi-stage random sampling method, 40 students were selected from each group. The SF-36s quality of life questionnaire and Foster and Inderbitzen social skil...

  2. 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.

  3. 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.

  4. Breast reconstruction - natural tissue

    Science.gov (United States)

    ... muscle flap; TRAM; Latissimus muscle flap with a breast implant; DIEP flap; DIEAP flap; Gluteal free flap; ... If you are having breast reconstruction at the same time as mastectomy, the surgeon may do either of the following: Skin-sparing mastectomy. This means ...

  5. 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...

  6. 20 CFR 416.981 - Meaning of blindness as defined in the law.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Meaning of blindness as defined in the law... INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Blindness § 416.981 Meaning of blindness as defined in the law. We will consider you blind under the law for payment...

  7. Breast reconstruction: Correlation between different procedures, reconstruction timing and complications

    Directory of Open Access Journals (Sweden)

    Anđelkov Katarina

    2011-01-01

    Full Text Available Introduction. Improved psychophysical condition after breast reconstruction in women has been well documented Objective. To determine the most optimal technique with minimal morbidity, the authors examined their results and complications based on reconstruction timing (immediate and delayed reconstruction and three reconstruction methods: TRAM flap, latissimus dorsi flap and reconstruction with tissue expanders and implants. Methods. Reconstruction was performed in 60 women of mean age 51.1 years. We analyzed risk factors: age, body mass index (BMI, smoking history and radiation therapy in correlation with timing and method of reconstruction. Complications of all three methods of reconstruction were under 1.5-2-year follow-up after the reconstruction. All data were statistically analyzed. Results. Only radiation had significant influence on the occurrence of complications both before and after the reconstruction, while age, smoking and BMI had no considerable influence of the development of complications. There were no statistically significant correlation between the incidence of complications, time and method of reconstruction. Conclusion. Any of the aforementioned breast reconstruction techniques can yield good results and a low rate of re-operations. To choose the best method, the patient needs to be as well informed as possible about the options including the risks and benefits of each method.

  8. 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.

  9. Dual-source CT coronary imaging in heart transplant recipients: image quality and optimal reconstruction interval

    Energy Technology Data Exchange (ETDEWEB)

    Bastarrika, Gorka; Arraiza, Maria; Pueyo, Jesus C. [Clinica Universitaria, Universidad de Navarra, Department of Radiology, Pamplona (Spain); Cecco, Carlo N. de [Universita' di Roma ' ' Sapienza' ' -Ospedale Sant' Andrea, Department of Radiology, Rome (Italy); Ubilla, Matias; Mastrobuoni, Stefano; Rabago, Gregorio [Clinica Universitaria, Universidad de Navarra, Department of Cardiovascular Surgery, Pamplona (Spain)

    2008-09-15

    The image quality and optimal reconstruction interval for coronary arteries in heart transplant recipients undergoing non-invasive dual-source computed tomography (DSCT) coronary angiography was evaluated. Twenty consecutive heart transplant recipients who underwent DSCT coronary angiography were included (19 male, one female; mean age 63.1{+-}10.7 years). Data sets were reconstructed in 5% steps from 30% to 80% of the R-R interval. Two blinded independent observers assessed the image quality of each coronary segments using a five-point scale (from 0 = not evaluative to 4=excellent quality). A total of 289 coronary segments in 20 heart transplant recipients were evaluated. Mean heart rate during the scan was 89.1{+-}10.4 bpm. At the best reconstruction interval, diagnostic image quality (score {>=}2) was obtained in 93.4% of the coronary segments (270/289) with a mean image quality score of 3.04{+-} 0.63. Systolic reconstruction intervals provided better image quality scores than diastolic reconstruction intervals (overall mean quality scores obtained with the systolic and diastolic reconstructions 3.03{+-}1.06 and 2.73{+-}1.11, respectively; P<0.001). Different systolic reconstruction intervals (35%, 40%, 45% of RR interval) did not yield to significant differences in image quality scores for the coronary segments (P=0.74). Reconstructions obtained at the systolic phase of the cardiac cycle allowed excellent diagnostic image quality coronary angiograms in heart transplant recipients undergoing DSCT coronary angiography. (orig.)

  10. 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.

  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. 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.

  13. Blind Estimation of Multiple Carrier Frequency Offsets

    CERN Document Server

    Yu, Yuanning; Poor, H Vincent; Koivunen, Visa

    2007-01-01

    Multiple carrier-frequency offsets (CFO) arise in a distributed antenna system, where data are transmitted simultaneously from multiple antennas. In such systems the received signal contains multiple CFOs due to mismatch between the local oscillators of transmitters and receiver. This results in a time-varying rotation of the data constellation, which needs to be compensated for at the receiver before symbol recovery. This paper proposes a new approach for blind CFO estimation and symbol recovery. The received base-band signal is over-sampled, and its polyphase components are used to formulate a virtual Multiple-Input Multiple-Output (MIMO) problem. By applying blind MIMO system estimation techniques, the system response is estimated and used to subsequently transform the multiple CFOs estimation problem into many independent single CFO estimation problems. Furthermore, an initial estimate of the CFO is obtained from the phase of the MIMO system response. The Cramer-Rao Lower bound is also derived, and the la...

  14. 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.

  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. 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.

  17. Permanent Cortical Blindness After Bronchial Artery Embolization

    International Nuclear Information System (INIS)

    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

  18. 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

  19. Making Visual Maps Accessible to the Blind

    OpenAIRE

    Buzzi, Maria Claudia; Buzzi, Marina; Leporini, Barbara; Martusciello, Loredana

    2011-01-01

    Visual maps deliver content in a simple and effective way. They can be useful for various purposes in areas such as street guidance, surrounding information, and education. However, sightless persons are unable to explore visual maps and risk being cut off from several multimedia Web applications. In this paper, starting from accessibility issues of map-based applications, we discuss possible interaction modalities and devices to use for truly achieving usage perspectives desired by blind peo...

  20. 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.

  1. Social Sciences for the Prevention of Blindness

    OpenAIRE

    Goldschmidt, Pablo

    2015-01-01

    Organizations working for the elimination of Chlamydia-triggered blindness (trachoma) follow the WHO SAFE strategy (surgery for trichiasis, antibiotics, face washing and environmental changes) with the aim to achieve a minimum of 80% of children with clean faces in endemic communities, mass treatment covering the whole district with trachoma rates of 10% or more and surveillance plans. Trachoma recurrence that is common after implementing the SAFE strategy 3, 5 or even 7 times evidence that t...

  2. Blind surveys for radio pulsars and transients

    OpenAIRE

    Lorimer, D.R.

    2010-01-01

    The main reasons for searching for pulsars are to: (i) get an accurate census of the neutron star population and its origin and evolution; (ii) connect neutron stars to other stellar populations in the Galaxy and globular clusters; (iii) study Galactic astronomy (the interstellar medium and magnetic field); (iv) find and study new interesting individual objects; (v) study pulsar phenomenology; (vi) find pulsars to add to the sensitivity of pulsar timing arrays. This review focuses on blind (i...

  3. Broadband Venetian Blind polarizer with dual vanes

    Science.gov (United States)

    Conroy, Bruce L.; Hoppe, Daniel J.; Imbriale, William A.

    1993-05-01

    During development of a Venetian Blind polarizer, high reflections and substantial pattern deformation were noted. Analysis showed that when the polarizer was illuminated slightly off axis, a degenerate mode was excited. This mode is resonant at the design center frequency, and was the cause of the problems. A design developed using dual vanes has been shown to be free of the problem. It also has greater bandwidth.

  4. Blind Source Separation: the Sparsity Revolution

    OpenAIRE

    Bobin, J.; Starck, Jean-Luc; Moudden, Y.; Fadili, Jalal M.

    2008-01-01

    Over the last few years, the development of multi-channel sensors motivated interest in methods for the coherent processing of multivariate data. Some specific issues have already been addressed as testified by the wide literature on the so-called blind source separation (BSS) problem. In this context, as clearly emphasized by previous work, it is fundamental that the sources to be retrieved present some quantitatively measurable diversity. Recently, sparsity and morphological diversity have ...

  5. 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.

  6. Change blindness: eradication of gestalt strategies

    OpenAIRE

    Wilson, Steve; Goddard, Paul

    2011-01-01

    Arrays of eight, texture-defined rectangles were used as stimuli in a one-shot change blindness (CB) task where there was a 50% chance that one rectangle would change orientation between two successive presentations separated by an interval. CB was eliminated by cueing the target rectangle in the first stimulus, reduced by cueing in the interval and unaffected by cueing in the second presentation. This supports the idea that a representation was formed that persisted through the interval befo...

  7. A Completely Blind Video Integrity Oracle.

    Science.gov (United States)

    Mittal, Anish; Saad, Michele A; Bovik, Alan C

    2016-01-01

    Considerable progress has been made toward developing still picture perceptual quality analyzers that do not require any reference picture and that are not trained on human opinion scores of distorted images. However, there do not yet exist any such completely blind video quality assessment (VQA) models. Here, we attempt to bridge this gap by developing a new VQA model called the video intrinsic integrity and distortion evaluation oracle (VIIDEO). The new model does not require the use of any additional information other than the video being quality evaluated. VIIDEO embodies models of intrinsic statistical regularities that are observed in natural vidoes, which are used to quantify disturbances introduced due to distortions. An algorithm derived from the VIIDEO model is thereby able to predict the quality of distorted videos without any external knowledge about the pristine source, anticipated distortions, or human judgments of video quality. Even with such a paucity of information, we are able to show that the VIIDEO algorithm performs much better than the legacy full reference quality measure MSE on the LIVE VQA database and delivers performance comparable with a leading human judgment trained blind VQA model. We believe that the VIIDEO algorithm is a significant step toward making real-time monitoring of completely blind video quality possible. PMID:26599970

  8. Corona solar blind ultraviolet image detecting method

    Science.gov (United States)

    Yin, Li-min; Tang, Wen-qing; Zhang, Yu

    2009-07-01

    Corona is one of important reasons of electrical energy loss in the electric power. According to incomplete statistics, corona loss electrical energy has achieved two thousands and fifty millions kW.h in our nation every year. Sometimes corona also can have some disturbance to radio and communication. Therefore to discover and examine corona promptly has the extremely vital significance for conserving energy and realizing high quality communication. Ultraviolet image detecting technology is a preferred corona detection method in electric power. It may realize all-weather reliable survey to corona. The solar blind ultraviolet signal discharged by corona is quite weak. Moreover the ultraviolet image quality has been affected seriously by the detection system noise. A corona solar blind ultraviolet image processing method is proposed in this paper. Ultraviolet image has so small target, low contrast image, district characteristic and real-time demand that it is processed by multi-scale ultraviolet morphology filter technology based on mathematics morphology in this paper. Results show that the method can stretch image contrast, enhance target and weaken noise. The algorithm is easy to deal in parallel and it can be realized easily by hardware. It will be accurately demarcated when the condition of device need to be absolutely measured. The paper proposes a kind of mathematics morphology algorithm. Solar blind ultraviolet image will be further processed according to temperature and humidity in order to remove the infection of corona discharge demarcation and solve correct demarcation question when equipment condition need to be absolutely measured.

  9. Direct costs of blindness in Australia.

    Science.gov (United States)

    Wright, S E; Keeffe, J E; Thies, L S

    2000-06-01

    This study calculated the direct financial costs of blindness to the Australian government and community. Three case studies, representative of Australians with severely impaired vision, were used to calculate the annual costs associated with blindness. The costs include pensions, subsidies, concessions, equipment and services. Case I was a retired person with age-related macular degeneration, case 2 a working aged person with diabetic retinopathy, and case 3 a school student with congenital vision impairment. Sensitivity analysis was used to show the possible range of costs for each case. For case I, direct cost was $ 14686 with a range from $9749 to $22507. The cost for case 2 was $17701 ranging from $9669 to $26720. Costs associated with care and education of case 3 were $15948 ranging from $5106 to $23798. In addition to the social costs to a person who is blind, there are significant financial costs to the government and the community that will increase substantially with the ageing of the Australian population. PMID:10981781

  10. Hypersensitivity to pain in congenital blindness.

    Science.gov (United States)

    Slimani, Hocine; Danti, Sabrina; Ricciardi, Emiliano; Pietrini, Pietro; Ptito, Maurice; Kupers, Ron

    2013-10-01

    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, congenitally blind subjects have lower heat pain thresholds, rate suprathreshold heat pain stimuli as more painful, and have increased sensitivity for cold pain stimuli. Thresholds for nonpainful thermal stimulation did not differ between groups. The results of the pain questionnaires further indicated that blind subjects are more attentive to signals of external threats. These findings indicate that the absence of vision from birth induces a hypersensitivity to painful stimuli, lending new support to a model of sensory integration of vision and pain processing. PMID:24040972

  11. 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.

  12. 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

  13. 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...

  14. 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.

  15. Reconstructing holographic quintessence

    OpenAIRE

    Zhang, Xin

    2006-01-01

    The holographic dark energy model is an attempt for probing the nature of dark energy within the framework of quantum gravity. The dimensionless parameter $c$ determines the main property of the holographic dark energy. With the choice of $c\\geq 1$, the holographic dark energy can be described completely by a quintessence scalar field. In this paper, we show this quintessential description of the holographic dark energy with $c\\geq 1$ and reconstruct the potential of the quintessence as well ...

