Rehabilitation of cortical blindness secondary to stroke.

Science.gov (United States)

Gaber, Tarek A-Z K

2010-01-01

Cortical blindness is a rare complication of posterior circulation stroke. However, its complex presentation with sensory, physical, cognitive and behavioural impairments makes it one of the most challenging. Appropriate approach from a rehabilitation standpoint was never reported. Our study aims to discuss the rehabilitation methods and outcomes of a cohort of patients with cortical blindness. The notes of all patients with cortical blindness referred to a local NHS rehabilitation service in the last 6~years were examined. Patients' demographics, presenting symptoms, scan findings, rehabilitation programmes and outcomes were documented. Seven patients presented to our service, six of them were males. The mean age was 63. Patients 1, 2 and 3 had total blindness with severe cognitive and behavioural impairments, wandering and akathisia. All of them failed to respond to any rehabilitation effort and the focus was on damage limitation. Pharmacological interventions had a modest impact on behaviour and sleep pattern. The 3 patients were discharged to a nursing facility. Patients 4, 5, 6 and 7 had partial blindness with variable severity. All of them suffered from significant memory impairment. However, none suffered from any behavioural, physical or other cognitive impairment. Rehabilitation efforts on 3 patients were carried out collaboratively between brain injury occupational therapists and sensory disability officers. All patients experienced significant improvement in handicap and they all maintained community placements. This small cohort of patients suggests that the rehabilitation philosophy and outcomes of these 2 distinct groups of either total or partial cortical blindness differ significantly.

Exploring Intrinsic and Extrinsic Motivations to Participate in a Crowdsourcing Project to Support Blind and Partially Sighted Students.

Science.gov (United States)

Layas, Fatma; Petrie, Helen

2016-01-01

There have been a number of crowdsourcing projects to support people with disabilities. However, there is little exploration of what motivates people to participate in such crowdsourcing projects. In this study we investigated how different motivational factors can affect the participation of people in a crowdsourcing project to support visually disabled students. We are developing "DescribeIT", a crowdsourcing project to support blind and partially students by having sighted people describe images in digital learning resources. We investigated participants' behavior of the DescribeIT project using three conditions: one intrinsic motivation condition and two extrinsic motivation conditions. The results showed that participants were significantly intrinsically motivated to participate in the DescribeIT project. In addition, participants' intrinsic motivation dominated the effect of the two extrinsic motivational factors in the extrinsic conditions.

Arsanilic acid blindness in pigs

Energy Technology Data Exchange (ETDEWEB)

Menges, R.W.; Kintner, L.D.; Selby, L.A.; Stewart, R.W.; Marlenfeld, C.J.

1970-06-01

Blindness in pigs that were given an overdosage of arsanilic acid is reported. A 0.0375% level of arsanilic acid was fed to 640 pigs for 90 days beginning when the animals were 3 months old. Approximately one month after the start of feeding, partial or complete blindness was observed in 50 of the pigs. Clinical signs, pathologic findings and the chemical analysis of hair are discussed. The level of arsanilic acid used was that recommended for the control of swine dysentery, to be fed for only five or six days. The overdosage resulted from a misunderstanding between the farmer and the feed mill.

Blind Deconvolution of Anisoplanatic Images Collected by a Partially Coherent Imaging System

National Research Council Canada - National Science Library

MacDonald, Adam

2004-01-01

... have limited emissivity or reflectivity. This research proposes a novel blind deconvolution algorithm that is based on a maximum a posteriori Bayesian estimator constructed upon a physically based statistical model for the intensity...

Quantitative assessment of unobserved confounding is mandatory in nonrandomized intervention studies

NARCIS (Netherlands)

Groenwold, R H H; Hak, E; Hoes, A W

OBJECTIVE: In nonrandomized intervention studies unequal distribution of patient characteristics in the groups under study may hinder comparability of prognosis and therefore lead to confounding bias. Our objective was to review methods to control for observed confounding, as well as unobserved

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.

Semi-blind sparse image reconstruction with application to MRFM.

Science.gov (United States)

Park, Se Un; Dobigeon, Nicolas; Hero, Alfred O

2012-09-01

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 algorithm and blind algorithms developed for natural images. We illustrate our myopic algorithm on real MRFM tobacco virus data.

Correction of confounding bias in non-randomized studies by appropriate weighting.

Science.gov (United States)

Schmoor, Claudia; Gall, Christine; Stampf, Susanne; Graf, Erika

2011-03-01

In non-randomized studies, the assessment of a causal effect of treatment or exposure on outcome is hampered by possible confounding. Applying multiple regression models including the effects of treatment and covariates on outcome is the well-known classical approach to adjust for confounding. In recent years other approaches have been promoted. One of them is based on the propensity score and considers the effect of possible confounders on treatment as a relevant criterion for adjustment. Another proposal is based on using an instrumental variable. Here inference relies on a factor, the instrument, which affects treatment but is thought to be otherwise unrelated to outcome, so that it mimics randomization. Each of these approaches can basically be interpreted as a simple reweighting scheme, designed to address confounding. The procedures will be compared with respect to their fundamental properties, namely, which bias they aim to eliminate, which effect they aim to estimate, and which parameter is modelled. We will expand our overview of methods for analysis of non-randomized studies to methods for analysis of randomized controlled trials and show that analyses of both study types may target different effects and different parameters. The considerations will be illustrated using a breast cancer study with a so-called Comprehensive Cohort Study design, including a randomized controlled trial and a non-randomized study in the same patient population as sub-cohorts. This design offers ideal opportunities to discuss and illustrate the properties of the different approaches. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Differential impact of partial cortical blindness on gaze strategies when sitting and walking - an immersive virtual reality study.

Science.gov (United States)

Iorizzo, Dana B; Riley, Meghan E; Hayhoe, Mary; Huxlin, Krystel R

2011-05-25

The present experiments aimed to characterize the visual performance of subjects with long-standing, unilateral cortical blindness when walking in a naturalistic, virtual environment. Under static, seated testing conditions, cortically blind subjects are known to exhibit compensatory eye movement strategies. However, they still complain of significant impairment in visual detection during navigation. To assess whether this is due to a change in compensatory eye movement strategy between sitting and walking, we measured eye and head movements in subjects asked to detect peripherally-presented, moving basketballs. When seated, cortically blind subjects detected ∼80% of balls, while controls detected almost all balls. Seated blind subjects did not make larger head movements than controls, but they consistently biased their fixation distribution towards their blind hemifield. When walking, head movements were similar in the two groups, but the fixation bias decreased to the point that fixation distribution in cortically blind subjects became similar to that in controls - with one major exception: at the time of basketball appearance, walking controls looked primarily at the far ground, in upper quadrants of the virtual field of view; cortically blind subjects looked significantly more at the near ground, in lower quadrants of the virtual field. Cortically blind subjects detected only 58% of the balls when walking while controls detected ∼90%. Thus, the adaptive gaze strategies adopted by cortically blind individuals as a compensation for their visual loss are strongest and most effective when seated and stationary. Walking significantly alters these gaze strategies in a way that seems to favor walking performance, but impairs peripheral target detection. It is possible that this impairment underlies the experienced difficulty of those with cortical blindness when navigating in real life. Copyright © 2011 Elsevier Ltd. All rights reserved.

Nonrandom Intrafraction Target Motions and General Strategy for Correction of Spine Stereotactic Body Radiotherapy

International Nuclear Information System (INIS)

Ma Lijun; Sahgal, Arjun; Hossain, Sabbir; Chuang, Cynthia; Descovich, Martina; Huang, Kim; Gottschalk, Alex; Larson, David A.

2009-01-01

Purpose: To characterize nonrandom intrafraction target motions for spine stereotactic body radiotherapy and to develop a method of correction via image guidance. The dependence of target motions, as well as the effectiveness of the correction strategy for lesions of different locations within the spine, was analyzed. Methods and Materials: Intrafraction target motions for 64 targets in 64 patients treated with a total of 233 fractions were analyzed. Based on the target location, the cases were divided into three groups, i.e., cervical (n = 20 patients), thoracic (n = 20 patients), or lumbar-sacrum (n = 24 patients) lesions. For each case, time-lag autocorrelation analysis was performed for each degree of freedom of motion that included both translations (x, y, and z shifts) and rotations (roll, yaw, and pitch). A general correction strategy based on periodic interventions was derived to determine the time interval required between two adjacent interventions, to overcome the patient-specific target motions. Results: Nonrandom target motions were detected for 100% of cases regardless of target locations. Cervical spine targets were found to possess the highest incidence of nonrandom target motion compared with thoracic and lumbar-sacral lesions (p < 0.001). The average time needed to maintain the target motion to within 1 mm of translation or 1 deg. of rotational deviation was 5.5 min, 5.9 min, and 7.1 min for cervical, thoracic, and lumbar-sacrum locations, respectively (at 95% confidence level). Conclusions: A high incidence of nonrandom intrafraction target motions was found for spine stereotactic body radiotherapy treatments. Periodic interventions at approximately every 5 minutes or less were needed to overcome such motions.

Blind separation of overlapping partials in harmonic musical notes using amplitude and phase reconstruction

Science.gov (United States)

de León, Jesús Ponce; Beltrán, José Ramón

2012-12-01

In this study, a new method of blind audio source separation (BASS) of monaural musical harmonic notes is presented. The input (mixed notes) signal is processed using a flexible analysis and synthesis algorithm (complex wavelet additive synthesis, CWAS), which is based on the complex continuous wavelet transform. When the harmonics from two or more sources overlap in a certain frequency band (or group of bands), a new technique based on amplitude similarity criteria is used to obtain an approximation to the original partial information. The aim is to show that the CWAS algorithm can be a powerful tool in BASS. Compared with other existing techniques, the main advantages of the proposed algorithm are its accuracy in the instantaneous phase estimation, its synthesis capability and that the only input information needed is the mixed signal itself. A set of synthetically mixed monaural isolated notes have been analyzed using this method, in eight different experiments: the same instrument playing two notes within the same octave and two harmonically related notes (5th and 12th intervals), two different musical instruments playing 5th and 12th intervals, two different instruments playing non-harmonic notes, major and minor chords played by the same musical instrument, three different instruments playing non-harmonically related notes and finally the mixture of a inharmonic instrument (piano) and one harmonic instrument. The results obtained show the strength of the technique.

A Novel Therapy for Chronic Sleep-Onset Insomnia: A Retrospective, Nonrandomized Controlled Study of Auto-Adjusting, Dual-Level, Positive Airway Pressure Technology.

Science.gov (United States)

Krakow, Barry; Ulibarri, Victor A; McIver, Natalia D; Nadorff, Michael R

2016-09-29

Evidence indicates that behavioral or drug therapy may not target underlying pathophysiologic mechanisms for chronic insomnia, possibly due to previously unrecognized high rates (30%-90%) of sleep apnea in chronic insomnia patients. Although treatment studies with positive airway pressure (PAP) demonstrate decreased severity of chronic sleep maintenance insomnia in patients with co-occurring sleep apnea, sleep-onset insomnia has not shown similar results. We hypothesized advanced PAP technology would be associated with decreased sleep-onset insomnia severity in a sample of predominantly psychiatric patients with comorbid sleep apnea. We reviewed charts of 74 severe sleep-onset insomnia patients seen from March 2011 to August 2015, all meeting American Academy of Sleep Medicine Work Group criteria for a chronic insomnia disorder and all affirming behavioral and psychological origins for insomnia (averaging 10 of 18 indicators/patient), as well as averaging 2 or more psychiatric symptoms or conditions: depression (65.2%), anxiety (41.9%), traumatic exposure (35.1%), claustrophobia (29.7%), panic attacks (28.4%), and posttraumatic stress disorder (20.3%). All patients failed continuous or bilevel PAP and were manually titrated with auto-adjusting PAP modes (auto-bilevel and adaptive-servo ventilation). At 1-year follow-up, patients were compared through nonrandom assignment on the basis of a PAP compliance metric of > 20 h/wk (56 PAP users) versus insomnia severity (Hedges' g = 1.72) and sleep-onset insomnia (g = 2.07) compared to partial users (g = 1.04 and 0.91, respectively). Both global and sleep-onset insomnia severity decreased below moderate levels in PAP users compared to partial users whose outcomes persisted at moderately severe levels. In a nonrandomized controlled retrospective study, advanced PAP technology (both auto-bilevel and adaptive servo-ventilation) were associated with large decreases in insomnia severity for sleep-onset insomnia patients who

Frugivores bias seed-adult tree associations through nonrandom seed dispersal: a phylogenetic approach.

Science.gov (United States)

Razafindratsima, Onja H; Dunham, Amy E

2016-08-01

Frugivores are the main seed dispersers in many ecosystems, such that behaviorally driven, nonrandom patterns of seed dispersal are a common process; but patterns are poorly understood. Characterizing these patterns may be essential for understanding spatial organization of fruiting trees and drivers of seed-dispersal limitation in biodiverse forests. To address this, we studied resulting spatial associations between dispersed seeds and adult tree neighbors in a diverse rainforest in Madagascar, using a temporal and phylogenetic approach. Data show that by using fruiting trees as seed-dispersal foci, frugivores bias seed dispersal under conspecific adults and under heterospecific trees that share dispersers and fruiting time with the dispersed species. Frugivore-mediated seed dispersal also resulted in nonrandom phylogenetic associations of dispersed seeds with their nearest adult neighbors, in nine out of the 16 months of our study. However, these nonrandom phylogenetic associations fluctuated unpredictably over time, ranging from clustered to overdispersed. The spatial and phylogenetic template of seed dispersal did not translate to similar patterns of association in adult tree neighborhoods, suggesting the importance of post-dispersal processes in structuring plant communities. Results suggest that frugivore-mediated seed dispersal is important for structuring early stages of plant-plant associations, setting the template for post-dispersal processes that influence ultimate patterns of plant recruitment. Importantly, if biased patterns of dispersal are common in other systems, frugivores may promote tree coexistence in biodiverse forests by limiting the frequency and diversity of heterospecific interactions of seeds they disperse. © 2016 by the Ecological Society of America.

Four different ways of philanthropic aid to the blind in medieval eastern Christendom.

Science.gov (United States)

Diamandopoulou-Drummond, A H; Diamandopoulos, A A; Marketos, S G

1995-11-01

The care of the blind, either as medical treatment or as divine therapy, has probably been the most ancient form of help for ill people. However, it was during the Byzantine Empire (325-1453 AD) that the state organized a 'blindness relief' plan as part of a widespread public health system. Our sources for the subject include medical writings, state decrees, Saint's 'vitae' and representations of relevant works of art. Based on the above data we classify the health care for the blind in Byzantium as: (a) support of ophthalmological education as evidenced by an abundance of medical writings on the subject; (b) establishment of charitable institutions exclusively or partially for the blind, where there was not only medical care but also provision for a wide range of social aid - the most advanced being specially trained escorts for each blind person; and (c) support by the state of an extended chain of religious institutions where miraculous help for the blind was promised. We conclude that the public health policy in Byzantium made adequate and very early provision for the blind.

The role of figure-ground segregation in change blindness.

Science.gov (United States)

Landman, Rogier; Spekreijse, Henk; Lamme, Victor A F

2004-04-01

Partial report methods have shown that a large-capacity representation exists for a few hundred milliseconds after a picture has disappeared. However, change blindness studies indicate that very limited information remains available when a changed version of the image is presented subsequently. What happens to the large-capacity representation? New input after the first image may interfere, but this is likely to depend on the characteristics of the new input. In our first experiment, we show that a display containing homogeneous image elements between changing images does not render the large-capacity representation unavailable. Interference occurs when these new elements define objects. On that basis we introduce a new method to produce change blindness: The second experiment shows that change blindness can be induced by redefining figure and background, without an interval between the displays. The local features (line segments) that defined figures and background were swapped, while the contours of the figures remained where they were. Normally, changes are easily detected when there is no interval. However, our paradigm results in massive change blindness. We propose that in a change blindness experiment, there is a large-capacity representation of the original image when it is followed by a homogeneous interval display, but that change blindness occurs whenever the changed image forces resegregation of figures from the background.

The blind leading the blind: use and misuse of blinding in randomized controlled trials.

Science.gov (United States)

Miller, Larry E; Stewart, Morgan E

2011-03-01

The use of blinding strengthens the credibility of randomized controlled trials (RCTs) by minimizing bias. However, there is confusion surrounding the definition of blinding as well as the terms single, double, and triple blind. It has been suggested that these terms should be discontinued due to their broad misinterpretation. We recommend that, instead of abandoning the use of these terms, explicit definitions of blinding should be adopted. We address herein the concept of blinding, propose standard definitions for the consistent use of these terms, and detail when different types of blinding should be utilized. Standardizing the definition of blinding and utilizing proper blinding methods will improve the quality and clarity of reporting in RCTs. Copyright © 2010 Elsevier Inc. All rights reserved.

Non-random distribution of instability-associated chromosomal rearrangement breakpoints in human lymphoblastoid cells

International Nuclear Information System (INIS)

Moore, Stephen R.; Papworth, David; Grosovsky, Andrew J.

2006-01-01

Genomic instability is observed in tumors and in a large fraction of the progeny surviving irradiation. One of the best-characterized phenotypic manifestations of genomic instability is delayed chromosome aberrations. Our working hypothesis for the current study was that if genomic instability is in part attributable to cis mechanisms, we should observe a non-random distribution of chromosomes or sites involved in instability-associated rearrangements, regardless of radiation quality, dose, or trans factor expression. We report here the karyotypic examination of 296 instability-associated chromosomal rearrangement breaksites (IACRB) from 118 unstable TK6 human B lymphoblast, and isogenic derivative, clones. When we tested whether IACRB were distributed across the chromosomes based on target size, a significant non-random distribution was evident (p < 0.00001), and three IACRB hotspots (chromosomes 11, 12, and 22) and one IACRB coldspot (chromosome 2) were identified. Statistical analysis at the chromosomal band-level identified four IACRB hotspots accounting for 20% of all instability-associated breaks, two of which account for over 14% of all IACRB. Further, analysis of independent clones provided evidence within 14 individual clones of IACRB clustering at the chromosomal band level, suggesting a predisposition for further breaks after an initial break at some chromosomal bands. All of these events, independently, or when taken together, were highly unlikely to have occurred by chance (p < 0.000001). These IACRB band-level cluster hotspots were observed independent of radiation quality, dose, or cellular p53 status. The non-random distribution of instability-associated chromosomal rearrangements described here significantly differs from the distribution that was observed in a first-division post-irradiation metaphase analysis (p = 0.0004). Taken together, these results suggest that genomic instability may be in part driven by chromosomal cis mechanisms

Convex blind image deconvolution with inverse filtering

Science.gov (United States)

Lv, Xiao-Guang; Li, Fang; Zeng, Tieyong

2018-03-01

Blind image deconvolution is the process of estimating both the original image and the blur kernel from the degraded image with only partial or no information about degradation and the imaging system. It is a bilinear ill-posed inverse problem corresponding to the direct problem of convolution. Regularization methods are used to handle the ill-posedness of blind deconvolution and get meaningful solutions. In this paper, we investigate a convex regularized inverse filtering method for blind deconvolution of images. We assume that the support region of the blur object is known, as has been done in a few existing works. By studying the inverse filters of signal and image restoration problems, we observe the oscillation structure of the inverse filters. Inspired by the oscillation structure of the inverse filters, we propose to use the star norm to regularize the inverse filter. Meanwhile, we use the total variation to regularize the resulting image obtained by convolving the inverse filter with the degraded image. The proposed minimization model is shown to be convex. We employ the first-order primal-dual method for the solution of the proposed minimization model. Numerical examples for blind image restoration are given to show that the proposed method outperforms some existing methods in terms of peak signal-to-noise ratio (PSNR), structural similarity (SSIM), visual quality and time consumption.