  16. LOFAR sparse image reconstruction

    Science.gov (United States)

    Garsden, H.; Girard, J. N.; Starck, J. L.; Corbel, S.; Tasse, C.; Woiselle, A.; McKean, J. P.; van Amesfoort, A. S.; Anderson, J.; Avruch, I. M.; Beck, R.; Bentum, M. J.; Best, P.; Breitling, F.; Broderick, J.; Brüggen, M.; Butcher, H. R.; Ciardi, B.; de Gasperin, F.; de Geus, E.; de Vos, M.; Duscha, S.; Eislöffel, J.; Engels, D.; Falcke, H.; Fallows, R. A.; Fender, R.; Ferrari, C.; Frieswijk, W.; Garrett, M. A.; Grießmeier, J.; Gunst, A. W.; Hassall, T. E.; Heald, G.; Hoeft, M.; Hörandel, J.; van der Horst, A.; Juette, E.; Karastergiou, A.; Kondratiev, V. I.; Kramer, M.; Kuniyoshi, M.; Kuper, G.; Mann, G.; Markoff, S.; McFadden, R.; McKay-Bukowski, D.; Mulcahy, D. D.; Munk, H.; Norden, M. J.; Orru, E.; Paas, H.; Pandey-Pommier, M.; Pandey, V. N.; Pietka, G.; Pizzo, R.; Polatidis, A. G.; Renting, A.; Röttgering, H.; Rowlinson, A.; Schwarz, D.; Sluman, J.; Smirnov, O.; Stappers, B. W.; Steinmetz, M.; Stewart, A.; Swinbank, J.; Tagger, M.; Tang, Y.; Tasse, C.; Thoudam, S.; Toribio, C.; Vermeulen, R.; Vocks, C.; van Weeren, R. J.; Wijnholds, S. J.; Wise, M. W.; Wucknitz, O.; Yatawatta, S.; Zarka, P.; Zensus, A.

    2015-03-01

    Context. The LOw Frequency ARray (LOFAR) radio telescope is a giant digital phased array interferometer with multiple antennas distributed in Europe. It provides discrete sets of Fourier components of the sky brightness. Recovering the original brightness distribution with aperture synthesis forms an inverse problem that can be solved by various deconvolution and minimization methods. Aims: Recent papers have established a clear link between the discrete nature of radio interferometry measurement and the "compressed sensing" (CS) theory, which supports sparse reconstruction methods to form an image from the measured visibilities. Empowered by proximal theory, CS offers a sound framework for efficient global minimization and sparse data representation using fast algorithms. Combined with instrumental direction-dependent effects (DDE) in the scope of a real instrument, we developed and validated a new method based on this framework. Methods: We implemented a sparse reconstruction method in the standard LOFAR imaging tool and compared the photometric and resolution performance of this new imager with that of CLEAN-based methods (CLEAN and MS-CLEAN) with simulated and real LOFAR data. Results: We show that i) sparse reconstruction performs as well as CLEAN in recovering the flux of point sources; ii) performs much better on extended objects (the root mean square error is reduced by a factor of up to 10); and iii) provides a solution with an effective angular resolution 2-3 times better than the CLEAN images. Conclusions: Sparse recovery gives a correct photometry on high dynamic and wide-field images and improved realistic structures of extended sources (of simulated and real LOFAR datasets). This sparse reconstruction method is compatible with modern interferometric imagers that handle DDE corrections (A- and W-projections) required for current and future instruments such as LOFAR and SKA.

  17. Orthotopic neobladder reconstruction

    OpenAIRE

    Chang, Dwayne T. S.; Nathan Lawrentschuk

    2015-01-01

    Orthotopic neobladder reconstruction is becoming an increasingly common urinary diversion following cystectomy for bladder cancer. This is in recognition of the potential benefits of neobladder surgery over creation of an ileal conduit related to quality of life (QoL), such as avoiding the need to form a stoma with its cosmetic, psychological and other potential complications. The PubMed database was searched using relevant search terms for articles published electronically between January 19...

  18. The art of reconstruction

    OpenAIRE

    Healey, Michael; Esson, Michael

    2011-01-01

    The ‘Art of Reconstruction Research Project’ is where re-skilling of plastic surgeons by artists is already in an embryonic phase. In integrating the required network of associated skills, expertise and experience, the research collaboration brings together artists within The Drawing Research Group of The Faculty of Art, Architecture and Design (AAD) and the distinguished work of Professor Mike Esson, Director, The International Drawing Research Institute (IDRI). Th...

  19. 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.

  20. 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. PMID:23307219

  1. 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

  2. Reconstruction of the perineum.

    Science.gov (United States)

    Wong, David Sau-Yan

    2014-09-01

    The pelvic and perineal regions are affected by a heterogeneous spectrum of pathologies, many with a tendency to recur. Extensive mutilation carries physical, sexual, and psychological sequelae. Primary reconstruction reduces morbidity and shortens recovery. Modern management calls for a multidisciplinary approach. Not uncommonly, patients come with previous surgery and/or chemoirradiation. They may also be elderly and debilitated. The literature on reconstruction of the perineum can be confusing because knowledge has evolved by an accumulation of isolated short reports of individual methods. This led to the lack of a unifying basis for nomenclature and a failure to relate specific techniques to their roles in repairing particular types of defects. This article gives an overall summary of the approaches in a structured and rational manner. Defects of the external pelvis and perineal lining are usually amenable to coverage with local or regional fasciocutaneous flaps, if primary closure or skin graft is not appropriate. These flaps depend on the integrity of the vascular territories of the internal pudendal, the upper medial thigh plexus, or the descending branches of the inferior gluteal. The location and extent of the resection usually determine the requirements of the reconstruction and may dictate the choice of options. When defects are pelviperineal, particularly when the vagina needs to be reconstructed, myocutaneous flaps are of proven advantage in dealing with both the resurfacing as well as providing the bulk needed to fill the pelvic cavity after extensive resections. The rectus, gluteus, and gracilis are the best known options. Owing to the intrinsic limitations with the gracilis flap, the rectus and gluteus flaps have largely superseded its role in most situations. The rectus flap, in particular, provides good bulk as well as reliable skin. The use of muscle sparing flaps based on the perforator principle in suitable instances has increasingly been

  3. 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.

  4. Untraceable partially blind signature based on DLOG problem.

    Science.gov (United States)

    Huang, Zheng; Chen, Ke-fei; Kou, Wei-dong

    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. PMID:14663850

  5. A New Proxy Blind Signature Scheme based on ECDLP

    Directory of Open Access Journals (Sweden)

    Daniyal M Alghazzawi

    2011-05-01

    Full Text Available A proxy blind signature scheme is a special form of blind signature which allows a designated person called proxy signer to sign on behalf of two or more original signers without knowing the content of the message or document. It combines the advantages of proxy signature, blind signature and multi-signature scheme and satisfies the security properties of both proxy and blind signature scheme. Most of the exiting proxy blind signature schemes were developed based on the mathematical hard problems integer factorization (IFP and simple discrete logarithm (DLP which take sub-exponential time to solve. This paper describes an secure simple proxy blind signature scheme based on Elliptic Curve Discrete Logarithm Problem (ECDLP takes fully-exponential time. This can be implemented in low power and small processor mobile devices such as smart card, PDA etc. Here also we describes implementation issues of various scalar multiplication for ECDLP.

  6. 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.

  7. Untraceable partially blind signature based on DLOG problem

    Institute of Scientific and Technical Information of China (English)

    HUANG Zheng(黄征); CHEN Ke-fei(陈克非); KOU Wei-dong(寇卫东)

    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.

  8. 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....

  9. 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.

  10. Causes of childhood blindness in the northeastern states of India

    OpenAIRE

    Bhattacharjee Harsha; Das Kalyan; Borah Rishi; Guha Kamalesh; Gogate Parikshit; Purukayastha S; Gilbert Clare

    2008-01-01

    Background: The northeastern region (NER) of India is geographically isolated and ethno-culturally different from the rest of the country. There is lacuna regarding the data on causes of blindness and severe visual impairment in children from this region. Aim: To determine the causes of severe visual impairment and blindness amongst children from schools for the blind in the four states of NER of India. Design and Setting: Survey of children attending special education schools for the b...

  11. Evaluation of children in six blind schools of Andhra Pradesh

    OpenAIRE

    Hornby Stella; Adolph Shajan; Gothwal Vijaya; Gilbert Clare; Dandona Lalit; Foster Allen

    2000-01-01

    Purpose: 1.To determine the anatomical site and underlying causes of severe visual impairment and blindness in children in special education in Andhra Pradesh, India. 2. To compare the causes of blindness in two different regions in the state. 3. To evaluate improvement with correction of refractive error and low-vision devices (LVDs) Methods: Children in 6 schools for the blind and in 3 integrated education programmes were examined by one ophthalmologist, and were refracted and assessed for ...

  12. 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.

  13. "Visual" Cortex Responds to Spoken Language in Blind Children

    OpenAIRE

    Bedny, Marina; Richardson, Hilary; Saxe, Rebecca R.

    2015-01-01

    Plasticity in the visual cortex of blind individuals provides a rare window into the mechanisms of cortical specialization. In the absence of visual input, occipital (“visual”) brain regions respond to sound and spoken language. Here, we examined the time course and developmental mechanism of this plasticity in blind children. Nineteen blind and 40 sighted children and adolescents (4–17 years old) listened to stories and two auditory control conditions (unfamiliar foreign speech, and music). ...

  14. 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.

  15. Physics Education for Blind Students: The Teachers' Perspective

    Science.gov (United States)

    Ferreira, Amauri; Dickman, Adriana

    2008-03-01

    We discuss the challenge high school teachers face when teaching physics to the blind. Using the oral history method, we interview physics teachers who have dealt with the inclusion of blind students in regular classrooms. Based on our study, we find that the performance of these students varies, depending on the studied subject. The narrative makes clear the teachers' lack of preparation to deal with inclusion, and their search for alternative methods to improve blind students' learning.

  16. 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...

  17. Blind SNR estimation for limited time series

    Energy Technology Data Exchange (ETDEWEB)

    Tekbas, Onder Haluk [Department of Technical Sciences, Turkish Military Academy, 06654 Bakanliklar, Ankara (Turkey)]. E-mail: ohtekbas@kho.edu.tr

    2007-08-15

    A blind SNR estimation method for discrete data is presented. The original noise-free data is assumed to follow a known signal model with an unknown attenuation. The SNR in noisy data is estimated using a polynomial fit obtained from the correlative characteristics between SNR and variance fractal dimension values. The bias and the 'standard error' (root mean square error) of the estimator are used as performance measures. The simulated performance of the estimator for a specific signal model with real additive white Gaussian noise assumption is compared to that of a published decision-aided (nonblind) SNR estimator.

  18. 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.

  19. 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.

  20. 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.

  1. 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…

  2. 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.

  3. 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.

  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. Non-microsurgical breast reconstruction

    Directory of Open Access Journals (Sweden)

    Sharma Sheel

    2007-12-01

    Full Text Available Breast reconstruction after mastectomy should aim at resulting in an aesthetic outcome that matches the patient′s expectations and without interfering in the oncologic treatment. Whether the reconstruction is performed immediately or in a delayed fashion depends on various factors, which needs detailed attention. Autologous tissue, implants or both are used in the reconstruction. This article reviews the current concepts in these, with emphasis on non-microsurgical methods of using the autologous tissue for reconstruction. Breast conservation has become an accepted practice of treatment. Reconstruction in these situations as well as in an occasion when the surgery is done for failed breast conservation is discussed in detail. The article also reviews the various methods for nipple reconstruction available.

  6. 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...

  7. 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.

  8. 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...

  9. 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.

  10. Reconstruction of symmetric Potts Models

    OpenAIRE

    Sly, Allan

    2008-01-01

    The reconstruction problem on the tree has been studied in numerous contexts including statistical physics, information theory and computational biology. However, rigorous reconstruction thresholds have only been established in a small number of models. We prove the first exact reconstruction threshold in a non-binary model establishing the Kesten-Stigum bound for the 3-state Potts model on regular trees of large degree. We further establish that the Kesten-Stigum bound is not tight for the $...

  11. 20 CFR 416.933 - How we make a finding of presumptive disability or presumptive blindness.

    Science.gov (United States)

    2010-04-01

    ... disability or presumptive blindness. 416.933 Section 416.933 Employees' Benefits SOCIAL SECURITY... Blindness Presumptive Disability and Blindness § 416.933 How we make a finding of presumptive disability or presumptive blindness. We may make a finding of presumptive disability or presumptive blindness if...

  12. 20 CFR 416.931 - The meaning of presumptive disability or presumptive blindness.

    Science.gov (United States)

    2010-04-01

    ... presumptive blindness. 416.931 Section 416.931 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Presumptive Disability and Blindness § 416.931 The meaning of presumptive disability or presumptive blindness. If you...

  13. 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.

  14. 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.

  15. 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.