Photogenic partial seizures.

Science.gov (United States)

Hennessy, M J; Binnie, C D

2000-01-01

To establish the incidence and symptoms of partial seizures in a cohort of patients investigated on account of known sensitivity to intermittent photic stimulation and/or precipitation of seizures by environmental visual stimuli such as television (TV) screens or computer monitors. We report 43 consecutive patients with epilepsy, who had exhibited a significant EEG photoparoxysmal response or who had seizures precipitated by environmental visual stimuli and underwent detailed assessment of their photosensitivity in the EEG laboratory, during which all were questioned concerning their ictal symptoms. All patients were considered on clinical grounds to have an idiopathic epilepsy syndrome. Twenty-eight (65%) patients reported visually precipitated attacks occurring initially with maintained consciousness, in some instances evolving to a period of confusion or to a secondarily generalized seizure. Visual symptoms were most commonly reported and included positive symptoms such as coloured circles or spots, but also blindness and subjective symptoms such as "eyes going funny." Other symptoms described included nonspecific cephalic sensations, deja-vu, auditory hallucinations, nausea, and vomiting. No patient reported any clear spontaneous partial seizures, and there were no grounds for supposing that any had partial epilepsy excepting the ictal phenomenology of some or all of the visually induced attacks. These findings provide clinical support for the physiological studies that indicate that the trigger mechanism for human photosensitivity involves binocularly innervated cells located in the visual cortex. Thus the visual cortex is the seat of the primary epileptogenic process, and the photically triggered discharges and seizures may be regarded as partial with secondary generalization.

What makes an automated teller machine usable by blind users?

Science.gov (United States)

Manzke, J M; Egan, D H; Felix, D; Krueger, H

1998-07-01

Fifteen blind and sighted subjects, who featured as a control group for acceptance, were asked for their requirements for automated teller machines (ATMs). Both groups also tested the usability of a partially operational ATM mock-up. This machine was based on an existing cash dispenser, providing natural speech output, different function menus and different key arrangements. Performance and subjective evaluation data of blind and sighted subjects were collected. All blind subjects were able to operate the ATM successfully. The implemented speech output was the main usability factor for them. The different interface designs did not significantly affect performance and subjective evaluation. Nevertheless, design recommendations can be derived from the requirement assessment. The sighted subjects were rather open for design modifications, especially the implementation of speech output. However, there was also a mismatch of the requirements of the two subject groups, mainly concerning the key arrangement.

Variation of mutational burden in healthy human tissues suggests non-random strand segregation and allows measuring somatic mutation rates.

Science.gov (United States)

Werner, Benjamin; Sottoriva, Andrea

2018-06-01

The immortal strand hypothesis poses that stem cells could produce differentiated progeny while conserving the original template strand, thus avoiding accumulating somatic mutations. However, quantitating the extent of non-random DNA strand segregation in human stem cells remains difficult in vivo. Here we show that the change of the mean and variance of the mutational burden with age in healthy human tissues allows estimating strand segregation probabilities and somatic mutation rates. We analysed deep sequencing data from healthy human colon, small intestine, liver, skin and brain. We found highly effective non-random DNA strand segregation in all adult tissues (mean strand segregation probability: 0.98, standard error bounds (0.97,0.99)). In contrast, non-random strand segregation efficiency is reduced to 0.87 (0.78,0.88) in neural tissue during early development, suggesting stem cell pool expansions due to symmetric self-renewal. Healthy somatic mutation rates differed across tissue types, ranging from 3.5 × 10-9/bp/division in small intestine to 1.6 × 10-7/bp/division in skin.

Variation of mutational burden in healthy human tissues suggests non-random strand segregation and allows measuring somatic mutation rates.

Directory of Open Access Journals (Sweden)

Benjamin Werner

2018-06-01

Full Text Available The immortal strand hypothesis poses that stem cells could produce differentiated progeny while conserving the original template strand, thus avoiding accumulating somatic mutations. However, quantitating the extent of non-random DNA strand segregation in human stem cells remains difficult in vivo. Here we show that the change of the mean and variance of the mutational burden with age in healthy human tissues allows estimating strand segregation probabilities and somatic mutation rates. We analysed deep sequencing data from healthy human colon, small intestine, liver, skin and brain. We found highly effective non-random DNA strand segregation in all adult tissues (mean strand segregation probability: 0.98, standard error bounds (0.97,0.99. In contrast, non-random strand segregation efficiency is reduced to 0.87 (0.78,0.88 in neural tissue during early development, suggesting stem cell pool expansions due to symmetric self-renewal. Healthy somatic mutation rates differed across tissue types, ranging from 3.5 × 10-9/bp/division in small intestine to 1.6 × 10-7/bp/division in skin.

Socio-Emotional Effects of the Transition from Sight to Blindness

Science.gov (United States)

Thurston, Mhairi; Thurston, Allen; McLeod, John

2010-01-01

The research examined the socio-emotional impact of sight loss on a sample of 18 blind and partially sighted adults from the east coast of Scotland (average age 64). The impact of sight loss in four core areas (mood, self-concept, social connectedness and loss) was explored. Data were collected using the mental health and social functioning…

A systematic review of nonrandomized controlled trials on the curative effects of aquatic exercise

Directory of Open Access Journals (Sweden)

Kamioka H

2011-03-01

Full Text Available Hiroharu Kamioka1, Kiichiro Tsutani2, Yoshiteru Mutoh3, Hiroyasu Okuizum4, Miho Ohta5, Shuichi Handa4, Shinpei Okada6, Jun Kitayuguchi7, Masamitsu Kamada7, Nobuyoshi Shiozawa8, Sang-Jun Park4, Takuya Honda4, Shoko Moriyama41Faculty of Regional Environment Science, Tokyo University of Agriculture, Tokyo, Japan; 2Department of Drug Policy and Management, Graduate School of Pharmaceutical Sciences, 3Department of Physical and Health Education, Graduate School of Education, The University of Tokyo, Tokyo, Japan; 4Mimaki Onsen (Spa Clinic, Tomi City, Japan; 5Laboratory of Aqua, Health, and Sports Medicine, 6Physical Education and Medicine Research Foundation, Nagano, Japan; 7Physical Education and Medicine Research Center Unnan, Unnan City, Japan; 8Department of Longevity and Social Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, JapanBackground: The objectives of this review were to integrate the evidence of curative effects through aquatic exercise and assess the quality of studies based on a review of nonrandomized controlled trials (nRCTs.Methods: Study design was a systematic review of nonrandomized controlled trials. Trials were eligible if they were nonrandomized clinical trials. Studies included one treatment group in which aquatic exercise was applied. We searched the following databases from 2000 up to July 20, 2009: MEDLINE via PubMed, CINAHL, and Ichushi-Web.Results: Twenty-one trials met all inclusion criteria. Languages included were English (N = 9, Japanese (N = 11, and Korean (N = 1. Target diseases were knee and/or hip osteoarthritis, poliomyelitis, chronic kidney disease, discomforts of pregnancy, cardiovascular diseases, and rotator cuff tears. Many studies on nonspecific disease (healthy participants were included. All studies reported significant effectiveness in at least one or more outcomes. However results of evaluations with the TREND and CLEAR-NPT checklists generally

Neuromuscular Exercise Post Partial Medial Meniscectomy

DEFF Research Database (Denmark)

Hall, Michelle; Hinman, Rana S; Wrigley, Tim V

2015-01-01

PURPOSE: To evaluate the effects of a 12-week, home-based, physiotherapist-guided neuromuscular exercise program on the knee adduction moment (an indicator of mediolateral knee load distribution) in people with a medial arthroscopic partial meniscectomy within the past 3-12 months. METHODS......: An assessor-blinded, randomised controlled trial including people aged 30-50 years with no to mild pain following medial arthroscopic partial meniscectomy was conducted. Participants were randomly allocated to either a 12-week neuromuscular exercise program that targeted neutral lower limb alignment...... or a control group with no exercise. The exercise program included eight individual sessions with one of seven physiotherapists in private clinics, together with home exercises. Primary outcomes were the peak external knee adduction moment during normal pace walking and during a one-leg sit-to-stand. Secondary...

Effect of Nigella sativa supplementation over a one-year period on lipid levels, blood pressure and heart rate in type-2 diabetic patients receiving oral hypoglycemic agents: nonrandomized clinical trial.

Science.gov (United States)

Badar, Ahmed; Kaatabi, Huda; Bamosa, Abdullah; Al-Elq, Abdulmohsen; Abou-Hozaifa, Bodour; Lebda, Fatma; Alkhadra, Akram; Al-Almaie, Sameeh

2017-01-01

Diabetic patients with hypertension and dyslipidemia are at a high risk of cardiovascular complications. To determine the effect of Nigella sativa supplementation on the lipid profile, mean arterial pressure, and heart rate in persons with type 2 diabetes on oral hypoglycemic agents (OHA). Single-blind, nonrandomized. Diabetes clinic of a university hospital in Saudi Arabia. Type-2 diabetic patients were recruited by purposive sampling and assigned to treatment or control at the discretion of the investigator with the patient blinded to treatment. Before the in.tervention and every 3 months thereafter until the end of the treatment period, the following parameters were measured: triglycerides (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR), and body mass index (BMI). Results at the baseline and each subsequent visit were compared between the two groups. Lipid and cardiovascular parameters, and BMI. Fifty-seven patients were assigned to receive N sativa 2 g daily for one year and 57 were assigned to receive an identical regimen of placebo, along with OHA. A significant decrease in HDL-C and increase in the TC/HDL-C and LDL-C/HDL-C ratios were seen in the control group. The N sativa group had a signifi.cant decline in TC, LDL-C, TC/HDL-C and LDL-C/HDL-C ratios, compared with the respective baseline data and the control group. HDL-C was significantly elevated in the N sativa group. The control group showed a significant elevation in MAP. The N sativa group had a significant reduction in SBP, DBP, MAP and HR and a significant decrease in DBP, MAP and HR as compared with the control group. N sativa supplementation improves total cholesterol, mean arterial pressure and heart rate in type 2 diabetes patients on oral hypoglycemic agents. There were 9 subjects in each group lost to follow up

A Novel Partial Discharge Ultra-High Frequency Signal De-Noising Method Based on a Single-Channel Blind Source Separation Algorithm

Directory of Open Access Journals (Sweden)

Liangliang Wei

2018-02-01

Full Text Available To effectively de-noise the Gaussian white noise and periodic narrow-band interference in the background noise of partial discharge ultra-high frequency (PD UHF signals in field tests, a novel de-noising method, based on a single-channel blind source separation algorithm, is proposed. Compared with traditional methods, the proposed method can effectively de-noise the noise interference, and the distortion of the de-noising PD signal is smaller. Firstly, the PD UHF signal is time-frequency analyzed by S-transform to obtain the number of source signals. Then, the single-channel detected PD signal is converted into multi-channel signals by singular value decomposition (SVD, and background noise is separated from multi-channel PD UHF signals by the joint approximate diagonalization of eigen-matrix method. At last, the source PD signal is estimated and recovered by the l1-norm minimization method. The proposed de-noising method was applied on the simulation test and field test detected signals, and the de-noising performance of the different methods was compared. The simulation and field test results demonstrate the effectiveness and correctness of the proposed method.

Tests for nonrandomness in quantum jumps

International Nuclear Information System (INIS)

Berkeland, D.J.; Raymondson, D.A.; Tassin, V.M.

2004-01-01

In a fundamental test of quantum mechanics, we have observed 228 000 quantum jumps of a single trapped and laser cooled 88 Sr + ion. This represents a statistical increase of two orders of magnitude over previous similar analyses of quantum jumps. Compared to other searches for nonrandomness in quantum-mechanical processes, using quantum jumps simplifies the interpretation of data by eliminated multiparticle effects and providing near-unit detection efficiency of transitions. We measure the fractional reduction in the entropy of information to be -4 when the value of any interval between quantum jumps is known. We also find that the number of runs of successively increasing or decreasing interval times agrees with the theoretically expected values. Furthermore, we analyze 238 000 quantum jumps from two simultaneously confined ions and find that the number of apparently coincidental transitions is as expected. Finally, we observe 8400 spontaneous decays of two simultaneously trapped ions and find that the number of apparently coincidental decays from the metastable state agrees with the expected value. We find no evidence for short- or long-term correlations in the intervals of the quantum jumps or in the decay of the quantum states, in agreement with quantum theory

Blind Quantum Signature with Blind Quantum Computation

Science.gov (United States)

Li, Wei; Shi, Ronghua; Guo, Ying

2017-04-01

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

The review of the organization of library services for the blind and partially sighted in the selected countries

Directory of Open Access Journals (Sweden)

Damjana Vovk

2011-01-01

Full Text Available Purpose: Models of organization of library services for the blind and partially sighted from the view of special and public librarianship in selected countries were examined.In addition, theoretical and legislative frameworks, professional guidelines and trends are explored. Some terminological inconsistencies and obstacles in performing the services are also presented.Methodology/approach: The explorative-comparative study carried in the years 2008-2010 includes the comparative analysis of data acquired by the survey and literature desktop research. The research sample included 14 countries - eleven European countries, USA,Australia, and Canada.Results: The findings show great varieties among the selected countries, however,there is the trend of moving the organization of services based on a private charitable association to the formalized state supported system. The majority of countries have applied the centralized model with one specialized (national library. There is rarely a case of formal inclusion of public libraries in the organization of services. Recent major professional interests in the field of providing library services to visually impaired are broadening the copyright exceptions and user groups, and the implementation of information technology for bigger production of alternative formats and availability of library materials.Research limitation: The low rate of survey response and the differences in the organization of library services influenced on the lack of data and low level of data comparability.Originality/practical implications: The results are useful for designing a model of library services in Slovenia.

Non-random mating and convergence over time for alcohol consumption, smoking, and exercise: the Nord-Trøndelag Health Study.

Science.gov (United States)

Ask, Helga; Rognmo, Kamilla; Torvik, Fartein Ask; Røysamb, Espen; Tambs, Kristian

2012-05-01

Spouses tend to have similar lifestyles. We explored the degree to which spouse similarity in alcohol use, smoking, and physical exercise is caused by non-random mating or convergence. We used data collected for the Nord-Trøndelag Health Study from 1984 to 1986 and prospective registry information about when and with whom people entered marriage/cohabitation between 1970 and 2000. Our sample included 19,599 married/cohabitating couples and 1,551 future couples that were to marry/cohabitate in the 14-16 years following data collection. All couples were grouped according to the duration between data collection and entering into marriage/cohabitation. Age-adjusted polychoric spouse correlations were used as the dependent variables in non-linear segmented regression analysis; the independent variable was time. The results indicate that spouse concordance in lifestyle is due to both non-random mating and convergence. Non-random mating appeared to be strongest for smoking. Convergence in alcohol use and smoking was evident during the period prior to marriage/cohabitation, whereas convergence in exercise was evident throughout life. Reduced spouse similarity in smoking with relationship duration may reflect secular trends.

POSTERIOR SEGMENT CAUSES OF BLINDNESS AMONG CHILDREN IN BLIND SCHOOLS

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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

Partial recovery of visual-spatial remapping of touch after restoring vision in a congenitally blind man.

Science.gov (United States)

Ley, Pia; Bottari, Davide; Shenoy, Bhamy H; Kekunnaya, Ramesh; Röder, Brigitte

2013-05-01

In an initial processing step, sensory events are encoded in modality specific representations in the brain but seem to be automatically remapped into a supra-modal, presumably visual-external frame of reference. To test whether there is a sensitive phase in the first years of life during which visual input is crucial for the acquisition of this remapping process, we tested a single case of a congenitally blind man whose sight was restored after the age of two years. HS performed a tactile temporal order judgment task (TOJ) which required judging the temporal order of two tactile stimuli, one presented to each index finger. In addition, a visual-tactile cross-modal congruency task was run, in which spatially congruent and spatially incongruent visual distractor stimuli were presented together with tactile stimuli. The tactile stimuli had to be localized. Both tasks were performed with an uncrossed and a crossed hand posture. Similar to congenitally blind individuals HS did not show a crossing effect in the tactile TOJ task suggesting an anatomical rather than visual-external coding of touch. In the visual-tactile task, however, external remapping of touch was observed though incomplete compared to sighted controls. These data support the hypothesis of a sensitive phase for the acquisition of an automatic use of visual-spatial representations for coding tactile input. Nonetheless, these representations seem to be acquired to some extent after the end of congenital blindness but seem to be recruited only in the context of visual stimuli and are used with a reduced efficiency. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Ability to Assume the Upright Position in Blind and Sighted Children.

Science.gov (United States)

Gipsman, Sandra Curtis

To investigate the ability of 48 blind and partially sighted children (8 to 10 and 12 to 14 years old) to assume the upright position, Ss were given six trials in which they were requested to move themselves from a tilted starting position in a specially constructed chair to an upright position. No significant differences were found between three…

Statistical method on nonrandom clustering with application to somatic mutations in cancer

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Rejto Paul A

2010-01-01

Full Text Available Abstract Background Human cancer is caused by the accumulation of tumor-specific mutations in oncogenes and tumor suppressors that confer a selective growth advantage to cells. As a consequence of genomic instability and high levels of proliferation, many passenger mutations that do not contribute to the cancer phenotype arise alongside mutations that drive oncogenesis. While several approaches have been developed to separate driver mutations from passengers, few approaches can specifically identify activating driver mutations in oncogenes, which are more amenable for pharmacological intervention. Results We propose a new statistical method for detecting activating mutations in cancer by identifying nonrandom clusters of amino acid mutations in protein sequences. A probability model is derived using order statistics assuming that the location of amino acid mutations on a protein follows a uniform distribution. Our statistical measure is the differences between pair-wise order statistics, which is equivalent to the size of an amino acid mutation cluster, and the probabilities are derived from exact and approximate distributions of the statistical measure. Using data in the Catalog of Somatic Mutations in Cancer (COSMIC database, we have demonstrated that our method detects well-known clusters of activating mutations in KRAS, BRAF, PI3K, and β-catenin. The method can also identify new cancer targets as well as gain-of-function mutations in tumor suppressors. Conclusions Our proposed method is useful to discover activating driver mutations in cancer by identifying nonrandom clusters of somatic amino acid mutations in protein sequences.

What is Color Blindness?

Science.gov (United States)

... Color Blindness? Who Is at Risk for Color Blindness? Color Blindness Causes Color Blindness Diagnosis and Treatment How Color Blindness Is Tested What Is Color Blindness? Leer en Español: ¿Qué es el daltonismo? Written ...

The Effects of the Bali Yoga Program for Breast Cancer Patients on Chemotherapy-Induced Nausea and Vomiting: Results of a Partially Randomized and Blinded Controlled Trial.

Science.gov (United States)

Anestin, Annélie S; Dupuis, Gilles; Lanctôt, Dominique; Bali, Madan

2017-10-01

Complementary and alternative medicine has been shown to be beneficial in reducing chemotherapy-induced nausea and vomiting. However, conclusive results are lacking in order to confirm its usefulness. The purpose of this study was to determine whether a standardized yoga intervention could reduce these adverse symptoms. This was a partially randomized and blinded controlled trial comparing a standardized yoga intervention with standard care. Eligible patients were adults diagnosed with stages I to III breast cancer receiving chemotherapy. Patients randomized to the experimental group participated in an 8-week yoga program. There was no significant difference between the experimental and control groups on chemotherapy-induced nausea and vomiting after 8 weeks. Results suggest the yoga program is not beneficial in managing these adverse symptoms. However, considering preliminary evidence suggesting yoga's beneficial impact in cancer symptom management, methodological limitations should be explored and additional studies should be conducted.

Comparison of blind imaging performance of Fizeau and Michelson type arrays for a partially resolved object

NARCIS (Netherlands)

Van der Avoort, C.; Den Herder, J.W.; Braat, J.

2005-01-01

This paper compares two well-known types of interferometer arrays for optical aperture synthesis. An analytical model for both types describes the expected output, in terms of photon counts. The goal is to characterize the performance of both types of array for blind imaging of a wide-field or

Effectiveness of yoga program in the management of diabetes using community health workers in the urban slums of Bangalore city: A non-randomized controlled trial

Science.gov (United States)

Dasappa, Hemavathi; Fathima, Farah Naaz; Prabhakar, Rugmani

2016-01-01

Trial Design: Nonrandomized controlled trial. Methods: Nonrandomized controlled trial. This was an interventional study that was conducted in 4 slums of Bengaluru. Of the 256 diabetes participants, only 109 people agreed to participate in the program. Of 109 people, 52 people agreed to participate in the intervention (agreed to learn and practice Yoga) while the remaining 57 people were assigned to nonintervention group. Randomization and blinding could not be done. Objective and Outcome: The study was conducted with objective of assessing the effectiveness of Yoga, Pranayama, and Sudarshan Kriya in the community-based management of diabetes mellitus. The primary outcome variable was Hb1Ac and secondary outcome variables were systolic blood pressure (SBP), diastolic blood pressure (DBP), adherence to medication, and changes in lifestyle. Results: The study was conducted for 40 days. Community health workers made a total of 6 visits during the study. All the 109 participants were available for weekly follow-up. There were no drop outs among the study population. Statistically significant change was seen in the consumption of vegetable (χ2 = 15.326, P < 0.005), fruits (χ2 = 16.207, P < 0.005), salty food (χ2 = 14.823, P < 0.005), bakery food (χ2 = 10.429, P < 0.005) and fried food (χ2 = 15.470, P < 0.005), adherence to metformin (χ2 = 41.780, P < 0.005) and other medication(χ2 = 21.871, P < 0.005) and proportion of patients with DBP under control (χ2 = 9.396, P < 0.005) and proportion of people with glucose random blood sugar under control (χ2 = 29.693, P < 0.005) between the two groups following the intervention. Statistically significant change was also seen in the proportion of people with SBP/DBP ≤140/90 (χ2 = 10.635, P < 0.005) between the two groups. Conclusion: The Yoga program was successful in improving dietary practices and medication adherence and in increasing the proportion of diabetics and hypertensive patients under control. PMID:28217594

Effectiveness of yoga program in the management of diabetes using community health workers in the urban slums of Bangalore city: A non-randomized controlled trial

Directory of Open Access Journals (Sweden)

Hemavathi Dasappa

2016-01-01

Full Text Available Trial Design: Nonrandomized controlled trial. Methods: Nonrandomized controlled trial. This was an interventional study that was conducted in 4 slums of Bengaluru . Of the 256 diabetes participants, only 109 people agreed to participate in the program. Of 109 people, 52 people agreed to participate in the intervention (agreed to learn and practice Yoga while the remaining 57 people were assigned to nonintervention group. Randomization and blinding could not be done. Objective and Outcome: The study was conducted with objective of assessing the effectiveness of Yoga, Pranayama, and Sudarshan Kriya in the community-based management of diabetes mellitus. The primary outcome variable was Hb1Ac and secondary outcome variables were systolic blood pressure (SBP, diastolic blood pressure (DBP, adherence to medication, and changes in lifestyle. Results: The study was conducted for 40 days. Community health workers made a total of 6 visits during the study. All the 109 participants were available for weekly follow-up. There were no drop outs among the study population. Statistically significant change was seen in the consumption of vegetable (c2 = 15.326, P < 0.005, fruits (c2 = 16.207, P < 0.005, salty food (c2 = 14.823, P < 0.005, bakery food (c2 = 10.429, P < 0.005 and fried food (c2 = 15.470, P < 0.005, adherence to metformin (c2 = 41.780, P < 0.005 and other medication(c2 = 21.871, P < 0.005 and proportion of patients with DBP under control (c2 = 9.396, P < 0.005 and proportion of people with glucose random blood sugar under control (c2 = 29.693, P < 0.005 between the two groups following the intervention. Statistically significant change was also seen in the proportion of people with SBP/DBP ≤140/90 (c2 = 10.635, P < 0.005 between the two groups. Conclusion: The Yoga program was successful in improving dietary practices and medication adherence and in increasing the proportion of diabetics and hypertensive patients under control.

Blindness caused by cosmetic filler injection: a review of cause and therapy.

Science.gov (United States)

Carruthers, Jean D A; Fagien, Steve; Rohrich, Rod J; Weinkle, Susan; Carruthers, Alastair

2014-12-01

Vascular occlusion causing blindness is a rare yet greatly feared complication of the use of facial aesthetic fillers. The authors performed a review of the aesthetic literature to ascertain the reported cases of blindness and the literature reporting variations in the vascular anatomy of the human face. The authors suggest a small but potentially helpful addition to the accepted management of the acute case. Cases of blindness, mostly irreversible, from aesthetic filler injections have been reported from Asia, Europe, and North America. Autologous fat appears to be the most frequent filler causing blindness. Some cases of partial visual recovery have been reported with hyaluronic acid and calcium hydroxylapatite fillers. The sudden profusion of new medical and nonmedical aesthetic filler injectors raises a new cause for alarm about patient safety. The published reports in the medical literature are made by experienced aesthetic surgeons and thus the actual incidence may be even higher. Also, newer injectors may not be aware of the variations in the pattern of facial vascular arborization. The authors present a summary of the relevant literature to date and a suggested helpful addition to the protocols for urgent management.

Network meta-analysis incorporating randomized controlled trials and non-randomized comparative cohort studies for assessing the safety and effectiveness of medical treatments: challenges and opportunities

OpenAIRE

Cameron, Chris; Fireman, Bruce; Hutton, Brian; Clifford, Tammy; Coyle, Doug; Wells, George; Dormuth, Colin R.; Platt, Robert; Toh, Sengwee

2015-01-01

Network meta-analysis is increasingly used to allow comparison of multiple treatment alternatives simultaneously, some of which may not have been compared directly in primary research studies. The majority of network meta-analyses published to date have incorporated data from randomized controlled trials (RCTs) only; however, inclusion of non-randomized studies may sometimes be considered. Non-randomized studies can complement RCTs or address some of their limitations, such as short follow-up...

Causes of blindness in blind unit of the school for the handicapped ...

African Journals Online (AJOL)

To describe the causes of blindness in pupils and staff in the blind unit of the School for the Handicapped in Kwara State. 2. To identify problems in the blind school and initiate intervention. All the blind or visually challenged people in the blind unit of the school for the handicapped were interviewed and examined using a ...

Partially converted stereoscopic images and the effects on visual attention and memory

Science.gov (United States)

Kim, Sanghyun; Morikawa, Hiroyuki; Mitsuya, Reiko; Kawai, Takashi; Watanabe, Katsumi

2015-03-01

This study contained two experimental examinations of the cognitive activities such as visual attention and memory in viewing stereoscopic (3D) images. For this study, partially converted 3D images were used with binocular parallax added to a specific region of the image. In Experiment 1, change blindness was used as a presented stimulus. The visual attention and impact on memory were investigated by measuring the response time to accomplish the given task. In the change blindness task, an 80 ms blank was intersected between the original and altered images, and the two images were presented alternatingly for 240 ms each. Subjects were asked to temporarily memorize the two switching images and to compare them, visually recognizing the difference between the two. The stimuli for four conditions (2D, 3D, Partially converted 3D, distracted partially converted 3D) were randomly displayed for 20 subjects. The results of Experiment 1 showed that partially converted 3D images tend to attract visual attention and are prone to remain in viewer's memory in the area where moderate negative parallax has been added. In order to examine the impact of a dynamic binocular disparity on partially converted 3D images, an evaluation experiment was conducted that applied learning, distraction, and recognition tasks for 33 subjects. The learning task involved memorizing the location of cells in a 5 × 5 matrix pattern using two different colors. Two cells were positioned with alternating colors, and one of the gray cells was moved up, down, left, or right by one cell width. Experimental conditions was set as a partially converted 3D condition in which a gray cell moved diagonally for a certain period of time with a dynamic binocular disparity added, a 3D condition in which binocular disparity was added to all gray cells, and a 2D condition. The correct response rates for recognition of each task after the distraction task were compared. The results of Experiment 2 showed that the correct

Representing vision and blindness.

Science.gov (United States)

Ray, Patrick L; Cox, Alexander P; Jensen, Mark; Allen, Travis; Duncan, William; Diehl, Alexander D

2016-01-01

There have been relatively few attempts to represent vision or blindness ontologically. This is unsurprising as the related phenomena of sight and blindness are difficult to represent ontologically for a variety of reasons. Blindness has escaped ontological capture at least in part because: blindness or the employment of the term 'blindness' seems to vary from context to context, blindness can present in a myriad of types and degrees, and there is no precedent for representing complex phenomena such as blindness. We explore current attempts to represent vision or blindness, and show how these attempts fail at representing subtypes of blindness (viz., color blindness, flash blindness, and inattentional blindness). We examine the results found through a review of current attempts and identify where they have failed. By analyzing our test cases of different types of blindness along with the strengths and weaknesses of previous attempts, we have identified the general features of blindness and vision. We propose an ontological solution to represent vision and blindness, which capitalizes on resources afforded to one who utilizes the Basic Formal Ontology as an upper-level ontology. The solution we propose here involves specifying the trigger conditions of a disposition as well as the processes that realize that disposition. Once these are specified we can characterize vision as a function that is realized by certain (in this case) biological processes under a range of triggering conditions. When the range of conditions under which the processes can be realized are reduced beyond a certain threshold, we are able to say that blindness is present. We characterize vision as a function that is realized as a seeing process and blindness as a reduction in the conditions under which the sight function is realized. This solution is desirable because it leverages current features of a major upper-level ontology, accurately captures the phenomenon of blindness, and can be

Adapting smart phone applications about physics education to blind students

Science.gov (United States)

Bülbül, M. Ş.; Yiğit, N.; Garip, B.

2016-04-01

Today, most of necessary equipment in a physics laboratory are available for smartphone users via applications. Physics teachers may measure from acceleration to sound volume with its internal sensors. These sensors collect data and smartphone applications make the raw data visible. Teachers who do not have well-equipped laboratories at their schools may have an opportunity to conduct experiments with the help of smart phones. In this study, we analyzed possible open source physics education applications in terms of blind users in inclusive learning environments. All apps are categorized as partially, full or non-supported. The roles of blind learner’s friend during the application are categorized as reader, describer or user. Mentioned apps in the study are compared with additional opportunities like size and downloading rates. Out of using apps we may also get information about whether via internet and some other extra information for different experiments in physics lab. Q-codes reading or augmented reality are two other opportunity provided by smart phones for users in physics labs. We also summarized blind learner’s smartphone experiences from literature and listed some suggestions for application designers about concepts in physics.

Navigation Problems in Blind-to-Blind Pedestrians Tele-assistance Navigation

OpenAIRE

Balata , Jan; Mikovec , Zdenek; Maly , Ivo

2015-01-01

International audience; We raise a question whether it is possible to build a large-scale navigation system for blind pedestrians where a blind person navigates another blind person remotely by mobile phone. We have conducted an experiment, in which we observed blind people navigating each other in a city center in 19 sessions. We focused on problems in the navigator’s attempts to direct the traveler to the destination. We observed 96 problems in total, classified them on the basis of the typ...

Double-Blinding and Bias in Medication and Cognitive-Behavioral Therapy Trials for Major Depressive Disorder [version 1; referees: 2 approved

Directory of Open Access Journals (Sweden)

Douglas Berger

2015-08-01

Full Text Available While double-blinding is a crucial aspect of study design in an interventional clinical trial of medication for a disorder with subjective endpoints such as major depressive disorder, psychotherapy clinical trials, particularly cognitive-behavioral therapy trials, cannot be double-blinded. This paper highlights the evidence-based medicine problem of double-blinding in the outcome research of a psychotherapy and opines that psychotherapy clinical trials should be called, “partially-controlled clinical data” because they are not double-blinded. The implications for practice are, 1. For practitioners to be clear with patients the level of rigor to which interventions have been studied, 2. For authors of psychotherapy outcome studies to be clear that the problem in the inability to blind a psychotherapy trial severely restricts the validity of any conclusions that can be drawn, and 3. To petition National Health Insurance plans to use caution in approving interventions studied without double-blinded confirmatory trials as they may lead patients to avoid other treatments shown to be effective in double-blinded trials.

Run charts revisited: a simulation study of run chart rules for detection of non-random variation in health care processes.

Science.gov (United States)

Anhøj, Jacob; Olesen, Anne Vingaard

2014-01-01

A run chart is a line graph of a measure plotted over time with the median as a horizontal line. The main purpose of the run chart is to identify process improvement or degradation, which may be detected by statistical tests for non-random patterns in the data sequence. We studied the sensitivity to shifts and linear drifts in simulated processes using the shift, crossings and trend rules for detecting non-random variation in run charts. The shift and crossings rules are effective in detecting shifts and drifts in process centre over time while keeping the false signal rate constant around 5% and independent of the number of data points in the chart. The trend rule is virtually useless for detection of linear drift over time, the purpose it was intended for.

Monotherapy for partial epilepsy: focus on levetiracetam

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Antonio Gambardella

2008-03-01

Full Text Available Antonio Gambardella1,2, Angelo Labate1,2, Eleonora Colosimo1, Roberta Ambrosio1, Aldo Quattrone1,21Institute of Neurology, University Magna Græcia, Catanzaro, Italy; 2Institute of Neurological Sciences, National Research Council, Piano Lago di Mangone, Cosenza, ItalyAbstract: Levetiracetam (LEV, the S-enantiomer of alpha-ethyl-2-oxo-1-pyrollidine acetamide, is a recently licensed antiepileptic drug (AED for adjunctive therapy of partial seizures. Its mechanism of action is uncertain but it exhibits a unique profile of anticonvulsant activity in models of chronic epilepsy. Five randomized, double-blind, placebo-controlled trials enrolling adult or pediatric patients with refractory partial epilepsy have demonstrated the efficacy of LEV as adjunctive therapy, with a responder rate (≥50% reduction in seizure frequency of 28%–45%. Long-term efficacy studies suggest retention rates of 60% after one year, with 13% of patients seizure-free for 6 months of the study and 8% seizure-free for 1 year. More recent studies illustrated successful conversion to monotherapy in patients with refractory epilepsy, and its effectiveness as a single agent in partial epilepsy. LEV has also efficacy in generalized epilepsies. Adverse effects of LEV, including somnolence, lethargy, and dizziness, are generally mild and their occurrence rate seems to be not significantly different from that observed in placebo groups. LEV also has no clinically significant pharmacokinetic interactions with other AEDs, or with commonly prescribed medications. The combination of effective antiepileptic properties with a relatively mild adverse effect profile makes LEV an attractive therapy for partial seizures.Keywords: levetiracetam, partial epilepsy, antiepileptic drugs

Per-Oral Endoscopic Myotomy Versus Laparoscopic Heller Myotomy for Achalasia: A Meta-Analysis of Nonrandomized Comparative Studies.

Science.gov (United States)

Zhang, Yuan; Wang, Hongjuan; Chen, Xingdong; Liu, Lan; Wang, Hongbo; Liu, Bin; Guo, Jianqiang; Jia, Hongying

2016-02-01

We aimed to assess the short-term outcomes of per-oral endoscopic myotomy (POEM) compared with laparoscopic Heller myotomy (LHM) for achalasia through a meta-analysis of nonrandomized comparative studies.We searched PubMed, Embase, Medline, Cochrane Library, and Google Scholar for studies that compared POEM and LHM for achalasia and were published between January 1, 2008 and December 31, 2014. The Methodological Index for Nonrandomized Studies (MINORS) was used to evaluate the quality of the studies. Random- and fixed-effects meta-analytical models were used, and between-study heterogeneity was assessed.Four nonrandomized comparative studies that included 317 patients (125 in the POEM group and 192 in the LHM group) met our research criteria and were assessed. There were no differences between the POEM and LHM groups in terms of sex, preoperative Eckhart score, length of myotomy, operation time, length of hospital stay, and complications. The patients in the POEM group were older than those in the LHM group (MD =2.81, 95% CI 0.27-5.35; P = 0.03) with high between-study homogeneity (χ = 1.96, df = 2, I = 0%; P = 0.38). The patients in the POEM group had a lower Eckardt score after surgery compared with those in the LHM group (MD = -0.30, 95% CI -0.42 to -0.18; P < 0.001) with high between-study homogeneity (χ = 0.00, df = 1, I = 0%; P = 1.00).The efficacy and safety of POEM appear to be comparable to those of LHM. Multicenter and randomized trials with larger sample size are needed to further compare the efficacy and safety of POEM and LHM for the treatment of achalasia.

Discovering non-random segregation of sister chromatids: The naïve treatment of a premature discovery

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Karl G. Lark

2013-02-01

Full Text Available The discovery of non-random chromosome segregation is discussed from the perspective of what was known in1965 and1966. The distinction between daughter, parent or grandparent strands of DNA was developed in a bacterial system and led to the discovery that multiple copies of DNA elements of bacteria are not distributed randomly with respect to the age of the template strand. Experiments with higher eukaryotic cells demonstrated that during mitosis Mendel’s laws were violated; and the initial serendipitous choice of eukaryotic cell system led to the striking example of non-random segregation of parent and grand-parent DNA template strands in primary cultures of cells derived from mouse embryos. Attempts to extrapolate these findings to established TC lines demonstrated that the property could be lost. Experiments using plant root tips demonstrated that the phenomenon exists in plants and that it was, at some level, under genetic control. Despite publication in major journals and symposia (Lark et al. (1966a; Lark (1967a; 1967b; 1969, 1969a; 1969b the potential implications of these findings were ignored for several decades. Here we explore possible reasons for the pre-maturity (Stent, 1972 of this discovery.

See no evil: color blindness and perceptions of subtle racial discrimination in the workplace.

Science.gov (United States)

Offermann, Lynn R; Basford, Tessa E; Graebner, Raluca; Jaffer, Salman; De Graaf, Sumona Basu; Kaminsky, Samuel E

2014-10-01

Workplace discrimination has grown more ambiguous, with interracial interactions often perceived differently by different people. The present study adds to the literature by examining a key individual difference variable in the perception of discrimination at work, namely individual color-blind attitudes. We examined relationships between 3 dimensions of color-blind attitudes (Racial Privilege, Institutional Discrimination, and Blatant Racial Issues) and perceptions of racial microaggressions in the workplace as enacted by a White supervisor toward a Black employee (i.e., discriminatory actions ranging from subtle to overt). Findings showed that observer views on institutional discrimination fully mediated, and blatant racial issues partially mediated, the relationships between racial group membership and the perception of workplace microaggressions. Non-Hispanic Whites endorsed color blindness as institutional discrimination and blatant racial issues significantly more than members of racioethnic minority groups, and higher levels of color-blind worldviews were associated with lower likelihoods of perceiving microaggressions. Views on racial privilege did not differ significantly between members of different racial groups or affect microaggression perceptions. Implications for organizations concerned about promoting more inclusive workplaces are discussed. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

Treatment of benign esophageal stricture by Eder-Puestow or balloon dilators: a comparison between randomized and prospective nonrandomized trials.