  16. An investigation of the Venetian blind effect.

    Science.gov (United States)

    Filley, E T; Khutoryansky, Natalie; Dobias, J J; Stine, Wm Wren

    2011-01-01

    When a rectangular wave grating is binocularly viewed with a neutral density filter over one eye, an illusory rotation resembling that of a partially opened Venetian blind is perceived (Cibis and Haber, 1951). Using a binary classification task, in the first experiment, the probability of perceiving a rotation in a given direction was measured as a function of a factorial combination of inter-ocular contrast (see Note 1) and luminance ratios. The probability of a rotation in a given direction decreased monotonically with the luminance of the brighter bars when the grating contains a less than unity contrast. This result is inconsistent with (i) the model of the Venetian blind effect proposed by Cibis and Haber (1951), (ii) a mechanism based on irradiation with a compressive non-linearity (von Helmholtz, 1911/1924, pp. 186-193) and (iii) contemporary stereo-energy/cross-correlation models of stereopsis. In the second and third experiments, we tested the prediction that irradiation combined with an early compressive non-linearity in response implies a positive relationship between both the threshold contrast or average luminance disparity to perceive rotation and the magnitude of perceived rotation, and the blur width at the bar's edge. No support was found for the prediction. We propose an intensity difference model of the probability of perceiving a rotation in a given direction as a function of the interocular difference in luminance or contrast. PMID:21864465

  17. Mobility aid for blind figure skaters

    International Nuclear Information System (INIS)

    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

  18. 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.

  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. 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.

  1. Do "mudsplashes" induce tactile change blindness?

    Science.gov (United States)

    Gallace, Alberto; Tan, Hong Z; Spence, Charles

    2007-05-01

    The phenomenon of change blindness (the surprising inability of people to correctly perceive changes between consecutively presented displays), primarily reported in vision, has recently been shown to occur for positional changes presented in tactile displays as well. Here, we studied people's ability to detect changes in the number of tactile stimuli in successively presented displays composed of one to three stimuli distributed over the body surface. In Experiment 1, a tactile mask consisting of the simultaneous activation of all seven possible tactile stimulators was sometimes presented between the two to-be-discriminated tactile displays. In Experiment 2, a "mudsplash" paradigm was used, with a brief irrelevant tactile distractor presented at the moment of change of the tactile display. Change blindness was demonstrated in both experiments, thus showing that the failure to detect tactile change is not necessarily related to (1) the physical disruption between consecutive events, (2) the effect of masking covering the location of the change, or (3) the erasure or resetting of the information contained within an internal representation of the tactile display. These results are interpreted in terms of a limitation in the number of spatial locations/events that can be consciously accessed at any one time. This limitation appears to constrain change-detection performance, no matter the sensory modality in which the stimuli are presented. PMID:17727101

  2. 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.

  3. Unfavourable results in thumb reconstruction

    Directory of Open Access Journals (Sweden)

    Samir M Kumta

    2013-01-01

    Full Text Available The history of thumb reconstruction parallels the history of hand surgery. The attributes that make the thumb unique, and that the reconstructive surgeon must assess and try to restore when reconstructing a thumb, are: Position, stability, strength, length, motion, sensibility and appearance. Deficiency in any of these attributes can reduce the utility of the reconstructed thumb. A detailed assessment of the patient and his requirements needs to be performed before embarking on a thumb reconstruction. Most unsatisfactory results can be attributed to wrong choice of procedure. Component defects of the thumb are commonly treated by tissue from adjacent fingers, hand or forearm. With refinements in microsurgery, the foot has become a major source of tissue for component replacement in the thumb. Bone lengthening, osteoplastic reconstruction, pollicisation, and toe to hand transfers are the commonest methods of thumb reconstruction. Unfavourable results can be classified as functional and aesthetic. Some are common to all types of procedures. However each type of reconstruction has its own unique set of problems. Meticulous planning and execution is essential to give an aesthetic and functionally useful thumb. Secondary surgeries like tendon transfers, bone grafting, debulking, arthrodesis, may be required to correct deficiencies in the reconstruction. Attention needs to be paid to the donor site as well.

  4. 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.

  5. Set Reconstruction on the Hypercube

    OpenAIRE

    Pebody, Luke

    2016-01-01

    Given an action of a group $G$ on a set $S$, the $k$-deck of a subset $T$ of $S$ is the multiset of all subsets of $T$ of size $k$, each given up to translation by $G$. For a given subset $T$, the {\\em reconstruction number} of $T$ is the minimum $k$ such that the $k$-deck uniquely identifies $T$ up to translation by $G$, and the {\\em reconstruction number} of the action $G:S$ is the maximum reconstruction number of any subset of $S$. The concept of reconstruction number extends naturally to ...

  6. 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.

  7. 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...

  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. 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...

  10. The Institute for Deaf-Blind Studies: Proceedings.

    Science.gov (United States)

    Scheffler, Joye A.; And Others

    The document contains 16 papers from the Institute for Deaf Blind Studies, a program to bring together many disciplines and to place emphasis on every aspect of the learning and teaching activity involved in the development of deaf-blind children. The following titles and authors are included: "Current Status of the Rubella Problem" (P. Ziring);…

  11. 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 the...

  12. 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…

  13. About a case of blindness following scorpion envenomation

    Directory of Open Access Journals (Sweden)

    K Delma

    2012-01-01

    Full Text Available The author reports a case of blindness occurred after three scorpion stings in a young woman from the region Ouargla, Algeria. The absence of signs of neurological and cardiovascular envenomation and the functional examinations of eyes is likely to be the consequence of a toxic neuropathy. Two months later, blindness persists and functional prognosis remains reserved.

  14. 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…

  15. Attenuation of Change Blindness in Children with Autism Spectrum Disorders

    Science.gov (United States)

    Fletcher-Watson, Sue; Leekam, Susan R.; Connolly, Brenda; Collis, Jess M.; Findlay, John M.; McConachie, Helen; Rodgers, Jacqui

    2012-01-01

    Change blindness refers to the difficulty most people find in detecting a difference between two pictures when these are presented successively, with a brief interruption between. Attention at the site of the change is required for detection. A number of studies have investigated change blindness in adults and children with autism spectrum…

  16. 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.

  17. 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.

  18. 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,…

  19. 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...

  20. 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…

  1. Double-blind ureteral duplication: report of two cases

    International Nuclear Information System (INIS)

    Blind ending of ureteral duplication is one of the most rare anomalies of the upper urinary tract. We report two cases of ureteral duplication with a blind ending both superiorly and inferiorly, and with no definite communication with the urinary tract. (orig.)

  2. Special samples for investigation into kinetics of blind fatigue cracks

    International Nuclear Information System (INIS)

    Samples designed for investigation into kinetics of elliptic and semi-elliptic fatigue cracks in construction large-size elements and for evaluation of structural material resistance to fracture are developed. Data on form changing of blind fatigue cracks in vessel steel 15KH2MFA are obtained; it is shown, that material anisotropy and load kind affect essentially blind fatigue crack forms

  3. Reconstructing the Alcatraz escape

    Science.gov (United States)

    Baart, F.; Hoes, O.; Hut, R.; Donchyts, G.; van Leeuwen, E.

    2014-12-01

    In the night of June 12, 1962 three inmates used a raft made of raincoatsto escaped the ultimate maximum security prison island Alcatraz in SanFrancisco, United States. History is unclear about what happened tothe escapees. At what time did they step into the water, did theysurvive, if so, where did they reach land? The fate of the escapees has been the subject of much debate: did theymake landfall on Angel Island, or did the current sweep them out ofthe bay and into the cold pacific ocean? In this presentation, we try to shed light on this historic case using avisualization of a high-resolution hydrodynamic simulation of the San Francisco Bay, combined with historical tidal records. By reconstructing the hydrodynamic conditions and using a particle based simulation of the escapees we show possible scenarios. The interactive model is visualized using both a 3D photorealistic and web based visualization. The "Escape from Alcatraz" scenario demonstrates the capabilities of the 3Di platform. This platform is normally used for overland flooding (1D/2D). The model engine uses a quad tree structure, resulting in an order of magnitude speedup. The subgrid approach takes detailed bathymetry information into account. The inter-model variability is tested by comparing the results with the DFlow Flexible Mesh (DFlowFM) San Francisco Bay model. Interactivity is implemented by converting the models from static programs to interactive libraries, adhering to the Basic ModelInterface (BMI). Interactive models are more suitable for answeringexploratory research questions such as this reconstruction effort. Although these hydrodynamic simulations only provide circumstantialevidence for solving the mystery of what happened during the foggy darknight of June 12, 1962, it can be used as a guidance and provides aninteresting testcase to apply interactive modelling.

  4. Gender Mainstreaming and Sustainable Post Disaster Reconstruction,

    OpenAIRE

    Yumarni, Tri; Amaratunga, Dilanthi; Haigh, Richard

    2013-01-01

    Gender inequalities are barriers to achieve sustainable post disaster reconstruction. Mainstreaming gender equality within post disaster reconstruction process can enhance sustainability of reconstruction. Based on a detailed literature review on post disaster reconstruction, this paper identifies pre-requisite conditions for mainstreaming gender within sustainable post disaster reconstruction as ; awareness of gender needs and concerns, a strong gender policy framework, women ...

  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. Markov Random Field Surface Reconstruction

    DEFF Research Database (Denmark)

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

    2010-01-01

    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...

  7. 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.

  8. 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.

  9. The countermeasures against the blinding attack in quantum key distribution

    Science.gov (United States)

    Wang, Jindong; Wang, Hong; Qin, Xiaojuan; Wei, Zhengjun; Zhang, Zhiming

    2016-01-01

    It has been shown that the single photon detectors (SPDs) based on the avalanche photodiode (APD) can be blinded and controlled by the bright light and short trigger pulses. Eavesdropper can get the full information without causing additional quantum bit error rate. Hence, in order to guarantee the security of the quantum key distribution (QKD) systems, some countermeasures, by changing the characteristic of the SPD or monitoring the parameters of the detector, are presented by some research groups. In this paper, we provide a new and effective countermeasure against the blinding attack based on improving the optical scheme of the decoding unit in the QKD system rather than only considering the characteristic of the SPD. In our proposal we use a coupler with asymmetric splitting ratio to distinguish the detection characteristic of the SPD with blinding attack from that without blinding attack. The detailed analysis shows that the proposed scheme is feasible to defense the blinding attack.

  10. Blind separation of sound sources from the principle of least spatial entropy

    Science.gov (United States)

    Dong, Bin; Antoni, Jérôme; Zhang, Erliang

    2014-04-01

    The aim of the paper is to offer a method for separating incoherent and compact sound sources which may overlap in both the space and frequency domains. This is found of interest in acoustical applications involving the identification and ranking of sound sources stemming from different physical origins. The principle proceeds in two steps, the first one being reminiscent to source reconstruction (e.g. as in near-field acoustical holography) and the second one to blind source separation. Specifically, the source mixture is first expanded into a linear combination of spatial basis functions whose coefficients are set by backpropagating the pressures measured by an array of microphones to the source domain. This leads to a formulation similar, but no identical, to blind source separation. In the second step, these coefficients are blindly separated into uncorrelated latent variables, assigned to incoherent "virtual sources". These are shown to be defined up to an arbitrary rotation. A unique set of sound sources is finally recovered by searching for that rotation (by conjugate gradient descent in the Stiefel manifold of unitary matrices) which maximizes their spatial compactness, as measured either by their spatial variance or their spatial entropy. This results in the proposal of two separation criteria coined "least spatial variance" and "least spatial entropy", respectively. The same concept of spatial entropy, which is central to the paper, is also exploited in defining a new criterion, the entropic L-curve, dedicated to determining the number of active sound sources. The idea consists in considering the number of sources that achieves the best compromise between a low spatial entropy (as expected from compact sources) and a low statistical entropy (as expected from a low residual error). The proposed methodology is validated on both laboratory experiments and numerical data, and illustrated on an industrial example concerned with the ranking of sound sources on

  11. 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.

  12. Indoor inertial waypoint navigation for the blind.

    Science.gov (United States)

    Riehle, Timothy H; Anderson, Shane M; Lichter, Patrick A; Whalen, William E; Giudice, Nicholas A

    2013-01-01

    Indoor navigation technology is needed to support seamless mobility for the visually impaired. This paper describes the construction and evaluation of an inertial dead reckoning navigation system that provides real-time auditory guidance along mapped routes. Inertial dead reckoning is a navigation technique coupling step counting together with heading estimation to compute changes in position at each step. The research described here outlines the development and evaluation of a novel navigation system that utilizes information from the mapped route to limit the problematic error accumulation inherent in traditional dead reckoning approaches. The prototype system consists of a wireless inertial sensor unit, placed at the users' hip, which streams readings to a smartphone processing a navigation algorithm. Pilot human trials were conducted assessing system efficacy by studying route-following performance with blind and sighted subjects using the navigation system with real-time guidance, versus offline verbal directions. PMID:24110904

  13. Blind identification of cellular phone cameras

    Science.gov (United States)

    Çeliktutan, Oya; Avcibas, Ismail; Sankur, Bülent

    2007-02-01

    In this paper, we focus on blind source cell-phone identification problem. It is known various artifacts in the image processing pipeline, such as pixel defects or unevenness of the responses in the CCD sensor, black current noise, proprietary interpolation algorithms involved in color filter array [CFA] leave telltale footprints. These artifacts, although often imperceptible, are statistically stable and can be considered as a signature of the camera type or even of the individual device. For this purpose, we explore a set of forensic features, such as binary similarity measures, image quality measures and higher order wavelet statistics in conjunction SVM classifier to identify the originating cell-phone type. We provide identification results among 9 different brand cell-phone cameras. In addition to our initial results, we applied a set of geometrical operations to original images in order to investigate how much our proposed method is robust under these manipulations.

  14. 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...

  15. Double blind placebo controlled exposure to molds

    DEFF Research Database (Denmark)

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

    2005-01-01

    The objective was to develop an experimental setup for human exposure to mold spores, and to study the clinical effect of this exposure in sensitive subjects who had previously experienced potentially building-related symptoms (BRS) at work. From three water-damaged schools eight employees....... 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...

  16. 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

  17. 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

  18. Evidence-Based ACL Reconstruction.

    Science.gov (United States)

    Rodriguez-Merchan, E Carlos

    2015-01-01

    There is controversy in the literature regarding a number of topics related to anterior cruciate ligament (ACL) reconstruction. The purpose of this article is to answer the following questions: 1) Bone-patellar tendon-bone reconstruction (BPTB-R) or hamstrimg reconstruction (H-R); 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-analyses focused 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. PMID:25692162

  19. Children Who Are Deaf-Blind. Practice Perspectives--Highlighting Information on Deaf-Blindness. Number 2

    Science.gov (United States)

    Malloy, Peggy; Killoran, John

    2007-01-01

    Although the term deaf-blind implies a complete absence of hearing and sight, in reality, it refers to children with varying degrees of vision and hearing losses. The type and severity differ from child to child. The key feature of deaf-blindness is that the combination of losses limits access to auditory and visual information. Children with…

  20. College Students Who Are Deaf-Blind. Practice Perspectives--Highlighting Information on Deaf-Blindness. Number 7

    Science.gov (United States)

    Arndt, Katrina

    2011-01-01

    Imagine being in college and being deaf-blind. What opportunities might you have? What types of challenges would you face? This publication describes a study that begins to answer these questions. During the study, 11 college students with deaf-blindness were interviewed about their college experiences. They were like most college students in many…

  1. AORTOILIAC AND AORTOFEMORAL RECONSTRUCTION OF OBSTRUCTIVE DISEASE

    NARCIS (Netherlands)

    VANDENAKKER, PJ; VANSCHILFGAARDE, R; BRAND, R; VANBOCKEL, JH; TERPSTRA, JL

    1994-01-01

    This retrospective study evaluates our strategy to limit prosthetic reconstructions for aortoiliac obstructive disease to the diseased segments in 518 patients. There were 363 (70%) reconstructions without femoral anastomotic sites (FEM-0), 107 (21%) reconstructions with one femoral anastomotic site

  2. 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.

  3. Can Acupuncture Treatment Be Double-Blinded? An Evaluation of Double-Blind Acupuncture Treatment of Postoperative Pain

    Science.gov (United States)

    Vase, Lene; Baram, Sara; Takakura, Nobuari; Takayama, Miho; Yajima, Hiroyoshi; Kawase, Akiko; Schuster, Lars; Kaptchuk, Ted J.; Schou, Søren; Jensen, Troels Staehelin; Zachariae, Robert; Svensson, Peter

    2015-01-01

    Blinding protects against bias but the success of blinding is seldom assessed and reported in clinical trials including studies of acupuncture where blinding represents a major challenge. Recently, needles with the potential for double-blinding were developed, so we tested if acupuncture can be double-blinded in a randomized study of sixty-seven patients with acute pain ≥ 3 (0-10 scale following third molar removal) who received active acupuncture with a penetrating needle or placebo acupuncture with a non-penetrating needle. To test if acupuncture was administered double-blind, patients 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. Perceived treatment allocation depended on actual group allocation (p < 0.015) for both patients and acupuncturists, indicating that the needles were not successful in double-blinding. Up to 68% of patients and 83% of acupuncturists correctly identified the treatment, but for patients the distribution was not far from 50/50. Also, there was a significant interaction between actual or perceived treatment and the experience of de qi (p = 0.027), suggesting that the experience of de qi and possible non-verbal clues contributed to correct identification of the treatment. Yet, of the patients who perceived the treatment as active or placebo, 50% and 23%, respectively, reported de qi. Patients’ acute pain levels did not influence the perceived treatment. In conclusion, acupuncture treatment was not fully double-blinded which is similar to observations in pharmacological studies. Still, the non-penetrating needle is the only needle that allows some degree of practitioner blinding. The study raises questions about alternatives to double-blind randomized clinical trials in

  4. Can acupuncture treatment be double-blinded? An evaluation of double-blind acupuncture treatment of postoperative pain.

    Directory of Open Access Journals (Sweden)

    Lene Vase

    Full Text Available Blinding protects against bias but the success of blinding is seldom assessed and reported in clinical trials including studies of acupuncture where blinding represents a major challenge. Recently, needles with the potential for double-blinding were developed, so we tested if acupuncture can be double-blinded in a randomized study of sixty-seven patients with acute pain ≥ 3 (0-10 scale following third molar removal who received active acupuncture with a penetrating needle or placebo acupuncture with a non-penetrating needle. To test if acupuncture was administered double-blind, patients 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. Perceived treatment allocation depended on actual group allocation (p < 0.015 for both patients and acupuncturists, indicating that the needles were not successful in double-blinding. Up to 68% of patients and 83% of acupuncturists correctly identified the treatment, but for patients the distribution was not far from 50/50. Also, there was a significant interaction between actual or perceived treatment and the experience of de qi (p = 0.027, suggesting that the experience of de qi and possible non-verbal clues contributed to correct identification of the treatment. Yet, of the patients who perceived the treatment as active or placebo, 50% and 23%, respectively, reported de qi. Patients' acute pain levels did not influence the perceived treatment. In conclusion, acupuncture treatment was not fully double-blinded which is similar to observations in pharmacological studies. Still, the non-penetrating needle is the only needle that allows some degree of practitioner blinding. The study raises questions about alternatives to double-blind randomized clinical

  5. 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.

  6. 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.

  7. 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.

  8. 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...

  9. 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. PMID:27093062

  10. Orthotopic neobladder reconstruction

    Directory of Open Access Journals (Sweden)

    Dwayne T. S. Chang

    2015-01-01

    Full Text Available Orthotopic neobladder reconstruction is becoming an increasingly common urinary diversion following cystectomy for bladder cancer. This is in recognition of the potential benefits of neobladder surgery over creation of an ileal conduit related to quality of life (QoL, such as avoiding the need to form a stoma with its cosmetic, psychological and other potential complications. The PubMed database was searched using relevant search terms for articles published electronically between January 1994 and April 2014. Full-text articles in English or with English translation were assessed for relevance to the topic before being included in the review. Patients with neobladders have comparable or better post-operative sexual function than those with ileal conduits. They also have comparable QoL to those with ileal conduits. Orthotopic neobladder is a good alternative to ileal conduit in suitable patients who do not want a stoma and are motivated to comply with neobladder training. However, the selection of a neobladder as the urinary diversion of choice requires that patients have good renal and liver functions and are likely to be compliant with neobladder training. With benefits also come potential risks of neobladder formation. These include electrolyte abnormalities and nocturnal incontinence. This short review highlights current aspects of neobladder formation and its potential advantages.

  11. 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.

  12. 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.

  13. Reconstruction tomography from incomplete projections

    International Nuclear Information System (INIS)

    In some instances, reconstruction radionuclide tomography must be carried out from projections that do not include projection values for all portions of the object to be reconstructed. This may occur, for example, when the field of view of the detector is limited, or when an opaque foreign body is present within the object. The effects of such incomplete projections upon reconstructions of computer-simulated phantoms were studied, using iterative and convolution methods. Several methods for reducing the resulting artifacts and inaccuracies are discussed

  14. 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.

  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. Psychosocial characteristics of totally blind people in a Nigerian city

    Directory of Open Access Journals (Sweden)

    Ademola-Popoola Dupe

    2010-01-01

    Full Text Available Purpose: To characterize the demographic and psychosocial problems of a group of blind people as a way of attracting more attention to and providing data that can improve the psychosocial care of the visually impaired. Materials and Method: A cross-sectional descriptive study of a population of totally blind people in Ilorin, Nigeria using a self-report questionnaire (SRQ. The questionnaire was verbally administered by the study personnel in the local language. Simple frequency tables were obtained and the Chi-square test was performed to determine significant differences between variables. P-value <0.05 was considered statistically significant. Results: Sixty one blind patients consented to participate. Most participants were engaged in street begging for their livelihood. Most subjects desired a job change, signifying dissatisfaction with the present occupation. Up to 80% of the cohort was married and had spouses who were also blind in at least one eye. Approximately two-thirds had five or more children and majority lived with family members who were responsible for taking care of their personal hygiene, cooking and mobility. The majority developed blindness in childhood and 16% had a family history of blindness and 77% had never used conventional eye care, with corneal disease being the most frequent cause of blindness. Many feared that their children may also become blind. Thirty-one (51% scored ≥5 on SRQ and were classified as probable cases of psychological disorder. Conclusion: Blindness in a majority of cases that started in childhood was probably preventable. Inaccessibility to or failure of the formal rehabilitation and social welfare systems may have caused this psychosocial dilemma. The high level of social and family interaction provides opportunity for organized preventive ophthalmology, community health care services and psychosocial care.

  17. Optimal image reconstruction phase at low and high heart rates in dual-source CT coronary angiography

    OpenAIRE

    Araoz, Philip A; Kirsch, Jacobo; Primak, Andrew N.; Braun, Natalie N.; Saba, Osama; Williamson, Eric E.; Harmsen, W. Scott; Mandrekar, Jayawant N.; McCollough, Cynthia H.

    2009-01-01

    The purpose of this study was to determine the cardiac phase having the highest coronary sharpness for low and high heart rate patients scanned with dual source CT (DSCT) and to compare coronary image sharpness over different cardiac phases. DSCT coronary CT scans for 30 low heart rate (≤ 70 beats per minute- bpm) and 30 high heart rate (>70 bpm) patients were reconstructed into different cardiac phases, starting at 30% and increasing at 5% increments until 70%. A blinded observer graded imag...

  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. Demonstration of measurement-only blind quantum computing

    Science.gov (United States)

    Greganti, Chiara; Roehsner, Marie-Christine; Barz, Stefanie; Morimae, Tomoyuki; Walther, Philip

    2016-01-01

    Blind quantum computing allows for secure cloud networks of quasi-classical clients and a fully fledged quantum server. Recently, a new protocol has been proposed, which requires a client to perform only measurements. We demonstrate a proof-of-principle implementation of this measurement-only blind quantum computing, exploiting a photonic setup to generate four-qubit cluster states for computation and verification. Feasible technological requirements for the client and the device-independent blindness make this scheme very applicable for future secure quantum networks.

  20. 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.

  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. 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.

  3. Reconstruction techniques for optoacoustic imaging

    Science.gov (United States)

    Frenz, Martin; Koestli, Kornel P.; Paltauf, Guenther; Schmidt-Kloiber, Heinz; Weber, Heinz P.

    2001-06-01

    Optoacoustics is a method to gain information from inside a tissue. This is done by irradiating a tissue with a short light pulse, which generates a pressure distribution inside the tissue that mirrors the absorber distribution. The pressure distribution measured on the tissue-surface allows, by applying a back-projection method, to calculate a tomography image of the absorber distribution. This study presents a novel computational algorithm based on Fourier transform, which, at least in principle, yields an exact 3D reconstruction of the distribution of absorbed energy density inside turbid media. The reconstruction is based on 2D pressure distributions captured outside at different times. The FFT reconstruction algorithm is first tested in the back projection of simulated pressure transients of small model absorbers, and finally applied to reconstruct the distribution of artificial blood vessels in three dimensions.

  4. Vermilion Reconstruction with Genital Mucosa.

    Science.gov (United States)

    Müller-Richter, Urs D A; Weyandt, Gerhard H; Woeckel, Achim; Kübler, Alexander C

    2016-05-01

    Functional and aesthetical reconstruction, especially of the upper lip after ablative tumor surgery, can be very challenging. The skin of the lip might be sufficiently reconstructed by transpositional flaps from the nasolabial or facial area. Large defects of the lip mucosa, including the vestibule, are even more challenging due to the fact that flaps from the inner lining of the oral cavity often lead to functional impairments. We present a case of multiple vermilion and skin resections of the upper lip. At the last step, we had to resect even the whole vermilion mucosa, including parts of the oral mucosa of the vestibule, leaving a bare orbicularis oris muscle. To reconstruct the mucosal layer, we used a mucosal graft from the labia minora and placed it on the compromised lip and the former transpositional flaps for the reconstructed skin of the upper lip with very good functional and aesthetic results. PMID:27579226

  5. 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.

  6. 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.

  7. Provincial reconstruction teams improving effectiveness

    OpenAIRE

    Sellers, Cameron S.