Science.gov (United States)

Yamamoto, H; Hughes, R W; Schroeder, K W; Viggiano, T R; DiMagno, E P

1992-03-01

To determine whether the natural history of strictures is affected by the type of dilator used to treat newly diagnosed peptic strictures, we designed a prospective randomized trial to compare the results after Eder-Puestow or Medi-Tech balloon dilation. We entered 31 patients into the trial. We also prospectively followed up all 92 nonrandomized patients who underwent their first dilation for a benign stricture during the same period as the prospective randomized trial. The nonrandomized patients also underwent dilation with either the Eder-Puestow or the balloon technique at the discretion of the gastroenterologist performing the endoscopy. We found no statistically significant differences in the immediate or long-term results of the two methods among the randomized, nonrandomized, and overall combined groups. All but 1 of the 123 patients had immediate relief of dysphagia. Within each group of patients, the probability of remaining free of dysphagia 1 year after the initial dilation was approximately 20%, and the probability of not requiring a second dilation was approximately 65% with either technique. Major (esophageal rupture) and minor (bleeding or chest pain) complications occurred in 1% and 5% of the patients and 0.4% and 3% of the total dilation procedures, respectively. The esophageal rupture and four of six minor complications occurred after repeated dilations. Five of the six minor complications occurred with use of the Eder-Puestow dilators. We conclude that Eder-Puestow and balloon dilations of benign esophageal strictures are associated with similar outcomes, but repeated dilations and the Eder-Puestow technique may be associated with an increased risk of complications.

Childhood blindness at a school for the blind in Riyadh, Saudi Arabia.

Science.gov (United States)

Kotb, Amgad A; Hammouda, Ehab F; Tabbara, Khalid F

2006-02-01

To determine the major causes of eye diseases leading to visual loss and blindness among children attending a school for the blind in Riyadh, Saudi Arabia. A total of 217 school children with visual disabilities attending a school for the blind in Riyadh were included. All children were brought to The Eye Center, Riyadh, and had complete ophthalmologic examinations including visual acuity testing, biomicroscopy, ophthalmoscopy, tonometry and laboratory investigations. In addition, some patients were subjected to electroretinography (ERG), electrooculography (EOG), measurement of visual evoked potentials (VEP), and laboratory work-up for congenital disorders. There were 117 male students with an age range of 6-19 years and a mean age of 16 years. In addition, there were 100 females with an age range of 6-18 years and a mean age of 12 years. Of the 217 children, 194 (89%) were blind from genetically determined diseases or congenital disorders and 23 (11%) were blind from acquired diseases. The major causes of bilateral blindness in children were retinal degeneration, congenital glaucoma, and optic atrophy. The most common acquired causes of childhood blindness were infections and trauma. The etiological pattern of childhood blindness in Saudi Arabia has changed from microbial keratitis to genetically determined diseases of the retina and optic nerve. Currently, the most common causes of childhood blindness are genetically determined causes. Consanguineous marriages may account for the autosomal recessive disorders. Public education programs should include information for the prevention of trauma and genetic counseling. Eye examinations for preschool and school children are mandatory for the prevention and cure of blinding disorders.

An Approach to Distinguish between Plasticity and Non-random Distributions of Behavioral Types Along Urban Gradients in a Wild Passerine Bird

Directory of Open Access Journals (Sweden)

Philipp Sprau

2017-08-01

Full Text Available The impact of urbanization has been widely studied in the context of species diversity and life history evolution. Behavioral adaptation, by contrast, remains poorly understood because empirical studies rarely investigate the relative importance of two key mechanisms: plastic responses vs. non-random distributions of behavioral types. We propose here an approach that enables the simultaneous estimation of the respective roles of these distinct mechanisms. We investigated why risky behaviors are often associated with urbanization, using an urban nest box population of great tits (Parus major as a study system. We simultaneously and repeatedly quantified individual behavior (aggression and flight initiation distance as well as environmental factors characterizing level of urbanization (numbers of pedestrians, cars and cyclists. This enabled us to statistically distinguish plastic responses from patterns of non-random distributions of behavioral types. Data analyses revealed that individuals did not plastically adjust their behavior to the level of urbanization. Behavioral types were instead non-randomly distributed: bold birds occurred more frequently in areas with more cars and fewer pedestrians while shy individuals were predominantly found in areas with fewer cars and more pedestrians. These novel findings imply a major role for behavioral types in the evolutionary ecology of urban environments and call for the full integration of among- and within-individual variation in urban ecological studies.

Evaluation of the Prevention and Reactivation Care Program (PReCaP) for the hospitalized elderly: A prospective nonrandomized controlled trial

NARCIS (Netherlands)

K.J.E. Asmus-Szepesi (Kirsten); L.E. Flinterman (Linda); M.A. Koopmanschap (Marc); A.P. Nieboer (Anna); T.J.E.M. Bakker (Ton); J.P. Mackenbach (Johan); E.W. Steyerberg (Ewout)

2015-01-01

textabstractBackground: The hospitalized elderly are at risk of functional decline. We evaluated the effects and care costs of a specialized geriatric rehabilitation program aimed at preventing functional decline among at-risk hospitalized elderly. Methods: The prospective nonrandomized controlled

The Nonrandom Distribution of Interior Landforms for 100-km Diameter Craters on Mercury Suggests Regional Variations in Near-Surface Mechanical Properties

Science.gov (United States)

Herrick, R. R.

2018-05-01

There is great diversity of appearance in the interiors of 100-km diameter craters. The spatial distribution of interior landforms is clustered and nonrandom, but does not clearly correlate with Mercury's surface geology patterns.

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

OpenAIRE

Mathenge, Wanjiku; Nkurikiye, John; Limburg, Hans; Kuper, Hannah

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...

Global data on blindness.

Science.gov (United States)

Thylefors, B.; Négrel, A. D.; Pararajasegaram, R.; Dadzie, K. Y.

1995-01-01

Globally, it is estimated that there are 38 million persons who are blind. Moreover, a further 110 million people have low vision and are at great risk of becoming blind. The main causes of blindness and low vision are cataract, trachoma, glaucoma, onchocerciasis, and xerophthalmia; however, insufficient data on blindness from causes such as diabetic retinopathy and age-related macular degeneration preclude specific estimations of their global prevalence. The age-specific prevalences of the major causes of blindness that are related to age indicate that the trend will be for an increase in such blindness over the decades to come, unless energetic efforts are made to tackle these problems. More data collected through standardized methodologies, using internationally accepted (ICD-10) definitions, are needed. Data on the incidence of blindness due to common causes would be useful for calculating future trends more precisely. PMID:7704921

Mindfulness-based stress reduction compared with cognitive behavioral therapy for the treatment of insomnia comorbid with cancer: a randomized, partially blinded, noninferiority trial.

Science.gov (United States)

Garland, Sheila N; Carlson, Linda E; Stephens, Alisa J; Antle, Michael C; Samuels, Charles; Campbell, Tavis S

2014-02-10

Our study examined whether mindfulness-based stress reduction (MBSR) is noninferior to cognitive behavioral therapy for insomnia (CBT-I) for the treatment of insomnia in patients with cancer. This was a randomized, partially blinded, noninferiority trial involving patients with cancer with insomnia recruited from a tertiary cancer center in Calgary, Alberta, Canada, from September 2008 to March 2011. Assessments were conducted at baseline, after the program, and after 3 months of follow-up. The noninferiority margin was 4 points measured by the Insomnia Severity Index. Sleep diaries and actigraphy measured sleep onset latency (SOL), wake after sleep onset (WASO), total sleep time (TST), and sleep efficiency. Secondary outcomes included sleep quality, sleep beliefs, mood, and stress. Of 327 patients screened, 111 were randomly assigned (CBT-I, n = 47; MBSR, n = 64). MBSR was inferior to CBT-I for improving insomnia severity immediately after the program (P = .35), but MBSR demonstrated noninferiority at follow-up (P = .02). Sleep diary-measured SOL was reduced by 22 minutes in the CBT-I group and by 14 minutes in the MBSR group at follow-up. Similar reductions in WASO were observed for both groups. TST increased by 0.60 hours for CBT-I and 0.75 hours for MBSR. CBT-I improved sleep quality (P treatment of insomnia.

Large-area imaging reveals biologically driven non-random spatial patterns of corals at a remote reef

Science.gov (United States)

Edwards, Clinton B.; Eynaud, Yoan; Williams, Gareth J.; Pedersen, Nicole E.; Zgliczynski, Brian J.; Gleason, Arthur C. R.; Smith, Jennifer E.; Sandin, Stuart A.

2017-12-01

For sessile organisms such as reef-building corals, differences in the degree of dispersion of individuals across a landscape may result from important differences in life-history strategies or may reflect patterns of habitat availability. Descriptions of spatial patterns can thus be useful not only for the identification of key biological and physical mechanisms structuring an ecosystem, but also by providing the data necessary to generate and test ecological theory. Here, we used an in situ imaging technique to create large-area photomosaics of 16 plots at Palmyra Atoll, central Pacific, each covering 100 m2 of benthic habitat. We mapped the location of 44,008 coral colonies and identified each to the lowest taxonomic level possible. Using metrics of spatial dispersion, we tested for departures from spatial randomness. We also used targeted model fitting to explore candidate processes leading to differences in spatial patterns among taxa. Most taxa were clustered and the degree of clustering varied by taxon. A small number of taxa did not significantly depart from randomness and none revealed evidence of spatial uniformity. Importantly, taxa that readily fragment or tolerate stress through partial mortality were more clustered. With little exception, clustering patterns were consistent with models of fragmentation and dispersal limitation. In some taxa, dispersion was linearly related to abundance, suggesting density dependence of spatial patterning. The spatial patterns of stony corals are non-random and reflect fundamental life-history characteristics of the taxa, suggesting that the reef landscape may, in many cases, have important elements of spatial predictability.

An Adaptive Fuzzy-Based System to Simulate, Quantify and Compensate Color Blindness

OpenAIRE

Lee, Jinmi; Santos, Wellington Pinheiro dos

2017-01-01

About 8% of the male population of the world are affected by a determined type of color vision disturbance, which varies from the partial to complete reduction of the ability to distinguish certain colors. A considerable amount of color blind people are able to live all life long without knowing they have color vision disabilities and abnormalities. Nowadays the evolution of information technology and computer science, specifically image processing techniques and computer graphics, can be fun...

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

Science.gov (United States)

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

2013-01-01

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. 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. 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. 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.

Blind Analysis in Particle Physics

International Nuclear Information System (INIS)

Roodman, A

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 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

The Sokoto blind beggars: causes of blindness and barriers to rehabilitation services.

Science.gov (United States)

Balarabe, Aliyu Hamza; Mahmoud, Abdulraheem O; Ayanniyi, Abdulkabir Ayansiji

2014-01-01

To determine the causes of blindness and the barriers to accessing rehabilitation services (RS) among blind street beggars (bsb) in Sokoto, Nigeria. A cross-sectional survey of 202 bsb (VA blindness were diagnosed by clinical ophthalmic examination. There were 107 (53%) males and 95 (47%) females with a mean age of 49 years (SD 12.2). Most bsb 191 (94.6%) had non-formal education. Of 190 (94.1%) irreversibly bsb, 180/190 (94.7%) had no light perception (NPL) bilaterally. The major causes of blindness were non-trachomatous corneal opacity (60.8%) and trachoma corneal opacity (12.8%). There were 166 (82%) blind from avoidable causes and 190 (94.1%) were irreversibly blind with 76.1% due to avoidable causes. The available sub-standard RS were educational, vocational and financial support. The barriers to RS in the past included non-availability 151 (87.8%), inability to afford 2 (1.2%), unfelt need 4 (2.3%), family refusal 1 (0.6), ignorance 6 (3.5%) and being not linked 8 (4.7%). The barriers to RS during the study period included inability of 72 subjects (35.6%) to access RS and 59 (81.9%) were due to lack of linkage to the existing services. Corneal opacification was the major cause of blindness among bsb. The main challenges to RS include the inadequate services available, societal and users factors. Renewed efforts are warranted toward the prevention of avoidable causes of blindness especially corneal opacities. The quality of life of the blind street beggar should be improved through available, accessible and affordable well-maintained and sustained rehabilitation services.

Postural control in blind subjects.

Science.gov (United States)

Soares, Antonio Vinicius; Oliveira, Cláudia Silva Remor de; Knabben, Rodrigo José; Domenech, Susana Cristina; Borges Junior, Noe Gomes

2011-12-01

To analyze postural control in acquired and congenitally blind adults. A total of 40 visually impaired adults participated in the research, divided into 2 groups, 20 with acquired blindness and 20 with congenital blindness - 21 males and 19 females, mean age 35.8 ± 10.8. The Brazilian version of Berg Balance Scale and the motor domain of functional independence measure were utilized. On Berg Balance Scale the mean for acquired blindness was 54.0 ± 2.4 and 54.4 ± 2.5 for congenitally blind subjects; on functional independence measure the mean for acquired blind group was 87.1 ± 4.8 and 87.3 ± 2.3 for congenitally blind group. Based upon the scale used the results suggest the ability to control posture can be developed by compensatory mechanisms and it is not affected by visual loss in congenitally and acquired blindness.

Optimising delineation accuracy of tumours in PET for radiotherapy planning using blind deconvolution

International Nuclear Information System (INIS)

Guvenis, A.; Koc, A.

2015-01-01

Positron emission tomography (PET) imaging has been proven to be useful in radiotherapy planning for the determination of the metabolically active regions of tumours. Delineation of tumours, however, is a difficult task in part due to high noise levels and the partial volume effects originating mainly from the low camera resolution. The goal of this work is to study the effect of blind deconvolution on tumour volume estimation accuracy for different computer-aided contouring methods. The blind deconvolution estimates the point spread function (PSF) of the imaging system in an iterative manner in a way that the likelihood of the given image being the convolution output is maximised. In this way, the PSF of the imaging system does not need to be known. Data were obtained from a NEMA NU-2 IQ-based phantom with a GE DSTE-16 PET/CT scanner. The artificial tumour diameters were 13, 17, 22, 28 and 37 mm with a target/background ratio of 4:1. The tumours were delineated before and after blind deconvolution. Student's two-tailed paired t-test showed a significant decrease in volume estimation error ( p < 0.001) when blind deconvolution was used in conjunction with computer-aided delineation methods. A manual delineation confirmation demonstrated an improvement from 26 to 16 % for the artificial tumour of size 37 mm while an improvement from 57 to 15 % was noted for the small tumour of 13 mm. Therefore, it can be concluded that blind deconvolution of reconstructed PET images may be used to increase tumour delineation accuracy. (authors)

Postural control in blind subjects

Directory of Open Access Journals (Sweden)

Antonio Vinicius Soares

2011-12-01

Full Text Available Objective: To analyze postural control in acquired and congenitally blind adults. Methods: A total of 40 visually impaired adults participated in the research, divided into 2 groups, 20 with acquired blindness and 20 with congenital blindness - 21 males and 19 females, mean age 35.8 ± 10.8. The Brazilian version of Berg Balance Scale and the motor domain of functional independence measure were utilized. Results: On Berg Balance Scale the mean for acquired blindness was 54.0 ± 2.4 and 54.4 ± 2.5 for congenitally blind subjects; on functional independence measure the mean for acquired blind group was 87.1 ± 4.8 and 87.3 ± 2.3 for congenitally blind group. Conclusion: Based upon the scale used the results suggest the ability to control posture can be developed by compensatory mechanisms and it is not affected by visual loss in congenitally and acquired blindness.

Better outcome from arthroscopic partial meniscectomy than skin incisions only?

DEFF Research Database (Denmark)

Roos, Ewa M; Hare, Kristoffer Borbjerg; Nielsen, Sabrina Mai

2018-01-01

. In total, nine participants experienced 11 adverse events; six in the surgery group and three in the skin-incisions-only group. CONCLUSION: We found greater improvement from arthroscopic partial meniscectomy compared with skin incisions only at 2 years, with the statistical uncertainty of the between......-group difference including what could be considered clinically relevant. Because of the study being underpowered, nearly half in the sham group being non-blinded and one-third crossing over to surgery, the results cannot be generalised to the greater patient population. TRIAL REGISTRATION NUMBER: NCT01264991....

Reassessing the forest impacts of protection: the challenge of nonrandom location and a corrective method.

Science.gov (United States)

Joppa, Lucas; Pfaff, Alexander

2010-01-01

Protected areas are leading tools in efforts to slow global species loss and appear also to have a role in climate change policy. Understanding their impacts on deforestation informs environmental policies. We review several approaches to evaluating protection's impact on deforestation, given three hurdles to empirical evaluation, and note that "matching" techniques from economic impact evaluation address those hurdles. The central hurdle derives from the fact that protected areas are distributed nonrandomly across landscapes. Nonrandom location can be intentional, and for good reasons, including biological and political ones. Yet even so, when protected areas are biased in their locations toward less-threatened areas, many methods for impact evaluation will overestimate protection's effect. The use of matching techniques allows one to control for known landscape biases when inferring the impact of protection. Applications of matching have revealed considerably lower impact estimates of forest protection than produced by other methods. A reduction in the estimated impact from existing parks does not suggest, however, that protection is unable to lower clearing. Rather, it indicates the importance of variation across locations in how much impact protection could possibly have on rates of deforestation. Matching, then, bundles improved estimates of the average impact of protection with guidance on where new parks' impacts will be highest. While many factors will determine where new protected areas will be sited in the future, we claim that the variation across space in protection's impact on deforestation rates should inform site choice.

Causes and emerging trends of childhood blindness: findings from schools for the blind in Southeast Nigeria.

Science.gov (United States)

Aghaji, Ada; Okoye, Obiekwe; Bowman, Richard

2015-06-01

To ascertain the causes severe visual impairment and blindness (SVI/BL) in schools for the blind in southeast Nigeria and to evaluate temporal trends. All children who developed blindness at schools for the blind in southeast Nigeria were examined. All the data were recorded on a WHO/Prevention of Blindness (WHO/PBL) form entered into a Microsoft Access database and transferred to STATA V.12.1 for analysis. To estimate temporal trends in causes of blindness, older (>15 years) children were compared with younger (≤15 years) children. 124 children were identified with SVI/BL. The most common anatomical site of blindness was the lens (33.9%). Overall, avoidable blindness accounted for 73.4% of all blindness. Exploring trends in SVI/BL between children ≤15 years of age and those >15 years old, this study shows a reduction in avoidable blindness but an increase in cortical visual impairment in the younger age group. The results from this study show a statistically significant decrease in avoidable blindness in children ≤15 years old. Corneal blindness appears to be decreasing but cortical visual impairment seems to be emerging in the younger age group. Appropriate strategies for the prevention of avoidable childhood blindness in Nigeria need to be developed and implemented. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Fair quantum blind signatures

International Nuclear Information System (INIS)

Tian-Yin, Wang; Qiao-Yan, Wen

2010-01-01

We present a new fair blind signature scheme based on the fundamental properties of quantum mechanics. In addition, we analyse the security of this scheme, and show that it is not possible to forge valid blind signatures. Moreover, comparisons between this scheme and public key blind signature schemes are also discussed. (general)

[Visual impairment and blindness in children in a Malawian school for the blind].