    2007-01-01

    Provincial Reconstruction Teams (PRTs) are currently prominent constructs for stabilization and reconstruction in Afghanistan and Iraq. PRTs are composed of civil-military teams, including elements from coalition partners and the host-nation, and involve multiple military services and civilian agencies. Their missions are to extend the legitimacy of the central government throughout the country and to use Civil Military Operations (CMO) to counter anti-government forces. PRTs are prominent,...

  8. Erectile function after urethral reconstruction

    Institute of Scientific and Technical Information of China (English)

    Joshua Carlton; Maharshi Patel; Allen F. Morey

    2008-01-01

    Advances in urogenital plastic surgical tissue transfer techniques have enabled urethral reconstruction surgery to become the new gold-standard for treatment of refractory urethral stricture disease. Questions remain, however,regarding the long-term implications on sexual function after major genital reconstructive surgery. In this article, we review the pathologic features of urethral stricture disease and urologic trauma that may affect erectile function (EF) and assess the impact of various specific contemporary urethroplasty surgical techniques on male sexual function.

  9. Equilibrium Reconstruction in EAST Tokamak

    Institute of Scientific and Technical Information of China (English)

    QIAN Jinping; WAN Baonian; L. L. LAO; SHEN Biao; S. A. SABBAGH; SUN Youwen; LIU Dongmei; XIAO Singjia; REN Qilong; GONG Xianzu; LI Jiangang

    2009-01-01

    Reconstruction of experimental axisymmetric equilibria is an important part of toka-mak data analysis. Fourier expansion is applied to reconstruct the vessel current distribution in EFIT code. Benchmarking and testing calculations are performed to evaluate and validate this algorithm. Two cases for circular and non-circular plasma discharges are presented. Fourier ex-pansion used to fit the eddy current is a robust method and the real time EFIT can be introduced to the plasma control system in the coming campaign.

  10. 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.

  11. 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.

  12. Phlyctenular keratoconjunctivitis a potentially blinding disorder.

    Science.gov (United States)

    Juberias, J R; Calonge, M; Montero, J; Herreras, J M; Saornil, M A

    1996-01-01

    Phlyctenular keratoconjunctivitis, a delayed hypersensitivity reaction to foreign proteins (i.e., bacterial products), occurs more often in children and young adults sensitized to Staphylococcus aureus inhabiting the lid margins. Clinical manifestations occur on the conjunctiva and/or the cornea. Management strategies used to treat a 14-year-old girl with a long history of keratoconjunctivitis with severe corneal involvement and secondary lacrimal gland enlargement included a complete ocular examination, blood workups, cultures, vigorous lid hygiene, topical antibiotics and steroids, and systemic doxycycline. Phlyctenular keratoconjunctivitis was diagnosed, and Streptoccocus viridans was found colonizing the lid margins and fornices. Subsequent treatment quieted the active inflammation and the secondary lacrimal gland enlargement. However, the residual corneal scarring permanently compromised visual acuity. This patient demonstrates the potentially blinding consequences of untreated phlyctenular keratoconjunctivitis. Moreover, Streptoccocus viridans is not frequently associated with this disorder. To our knowledge hypertrophy of the lacrimal gland, as a secondary complication of this disorder, has not been reported previously. PMID:22827417

  13. Blind Source Separation For Ion Mobility Spectra

    International Nuclear Information System (INIS)

    Miniaturization is a powerful trend for smart chemical instrumentation in a diversity of applications. It is know that miniaturization in IMS leads to a degradation of the system characteristics. For the present work, we are interested in signal processing solutions to mitigate limitations introduced by limited drift tube length that basically involve a loss of chemical selectivity. While blind source separation techniques (BSS) are popular in other domains, their application for smart chemical instrumentation is limited. However, in some conditions, basically linearity, BSS may fully recover the concentration time evolution and the pure spectra with few underlying hypothesis. This is extremely helpful in conditions where non-expected chemical interferents may appear, or unwanted perturbations may pollute the spectra. SIMPLISMA has been advocated by Harrington et al. in several papers. However, more modern methods of BSS for bilinear decomposition with the restriction of positiveness have appeared in the last decade. In order to explore and compare the performances of those methods a series of experiments were performed.

  14. Temporal dynamics of the Venetian blind effect.

    Science.gov (United States)

    Dobias, Joshua Jay; Stine, Wm Wren

    2012-05-01

    When square wave gratings are viewed binocularly with lower luminance or contrast in one eye, the individual bars of the grating appear to rotate around a vertical axis (Venetian blind effect). The effect has typically been thought to occur due to retinal disparities that result from irradiation and, therefore, are entirely entoptic. If so, the visual system should process disparities from a luminance or contrast disparity and a geometric disparity at the same rate. Studies of motion-in-depth using geometric disparities have shown that the visual system is unable to process depth cues when those cues are oscillated at frequencies greater than 5 Hz. By changing contrast (experiments one and two) and geometric (experiment three) disparity cues over time, the present study measured the frequency at which both the perception of motion-in-depth and the perception of depth diminish. The perception of motion-in-depth from contrast disparities decreased near 1.1 Hz (experiments one and four) and the perception of depth from contrast disparities decreased near 1.3 Hz (experiments one, two and four); both of which are lower than the frequency where depth from a geometric disparity diminished (near 4.8 Hz in experiment three). The differences between the dynamics of depth from contrast and geometric disparities suggest that the perception arises from separate neural mechanisms. PMID:22406308

  15. 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.

  16. Causes of blindness in rural Myanmar (Burma: Mount Popa Taung-Kalat Blindness Prevention Project

    Directory of Open Access Journals (Sweden)

    Arie Y Nemet

    2009-07-01

    Full Text Available Arie Y Nemet1, Pinhas Nemet2, Geoff Cohn3, Gina Sutton, Gerald Sutton4, Richard Rawson41Department of Ophthalmology, Sydney Hospital and Sydney Eye Hospital, Sydney, Australia; 2Sackler School of Medicine, Tel-Aviv University, Israel; 3Departments of Ophthalmology, University of New South Wales, Sydney, Australia; 4Department of Ophthalmology, University of Sydney, AustraliaPurpose: This study is a review of the major causes of visual impairment (VI and severe visual impairment/blindness (SVI/BL in Mount Popa Taung-Kalat, a rural region in Myanmar (Burma.Methods: A review of our clinical records of consecutive patients attending clinics was conducted. Participants of all ages (n = 650 of the population of Mount Popa Taung-Kalat and villages in its vicinity underwent ophthalmic interview and a detailed dilated ocular evaluation by trained Australian ophthalmologists and ophthalmic nurses. This evaluation included anterior segment examination with a slit lamp, intraocular pressure recording, and direct or indirect ophthalmoscopy. VI and SVI/BL were defined by the World Health Organization (WHO criteria. Results: Six hundred fifty subjects were screened, with a mean age of 49.0 ± 20.6 years (range, 1–99. One hundred five patients (16.2% were children (ages 1–18. Five hundred thirty-one eyes of the total 1,300 eyes (39.5% had VI/SVI/BL, and 40 eyes of the children (38.1% (average age 15.3 ± 13.3 had VI/SVI/BL. The leading causes of VI/SVI/BL were cataract with 288 cases (54.2%, glaucoma with 84 cases (15.8%, and corneal pathology with 78 cases (14.7%. Of all the VI/SVI/BL cases, 8.4% were preventable, 81.9% were treatable, and total of 90.5% were avoidable.Conclusions: In the current study, cataracts were the major cause of blindness and visual impairment, and most of the ophthalmic pathology causing blindness is avoidable. These results highlight the lack of basic ophthalmologist eye care and optician resources in rural regions in Myanmar

  17. [Enlightenment and thinking of blinding trachoma elimination in China].

    Science.gov (United States)

    Wang, Ningli; Hu, Ailian

    2015-07-01

    Trachoma had been the leading infectious cause of blindness. After years of hard work and unremitting efforts, blinding trachoma would never been a public health problem in China by 2015. Discovery and research of Chlamydia trachoma provide a scientific way for the prevention and control of trachoma. The achievement of eliminating blinding trachoma in China pertained to the highly concerned about government and succeed spreading of SAFE strategies. It is still required to strengthen the diagnostic criteria and knowledge training of public health disease. Epidemiological investigation should follow the international criteria. Though blinding trachoma would never been a public health problem in China, comprehensive prevention and control of trachoma should be emphasized in case of being epidemic again. PMID:26310249

  18. Computer Simulation to Detect the Blind Spots in Automobiles

    Directory of Open Access Journals (Sweden)

    Hazem (moh'd Said Hatamleh

    2013-01-01

    Full Text Available During driving Changing lanes can be very hazardous on a busy highway. There is region called "blind spot" which is a problem for every car driver since its not covered by the drivers mirrors. Relying solely on the mirrors while changing lane can lead to a collision with another vehicle. This paper focuses on this situation by ensuring that the blind spots of the vehicle are clear prior to the driver attempt to change lanes. This computer simulation incorporates the need for detection and warning of objects present within the blind spot on either side of the vehicle to the driver along with distance measurement of the object relative to the vehicle, incase the driver decides to change lanes. This simulation is constructed using the theory of embedded systems and will alert the driver if there is another car on the blind area.

  19. The Preschool Blind Child Can Be a Cane User.

    Science.gov (United States)

    Pogrund, R. L.; Rosen, S. J.

    1989-01-01

    This article proposes the teaching of long cane mobility skills to blind preschool-age children. Traditional arguments against early cane use are refuted and possible advantages of early use identified. Strategies and techniques for cane introduction are specified. (DB)

  20. Inattentional blindness is influenced by exposure time not motion speed.

    Science.gov (United States)

    Kreitz, Carina; Furley, Philip; Memmert, Daniel

    2016-01-01

    Inattentional blindness is a striking phenomenon in which a salient object within the visual field goes unnoticed because it is unexpected, and attention is focused elsewhere. Several attributes of the unexpected object, such as size and animacy, have been shown to influence the probability of inattentional blindness. At present it is unclear whether or how the speed of a moving unexpected object influences inattentional blindness. We demonstrated that inattentional blindness rates are considerably lower if the unexpected object moves more slowly, suggesting that it is the mere exposure time of the object rather than a higher saliency potentially induced by higher speed that determines the likelihood of its detection. Alternative explanations could be ruled out: The effect is not based on a pop-out effect arising from different motion speeds in relation to the primary-task stimuli (Experiment 2), nor is it based on a higher saliency of slow-moving unexpected objects (Experiment 3). PMID:26031845

  1. Retinopathy of prematurity blindness worldwide: phenotypes in the third epidemic

    Directory of Open Access Journals (Sweden)

    Quinn GE

    2016-05-01

    Full Text Available Graham E Quinn Division of Ophthalmology, The Children’s Hospital of Philadelphia, Wood Center, Philadelphia, PA, USA Abstract: Blindness due to retinopathy of prematurity (ROP is an increasing problem worldwide as improved levels of neonatal care are provided in countries with developing neonatal intensive care units. The occurrence of ROP blindness varies dramatically with the socioeconomic development of a country. In regions with high levels of neonatal care and adequate resources, ROP blindness is largely restricted to premature infants with very low birth weight and low gestational age while in middle- and low-income countries with regional variation in technology and capacity, limited health resources may well limit the care of the premature newborn. Keywords: ROP, international, blindness

  2. 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...

  3. Natural ventilation in the double skin facade with venetian blind

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Xiao-li [Thermal Energy Research Institute, Tianjin University, Weijin Road No. 92, Tianjin 300072 (China); China Electronics Engineering Design Institute, Beijing 100083 (China); Yang, Zhao [Thermal Energy Research Institute, Tianjin University, Weijin Road No. 92, Tianjin 300072 (China)

    2008-07-01

    As a new-style building, the thermal performance of double skin facade with the venetian blind cannot be predicted for the absence of suitable tool. In the paper, a detailed analysis of the thermal process in glass double facade with venetian blind was made. The governing equations were solved by comprising CFD, optical and heat balance model for multi-layer transparent system. It is shown that the more complex natural ventilation exists in the two air gaps divided by venetian blind, which cannot be reflected with the simplified model. Comparing the simulation results with the experiment data in the literature, a good agreement was achieved. Hence, it can be used as a reliable tool to analyze the ventilation in the double skin facade with a venetian blind. (author)

  4. Parenting Styles and the Depressive Syndrome in Congenitally Blind Individuals.

    Science.gov (United States)

    Lambert, Robert; West, Malcolm

    1980-01-01

    The article discusses the effect on congenitally blind children of three types of parents: those who are overprotective, those who push the child toward independence too soon, and those who are "good enough." (Author)

  5. 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

    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......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...... their sighted counterparts. These results confirm that orthonasal but not retronasal olfactory perception is enhanced in congenital blindness, a result that is concordant with the reduced food variety exposure in this group....

  6. 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.

  7. 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...... subjects more strongly activated primary (right amygdala) and secondary (right orbitofrontal cortex and bilateral hippocampus) olfactory areas. In addition, widespread task-related activations were found throughout the whole extent of the occipital cortex in blind but not in sighted participants...

  8. 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

  9. INCLUSIVE EDUCATION OF BLIND AND VISUALLY IMPAIRED PUPILS IN SLOVENIA

    OpenAIRE

    Cankar, Franc; Deutsch, Tomi; GLOBACNIK Bojana; PINTERIC Andreja

    2015-01-01

    Introduction: In the last years, the demand to include children with special needs in the mainstream kindergartens and schools in Slovenia has grown. This brought with it the need for changing the role of the special schools and institutes for children with special needs and for their transformation into resource centres. Methodology: We pilot tested a resource centre for support of blind and visually impaired children. We included 15 educational institutes and one blind or visually impair...

  10. AAV Gene Therapy for MPS1-associated Corneal Blindness

    OpenAIRE

    Melisa Vance; Telmo Llanga; Will Bennett; Kenton Woodard; Giridhar Murlidharan; Neil Chungfat; Aravind Asokan; Brian Gilger; Joanne Kurtzberg; Jude Samulski, R.; Hirsch, Matthew L.

    2016-01-01

    Although cord blood transplantation has significantly extended the lifespan of mucopolysaccharidosis type 1 (MPS1) patients, over 95% manifest cornea clouding with about 50% progressing to blindness. As corneal transplants are met with high rejection rates in MPS1 children, there remains no treatment to prevent blindness or restore vision in MPS1 children. Since MPS1 is caused by mutations in idua, which encodes alpha-L-iduronidase, a gene addition strategy to prevent, and potentially reverse...

  11. Simplified solar optical calculations for windows with venetian blinds

    Energy Technology Data Exchange (ETDEWEB)

    Kotey, N.A.; Wright, J.L. [Waterloo Univ., ON (Canada). Dept. of Mechanical Engineering

    2006-07-01

    Solar gain through a window represents the largest and most variable heat gain imposed on an indoor space. The potential for shading devices to optimize the energy efficiency of buildings was discussed with reference to the value of modeling complex fenestration system in annual energy simulation programs. Shading devices such as venetian blinds, roller blinds and drapes are commonly used to control solar gain through windows. In this paper, three sets of calculations were presented for a window with light and dark coloured venetian blinds using simplified models and computational procedures. Hourly transmitted, reflected and absorbed fluxes were calculated for both summer and winter conditions with a venetian blind placed on the indoor-side of the window; a venetian blind placed between the glazings; and, a venetian blind placed on the outdoor-side of the window. As the first step in energy analysis of the complex fenestration systems, short-wave radiation models determine the fraction of incident solar radiation directly transmitted through the complex fenestration system and the fraction that is absorbed in each layer. The absorbed solar energy in each layer serves as a source term for the heat transfer analysis. In this study, simplified models were used to calculate the transmitted, reflected and absorbed fluxes of solar radiation for windows with venetian blinds. The study showed that a particular configuration of a window with a venetian blind can significantly influence the amount of energy transmitted to the indoor space at different times of the year. In addition, the slat angle could reduce the building energy requirements during the summer and winter seasons. The simplified calculation procedures produced results that can serve as useful input to building load and annual energy calculation tools. 9 refs., 2 tabs., 10 figs.

  12. Retinopathy of prematurity blindness worldwide: phenotypes in the third epidemic

    OpenAIRE

    Quinn, Graham

    2016-01-01

    Graham E Quinn Division of Ophthalmology, The Children’s Hospital of Philadelphia, Wood Center, Philadelphia, PA, USA Abstract: Blindness due to retinopathy of prematurity (ROP) is an increasing problem worldwide as improved levels of neonatal care are provided in countries with developing neonatal intensive care units. The occurrence of ROP blindness varies dramatically with the socioeconomic development of a country. In regions with high levels of neonatal care and adequate resou...

  13. Retinopathy of prematurity blindness worldwide: phenotypes in the third epidemic

    OpenAIRE

    Quinn GE

    2016-01-01

    Graham E Quinn Division of Ophthalmology, The Children’s Hospital of Philadelphia, Wood Center, Philadelphia, PA, USA Abstract: Blindness due to retinopathy of prematurity (ROP) is an increasing problem worldwide as improved levels of neonatal care are provided in countries with developing neonatal intensive care units. The occurrence of ROP blindness varies dramatically with the socioeconomic development of a country. In regions with high levels of neonatal care and adequate resources...

  14. 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.

  15. Comparison of Knee Proprioception Between Blind and Healthy Sportsmen

    OpenAIRE

    Şilil, Mehtap Kaçmaz; Sargın, Serdar; Atik, Aziz; Meriç, Gökhan; Özer, Muhammet; Akseki, Devrim

    2014-01-01

    Objectives: Visual sense and proprioception have a big role in motion control. Visual communication ensures the data in proprioceptive period. The other senses of blind people are improved because of the lack of the visual ability but there are not enough data for the proprioceptive quality. The purpose of this study is to compare the knee joint proprioception of the blind and normal sportsmen and figure out the prorioceptive quality. Methods: 16 visually-challenged sportsmen (12 males and 4 ...

  16. 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.

  17. Semi-Blind Cancellation of IQ-Imbalances

    OpenAIRE

    Hesse, Matthias; Mailand, Marko; Jentschel, Hans-Joachim; Deneire, Luc; Lebrun, Jerome

    2008-01-01

    The technical realization of modern wireless receivers yields significant interfering IQ-imbalances, which have to be compensated digitally. To cancel these IQ-imbalances, we propose an algorithm using iterative blind source separation (IBSS) as well as information about the modulation scheme used (hence the term semi-blind). The novelty of our approach lies in the fact that we match the nonlinearity involved in the IBSS algorithm to the probability density function of the source signals. Mor...

  18. Implicit binding of facial features during change blindness

    OpenAIRE

    Pessi Lyyra; Hanna Mäkelä; Hietanen, Jari K.; Piia Astikainen

    2014-01-01

    Abstract. Change blindness refers to the inability to detect visual changes if introduced together with an eye-movement, blink, flash of light, or with distracting stimuli. Evidence of implicit detection of changed visual features during change blindness has been reported in a number of studies using both behavioral and neurophysiological measurements. However, it is not known whether implicit detection occurs only at the level of single features or whether complex organizations of f...

  19. 20 CFR 404.1582 - A period of disability based on blindness.

    Science.gov (United States)

    2010-04-01

    ..., SURVIVORS AND DISABILITY INSURANCE (1950- ) Determining Disability and Blindness Blindness § 404.1582 A... entitled to receive disability insurance cash benefits even though you are blind. If you are a blind person... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false A period of disability based on...

  20. 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…

  1. 20 CFR 416.903 - Who makes disability and blindness determinations.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Who makes disability and blindness... INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Determinations § 416.903 Who makes disability and blindness determinations. (a) State agencies. State agencies make...

  2. 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.

  3. Implicit binding of facial features during change blindness.

    Directory of Open Access Journals (Sweden)

    Pessi Lyyra

    Full Text Available Change blindness refers to the inability to detect visual changes if introduced together with an eye-movement, blink, flash of light, or with distracting stimuli. Evidence of implicit detection of changed visual features during change blindness has been reported in a number of studies using both behavioral and neurophysiological measurements. However, it is not known whether implicit detection occurs only at the level of single features or whether complex organizations of features can be implicitly detected as well. We tested this in adult humans using intact and scrambled versions of schematic faces as stimuli in a change blindness paradigm while recording event-related potentials (ERPs. An enlargement of the face-sensitive N170 ERP component was observed at the right temporal electrode site to changes from scrambled to intact faces, even if the participants were not consciously able to report such changes (change blindness. Similarly, the disintegration of an intact face to scrambled features resulted in attenuated N170 responses during change blindness. Other ERP deflections were modulated by changes, but unlike the N170 component, they were indifferent to the direction of the change. The bidirectional modulation of the N170 component during change blindness suggests that implicit change detection can also occur at the level of complex features in the case of facial stimuli.

  4. 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.

  5. 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.

  6. 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.

  7. Implicit binding of facial features during change blindness.

    Science.gov (United States)

    Lyyra, Pessi; Mäkelä, Hanna; Hietanen, Jari K; Astikainen, Piia

    2014-01-01

    Change blindness refers to the inability to detect visual changes if introduced together with an eye-movement, blink, flash of light, or with distracting stimuli. Evidence of implicit detection of changed visual features during change blindness has been reported in a number of studies using both behavioral and neurophysiological measurements. However, it is not known whether implicit detection occurs only at the level of single features or whether complex organizations of features can be implicitly detected as well. We tested this in adult humans using intact and scrambled versions of schematic faces as stimuli in a change blindness paradigm while recording event-related potentials (ERPs). An enlargement of the face-sensitive N170 ERP component was observed at the right temporal electrode site to changes from scrambled to intact faces, even if the participants were not consciously able to report such changes (change blindness). Similarly, the disintegration of an intact face to scrambled features resulted in attenuated N170 responses during change blindness. Other ERP deflections were modulated by changes, but unlike the N170 component, they were indifferent to the direction of the change. The bidirectional modulation of the N170 component during change blindness suggests that implicit change detection can also occur at the level of complex features in the case of facial stimuli. PMID:24498165

  8. 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.

  9. 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

  10. 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

  11. 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

  12. 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.

  13. 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.

  14. Causes of childhood blindness in the northeastern states of India

    Directory of Open Access Journals (Sweden)

    Bhattacharjee Harsha

    2008-01-01

    Full Text Available Background: The northeastern region (NER of India is geographically isolated and ethno-culturally different from the rest of the country. There is lacuna regarding the data on causes of blindness and severe visual impairment in children from this region. Aim: To determine the causes of severe visual impairment and blindness amongst children from schools for the blind in the four states of NER of India. Design and Setting: Survey of children attending special education schools for the blind in the NER. Materials and Methods: Blind and severely visually impaired children (best corrected visual acuity < 20/200 in the better eye, aged up to 16 years underwent visual acuity estimation, external ocular examination, retinoscopy and fundoscopy. Refraction and low vision workup was done where indicated. World Health Organization′s reporting form was used to code anatomical and etiological causes of visual loss. Statistical Analysis: Microsoft Excel Windows software with SPSS. Results: A total of 376 students were examined of whom 258 fulfilled the eligibility criteria. The major anatomical causes of visual loss amongst the 258 were congenital anomalies (anophthalmos, microphthalmos 93 (36.1%; corneal conditions (scarring, vitamin A deficiency 94 (36.7%; cataract or aphakia 28 (10.9%, retinal disorders 15 (5.8% and optic atrophy 14 (5.3%. Nearly half of the children were blind from conditions which were either preventable or treatable (48.5%. Conclusion: Nearly half the childhood blindness in the NER states of India is avoidable and Vitamin A deficiency forms an important component unlike other Indian states. More research and multisectorial effort is needed to tackle congenital anomalies.

  15. 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

  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. The reconstruction of inflationary potentials

    Science.gov (United States)

    Lin, Jianmang; Gao, Qing; Gong, Yungui

    2016-07-01

    The observational data on the anisotropy of the cosmic microwave background constraints the scalar spectral tilt ns and the tensor to scalar ratio r which depend on the first and second derivatives of the inflaton potential. The information can be used to reconstruct the inflaton potential in the polynomial form up to some orders. However, for some classes of potentials, ns and r behave as ns(N) and r(N) universally in terms of the number of e-folds N. The universal behaviour of ns(N) can be used to reconstruct a class of inflaton potentials. By parametrizing one of the parameters ns(N), ɛ(N) and φ(N), and fitting the parameters in the models to the observational data, we obtain the constraints on the parameters and reconstruct the classes of the inflationary models which include the chaotic inflation, T-model, hilltop inflation, s-dual inflation, natural inflation and R2 inflation.

  18. 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...

  19. Reconstructing Ancient Forms of Life

    Science.gov (United States)

    Benner, Steven A.

    1998-01-01

    Progress in the past three months has occurred in two areas, reconstruction of ancestral proteins and improved understanding of chemical features that are likely to be universal in generic matter regardless of its genesis. Ancestral ribonucleases have been reconstructed, and an example has been developed that shows how physiological function can be assigned to in vitro behaviors observed in biological systems. Sequence data have been collected to permit the reconstruction of src homology 2 domains that underwent radiative divergence at the time of the radiative divergence of chordates. New studies have been completed that show how genetic matter (or its remnants) might be detected on Mars (or other non-terrean locations.) Last, the first in vitro selection experiments have been completed using a nucleoside library carrying positively charged functionality, illustrating the importance of non-standard nucleotides to those attempting to obtain evidence for an "RNA world" as an early episode of life on earth.

  20. 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

  1. Using state-of-the-art inverse problem techniques to develop reconstruction methods for fluorescence diffuse optical

    OpenAIRE

    Chamorro Servent, Judit

    2013-01-01

    An inverse problem is a mathematical framework that is used to obtain info about a physical object or system from observed measurements. It usually appears when we wish to obtain information about internal data from outside measurements and has many applications in science and technology such as medical imaging, geophysical imaging, image deblurring, image inpainting, electromagnetic scattering, acoustics, machine learning, mathematical finance, physics, etc. The main goal o...

  2. 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.

  3. Reconstructing WKB from topological recursion

    CERN Document Server

    Bouchard, Vincent

    2016-01-01

    We prove that the topological recursion reconstructs the WKB expansion of a quantum curve for all spectral curves whose Newton polygons have no interior point (and that are smooth as affine curves). This includes nearly all previously known cases in the literature, and many more; in particular, it includes many quantum curves of order greater than two. We also explore the connection between the choice of ordering in the quantization of the spectral curve and the choice of integration divisor to reconstruct the WKB expansion.