Science.gov (United States)

Schulze Schwering, M; Nyrenda, M; Spitzer, M S; Kalua, K

2013-08-01

The aim of this study was to determine the anatomic sites of severe visual impairment and blindness in children in an integrated school for the blind in Malawi, and to compare the results with those of previous Malawian blind school studies. Children attending an integrated school for the blind in Malawi were examined in September 2011 using the standard WHO/PBL eye examination record for children with blindness and low vision. Visual acuity [VA] of the better eye was classified using the standardised WHO reporting form. Fifty-five pupils aged 6 to 19 years were examined, 39 (71 %) males, and 16 (29 %) females. Thirty eight (69%) were blind [BL], 8 (15 %) were severely visually impaired [SVI], 8 (15 %) visually impaired [VI], and 1 (1.8 %) was not visually impaired [NVI]. The major anatomic sites of visual loss were optic nerve (16 %) and retina (16 %), followed by lens/cataract (15 %), cornea (11 %) and lesions of the whole globe (11 %), uveal pathologies (6 %) and cortical blindness (2 %). The exact aetiology of VI or BL could not be determined in most children. Albinism accounted for 13 % (7/55) of the visual impairments. 24 % of the cases were considered to be potentially avoidable: refractive amblyopia among pseudophakic patients and corneal scaring. Optic atrophy, retinal diseases (mostly albinism) and cataracts were the major causes of severe visual impairment and blindness in children in an integrated school for the blind in Malawi. Corneal scarring was now the fourth cause of visual impairment, compared to being the commonest cause 35 years ago. Congenital cataract and its postoperative outcome were the commonest remedial causes of visual impairment. Georg Thieme Verlag KG Stuttgart · New York.

No Effects of D-Cycloserine Enhancement in Exposure With Response Prevention Therapy in Panic Disorder With Agoraphobia : A Double-Blind, Randomized Controlled Trial

NARCIS (Netherlands)

Hofmeijer-Sevink, Mieke Klein; Duits, Puck; Rijkeboer, Marleen M.; Hoogendoorn, Adriaan W.; van Megen, Harold J.; Vulink, Nienke C.; Denys, Damiaan A.; van den Hout, Marcel A.; van Balkom, Anton J.; Cath, Danielle C.

2017-01-01

Purpose/Background: D-cycloserine (DCS) is a partial N-methyl-Daspartate receptor agonist that potentially augments response to exposure therapy in anxiety disorders by enhancing extinction learning. This randomized, double-blinded, placebo-controlled augmentation trial examined (1) the

No Effects of D-Cycloserine Enhancement in Exposure With Response Prevention Therapy in Panic Disorder With Agoraphobia A Double-Blind, Randomized Controlled Trial

NARCIS (Netherlands)

Hofmeijer-Sevink, Mieke Klein; Duits, Puck; Rijkeboer, Marleen M.; Hoogendoorn, Adriaan W.; van Megen, Harold J.; Vulink, Nienke C.; Denys, Damiaan A.; van den Hout, Marcel A.; van Balkom, Anton J.; Cath, Danielle C.

2017-01-01

Purpose/Background: D-cycloserine (DCS) is a partial N-methyl-Daspartate receptor agonist that potentially augments response to exposure therapy in anxiety disorders by enhancing extinction learning. This randomized, double-blinded, placebo-controlled augmentation trial examined (1) the

Homeopathy for Depression - DEP-HOM: study protocol for a randomized, partially double-blind, placebo controlled, four armed study

Science.gov (United States)

2011-01-01

Background Homeopathy is often sought by patients with depression. In classical homeopathy, the treatment consists of two main elements: the case history and the prescription of an individually selected homeopathic remedy. Previous data suggest that individualized homeopathic Q-potencies were not inferior to the antidepressant fluoxetine in a sample of patients with moderate to severe depression. However, the question remains whether individualized homeopathic Q-potencies and/or the type of the homeopathic case history have a specific therapeutical effect in acute depression as this has not yet been investigated. The study aims to assess the two components of individualized homeopathic treatment for acute depression, i.e., to investigate the specific effect of individualized Q-potencies versus placebo and to investigate the effect of different approaches to the homeopathic case history. Methods/Design A randomized, partially double-blind, placebo-controlled, four-armed trial using a 2 × 2 factorial design with a six-week study duration per patient will be performed. 228 patients diagnosed with major depression (moderate episode) by a psychiatrist will be included. The primary endpoint is the total score on the 17-item Hamilton Depression Rating Scale after six weeks. Secondary end points are: Hamilton Depression Rating Scale total score after two and four weeks; response and remission rates, Beck Depression inventory total score, quality of life and safety at two, four and six weeks. Statistical analyses will be by intention-to-treat. The main endpoint will be analysed by a two-factorial analysis of covariance. Within this model generalized estimation equations will be used to estimate differences between verum and placebo, and between both types of case history. Discussion For the first time this study evaluates both the specific effect of homeopathic medicines and of a homeopathic case taking in patients with depression. It is an attempt to deal with the

Definition of blindness under National Programme for Control of Blindness: Do we need to revise it?

Science.gov (United States)

Vashist, Praveen; Senjam, Suraj Singh; Gupta, Vivek; Gupta, Noopur; Kumar, Atul

2017-02-01

A review appropriateness of the current definition of blindness under National Programme for Control of Blindness (NPCB), Government of India. Online search of peer-reviewed scientific published literature and guidelines using PubMed, the World Health Organization (WHO) IRIS, and Google Scholar with keywords, namely blindness and visual impairment, along with offline examination of reports of national and international organizations, as well as their cross-references was done until December 2016, to identify relevant documents on the definition of blindness. The evidence for the historical and currently adopted definition of blindness under the NPCB, the WHO, and other countries was reviewed. Differences in the NPCB and WHO definitions were analyzed to assess the impact on the epidemiological status of blindness and visual impairment in India. The differences in the criteria for blindness under the NPCB and the WHO definitions cause an overestimation of the prevalence of blindness in India. These variations are also associated with an over-representation of refractive errors as a cause of blindness and an under-representation of other causes under the NPCB definition. The targets for achieving elimination of blindness also become much more difficult to achieve under the NPCB definition. Ignoring differences in definitions when comparing the global and Indian prevalence of blindness will cause erroneous interpretations. We recommend that the appropriate modifications should be made in the NPCB definition of blindness to make it consistent with the WHO definition.

Definition of blindness under National Programme for Control of Blindness: Do we need to revise it?

Directory of Open Access Journals (Sweden)

Praveen Vashist

2017-01-01

Full Text Available A review appropriateness of the current definition of blindness under National Programme for Control of Blindness (NPCB, Government of India. Online search of peer-reviewed scientific published literature and guidelines using PubMed, the World Health Organization (WHO IRIS, and Google Scholar with keywords, namely blindness and visual impairment, along with offline examination of reports of national and international organizations, as well as their cross-references was done until December 2016, to identify relevant documents on the definition of blindness. The evidence for the historical and currently adopted definition of blindness under the NPCB, the WHO, and other countries was reviewed. Differences in the NPCB and WHO definitions were analyzed to assess the impact on the epidemiological status of blindness and visual impairment in India. The differences in the criteria for blindness under the NPCB and the WHO definitions cause an overestimation of the prevalence of blindness in India. These variations are also associated with an over-representation of refractive errors as a cause of blindness and an under-representation of other causes under the NPCB definition. The targets for achieving elimination of blindness also become much more difficult to achieve under the NPCB definition. Ignoring differences in definitions when comparing the global and Indian prevalence of blindness will cause erroneous interpretations. We recommend that the appropriate modifications should be made in the NPCB definition of blindness to make it consistent with the WHO definition.

BlindSense: An Accessibility-inclusive Universal User Interface for Blind People

Directory of Open Access Journals (Sweden)

A. Khan

2018-04-01

Full Text Available A large number of blind people use smartphone-based assistive technology to perform their common activities. In order to provide a better user experience the existing user interface paradigm needs to be revisited. A new user interface model has been proposed in this paper. A simplified, semantically consistent, and blind-friendly adaptive user interface is provided. The proposed solution is evaluated through an empirical study on 63 blind people leveraging an improved user experience in performing common activities on a smartphone.

No Effects of D-Cycloserine Enhancement in Exposure with Response Prevention Therapy in Panic Disorder with Agoraphobia : A Double-Blind, Randomized Controlled Trial

NARCIS (Netherlands)

Hofmeijer-Sevink, Mieke Klein; Duits, Puck; Rijkeboer, Marleen M.; Hoogendoorn, Adriaan W; Van Megen, Harold J.; Vulink, Nienke C.; Denys, Damiaan A.; Van Den Hout, Marcel A.; van Balkom, Anton J L M; Cath, Danielle C.

2017-01-01

Purpose/Background D-cycloserine (DCS) is a partial N-methyl-D-aspartate receptor agonist that potentially augments response to exposure therapy in anxiety disorders by enhancing extinction learning. This randomized, double-blinded, placebo-controlled augmentation trial examined (1) the

No Effects of D-Cycloserine Enhancement in Exposure With Response Prevention Therapy in Panic Disorder With Agoraphobia : A Double-Blind, Randomized Controlled Trial

NARCIS (Netherlands)

Hofmeijer-Sevink, Mieke Klein; Duits, Puck; Rijkeboer, Marleen M; Hoogendoorn, Adriaan W; van Megen, Harold J; Vulink, Nienke C; Denys, D.; van den Hout, Marcel A; van Balkom, Anton J L M; Cath, Danielle C

2017-01-01

PURPOSE/BACKGROUND: D-cycloserine (DCS) is a partial N-methyl-D-aspartate receptor agonist that potentially augments response to exposure therapy in anxiety disorders by enhancing extinction learning. This randomized, double-blinded, placebo-controlled augmentation trial examined (1) the

Causes of blindness and career choice among pupils in a blind ...

African Journals Online (AJOL)

available eye care services Furthermore there is need for career talk in schools for the blind to ... career where their potential can be fully maximized. .... tropicamide 1% eye drops. .... Foster A, Gilbert C. Epidemiology of childhood blindness.

An open-label, non-randomized comparison of venlafaxine and gabapentin as monotherapy or adjuvant therapy in the management of neuropathic pain in patients with peripheral neuropathy

Directory of Open Access Journals (Sweden)

William Eardley

2010-04-01

Full Text Available William Eardley, Cory TothDepartment of Clinical Neurosciences and the University of Calgary, Calgary, AB, CanadaAbstract: Although many therapies are used in the management of neuropathic pain (NeP due to polyneuropathy (PN, few comparison studies exist. We performed a prospective, non-randomized, unblended, efficacy comparison of the serotonin-norepinephrine reuptake inhibitor venlafaxine, as either monotherapy or adjuvant therapy, with a first-line medication for NeP, gabapentin, in patients with PN-related NeP. VAS pain scores were assessed after 3 and 6 months in intervention groups and in a cohort of patients receiving no pharmacotherapy. In a total of 223 patients, we analyzed pain quantity and quality (visual analogue scale [VAS] score, Brief Pain Inventory [BPI], quality of life and health status measures [EuroQol 5 Domains, EQ-5D], Medical Outcomes Sleep Study Scale [MOSSS], Hospital Anxiety and Depression Scale [HADS] and Short Form 36 Health Survey [SF-36] after 6 months of therapy. Significant improvements in VAS pain scores occurred for all treatment groups after 6 months. Improvements in aspects of daily life and anxiety were identified in all treatment groups. Our data suggest that monotherapy or adjuvant therapy with venlafaxine is comparable to gabapentin for NeP management. We advocate for head-to-head, randomized, double-blinded studies of current NeP therapies.Keywords: peripheral neuropathy, neuropathic pain, pharmacotherapy, venlafaxine, gabapentin

Models for the blind

DEFF Research Database (Denmark)

Olsén, Jan-Eric

2014-01-01

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......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...... 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...

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

Directory of Open Access Journals (Sweden)

Stina Cornell Kärnekull

2016-09-01

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

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....

Postictal blindness in adults.

OpenAIRE

Sadeh, M; Goldhammer, Y; Kuritsky, A

1983-01-01

Cortical blindness following grand mal seizures occurred in five adult patients. The causes of seizures included idiopathic epilepsy, vascular accident, brain cyst, acute encephalitis and chronic encephalitis. Blindness was permanent in one patients, but the others recovered within several days. Since most of the patients were either unaware of or denied their blindness, it is possible that this event often goes unrecognised. Cerebral hypoxia is considered the most likely mechanism.

INTRODUCTION Childhood blindness is increasingly becoming a ...

African Journals Online (AJOL)

number of blind years resulting from blindness in children is also equal to the number of blind years due to age related cataract.10 The burden of disability in terms of blind years in these children represents a major. CAUSES OF BLINDNESS AND VISUAL IMPAIRMENT AT THE SCHOOL FOR THE. BLIND OWO, NIGERIA.

Childhood Fears among Children Who Are Blind: The Perspective of Teachers Who Are Blind

Science.gov (United States)

Al-Zboon, Eman

2017-01-01

The aim of this study was to investigate childhood fears in children who are blind from the perspective of teachers who are blind. The study was conducted in Jordan. Forty-six teachers were interviewed. Results revealed that the main fear content in children who are blind includes fear of the unknown; environment-, transportation- and…

Can a Blind Person Play Dodge Ball? Enacting Body and Cognition with a Group of Youths with Visual Disabilities

Science.gov (United States)

Moraes, Marcia

2012-01-01

This paper presents some results of research carried out with a group of blind and partially sighted youths who are enrolled in a school for people with visual disabilities in Brazil. This research aims to promote different articulations between the body and cognition. Based on actor-network theory, it considers that having a body means learning…

Blind MuseumTourer: A System for Self-Guided Tours in Museums and Blind Indoor Navigation

OpenAIRE

Apostolos Meliones; Demetrios Sampson

2018-01-01

Notably valuable efforts have focused on helping people with special needs. In this work, we build upon the experience from the BlindHelper smartphone outdoor pedestrian navigation app and present Blind MuseumTourer, a system for indoor interactive autonomous navigation for blind and visually impaired persons and groups (e.g., pupils), which has primarily addressed blind or visually impaired (BVI) accessibility and self-guided tours in museums. A pilot prototype has been developed and is curr...

Causes of blindness and career choice among pupils in a blind school; South Western Nigeria.

Science.gov (United States)

Fadamiro, Christianah Olufunmilayo

2014-01-01

The causes of Blindness vary from place to place with about 80% of it been avoidable. Furthermore Blind people face a lot of challenges in career choice thus limiting their economic potential and full integration into the society. This study aims at identifying the causes of blindness and career choice among pupils in a school for the blind in South -Western Nigeria. This is a descriptive study of causes of blindness and career choice among 38 pupils residing in a school for the blind at Ikere -Ekiti, South Western Nigeria. Thirty eight pupils comprising of 25 males (65.8%) and 13 females (34.2%) with age range from 6-39 years were seen for the study, The commonest cause of blindness was cataract with 14 cases (36.84%) while congenital glaucoma and infection had an equal proportion of 5 cases each (13.16%). Avoidable causes constituted the greatest proportion of the causes 27 (71.05%) while unavoidable causes accounted for 11 (28.9%). The law career was the most desired profession by the pupils 11 (33.3%) followed by Teaching 9 (27.3%), other desired profession includes engineering, journalism and farming. The greatest proportion of causes of blindness identified in this study is avoidable. There is the need to create public awareness on some of the notable causes particularly cataract and motivate the community to utilize available eye care services Furthermore there is need for career talk in schools for the blind to enable them choose career where their potential can be fully maximized.

A survey of visual impairment and blindness in children attending seven schools for the blind in Myanmar.

Science.gov (United States)

Muecke, James; Hammerton, Michael; Aung, Yee Yee; Warrier, Sunil; Kong, Aimee; Morse, Anna; Holmes, Martin; Yapp, Michael; Hamilton, Carolyn; Selva, Dinesh

2009-01-01

To determine the causes of visual impairment and blindness amongst children in schools for the blind in Myanmar; to identify the avoidable causes of visual impairment and blindness; and to provide spectacles, low vision aids, orientation and mobility training and ophthalmic treatment where indicated. Two hundred and eight children under 16 years of age from all 7 schools for the blind in Myanmar were examined and the data entered into the World Health Organization Prevention of Blindness Examination Record for Childhood Blindness (WHO/PBL ERCB). One hundred and ninety nine children (95.7%) were blind (BL = Visual Acuity [VA] schools for the blind in Myanmar had potentially avoidable causes of SVI/BL. With measles being both the commonest identifiable and commonest avoidable cause, the data supports the need for a measles immunization campaign. There is also a need for a dedicated pediatric eye care center with regular ophthalmology visits to the schools, and improved optometric, low vision and orientation and mobility services in Myanmar.

Influence of 3D effects on 1D aerosol retrievals in synthetic, partially clouded scenes

International Nuclear Information System (INIS)

Stap, F.A.; Hasekamp, O.P.; Emde, C.; Röckmann, T.

2016-01-01

An important challenge in aerosol remote sensing is to retrieve aerosol properties in the vicinity of clouds and in cloud contaminated scenes. Satellite based multi-wavelength, multi-angular, photo-polarimetric instruments are particularly suited for this task as they have the ability to separate scattering by aerosol and cloud particles. Simultaneous aerosol/cloud retrievals using 1D radiative transfer codes cannot account for 3D effects such as shadows, cloud induced enhancements and darkening of cloud edges. In this study we investigate what errors are introduced on the retrieved optical and micro-physical aerosol properties, when these 3D effects are neglected in retrievals where the partial cloud cover is modeled using the Independent Pixel Approximation. To this end a generic, synthetic data set of PARASOL like observations for 3D scenes with partial, liquid water cloud cover is created. It is found that in scenes with random cloud distributions (i.e. broken cloud fields) and either low cloud optical thickness or low cloud fraction, the inversion algorithm can fit the observations and retrieve optical and micro-physical aerosol properties with sufficient accuracy. In scenes with non-random cloud distributions (e.g. at the edge of a cloud field) the inversion algorithm can fit the observations, however, here the retrieved real part of the refractive indices of both modes is biased. - Highlights: • An algorithm for retrieval of both aerosol and cloud properties is presented. • Radiative transfer models of 3D, partially clouded scenes are simulated. • Errors introduced in the retrieved aerosol properties are discussed.

Blindness and visual impairment in opera.

Science.gov (United States)

Aydin, Pinar; Ritch, Robert; O'Dwyer, John

2018-01-01

The performing arts mirror the human condition. This study sought to analyze the reasons for inclusion of visually impaired characters in opera, the cause of the blindness or near blindness, and the dramatic purpose of the blindness in the storyline. We reviewed operas from the 18 th century to 2010 and included all characters with ocular problems. We classified the cause of each character's ocular problem (organic, nonorganic, and other) in relation to the thematic setting of the opera: biblical and mythical, blind beggars or blind musicians, historical (real or fictional characters), and contemporary or futuristic. Cases of blindness in 55 characters (2 as a choir) from 38 operas were detected over 3 centuries of repertoire: 11 had trauma-related visual impairment, 5 had congenital blindness, 18 had visual impairment of unknown cause, 9 had psychogenic or malingering blindness, and 12 were symbolic or miracle-related. One opera featured an ophthalmologist curing a patient. The research illustrates that visual impairment was frequently used as an artistic device to enhance the intent and situate an opera in its time.