  4. 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.

  5. The scene and the unseen: manipulating photographs for experiments on change blindness and scene memory: image manipulation for change blindness.

    Science.gov (United States)

    Ball, Felix; Elzemann, Anne; Busch, Niko A

    2014-09-01

    The change blindness paradigm, in which participants often fail to notice substantial changes in a scene, is a popular tool for studying scene perception, visual memory, and the link between awareness and attention. Some of the most striking and popular examples of change blindness have been demonstrated with digital photographs of natural scenes; in most studies, however, much simpler displays, such as abstract stimuli or "free-floating" objects, are typically used. Although simple displays have undeniable advantages, natural scenes remain a very useful and attractive stimulus for change blindness research. To assist researchers interested in using natural-scene stimuli in change blindness experiments, we provide here a step-by-step tutorial on how to produce changes in natural-scene images with a freely available image-processing tool (GIMP). We explain how changes in a scene can be made by deleting objects or relocating them within the scene or by changing the color of an object, in just a few simple steps. We also explain how the physical properties of such changes can be analyzed using GIMP and MATLAB (a high-level scientific programming tool). Finally, we present an experiment confirming that scenes manipulated according to our guidelines are effective in inducing change blindness and demonstrating the relationship between change blindness and the physical properties of the change and inter-individual differences in performance measures. We expect that this tutorial will be useful for researchers interested in studying the mechanisms of change blindness, attention, or visual memory using natural scenes. PMID:24311058

  6. 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.

  7. 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.

  8. 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.

  9. 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,

  10. Representation of haptic objects during mental rotation in congenital blindness.

    Science.gov (United States)

    Güçlü, Burak; Celik, Serkan; Ilci, Civan

    2014-04-01

    The representation of haptic objects by three groups of participants (sighted, blindfolded, and congenitally blind) was studied in a mental-rotation task. Three models were tested. The participants explored a standard object continuously with the left hand and tried to find the mirror object among two alternatives explored sequentially with the right hand. Sighted participants were tested in the visual version of the task. The accuracy of judgments was very high (> 95%) for all groups, and the blind group had the highest identification times. Correlation analyses were performed between (both single-trial and average) identification times and angular differences. The identification times of the sighted and blindfolded groups increased as linear functions of the angular difference between the mirror and the standard stimuli, supporting the classical model. The identification times of the blind group changed non-monotonically and were consistent with an antiparallel image (180 degrees rotation superimposed) in the mental representation. The dual code model did not fit the data well for any participant group. The performance differences between the blindfolded and blind groups may be attributed to a modified mapping function from the object-properties-processing sub-system to the visual buffer, which was conjectured to be available also to the blind group while processing haptic objects. PMID:24897889

  11. 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.

  12. Breast Reconstruction with Tissue Expansion

    Medline Plus

    Full Text Available RECONSTRUCTIVE BREAST SURGERY ALBANY MEDICAL CENTER HOSPITAL ALBANY, NY July 31, 2008 00:00:10 ANNOUNCER: Welcome to this OR-Live webcast presentation, brought to ... webcast screen and open the door to informed medical care. 00:00:28 DIMITRI KOUMANIS, M.D.: ...

  13. 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.

  14. Change-readiness of the blind: A hospital based study in a coastal town of South India

    Directory of Open Access Journals (Sweden)

    Ramya Shetty

    2014-01-01

    Conclusion: The results suggest that there is a need to modify health policy to include blind rehabilitation, to improve visibility of blind rehabilitation centers, to include family members and co-professionals while managing the blind so that we treat the "blind person" and not a "pair of blind eyes."

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

    DEFF Research Database (Denmark)

    Vargas Brenes, Ronald

    converge, each defined by the variety of student practices. As a strategy universities should incorporate inclusion topics in the curricula to teach their students about their responsibility to establish inclusion in their future work. This strategy is discussed as an efficient tool for improving...... on Braille to read and write, and partially sighted people who can read printed material with the use of magnifiers or other supportive tools. The social construction of blindness, drawing on four different models: the charity model, the medical model, the rights-based model and the economic model. A...... the understanding of blindness and for easing the negotiability of practices between different populations. Therefore, this strategy contributes to the inclusion of blind students in these educational environments. Specialised offices in each university will benefit the incorporation of policies, knowledge...

  16. An ID-based Blind Signature Scheme from Bilinear Pairings

    Directory of Open Access Journals (Sweden)

    B.Umaprasada Rao

    2010-03-01

    Full Text Available Blind signatures, introduced by Chaum, allow a user to obtain a signature on a message without revealing any thing about the message to the signer. Blind signatures play on important role in plenty of applications such as e-voting, e-cash system where anonymity is of great concern. Identity based(ID-based public key cryptography can be a good alternative for certified based public key setting, especially when efficient key management and moderate security are required. In this paper, we propose an ID-based blind signature scheme from bilinear pairings. The proposed scheme is based on the Hess ID- based digital signature scheme. Also we analyze security and efficiency of the proposed scheme.

  17. Blind loop perforation after side-to-side ileocolonic anastomosis.

    Science.gov (United States)

    Valle, Raffaele Dalla; Zinicola, Roberto; Iaria, Maurizio

    2014-08-27

    Blind loop syndrome after side-to-side ileocolonic anastomosis is a well-recognized entity even though its incidence and complication rates are not clearly defined. The inevitable dilation of the ileal cul-de-sac leads to stasis and bacterial overgrowth which eventually leads to mucosal ulceration and even full-thickness perforation. Blind loop syndrome may be an underestimated complication in the setting of digestive surgery. It should always be taken into account in cases of acute abdomen in patients who previously underwent right hemicolectomy. We herein report 3 patients who were diagnosed with perforative blind loop syndrome a few years after standard right hemicolectomy followed by a side-to-side ileocolonic anastomosis.

  18. Blind loop perforation after side-to-side ileocolonic anastomosis

    Institute of Scientific and Technical Information of China (English)

    Raffaele; Dalla; Valle; Roberto; Zinicola; Maurizio; Iaria

    2014-01-01

    Blind loop syndrome after side-to-side ileocolonic anas-tomosis is a well-recognized entity even though its in-cidence and complication rates are not clearly defined. The inevitable dilation of the ileal cul-de-sac leads to stasis and bacterial overgrowth which eventually leads to mucosal ulceration and even full-thickness perfora-tion. Blind loop syndrome may be an underestimated complication in the setting of digestive surgery. It should always be taken into account in cases of acute abdomen in patients who previously underwent right hemicolectomy. We herein report 3 patients who were diagnosed with perforative blind loop syndrome a few years after standard right hemicolectomy followed by a side-to-side ileocolonic anastomosis.

  19. Countermeasures Against Blinding Attack on Superconducting Nanowire Detectors for QKD

    Directory of Open Access Journals (Sweden)

    Elezov M.S.

    2015-01-01

    Full Text Available Nowadays, the superconducting single-photon detectors (SSPDs are used in Quantum Key Distribution (QKD instead of single-photon avalanche photodiodes. Recently bright-light control of the SSPD has been demonstrated. This attack employed a “backdoor” in the detector biasing technique. We developed the autoreset system which returns the SSPD to superconducting state when it is latched. We investigate latched state of the SSPD and define limit conditions for effective blinding attack. Peculiarity of the blinding attack is a long nonsingle photon response of the SSPD. It is much longer than usual single photon response. Besides, we need follow up response duration of the SSPD. These countermeasures allow us to prevent blind attack on SSPDs for Quantum Key Distribution.

  20. Ancestral reconstruction of tick lineages.

    Science.gov (United States)

    Mans, Ben J; de Castro, Minique H; Pienaar, Ronel; de Klerk, Daniel; Gaven, Philasande; Genu, Siyamcela; Latif, Abdalla A

    2016-06-01

    Ancestral reconstruction in its fullest sense aims to describe the complete evolutionary history of a lineage. This depends on accurate phylogenies and an understanding of the key characters of each parental lineage. An attempt is made to delineate our current knowledge with regard to the ancestral reconstruction of the tick (Ixodida) lineage. Tick characters may be assigned to Core of Life, Lineages of Life or Edges of Life phenomena depending on how far back these characters may be assigned in the evolutionary Tree of Life. These include housekeeping genes, sub-cellular systems, heme processing (Core of Life), development, moulting, appendages, nervous and organ systems, homeostasis, respiration (Lineages of Life), specific adaptations to a blood-feeding lifestyle, including the complexities of salivary gland secretions and tick-host interactions (Edges of Life). The phylogenetic relationships of lineages, their origins and importance in ancestral reconstruction are discussed. Uncertainties with respect to systematic relationships, ancestral reconstruction and the challenges faced in comparative transcriptomics (next-generation sequencing approaches) are highlighted. While almost 150 years of information regarding tick biology have been assembled, progress in recent years indicates that we are in the infancy of understanding tick evolution. Even so, broad reconstructions can be made with relation to biological features associated with various lineages. Conservation of characters shared with sister and parent lineages are evident, but appreciable differences are present in the tick lineage indicating modification with descent, as expected for Darwinian evolutionary theory. Many of these differences can be related to the hematophagous lifestyle of ticks. PMID:26868413

  1. Stability indicators in network reconstruction.

    Science.gov (United States)

    Filosi, Michele; Visintainer, Roberto; Riccadonna, Samantha; Jurman, Giuseppe; Furlanello, Cesare

    2014-01-01

    The number of available algorithms to infer a biological network from a dataset of high-throughput measurements is overwhelming and keeps growing. However, evaluating their performance is unfeasible unless a 'gold standard' is available to measure how close the reconstructed network is to the ground truth. One measure of this is the stability of these predictions to data resampling approaches. We introduce NetSI, a family of Network Stability Indicators, to assess quantitatively the stability of a reconstructed network in terms of inference variability due to data subsampling. In order to evaluate network stability, the main NetSI methods use a global/local network metric in combination with a resampling (bootstrap or cross-validation) procedure. In addition, we provide two normalized variability scores over data resampling to measure edge weight stability and node degree stability, and then introduce a stability ranking for edges and nodes. A complete implementation of the NetSI indicators, including the Hamming-Ipsen-Mikhailov (HIM) network distance adopted in this paper is available with the R package nettools. We demonstrate the use of the NetSI family by measuring network stability on four datasets against alternative network reconstruction methods. First, the effect of sample size on stability of inferred networks is studied in a gold standard framework on yeast-like data from the Gene Net Weaver simulator. We also consider the impact of varying modularity on a set of structurally different networks (50 nodes, from 2 to 10 modules), and then of complex feature covariance structure, showing the different behaviours of standard reconstruction methods based on Pearson correlation, Maximum Information Coefficient (MIC) and False Discovery Rate (FDR) strategy. Finally, we demonstrate a strong combined effect of different reconstruction methods and phenotype subgroups on a hepatocellular carcinoma miRNA microarray dataset (240 subjects), and we validate the

  2. Stability indicators in network reconstruction.

    Directory of Open Access Journals (Sweden)

    Michele Filosi

    Full Text Available The number of available algorithms to infer a biological network from a dataset of high-throughput measurements is overwhelming and keeps growing. However, evaluating their performance is unfeasible unless a 'gold standard' is available to measure how close the reconstructed network is to the ground truth. One measure of this is the stability of these predictions to data resampling approaches. We introduce NetSI, a family of Network Stability Indicators, to assess quantitatively the stability of a reconstructed network in terms of inference variability due to data subsampling. In order to evaluate network stability, the main NetSI methods use a global/local network metric in combination with a resampling (bootstrap or cross-validation procedure. In addition, we provide two normalized variability scores over data resampling to measure edge weight stability and node degree stability, and then introduce a stability ranking for edges and nodes. A complete implementation of the NetSI indicators, including the Hamming-Ipsen-Mikhailov (HIM network distance adopted in this paper is available with the R package nettools. We demonstrate the use of the NetSI family by measuring network stability on four datasets against alternative network reconstruction methods. First, the effect of sample size on stability of inferred networks is studied in a gold standard framework on yeast-like data from the Gene Net Weaver simulator. We also consider the impact of varying modularity on a set of structurally different networks (50 nodes, from 2 to 10 modules, and then of complex feature covariance structure, showing the different behaviours of standard reconstruction methods based on Pearson correlation, Maximum Information Coefficient (MIC and False Discovery Rate (FDR strategy. Finally, we demonstrate a strong combined effect of different reconstruction methods and phenotype subgroups on a hepatocellular carcinoma miRNA microarray dataset (240 subjects, and we

  3. Deblurring for spatial and temporal varying motion with optical computing

    Science.gov (United States)

    Xiao, Xiao; Xue, Dongfeng; Hui, Zhao

    2016-05-01

    A way to estimate and remove spatially and temporally varying motion blur is proposed, which is based on an optical computing system. The translation and rotation motion can be independently estimated from the joint transform correlator (JTC) system without iterative optimization. The inspiration comes from the fact that the JTC system is immune to rotation motion in a Cartesian coordinate system. The work scheme of the JTC system is designed to keep switching between the Cartesian coordinate system and polar coordinate system in different time intervals with the ping-pang handover. In the ping interval, the JTC system works in the Cartesian coordinate system to obtain a translation motion vector with optical computing speed. In the pang interval, the JTC system works in the polar coordinate system. The rotation motion is transformed to the translation motion through coordinate transformation. Then the rotation motion vector can also be obtained from JTC instantaneously. To deal with continuous spatially variant motion blur, submotion vectors based on the projective motion path blur model are proposed. The submotion vectors model is more effective and accurate at modeling spatially variant motion blur than conventional methods. The simulation and real experiment results demonstrate its overall effectiveness.

  4. Color blindness among multiple sclerosis patients in Isfahan

    Directory of Open Access Journals (Sweden)

    Vahid Shaygannejad

    2012-01-01

    Full Text Available Background: Multiple sclerosis (MS is a disease of young and middle aged individuals with a demyelinative axonal damage nature in central nervous system that causes various signs and symptoms. As color vision needs normal function of optic nerve and macula, it is proposed that MS can alter it via influencing optic nerve. In this survey, we evaluated color vision abnormalities and its relationship with history of optic neuritis and abnormal visual evoked potentials (VEPs among MS patients. Materials and Methods: The case group was included of clinically definitive MS patients and the same number of normal population was enrolled as the control group. Color vision of all the participants was evaluated by Ishihara test and then visual evoked potential (VEPs and history of optic neuritis (ON was assessed among them. Then, frequency of color blindness was compared between the case and the control group. Finally, color blinded patients were compared to those with the history of ON and abnormal VEPs. Results: 63 MS patients and the same number of normal populations were enrolled in this study. 12 patients had color blindness based on the Ishihara test; only 3 of them were among the control group, which showed a significant different between the two groups (P = 0.013. There was a significant relationship between the color blindness and abnormal VEP (R = 0.53, P = 0.023 but not for the color blindness and ON (P = 0.67. Conclusions: This study demonstrates a significant correlation between color blindness and multiple sclerosis including ones with abnormal prolonged VEP latencies. Therefore, in individuals with acquired color vision impairment, an evaluation for potentially serious underlying diseases like MS is essential.

  5. Designing Motion Gesture Interfaces in Mobile Phones for Blind People

    Institute of Scientific and Technical Information of China (English)

    任向实

    2014-01-01

    Despite the existence of advanced functions in smartphones, most blind people are still using old-fashioned phones with familiar layouts and dependence on tactile buttons. Smartphones support accessibility features including vibration, speech and sound feedback, and screen readers. However, these features are only intended to provide feedback to user commands or input. It is still a challenge for blind people to discover functions on the screen and to input the commands. Although voice commands are supported in smartphones, these commands are difficult for a system to recognize in noisy environments. At the same time, smartphones are integrated with sophisticated motion sensors, and motion gestures with device tilt have been gaining attention for eyes-free input. We believe that these motion gesture interactions offer more efficient access to smartphone functions for blind people. However, most blind people are not smartphone users and they are aware of neither the affordances available in smartphones nor the potential for interaction through motion gestures. To investigate the most usable gestures for blind people, we conducted a user-defined study with 13 blind participants. Using the gesture set and design heuristics from the user study, we implemented motion gesture based interfaces with speech and vibration feedback for browsing phone books and making a call. We then conducted a second study to investigate the usability of the motion gesture interface and user experiences using the system. The findings indicated that motion gesture interfaces are more efficient than traditional button interfaces. Through the study results, we provided implications for designing smartphone interfaces.

  6. Evaluation of children in six blind schools of Andhra Pradesh

    Directory of Open Access Journals (Sweden)

    Hornby Stella

    2000-01-01

    Full Text Available Purpose: 1.To determine the anatomical site and underlying causes of severe visual impairment and blindness in children in special education in Andhra Pradesh, India. 2. To compare the causes of blindness in two different regions in the state. 3. To evaluate improvement with correction of refractive error and low-vision devices (LVDs Methods: Children in 6 schools for the blind and in 3 integrated education programmes were examined by one ophthalmologist, and were refracted and assessed for LVDs by an optometrist. The major anatomical site and underlying aetiology of severe visual impairment and blindness (SVI/BL; <6/60 in the better eye were recorded using the standardised WHO reporting form. Results: Two hundred and ninety one students under 16 years were examined, and after refraction, 267 (91.7% were classified as being severely visually impaired or blind. The most common anatomical sites of SVI/BL were retina in 31.1% children; cornea in 24.3%; and whole globe in 20.2%. The aetiology was unknown in 38.2%, hereditary in 34.8% and childhood causes in 24%. 114 children (39.2% had functional low vision (i.e. visual acuity <6/18 to light perception with navigational vision. In this group, 36 children improved with spectacles and 16 benefited by LVDs. 41 children (15.4% were able to read N10 point though they were studying Braille. Conclusion: Overall 37.4% of children had "avoidable" causes of blindness. The major avoidable causes were vitamin-A deficiency and cataract. Vitamin-A deficiency and congenital anomalies were more common in the dry plateau areas of the state. One in seven children could read normal print with optical support.

  7. Air flow phenomena in the model of the blind drift

    Directory of Open Access Journals (Sweden)

    Jaszczur Marek

    2016-01-01

    Full Text Available In the presented paper, Particle Image Velocimetry (PIV has been used to investigate flow pattern and turbulent structure in the model of blind drift. The presented model exist in mining, and has been analyzed to resolve ventilation issues. Blind region is particularly susceptible to unsafe methane accumulation. The measurement system allows us to evaluate all components of the velocity vector in channel cross-section simultaneously. First order and second order statistic of the velocity fields from different channel cross-section are computed and analyzed.

  8. Cortical Plasticity and Olfactory Function in Early Blindness

    Science.gov (United States)

    Araneda, Rodrigo; Renier, Laurent A.; Rombaux, Philippe; Cuevas, Isabel; De Volder, Anne G.

    2016-01-01

    Over the last decade, functional brain imaging has provided insight to the maturation processes and has helped elucidate the pathophysiological mechanisms involved in brain plasticity in the absence of vision. In case of congenital blindness, drastic changes occur within the deafferented “visual” cortex that starts receiving and processing non visual inputs, including olfactory stimuli. This functional reorganization of the occipital cortex gives rise to compensatory perceptual and cognitive mechanisms that help blind persons achieve perceptual tasks, leading to superior olfactory abilities in these subjects. This view receives support from psychophysical testing, volumetric measurements and functional brain imaging studies in humans, which are presented here. PMID:27625596

  9. Blind Recognition Algorithm of Turbo Codes for Communication Intelligence Systems

    OpenAIRE

    Ali Naseri; Omid Azmoon; Samad Fazeli

    2011-01-01

    Turbo codes are widely used in land and space radio communication systems, and because of complexity of structure, are custom in military communication systems. In electronic warfare, COMINT systems make attempt to recognize codes by blind ways. In this Paper, the algorithm is proposed for blind recognition of turbo code parameters like code kind, code-word length, code rate, length of interleaver and delay blocks number of convolution code. The algorithm calculations volume is0.5L3+1.25L, th...

  10. A Robust Algorithm for Blind Total Variation Restoration

    Institute of Scientific and Technical Information of China (English)

    Jing Xu; Qian-shun Chang

    2008-01-01

    Image restoration is a fundamental problem in image processing. Blind image restoration has a great value in its practical application. However, it is not an easy problem to solve due to its complexity and difficulty. In this paper, we combine our robust algorithm for known blur operator with an alternating minimization implicit iterative scheme to deal with blind deconvolution problem, recover the image and identify the point spread function(PSF). The only assumption needed is satisfy the practical physical sense. Numerical experiments demonstrate that this minimization algorithm is efficient and robust over a wide range of PSF and have almost the same results compared with known PSF algorithm.

  11. Preventing diabetic blindness: a priority for South Africa.

    Science.gov (United States)

    Hofman, Karen Joanne; Cook, Colin; Levitt, Naomi

    2014-10-01

    The prevalence of diabetes in South Africa is increasing rapidly, and diabetes is a significant cause of blindness. Diabetic complications can induce a cycle of poverty for affected families. Early detection of retinopathy and appropriate management can prevent blindness. Screening for retinopathy using a mobile retinal camera is highly cost-effective, with costs of screening and follow-up treatment being less than the expense of one year of a disability grant. Such a programme is a prime example of a 'best buy' that should be part of the national diabetes care package. PMID:25363046

  12. Blind Recognition Algorithm of Turbo Codes for Communication Intelligence Systems

    Directory of Open Access Journals (Sweden)

    Ali Naseri

    2011-11-01

    Full Text Available Turbo codes are widely used in land and space radio communication systems, and because of complexity of structure, are custom in military communication systems. In electronic warfare, COMINT systems make attempt to recognize codes by blind ways. In this Paper, the algorithm is proposed for blind recognition of turbo code parameters like code kind, code-word length, code rate, length of interleaver and delay blocks number of convolution code. The algorithm calculations volume is0.5L3+1.25L, therefore it is suitable for real time systems.

  13. Alabama Institute for Deaf and Blind Biodiesel Project Green

    Energy Technology Data Exchange (ETDEWEB)

    Edmiston, Jessica L

    2012-09-28

    Through extensive collaboration, Alabama Institute for Deaf and Blind (AIDB) is Alabama's first educational entity to initiate a biodiesel public education, student training and production program, Project Green. With state and national replication potential, Project Green benefits local businesses and city infrastructures within a 120-mile radius; provides alternative education to Alabama school systems and to schools for the deaf and blind in Appalachian States; trains students with sensory and/or multiple disabilities in the acquisition and production of biodiesel; and educates the external public on alternative fuels benefits.

  14. Neural correlates of virtual route recognition in congenital blindness

    DEFF Research Database (Denmark)

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

    2010-01-01

    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...... participants, the activation pattern strongly resembled the one obtained in the blind when using the TDU. This suggests that in the absence of vision, cross-modal plasticity permits the recruitment of the same cortical network used for spatial navigation tasks in sighted subjects....

  15. Novel blind source separation algorithm using Gaussian mixture density function

    Institute of Scientific and Technical Information of China (English)

    孔薇; 杨杰; 周越

    2004-01-01

    The blind source separation (BSS) is an important task for numerous applications in signal processing, communications and array processing. But for many complex sources blind separation algorithms are not efficient because the probability distribution of the sources cannot be estimated accurately. So in this paper, to justify the ME(maximum enteropy) approach, the relation between the ME and the MMI(minimum mutual information) is elucidated first. Then a novel algorithm that uses Gaussian mixture density to approximate the probability distribution of the sources is presented based on the ME approach. The experiment of the BSS of ship-radiated noise demonstrates that the proposed algorithm is valid and efficient.

  16. An ID-based Blind Signature Scheme from Bilinear Pairings

    OpenAIRE

    B. Umaprasada Rao; K.A.Ajmath

    2010-01-01

    Blind signatures, introduced by Chaum, allow a user to obtain a signature on a message without revealing any thing about the message to the signer. Blind signatures play on important role in plenty of applications such as e-voting, e-cash system where anonymity is of great concern. Identity based(ID-based) public key cryptography can be a good alternative for certified based public key setting, especially when efficient key management and moderate security are required. In this paper, we prop...

  17. A Blind Pilot: Who is a Super-Luminal Observer?

    Directory of Open Access Journals (Sweden)

    Rabounski D.

    2008-04-01

    Full Text Available This paper discusses the nature of a hypothetical super-luminal observer who, as well as a real (sub-light speed observer, perceives the world by light waves. This consideration is due to that fact that the theory of relativity permits different frames of reference, including light-like and super-luminal reference frames. In analogy with a blind pilot on board a supersonic jet aeroplane (or missile, perceived by blind people, it is concluded that the light barrier is observed in the framework of only the light signal exchange experiment.

  18. Engaging blind and partially sighted stakeholders in transformational change.

    Science.gov (United States)

    Pearson, Victoria

    2016-09-01

    For non-profit organizations in the disability sector, engaging stakeholders with disabilities on matters of strategic planning is both a responsibility and an expectation. As part of our current strategic plan, which calls for organizational and systemic transformation, the Canadian National Institute for the Blind (CNIB) has engaged blind and partially sighted stakeholders alongside other interest groups to build and advocate for a more holistic model of vision healthcare and rehabilitation. This article describes the CNIB's multi-year process, including early-stage consultations, collaborative strategy development, and political advocacy and shares our organization's key success factors and learnings in creating meaningful, mutually beneficial engagement. PMID:27576855

  19. Reconstructing the inflaton potential: Perturbative reconstruction to second order

    Energy Technology Data Exchange (ETDEWEB)

    Copeland, Edmund J.; Kolb, Edward W.; Liddle, Andrew R.; Lidsey, James E.

    1993-08-01

    One method to reconstruct the scalar field potential of inflation is a perturbative approach, where the values of the potential and its derivatives are calculated as an expansion in departures from the slow-roll approximation. They can then be expressed in terms of observable quantities, such as the square of the ratio of the gravitational wave amplitude to the density perturbation amplitude, the deviation of the spectral index from the Harrison--Zel'dovich value, etc. Here, we calculate complete expressions for the second-order contributions to the coefficients of the expansion by including for the first time corrections to the standard expressions for the perturbation spectra. As well as offering an improved result, these corrections indicate the expected accuracy of the reconstruction. Typically the corrections are only a few percent.

  20. 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...