"Color-Blind" Racism.

Science.gov (United States)

Carr, Leslie G.

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

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 (2...

Is love blind? Sexual behavior and psychological adjustment of adolescents with blindness

NARCIS (Netherlands)

Kef, S.; Bos, H.

2006-01-01

In the present study, we examined sexual knowledge, sexual behavior, and psychological adjustment of adolescents with blindness. The sample included 36 Dutch adolescents who are blind, 16 males and 20 females. Results of the interviews revealed no problems regarding sexual knowledge or psychological

Poverty and Blindness in Nigeria: Results from the National Survey of Blindness and Visual Impairment.

Science.gov (United States)

Tafida, A; Kyari, F; Abdull, M M; Sivasubramaniam, S; Murthy, G V S; Kana, I; Gilbert, Clare E

2015-01-01

Poverty can be a cause and consequence of blindness. Some causes only affect the poorest communities (e.g. trachoma), and poor individuals are less likely to access services. In low income countries, cataract blind adults have been shown to be less economically active, indicating that blindness can exacerbate poverty. This study aims to explore associations between poverty and blindness using national survey data from Nigeria. Participants ≥40 years were examined in 305 clusters (2005-2007). Sociodemographic information, including literacy and occupation, was obtained by interview. Presenting visual acuity (PVA) was assessed using a reduced tumbling E LogMAR chart. Full ocular examination was undertaken by experienced ophthalmologists on all with PVA blind (PVA blindness were 8.5% (95% CI 7.7-9.5%), 2.5% (95% CI 2.0-3.1%), and 1.5% (95% CI 1.2-2.0%) in poorest, medium and affluent households, respectively (p = 0.001). Cause-specific prevalences of blindness from cataract, glaucoma, uncorrected aphakia and corneal opacities were significantly higher in poorer households. Cataract surgical coverage was low (37.2%), being lowest in females in poor households (25.3%). Spectacle coverage was 3 times lower in poor than affluent households (2.4% vs. 7.5%). In Nigeria, blindness is associated with poverty, in part reflecting lower access to services. Reducing avoidable causes will not be achieved unless access to services improves, particularly for the poor and women.

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

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......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......, gustatory, and olfactory dream components compared to SC participants. In contrast, LB participants only reported more tactile dream impressions. Blind and SC participants did not differ with respect to emotional and thematic dream content. However, CB participants reported more aggressive interactions...

Selecting for extinction: nonrandom disease-associated extinction homogenizes amphibian biotas.

Science.gov (United States)

Smith, Kevin G; Lips, Karen R; Chase, Jonathan M

2009-10-01

Studying the patterns in which local extinctions occur is critical to understanding how extinctions affect biodiversity at local, regional and global spatial scales. To understand the importance of patterns of extinction at a regional spatial scale, we use data from extirpations associated with a widespread pathogenic agent of amphibian decline, Batrachochytrium dendrobatidis (Bd) as a model system. We apply novel null model analyses to these data to determine whether recent extirpations associated with Bd have resulted in selective extinction and homogenization of diverse tropical American amphibian biotas. We find that Bd-associated extinctions in this region were nonrandom and disproportionately, but not exclusively, affected low-occupancy and endemic species, resulting in homogenization of the remnant amphibian fauna. The pattern of extirpations also resulted in phylogenetic homogenization at the family level and ecological homogenization of reproductive mode and habitat association. Additionally, many more species were extirpated from the region than would be expected if extirpations occurred randomly. Our results indicate that amphibian declines in this region are an extinction filter, reducing regional amphibian biodiversity to highly similar relict assemblages and ultimately causing amplified biodiversity loss at regional and global scales.

Blind Cat

Directory of Open Access Journals (Sweden)

Arka Chattopadhyay

2015-08-01

There’s no way to know whether he was blind from birth or blindness was something he had picked up from his fights with other cats. He wasn’t an urban cat. He lived in a little village, soaked in the smell of fish with a river running right beside it. Cats like these have stories of a different kind. The two-storied hotel where he lived had a wooden floor. It stood right on the riverbank and had more than a tilt towards the river, as if deliberately leaning on the water.

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...

On imitation among young and blind children

Directory of Open Access Journals (Sweden)

Maria Rita Campello Rodrigues

2016-07-01

Full Text Available This article investigates the imitation among young and blind children. The survey was conducted as a mosaic in the time since the field considerations were taken from two areas: a professional experience with early stimulation of blind babies and a workshop with blind and low vision young between 13-18 years. By statingthe situated trace of knowledge, theresearch indicates that imitation among blind young people can be one of the ways of creating a common world among young blind and sighted people. Imitation among blind young is a multi-sensory process that requires a body experience, including both blind and people who see. The paper concludes with an indication of the unique character of imitation and at the same time, with the affirmation of its relevance to the development and inclusion process of both the child and the young blind.

Non-random intrachromosomal distribution of radiation-induced chromatid aberrations in Vicia faba. [Aberration clustering

Energy Technology Data Exchange (ETDEWEB)

Schubert, I; Rieger, R [Akademie der Wissenschaften der DDR, Gatersleben. Zentralinst. fuer Genetik und Kulturpflanzenforschung

1976-04-01

A reconstructed karyotype of Vicia faba, with all chromosomes individually distinguishable, was treated with X-rays, fast neutrons, (/sup 3/H) uridine (/sup 3/HU). The distribution within metaphase chromosomes of induced chromatid aberrations was non-random for all agents used. Aberration clustering, in part agent specific, occurred in chromosome segments containing heterochromatin as defined by the presence of G bands. The pattern of aberration clustering found after treatment with /sup 3/HU did not allow the recognition of chromosome regions active in transcription during treatment. Furthermore, it was impossible to obtain unambiguous indications of the presence of AT- and GC-base clusters from the patterns of /sup 3/HT- and /sup 3/HC-induced chromatid aberrations, respectively. Possible reasons underlying these observations are discussed.

Expansion of Treatment for Hepatitis C Virus Infection by Task Shifting to Community-Based Nonspecialist Providers: A Nonrandomized Clinical Trial.

Science.gov (United States)

Kattakuzhy, Sarah; Gross, Chloe; Emmanuel, Benjamin; Teferi, Gebeyehu; Jenkins, Veronica; Silk, Rachel; Akoth, Elizabeth; Thomas, Aurielle; Ahmed, Charisse; Espinosa, Michelle; Price, Angie; Rosenthal, Elana; Tang, Lydia; Wilson, Eleanor; Bentzen, Soren; Masur, Henry; Kottilil, Shyam

2017-09-05

Direct-acting antiviral (DAA) therapy for hepatitis C virus (HCV) infection has resulted in high rates of disease cure; however, not enough specialists currently are available to provide care. To determine the efficacy of HCV treatment independently provided by nurse practitioners (NPs), primary care physicians (PCPs), or specialist physicians using DAA therapy. Nonrandomized, open-label clinical trial initiated in 2015. (ClinicalTrials.gov: NCT02339038). 13 urban, federally qualified health centers (FQHCs) in the District of Columbia. A referred sample of 600 patients, of whom 96% were black, 69% were male, 82% were treatment naive, and 20% had cirrhosis. Seventy-two percent of the patients had HCV genotype 1a infection. The baseline characteristics of patients seen by each provider type were similar. Patients were assigned in a nonrandomized but specified manner to receive treatment from 1 of 5 NPs, 5 PCPs, or 6 specialists. All providers underwent an identical 3-hour training session based on guidelines. Patients received treatment with ledipasvir-sofosbuvir, which was provided on site, according to U.S. Food and Drug Administration labeling requirements. Sustained virologic response (SVR). 516 patients achieved SVR, a response rate of 86% (95% CI, 83.0% to 88.7%), with no major safety signals. Response rates were consistent across the 3 provider types: NPs, 89.3% (CI, 83.3% to 93.8%); PCPs, 86.9% (CI, 80.6% to 91.7%); and specialists, 83.8% (CI, 79.0% to 87.8%). Patient loss to follow-up was the major cause of non-SVR. Nonrandomized patient distribution; possible referral bias. In a real-world cohort of patients at urban FQHCs, HCV treatment administered by nonspecialist providers was as safe and effective as that provided by specialists. Nurse practitioners and PCPs with compact didactic training could substantially expand the availability of community-based providers to escalate HCV therapy, bridging existing gaps in the continuum of care for patients with

Blind MuseumTourer: A System for Self-Guided Tours in Museums and Blind Indoor Navigation

Directory of Open Access Journals (Sweden)

Apostolos Meliones

2018-01-01

Full Text Available Notably valuable efforts have focused on helping people with special needs. In this work, we build upon the experience from the BlindHelper smartphone outdoor pedestrian navigation app and present Blind MuseumTourer, a system for indoor interactive autonomous navigation for blind and visually impaired persons and groups (e.g., pupils, which has primarily addressed blind or visually impaired (BVI accessibility and self-guided tours in museums. A pilot prototype has been developed and is currently under evaluation at the Tactual Museum with the collaboration of the Lighthouse for the Blind of Greece. This paper describes the functionality of the application and evaluates candidate indoor location determination technologies, such as wireless local area network (WLAN and surface-mounted assistive tactile route indications combined with Bluetooth low energy (BLE beacons and inertial dead-reckoning functionality, to come up with a reliable and highly accurate indoor positioning system adopting the latter solution. The developed concepts, including map matching, a key concept for indoor navigation, apply in a similar way to other indoor guidance use cases involving complex indoor places, such as in hospitals, shopping malls, airports, train stations, public and municipality buildings, office buildings, university buildings, hotel resorts, passenger ships, etc. The presented Android application is effectively a Blind IndoorGuide system for accurate and reliable blind indoor navigation.

Offender and offense characteristics of a nonrandom sample of mass murderers.

Science.gov (United States)

Hempel, A G; Meloy, J R; Richards, T C

1999-01-01

A nonrandom sample (N = 30) of mass murderers in the United States and Canada during the past 50 years was studied. Data suggest that such individuals are single or divorced males in their fourth decade of life with various Axis I paranoid and/or depressive conditions and Axis II personality traits and disorders, usually Clusters A and B. The mass murder is precipitated by a major loss related to employment or relationship. A warrior mentality suffuses the planning and attack behavior of the subject, and greater deaths and higher casualty rates are significantly more likely if the perpetrator is psychotic at the time of the offense. Alcohol plays a very minor role. A large proportion of subjects will convey their central motivation in a psychological abstract, a phrase or sentence yelled with great emotion at the beginning of the mass murder; but in our study sample, only 20 percent directly threatened their victims before the offense. Death by suicide or at the hands of others is the usual outcome for the mass murderer.

Sound lateralization test in adolescent blind individuals.

Science.gov (United States)

Yabe, Takao; Kaga, Kimitaka

2005-06-21

Blind individuals require to compensate for the lack of visual information by other sensory inputs. In particular, auditory inputs are crucial to such individuals. To investigate whether blind individuals localize sound in space better than sighted individuals, we tested the auditory ability of adolescent blind individuals using a sound lateralization method. The interaural time difference discrimination thresholds of blind individuals were statistically significantly shorter than those of blind individuals with residual vision and controls. These findings suggest that blind individuals have better auditory spatial ability than individuals with visual cues; therefore, some perceptual compensation occurred in the former.

Non-random alkylation of DNA sequences induced in vivo by chemical mutagens

Energy Technology Data Exchange (ETDEWEB)

Durante, M.; Geri, C.; Bonatti, S.; Parenti, R. (Universita di Pisa (Italy))

1989-08-01

Previous studies of the interaction of alkylating agents on the eukaryotic genome support the idea that induction of DNA adducts is at specific genomic sites. Here we show molecular and cytological evidence that alkylation is rather specific. Mammalian cell cultures were exposed to different doses of mutagens and the DNA was analyzed by density gradient ultracentrifugation, hydroxylapatite fractionation, and by restriction enzyme analysis. Studies with the labelled mutagens N-ethyl-N-nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine show that there is a non-random distribution of the adducts. The adducts are found more frequently in A-T, G-C rich satellite DNA and highly repetitive sequences. Analysis with restriction enzymes shows that both methyl and ethyl groups influence the restriction patterns of the enzymes HpaII and MspI that recognize specific endogenous DNA methylation. These data suggest, as a subsequent mechanism, a modification in the pattern of the normal endogenous methylation of 5-methylcytosine.

Psychologica and social adjustment to blindness: Understanding ...

African Journals Online (AJOL)

Psychologica and social adjustment to blindness: Understanding from two groups of blind people in Ilorin, Nigeria. ... Background: Blindness can cause psychosocial distress leading to maladjustment if not mitigated. Maladjustment is a secondary burden that further reduces quality of life of the blind. Adjustment is often ...

Blinding for unanticipated signatures

NARCIS (Netherlands)

D. Chaum (David)

1987-01-01

textabstractPreviously known blind signature systems require an amount of computation at least proportional to the number of signature types, and also that the number of such types be fixed in advance. These requirements are not practical in some applications. Here, a new blind signature technique

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

Science.gov (United States)

Meaidi, Amani; Jennum, Poul; Ptito, Maurice; Kupers, Ron

2014-05-01

We aimed to assess dream content in groups of congenitally blind (CB), late blind (LB), and age- and sex-matched sighted control (SC) participants. 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. All blind participants had fewer visual dream impressions compared to SC participants. In LB participants, duration of blindness was negatively correlated with duration, clarity, and color content of visual dream impressions. CB participants reported more auditory, tactile, gustatory, and olfactory dream components compared to SC participants. In contrast, LB participants only reported more tactile dream impressions. Blind and SC participants did not differ with respect to emotional and thematic dream content. However, CB participants reported more aggressive interactions and more nightmares compared to the other two groups. Our data show that blindness considerably alters the sensory composition of dreams and that onset and duration of blindness plays an important role. The increased occurrence of nightmares in CB participants may be related to a higher number of threatening experiences in daily life in this group. Copyright © 2014 Elsevier B.V. All rights reserved.

Evaluation of the Prevention and Reactivation Care Program (PReCaP) for the hospitalized elderly: A prospective nonrandomized controlled trial

OpenAIRE

Asmus-Szepesi, Kirsten; Flinterman, Linda; Koopmanschap, Marc; Nieboer, Anna; Bakker, Ton; Mackenbach, Johan; Steyerberg, Ewout

2015-01-01

textabstractBackground: The hospitalized elderly are at risk of functional decline. We evaluated the effects and care costs of a specialized geriatric rehabilitation program aimed at preventing functional decline among at-risk hospitalized elderly. Methods: The prospective nonrandomized controlled trial reported here was performed in three hospitals in the Netherlands. One hospital implemented the Prevention and Reactivation Care Program (PReCaP), while two other hospitals providing usual car...

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, except...

"VisionTouch Phone" for the Blind.

Science.gov (United States)

Yong, Robest

2013-10-01

Our objective is to enable the blind to use smartphones with touchscreens to make calls and to send text messages (sms) with ease, speed, and accuracy. We believe that with our proposed platform, which enables the blind to locate the position of the keypads, new games and education, and safety applications will be increasingly developed for the blind. This innovative idea can also be implemented on tablets for the blind, allowing them to use information websites such as Wikipedia and newspaper portals.

Motor development of blind toddler

OpenAIRE

Likar, Petra

2013-01-01

For blind toddlers, development of motor skills enables possibilities for learning and exploring the environment. The purpose of this graduation thesis is to systematically mark the milestones in development of motor skills in blind toddlers, to establish different factors which affect this development, and to discover different ways for teachers for visually impaired and parents to encourage development of motor skills. It is typical of blind toddlers that they do not experience a wide varie...

Causes of Severe Visual Impairment and Blindness: Comparative Data From Bhutanese and Laotian Schools for the Blind.

Science.gov (United States)

Farmer, Lachlan David Mailey; Ng, Soo Khai; Rudkin, Adam; Craig, Jamie; Wangmo, Dechen; Tsang, Hughie; Southisombath, Khamphoua; Griffiths, Andrew; Muecke, James

2015-01-01

To determine and compare the major causes of childhood blindness and severe visual impairment in Bhutan and Laos. Independent cross-sectional surveys. This survey consists of 2 cross-sectional observational studies. The Bhutanese component was undertaken at the National Institute for Vision Impairment, the only dedicated school for the blind in Bhutan. The Laotian study was conducted at the National Ophthalmology Centre and Vientiane School for the Blind. Children younger than age 16 were invited to participate. A detailed history and examination were performed consistent with the World Health Organization Prevention of Blindness Eye Examination Record. Of the 53 children examined in both studies, 30 were from Bhutan and 23 were from Laos. Forty percent of Bhutanese and 87.1% of Laotian children assessed were blind, with 26.7% and 4.3%, respectively, being severely visually impaired. Congenital causes of blindness were the most common, representing 45% and 43.5% of the Bhutanese and Laotian children, respectively. Anatomically, the primary site of blinding pathology differed between the cohorts. In Bhutan, the lens comprised 25%, with whole globe at 20% and retina at 15%, but in Laos, whole globe and cornea equally contributed at 30.4%, followed by retina at 17.4%. There was an observable difference in the rates of blindness/severe visual impairment due to measles, with no cases observed in the Bhutanese children but 20.7% of the total pathologies in the Laotian children attributable to congenital measles infection. Consistent with other studies, there is a high rate of blinding disease, which may be prevented, treated, or ameliorated.

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 of...

Causes of severe visual impairment and blindness in students in schools for the blind in Northwest Ethiopia.

Science.gov (United States)

Asferaw, Mulusew; Woodruff, Geoffrey; Gilbert, Clare

2017-01-01

To determine the causes of severe visual impairment and blindness (SVI/BL) among students in schools for the blind in Northwest Ethiopia and to identify preventable and treatable causes. Students attending nine schools for the blind in Northwest Ethiopia were examined and causes assigned using the standard WHO record form for children with blindness and low vision in May and June 2015. 383 students were examined, 357 (93%) of whom were severely visually impaired or blind (blind and four were SVI, total 104. The major anatomical site of visual loss among those 0-15 years was cornea/phthisis (47.1%), usually due to measles and vitamin A deficiency, followed by whole globe (22.1%), lens (9.6%) and uvea (8.7%). Among students aged 16 years and above, corneal/phthisis (76.3%) was the major anatomical cause, followed by lens (6.3%), whole globe (4.7%), uvea (3.6%) and optic nerve (3.2%). The leading underlying aetiology among students aged blindness, mainly as the result of measles and vitamin A deficiency, is still a public health problem in Northwest Ethiopia, and this has not changed as observed in other low-income countries. More than three-fourth of causes of SVI/BL in students in schools for the blind are potentially avoidable, with measles/vitamin A deficiency and cataract being the leading causes.

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 as...

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.

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 plan...

Preserved sleep microstructure in blind individuals

DEFF Research Database (Denmark)

Aubin, Sébrina; Christensen, Julie A.E.; Jennum, Poul

2018-01-01

, as light is the primary zeitgeber of the master biological clock found in the suprachiasmatic nucleus of the hypothalamus. In addition, a greater number of sleep disturbances is often reported in blind individuals. Here, we examined various electroencephalographic microstructural components of sleep, both...... during rapid-eye-movement (REM) sleep and non-REM (NREM) sleep, between blind individuals, including both of early and late onset, and normal-sighted controls. During wakefulness, occipital alpha oscillations were lower, or absent in blind individuals. During sleep, differences were observed across...... electrode derivations between the early and late blind samples, which may reflect altered cortical networking in early blindness. Despite these differences in power spectra density, the electroencephalography microstructure of sleep, including sleep spindles, slow wave activity, and sawtooth waves, remained...

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.

Blinded trials taken to the test: an analysis of randomized clinical trials that report tests for the success of blinding

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....

Colonic stem cell data are consistent with the immortal model of stem cell division under non-random strand segregation.

Science.gov (United States)

Walters, K

2009-06-01

Colonic stem cells are thought to reside towards the base of crypts of the colon, but their numbers and proliferation mechanisms are not well characterized. A defining property of stem cells is that they are able to divide asymmetrically, but it is not known whether they always divide asymmetrically (immortal model) or whether there are occasional symmetrical divisions (stochastic model). By measuring diversity of methylation patterns in colon crypt samples, a recent study found evidence in favour of the stochastic model, assuming random segregation of stem cell DNA strands during cell division. Here, the effect of preferential segregation of the template strand is considered to be consistent with the 'immortal strand hypothesis', and explore the effect on conclusions of previously published results. For a sample of crypts, it is shown how, under the immortal model, to calculate mean and variance of the number of unique methylation patterns allowing for non-random strand segregation and compare them with those observed. The calculated mean and variance are consistent with an immortal model that incorporates non-random strand segregation for a range of stem cell numbers and levels of preferential strand segregation. Allowing for preferential strand segregation considerably alters previously published conclusions relating to stem cell numbers and turnover mechanisms. Evidence in favour of the stochastic model may not be as strong as previously thought.

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

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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.

A survey of severe visual impairment and blindness in children attending thirteen schools for the blind in sri lanka.

Science.gov (United States)

Gao, Zoe; Muecke, James; Edussuriya, Kapila; Dayawansa, Ranasiri; Hammerton, Michael; Kong, Aimee; Sennanayake, Saman; Senaratne, Tissa; Marasinghe, Nirosha; Selva, Dinesh

2011-02-01

To identify the causes of blindness and severe visual impairment (BL/SVI) in children attending schools for the blind in Sri Lanka, and to provide optical devices and ophthalmic treatment where indicated. Two hundred and six children under 16 years from 13 schools for the blind in Sri Lanka were examined by a team of ophthalmologists and optometrists. Data were entered in the World Health Organization Prevention of Blindness Eye Examination Record for Childhood Blindness (WHO/PBL ERCB). Of the 206 children, 83.5% were blind (BL = Visual acuity [VA] schools for the blind in Sri Lanka had potentially avoidable causes of BL/SVI. Vision could also be improved in a third of children. The data support the need to develop specialized pediatric ophthalmic services, particularly in the face of advancing neonatal life support in Sri Lanka, and the need for increased provision of optical support.

Prevalence and causes of corneal blindness.

Science.gov (United States)

Wang, Haijing; Zhang, Yaoguang; Li, Zhijian; Wang, Tiebin; Liu, Ping

2014-04-01

The study aimed to assess the prevalence and causes of corneal blindness in a rural northern Chinese population. Cross-sectional study. The cluster random sampling method was used to select the sample. This population-based study included 11 787 participants of all ages in rural Heilongjiang Province, China. These participants underwent a detailed interview and eye examination that included the measurement of visual acuity, slit-lamp biomicroscopy and direct ophthalmoscopy. An eye was considered to have corneal blindness if the visual acuity was blindness and low vision. Among the 10 384 people enrolled in the study, the prevalence of corneal blindness is 0.3% (95% confidence interval 0.2-0.4%). The leading cause was keratitis in childhood (40.0%), followed by ocular trauma (33.3%) and keratitis in adulthood (20.0%). Age and illiteracy were found to be associated with an increased prevalence of corneal blindness. Blindness because of corneal diseases in rural areas of Northern China is a significant public health problem that needs to be given more attention. © 2013 Royal Australian and New Zealand College of Ophthalmologists.

Memory for environmental sounds in sighted, congenitally blind and late blind adults: evidence for cross-modal compensation.

Science.gov (United States)

Röder, Brigitte; Rösler, Frank

2003-10-01

Several recent reports suggest compensatory performance changes in blind individuals. It has, however, been argued that the lack of visual input leads to impoverished semantic networks resulting in the use of data-driven rather than conceptual encoding strategies on memory tasks. To test this hypothesis, congenitally blind and sighted participants encoded environmental sounds either physically or semantically. In the recognition phase, both conceptually as well as physically distinct and physically distinct but conceptually highly related lures were intermixed with the environmental sounds encountered during study. Participants indicated whether or not they had heard a sound in the study phase. Congenitally blind adults showed elevated memory both after physical and semantic encoding. After physical encoding blind participants had lower false memory rates than sighted participants, whereas the false memory rates of sighted and blind participants did not differ after semantic encoding. In order to address the question if compensatory changes in memory skills are restricted to critical periods during early childhood, late blind adults were tested with the same paradigm. When matched for age, they showed similarly high memory scores as the congenitally blind. These results demonstrate compensatory performance changes in long-term memory functions due to the loss of a sensory system and provide evidence for high adaptive capabilities of the human cognitive system.

Causes of blindness in a special education school.

Science.gov (United States)

Onakpoya, O H; Adegbehingbe, B O; Omotoye, O J; Adeoye, A O

2011-01-01

Blind children and young adults have to overcome a lifetime of emotional, social and economic difficulties. They employ non-vision dependent methods for education. To assess the causes of blindness in a special school in southwestern Nigeria to aid the development of efficient blindness prevention programmes. A cross-sectional survey of the Ekiti State Special Education School, Nigeria was conducted in May-June 2008 after approval from the Ministry of Education. All students in the blind section were examined for visual acuity, pen-torch eye examination and dilated fundoscopy in addition to taking biodata and history. Thirty blind students with mean age of 18±7.3 years and male: female ratio of 1.7:1 were examined. Blindness resulted commonly from cataract eight (26.7%), glaucoma six (20%) retinitis pigmentosa four (16.7%) and posttraumatic phthysis bulbi two (6.7%). Blindness was avoidable in 18 (61%) of cases. Glaucoma blindness was associated with redness, pain, lacrimation and photophobia in 15 (50%) and hyphaema in 16.7% of students; none of these students were on any medication at the time of study. The causes of blindness in rehabilitation school for the blind are largely avoidable and glaucoma-blind pupils face additional painful eye related morbidity during rehabilitation. While preventive measures and early intervention are needful against childhood cataract and glaucoma, regular ophthalmic consultations and medications are needed especially for glaucoma blind pupils.

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…

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.

In blind pursuit of racial equality?

Science.gov (United States)

Apfelbaum, Evan P; Pauker, Kristin; Sommers, Samuel R; Ambady, Nalini

2010-11-01

Despite receiving little empirical assessment, the color-blind approach to managing diversity has become a leading institutional strategy for promoting racial equality, across domains and scales of practice. We gauged the utility of color blindness as a means to eliminating future racial inequity--its central objective--by assessing its impact on a sample of elementary-school students. Results demonstrated that students exposed to a color-blind mind-set, as opposed to a value-diversity mind-set, were actually less likely both to detect overt instances of racial discrimination and to describe such events in a manner that would prompt intervention by certified teachers. Institutional messages of color blindness may therefore artificially depress formal reporting of racial injustice. Color-blind messages may thus appear to function effectively on the surface even as they allow explicit forms of bias to persist.

Visual impairment and blindness among the students of blind schools in Allahabad and its vicinity: A causal assessment.

Science.gov (United States)

Bhalerao, Sushank Ashok; Tandon, Mahesh; Singh, Satyaprakash; Dwivedi, Shraddha; Kumar, Santosh; Rana, Jagriti

2015-03-01

Information on eye diseases in blind school children in Allahabad is rare and sketchy. A cross-sectional study was performed to identify causes of blindness (BL) in blind school children with an aim to gather information on ocular morbidity in the blind schools in Allahabad and in its vicinity. A cross-sectional study was carried out in all the four blind schools in Allahabad and its vicinity. The students in the blind schools visited were included in the study and informed consents from parents were obtained. Relevant ocular history and basic ocular examinations were carried out on the students of the blind schools. A total of 90 students were examined in four schools of the blind in Allahabad and in the vicinity. The main causes of severe visual impairment and BL in the better eye of students were microphthalmos (34.44%), corneal scar (22.23%), anophthalmos (14.45%), pseudophakia (6.67%), optic nerve atrophy (6.67%), buphthalmos/glaucoma (3.33%), cryptophthalmos (2.22%), staphyloma (2.22%), cataract (2.22%), retinal dystrophy (2.22%), aphakia (1.11%), coloboma (1.11%), retinal detachment (1.11%), etc. Of these, 22 (24.44%) students had preventable causes of BL and another 12 (13.33%) students had treatable causes of BL. It was found that hereditary diseases, corneal scar, glaucoma and cataract were the prominent causes of BL among the students of blind schools. Almost 38% of the students had preventable or treatable causes, indicating the need of genetical counseling and focused intervention.

Visual impairment and blindness among the students of blind schools in Allahabad and its vicinity: A causal assessment

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Sushank Ashok Bhalerao

2015-01-01

Full Text Available Background/Aims: Information on eye diseases in blind school children in Allahabad is rare and sketchy. A cross-sectional study was performed to identify causes of blindness (BL in blind school children with an aim to gather information on ocular morbidity in the blind schools in Allahabad and in its vicinity. Study Design and Setting: A cross-sectional study was carried out in all the four blind schools in Allahabad and its vicinity. Materials and Methods: The students in the blind schools visited were included in the study and informed consents from parents were obtained. Relevant ocular history and basic ocular examinations were carried out on the students of the blind schools. Results: A total of 90 students were examined in four schools of the blind in Allahabad and in the vicinity. The main causes of severe visual impairment and BL in the better eye of students were microphthalmos (34.44%, corneal scar (22.23%, anophthalmos (14.45%, pseudophakia (6.67%, optic nerve atrophy (6.67%, buphthalmos/glaucoma (3.33%, cryptophthalmos (2.22%, staphyloma (2.22%, cataract (2.22%, retinal dystrophy (2.22%, aphakia (1.11%, coloboma (1.11%, retinal detachment (1.11%, etc. Of these, 22 (24.44% students had preventable causes of BL and another 12 (13.33% students had treatable causes of BL. Conclusion: It was found that hereditary diseases, corneal scar, glaucoma and cataract were the prominent causes of BL among the students of blind schools. Almost 38% of the students had preventable or treatable causes, indicating the need of genetical counseling and focused intervention.

Efficacy of low-calorie, partial meal replacement diet plans on weight and abdominal fat in obese subjects with metabolic syndrome: a double-blind, randomised controlled trial of two diet plans - one high in protein and one nutritionally balanced.

Science.gov (United States)

Lee, K; Lee, J; Bae, W K; Choi, J K; Kim, H J; Cho, B

2009-02-01

Little is known about the relative efficacy of high-protein vs. conventional diet plans that include partial meal replacements on body fat loss in obese subjects with metabolic syndrome. We aimed to evaluate the efficacy of two low-calorie diets with partial meal replacement plans-a high-protein plan (HP) and a nutritionally balanced conventional (C) plan-on reducing obesity in obese subjects with metabolic syndrome. In a 12-week, double-blind study, we randomised 75 participants to either the HP- or the C-plan group. We recorded key metrics at 0 and 12 weeks. The overall mean weight loss was 5 kg in the HP-plan group and 4.9 kg in the C-plan group (p = 0.72). Truncal fat mass decreased 1.6 kg in the HP-plan group (p or = 70% dietary compliance, however, truncal and whole body fat mass decreased more in the HP-plan group (Delta 2.2 kg and Delta 3.5 kg respectively) than in the C-plan group (Delta 1.3 kg and Delta 2.3 [corrected] kg respectively) (p < 0.05). The HP- and C-plans had a similar effect on weight and abdominal fat reduction, but the HP-plan was more effective in reducing body fat among compliant subjects.

Future trends in global blindness

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Serge Resnikoff

2012-01-01

Full Text Available The objective of this review is to discuss the available data on the prevalence and causes of global blindness, and some of the associated trends and limitations seen. A literature search was conducted using the terms "global AND blindness" and "global AND vision AND impairment", resulting in seven appropriate articles for this review. Since 1990 the estimate of global prevalence of blindness has gradually decreased when considering the best corrected visual acuity definition: 0.71% in 1990, 0.59% in 2002, and 0.55% in 2010, corresponding to a 0.73% reduction per year over the 2002-2010 period. Significant limitations were found in the comparability between the global estimates in prevalence or causes of blindness or visual impairment. These limitations arise from various factors such as uncertainties about the true cause of the impairment, the use of different definitions and methods, and the absence of data from a number of geographical areas, leading to various extrapolation methods, which in turn seriously limit comparability. Seminal to this discussion on limitations in the comparability of studies and data, is that blindness has historically been defined using best corrected visual acuity.

Causes of visual impairment and blindness in children at Instituto Benjamin Constant Blind School, Rio de Janeiro

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Daniela da Silva Verzoni

Full Text Available Abstract Objective: To determine the main causes of visual impairment and blindness in children enrolled at Instituto Benjamin Constant blind school (IBC in 2013, to aid in planning for the prevention and management of avoidable causes of blindness. Methods: Study design: cross-sectional observational study. Data was collected from medical records of students attending IBC in 2013. Causes of blindness were classified according to WHO/PBL examination record. Data were analyzed for those children aged less than 16 years using Stata 9 program. Results: Among 355 students attending IBC in 2013, 253 (73% were included in this study. Of these children, 190 (75% were blind and 63 (25% visually impaired. The major anatomical site of visual loss was retina (42%, followed by lesions of the globe (22%, optic nerve lesions (13.8%, central nervous system (8.8% and cataract/pseudophakia/aphakia (8.8%. The etiology was unknown in 41.9% and neonatal factors accounted for 30,9% of cases. Forty-eight percent of cases were potentially avoidable. Retinopathy of prematurity (ROP was the main cause of blindness and with microphthalmia, optic nerve atrophy, cataract and glaucoma accounted for more than 50% of cases. Conclusion: Provision and improvement of ROP, cataract and glaucoma screening and treatment and programs could prevent avoidable visual impairment and blindness.

Translocation 1;7 in dyshematopoiesis: possibly induced with a nonrandom geographic distribution

International Nuclear Information System (INIS)

Scheres, J.M.; Hustinx, T.W.; Holdrinet, R.S.; Geraedts, J.P.; Hagemeijer, A.; van der Blij-Philipsen, M.

1984-01-01

Eight patients with various hematologic disorders had an identical chromosomal aberration in their bone marrow or unstimulated peripheral blood, a translocation t(1;7) interpreted as t(1;7)(p11;p11). The translocation chromosome replaced one normal chromosome number7; therefore, the karyotype of the abnormal cells was trisomic for 1q and monosomic for 7q. Including four cases from the literature, a total of 12 patients (4 women, 8 men) with this translocation are known at the moment. The translocation does not seem to be associated with a specific disorder, but almost all patients had a preleukemic syndrome during some stage of their disease. It is very remarkable that 11 of the 12 patients lived in the Netherlands, and 7 patients had a history of iatrogenic exposure to alkylating agents or irradiation; one patient was a radiation worker and another one had a history of toxic exposure to chloramphenicol. It is suggested, therefore, that the t(1;7) is a possibly induced chromosomal aberration with a clearly nonrandom geographic distribution

Choice blindness in financial decision making

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Owen McLaughlin

2013-09-01

Full Text Available Choice Blindness is an experimental paradigm that examines the interplay between individuals' preferences, decisions, and expectations by manipulating the relationship between intention and choice. This paper expands upon the existing Choice Blindness framework by investigating the presence of the effect in an economically significant decision context, specifically that of pension choice. In addition, it investigates a number of secondary factors hypothesized to modulate Choice Blindness, including reaction time, risk preference, and decision complexity, as well as analysing the verbal reports of non-detecting participants. The experiment was administered to 100 participants of mixed age and educational attainment. The principal finding was that no more than 37.2% of manipulated trials were detected over all conditions, a result consistent with previous Choice Blindness research. Analysis of secondary factors found that reaction time, financial sophistication and decision complexity were significant predictors of Choice Blindness detection, while content analysis of non-detecting participant responses found that 20% implied significant preference changes and 62% adhered to initial preferences. Implications of the Choice Blindness effect in the context of behavioural economics are discussed, and an agenda for further investigation of the paradigm in this context is outlined.

Sad Facial Expressions Increase Choice Blindness.

Science.gov (United States)

Wang, Yajie; Zhao, Song; Zhang, Zhijie; Feng, Wenfeng

2017-01-01

Previous studies have discovered a fascinating phenomenon known as choice blindness-individuals fail to detect mismatches between the face they choose and the face replaced by the experimenter. Although previous studies have reported a couple of factors that can modulate the magnitude of choice blindness, the potential effect of facial expression on choice blindness has not yet been explored. Using faces with sad and neutral expressions (Experiment 1) and faces with happy and neutral expressions (Experiment 2) in the classic choice blindness paradigm, the present study investigated the effects of facial expressions on choice blindness. The results showed that the detection rate was significantly lower on sad faces than neutral faces, whereas no significant difference was observed between happy faces and neutral faces. The exploratory analysis of verbal reports found that participants who reported less facial features for sad (as compared to neutral) expressions also tended to show a lower detection rate of sad (as compared to neutral) faces. These findings indicated that sad facial expressions increased choice blindness, which might have resulted from inhibition of further processing of the detailed facial features by the less attractive sad expressions (as compared to neutral expressions).

Testing Children for Color Blindness

Science.gov (United States)

... Stories Español Eye Health / News Testing Children for Color Blindness Leer en Español: Pruebas para Detectar Daltonismo en ... study shows that kids can be tested for color blindness as soon as age 4, finds Caucasian boys ...

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.

User-centered Technologies For Blind Children

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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.

Distributed capillary adiabatic tissue homogeneity model in parametric multi-channel blind AIF estimation using DCE-MRI.

Science.gov (United States)

Kratochvíla, Jiří; Jiřík, Radovan; Bartoš, Michal; Standara, Michal; Starčuk, Zenon; Taxt, Torfinn

2016-03-01

One of the main challenges in quantitative dynamic contrast-enhanced (DCE) MRI is estimation of the arterial input function (AIF). Usually, the signal from a single artery (ignoring contrast dispersion, partial volume effects and flow artifacts) or a population average of such signals (also ignoring variability between patients) is used. Multi-channel blind deconvolution is an alternative approach avoiding most of these problems. The AIF is estimated directly from the measured tracer concentration curves in several tissues. This contribution extends the published methods of multi-channel blind deconvolution by applying a more realistic model of the impulse residue function, the distributed capillary adiabatic tissue homogeneity model (DCATH). In addition, an alternative AIF model is used and several AIF-scaling methods are tested. The proposed method is evaluated on synthetic data with respect to the number of tissue regions and to the signal-to-noise ratio. Evaluation on clinical data (renal cell carcinoma patients before and after the beginning of the treatment) gave consistent results. An initial evaluation on clinical data indicates more reliable and less noise sensitive perfusion parameter estimates. Blind multi-channel deconvolution using the DCATH model might be a method of choice for AIF estimation in a clinical setup. © 2015 Wiley Periodicals, Inc.

What It's Like to Be Color Blind

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... a green leaf might look tan or gray. Color Blindness Is Passed Down Color blindness is almost always an inherited (say: in-HER- ... Eye doctors (and some school nurses) test for color blindness by showing a picture made up of different ...

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

Causes of childhood blindness in Ghana: results from a blind school survey in Upper West Region, Ghana, and review of the literature.

Science.gov (United States)

Huh, Grace J; Simon, Judith; Grace Prakalapakorn, S

2017-06-13

Data on childhood blindness in Ghana are limited. The objectives of this study were to determine the major causes of childhood blindness and severe visual impairment (SVI) at Wa Methodist School for the Blind in Northern Ghana, and to compare our results to those published from other studies conducted in Ghana. In this retrospective study, data from an eye screening at Wa Methodist School in November 2014 were coded according to the World Health Organization/Prevention of Blindness standardized reporting methodology. Causes of blindness/SVI were categorized anatomically and etiologically, and were compared to previously published studies. Of 190 students screened, the major anatomical causes of blindness/SVI were corneal scar/phthisis bulbi (CS/PB) (n = 28, 15%) and optic atrophy (n = 23, 12%). The major etiological causes of blindness/SVI were unknown (n = 114, 60%). Eighty-three (44%) students became blind before age one year. Of four published blind school surveys conducted in Ghana, CS/PB was the most common anatomical cause of childhood blindness. Over time, the prevalence of CS/PB within blind schools decreased in the north and increased in the south. Measles-associated visual loss decreased from 52% in 1987 to 10% in 2014 at Wa Methodist School. In a blind school in northern Ghana, CS/PB was the major anatomical cause of childhood blindness/SVI. While CS/PB has been the most common anatomical cause of childhood blindness reported in Ghana, there may be regional changes in its prevalence over time. Being able to identify regional differences may guide future public health strategies to target specific causes.

Blindness causes analysis of 1854 hospitalized patients in Xinjiang

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Tian-Zuo Wang

2015-01-01

Full Text Available AIM: To analyze the blindness causes of 1854 cases in our hospital hospitalized patients, and explore the strategy and direction of blindness prevention according to the different treatment efficacy.METHODS: Cluster sampling was used to select from September 2010 to August 2013 in our hospital department of ophthalmology patients 5 473 cases, in which total of 1 854 cases of blind patients, accounting for 33.88% of hospitalized patients. According to the WHO's criteria of blindness. The BCVA enacted RESULTS: In 1 854 cases of blind patients, including 728 people right-eye blinding, 767 people left-eyes blinding, 359 people total blinding, adding up to 2 213 eyes, aged from 60～80 years old were in the majority. The top three diseases resulting blindness were cataract, diabetic retinopathy and glaucoma. In 2 213 blind eyes, the eyes treated were 2 172, of which 1 762 eyes(81.12%were succeeded, 410 eyes(18.88%failed. In the failed cases, the first three diseases were diabetic retinopathy, glaucoma and retinal detachment. CONCLUSION: In recent years, disease etiology of blinding eye has changed, but cataracts, diabetic retinopathy and glaucoma are still high incidence of blindness due, so the treatment of diabetic retinopathy, glaucoma and retinal detachment should be the emphasis for blindness prevention and treatment in the future.

Tactile spatial resolution in blind braille readers.

Science.gov (United States)

Van Boven, R W; Hamilton, R H; Kauffman, T; Keenan, J P; Pascual-Leone, A

2000-06-27

To determine if blind people have heightened tactile spatial acuity. Recently, studies using magnetic source imaging and somatosensory evoked potentials have shown that the cortical representation of the reading fingers of blind Braille readers is expanded compared to that of fingers of sighted subjects. Furthermore, the visual cortex is activated during certain tactile tasks in blind subjects but not sighted subjects. The authors hypothesized that the expanded cortical representation of fingers used in Braille reading may reflect an enhanced fidelity in the neural transmission of spatial details of a stimulus. If so, the quantitative limit of spatial acuity would be superior in blind people. The authors employed a grating orientation discrimination task in which threshold performance is accounted for by the spatial resolution limits of the neural image evoked by a stimulus. The authors quantified the psychophysical limits of spatial acuity at the middle and index fingers of 15 blind Braille readers and 15 sighted control subjects. The mean grating orientation threshold was significantly (p = 0.03) lower in the blind group (1.04 mm) compared to the sighted group (1.46 mm). The self-reported dominant reading finger in blind subjects had a mean grating orientation threshold of 0.80 mm, which was significantly better than other fingers tested. Thresholds at non-Braille reading fingers in blind subjects averaged 1.12 mm, which were also superior to sighted subjects' performances. Superior tactile spatial acuity in blind Braille readers may represent an adaptive, behavioral correlate of cortical plasticity.

Epidemiology of blindness in children.

Science.gov (United States)

Solebo, Ameenat Lola; Teoh, Lucinda; Rahi, Jugnoo

2017-09-01

An estimated 14 million of the world's children are blind. A blind child is more likely to live in socioeconomic deprivation, to be more frequently hospitalised during childhood and to die in childhood than a child not living with blindness. This update of a previous review on childhood visual impairment focuses on emerging therapies for children with severe visual disability (severe visual impairment and blindness or SVI/BL).For children in higher income countries, cerebral visual impairment and optic nerve anomalies remain the most common causes of SVI/BL, while retinopathy of prematurity (ROP) and cataract are now the most common avoidable causes. The constellation of causes of childhood blindness in lower income settings is shifting from infective and nutritional corneal opacities and congenital anomalies to more resemble the patterns seen in higher income settings. Improvements in maternal and neonatal health and investment in and maintenance of national ophthalmic care infrastructure are the key to reducing the burden of avoidable blindness. New therapeutic targets are emerging for childhood visual disorders, although the safety and efficacy of novel therapies for diseases such as ROP or retinal dystrophies are not yet clear. Population-based epidemiological research, particularly on cerebral visual impairment and optic nerve hypoplasia, is needed in order to improve understanding of risk factors and to inform and support the development of novel therapies for disorders currently considered 'untreatable'. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Blind topological measurement-based quantum computation.

Science.gov (United States)

Morimae, Tomoyuki; Fujii, Keisuke

2012-01-01

Blind quantum computation is a novel secure quantum-computing protocol that enables Alice, who does not have sufficient quantum technology at her disposal, to delegate her quantum computation to Bob, who has a fully fledged quantum computer, in such a way that Bob cannot learn anything about Alice's input, output and algorithm. A recent proof-of-principle experiment demonstrating blind quantum computation in an optical system has raised new challenges regarding the scalability of blind quantum computation in realistic noisy conditions. Here we show that fault-tolerant blind quantum computation is possible in a topologically protected manner using the Raussendorf-Harrington-Goyal scheme. The error threshold of our scheme is 4.3 × 10(-3), which is comparable to that (7.5 × 10(-3)) of non-blind topological quantum computation. As the error per gate of the order 10(-3) was already achieved in some experimental systems, our result implies that secure cloud quantum computation is within reach.

[Frequency and causes of blindness and visual impairment in schools for the blind in Yaoundé (Cameroon)].

Science.gov (United States)

Noche, Christelle Domngang; Bella, Assumpta Lucienne

2010-01-01

To determine the causes of blindness and visual impairment in students attending schools for the blind in Yaounde (Cameroon) and to estimate their frequencies. This study examined all 56 students at three schools for the blind in Yaoundé from September 15 through October 15, 2006. We collected data about their age, sex, medical and surgical history. Visual acuity was measured to determine their vision status according to the World Health Organization categories for blindness and visual impairment. All subjects underwent an ocular examination. Epi Info 3.5.1. was used for the statistical analysis of age, sex, visual acuity, causes of blindness and visual impairment, and etiologies. Fifty six people were examined: 37 men (66.1%) and 19 women (33.9%). Their mean age was 21.57 ± 10.53 years (min-max: 5-49), and 48.2% were in the 10-19 years age group (n = 27). In all, 87.5% were blind, 7.14% severely visually impaired, and 1.78% moderately visually impaired. The main causes of blindness and visual impairment in our sample were corneal disease (32.14%), optic nerve lesions (26.78%), cataract and its surgical complications (19.64%), retinal disorders (10.71%), glaucoma (8.92%, and malformations of the eyeball (1.78%). Their etiologies included congenital cataracts (19.64%), meningitis/fever (8.92%), glaucoma (7.14%), measles (5.35%), ocular trauma (5.35%), albinism (3.57%), Lyell syndrome (1.8%), and alcohol ingestion (1.8%). Etiology was unknown in 46.42%. Fifty per cent of these causes of blindness and visual impairment were treatable and/or preventable. Corneal lesions were the main cause of blindness and visual impairment in our sample. Fifty per cent of the causes found were treatable and/or preventable. Thus, substantial efforts are required to ensure access to better quality specialist ocular care. Furthermore, local authorities should create more centers specialised in the rehabilitation of the visual handicapped.

p15PAF is an intrinsically disordered protein with nonrandom structural preferences at sites of interaction with other proteins.

Science.gov (United States)

De Biasio, Alfredo; Ibáñez de Opakua, Alain; Cordeiro, Tiago N; Villate, Maider; Merino, Nekane; Sibille, Nathalie; Lelli, Moreno; Diercks, Tammo; Bernadó, Pau; Blanco, Francisco J

2014-02-18

We present to our knowledge the first structural characterization of the proliferating-cell-nuclear-antigen-associated factor p15(PAF), showing that it is monomeric and intrinsically disordered in solution but has nonrandom conformational preferences at sites of protein-protein interactions. p15(PAF) is a 12 kDa nuclear protein that acts as a regulator of DNA repair during DNA replication. The p15(PAF) gene is overexpressed in several types of human cancer. The nearly complete NMR backbone assignment of p15(PAF) allowed us to measure 86 N-H(N) residual dipolar couplings. Our residual dipolar coupling analysis reveals nonrandom conformational preferences in distinct regions, including the proliferating-cell-nuclear-antigen-interacting protein motif (PIP-box) and the KEN-box (recognized by the ubiquitin ligase that targets p15(PAF) for degradation). In accordance with these findings, analysis of the (15)N R2 relaxation rates shows a relatively reduced mobility for the residues in these regions. The agreement between the experimental small angle x-ray scattering curve of p15(PAF) and that computed from a statistical coil ensemble corrected for the presence of local secondary structural elements further validates our structural model for p15(PAF). The coincidence of these transiently structured regions with protein-protein interaction and posttranslational modification sites suggests a possible role for these structures as molecular recognition elements for p15(PAF). Copyright © 2014 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Blind Signal Classification via Spare Coding

Science.gov (United States)

2016-04-10

Blind Signal Classification via Sparse Coding Youngjune Gwon MIT Lincoln Laboratory gyj@ll.mit.edu Siamak Dastangoo MIT Lincoln Laboratory sia...achieve blind signal classification with no prior knowledge about signals (e.g., MCS, pulse shaping) in an arbitrary RF channel. Since modulated RF...classification method. Our results indicate that we can separate different classes of digitally modulated signals from blind sampling with 70.3% recall and 24.6

Environment and Blindness Situation in Iran

Directory of Open Access Journals (Sweden)

Soraya Askari

2010-04-01

Full Text Available Objectives: The purpose of this study is to describe the experiences of adults with acquired blindness while performing the daily activities of normal life and to investigated the role of environmental factors in this process. Methods: A qualitative phenomenological method has been designed for this study. A sample of 22 adults with acquired blindness who were blind for more than 5 years of life were purposefully selected and semi-structured in-depth interviews were conducted with them. The interviews were transcribed verbatim, coded and analyzed using van Manen’s method. Results: The five clustered themes that emerged from the interviews included: 1 Products and technology-discusses the benefits and drawbacks of using advanced technology to promote independence, 2 Physical environment-“The streets are like an obstacle course”, 3 Support and relationships-refers to the assistance that blind people receive from family, friends, and society, 4 Attitudes-includes family and social attitudes toward blind people, 5 Services and policies-social security, supportive acts, economic factors, educational problems and providing services. Discusion: Findings identify how the daily living activities of blind people are affected by environmental factors and what those factors are. The results will enable occupational therapists and other health care professionals who are involved with blind people to become more competent during assessment, counseling, teaching, giving support, or other interventions as needed to assist blind people. Recommendations for further research include more studies of this population to identify other challenges over time. This would facilitate long-term goals in the care. Studies that include more diversity in demographic characteristics would provide greater generalization. Some characteristics such as adolescent age group, married and single, ethnicity, and socioeconomic status are particularly important to target.

A nonrandomized trial of vitamin D supplementation for Barrett's esophagus.

Directory of Open Access Journals (Sweden)

Linda C Cummings

Full Text Available Vitamin D deficiency may increase esophageal cancer risk. Vitamin D affects genes regulating proliferation, apoptosis, and differentiation and induces the tumor suppressor 15-hydroxyprostaglandin dehydrogenase (PGDH in other cancers. This nonrandomized interventional study assessed effects of vitamin D supplementation in Barrett's esophagus (BE. We hypothesized that vitamin D supplementation may have beneficial effects on gene expression including 15-PGDH in BE.BE subjects with low grade or no dysplasia received vitamin D3 (cholecalciferol 50,000 international units weekly plus a proton pump inhibitor for 12 weeks. Esophageal biopsies from normal plus metaplastic BE epithelium and blood samples were obtained before and after vitamin D supplementation. Serum 25-hydroxyvitamin D was measured to characterize vitamin D status. Esophageal gene expression was assessed using microarrays.18 study subjects were evaluated. The baseline mean serum 25-hydroxyvitamin D level was 27 ng/mL (normal ≥30 ng/mL. After vitamin D supplementation, 25-hydroxyvitamin D levels rose significantly (median increase of 31.6 ng/mL, p<0.001. There were no significant changes in gene expression from esophageal squamous or Barrett's epithelium including 15-PGDH after supplementation.BE subjects were vitamin D insufficient. Despite improved vitamin D status with supplementation, no significant alterations in gene expression profiles were noted. If vitamin D supplementation benefits BE, a longer duration or higher dose of supplementation may be needed.

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...

Unblinding the dark matter blind spots

International Nuclear Information System (INIS)

Han, Tao; Kling, Felix

2017-01-01

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

Deaf-Blind Perspectives, 2000-2001.

Science.gov (United States)

Malloy, Peggy, Ed.

2001-01-01

These three issues of "Deaf-Blind Perspectives" feature the following articles: (1) "A Group for Students with Usher Syndrome in South Louisiana" (Faye Melancon); (2) "Simply Emily," which discusses a budding friendship between a girl with deaf-blindness and a peer; (3) "Intervener Update" (Peggy Malloy and…

Finding Objects for Assisting Blind People

OpenAIRE

Yi, Chucai; Flores, Roberto W.; Chincha, Ricardo; Tian, YingLi

2013-01-01

Computer vision technology has been widely used for blind assistance, such as navigation and wayfinding. However, few camera-based systems are developed for helping blind or visually-impaired people to find daily necessities. In this paper, we propose a prototype system of blind-assistant object finding by camera-based network and matching-based recognition. We collect a dataset of daily necessities and apply Speeded-Up Robust Features (SURF) and Scale Invariant Feature Transform (SIFT) featu...

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) A...

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...

Epidemic spreading in networks with nonrandom long-range interactions.

Science.gov (United States)

Estrada, Ernesto; Kalala-Mutombo, Franck; Valverde-Colmeiro, Alba

2011-09-01

An "infection," understood here in a very broad sense, can be propagated through the network of social contacts among individuals. These social contacts include both "close" contacts and "casual" encounters among individuals in transport, leisure, shopping, etc. Knowing the first through the study of the social networks is not a difficult task, but having a clear picture of the network of casual contacts is a very hard problem in a society of increasing mobility. Here we assume, on the basis of several pieces of empirical evidence, that the casual contacts between two individuals are a function of their social distance in the network of close contacts. Then, we assume that we know the network of close contacts and infer the casual encounters by means of nonrandom long-range (LR) interactions determined by the social proximity of the two individuals. This approach is then implemented in a susceptible-infected-susceptible (SIS) model accounting for the spread of infections in complex networks. A parameter called "conductance" controls the feasibility of those casual encounters. In a zero conductance network only contagion through close contacts is allowed. As the conductance increases the probability of having casual encounters also increases. We show here that as the conductance parameter increases, the rate of propagation increases dramatically and the infection is less likely to die out. This increment is particularly marked in networks with scale-free degree distributions, where infections easily become epidemics. Our model provides a general framework for studying epidemic spreading in networks with arbitrary topology with and without casual contacts accounted for by means of LR interactions.

Glaucoma Blindness at a Tertiary Eye Care Center.

Science.gov (United States)

Stone, Jordan S; Muir, Kelly W; Stinnett, Sandra S; Rosdahl, Jullia A

2015-01-01

Glaucoma is an important cause of irreversible blindness. This study describes the characteristics of a large, diverse group of glaucoma patients and evaluates associations between demographic and clinical characteristics and blindness. Data were gathered via retrospective chart review of patients (N = 1,454) who were seen between July 2007 and July 2010 by glaucoma service providers at Duke Eye Center. Visual acuity and visual field criteria were used to determine whether patients met the criteria for legal blindness. Descriptive and comparative statistical analyses were performed on the glaucoma patients who were not blind (n = 1,258) and those who were blind (n = 196). A subgroup analysis of only those patients with primary open-angle glaucoma was also performed. In this tertiary care population, 13% (n = 196) of glaucoma patients met criteria for legal blindness, nearly one-half of whom (n = 94) were blind from glaucoma, and another one-third of whom (n = 69) had glaucoma-related blindness. The most common glaucoma diagnosis at all levels of vision was primary open-angle glaucoma. A larger proportion of black patients compared with white patients demonstrated vision loss; the odds ratio (OR) for blindness was 2.25 (95% CI, 1.6-3.2) for black patients compared with white patients. The use of systemic antihypertensive medications was higher among patients who were blind compared with patients who were not blind (OR = 2.1; 95% CI, 1.4-3.1). A subgroup analysis including only patients with primary open-angle glaucoma showed similar results for both black race and use of systemic antihypertensive medications. The relationship between use of systemic antihypertensive medications and blindness was not different between black patients and white patients (interaction P = .268). Data were based on chart review, and associations may be confounded by unmeasured factors. Treated systemic hypertension may be correlated with blindness, and the cause cannot be explained solely

45 CFR 233.70 - Blindness.

Science.gov (United States)

2010-10-01

...). Such physician is responsible for making the agency's decision that the applicant or recipient does or... XVI of the Social Security Act must: (1) Contain a definition of blindness in terms of ophthalmic measurement. The following definition is recommended: An individual is considered blind if he has central...

Congenital color blindness in young Turkish men.

Science.gov (United States)

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

2005-04-01

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

Psychological and social adjustment to blindness: understanding from two groups of blind people in Ilorin, Nigeria.

Science.gov (United States)

Tunde-Ayinmode, Mosunmola F; Akande, Tanimola M; Ademola-Popoola, Dupe S

2011-01-01

Blindness can cause psychosocial distress leading to maladjustment if not mitigated. Maladjustment is a secondary burden that further reduces quality of life of the blind. Adjustment is often personalized and depends on nature and quality of prevailing psychosocial support and rehabilitation opportunities. This study was aimed at identifying the pattern of psychosocial adjustment in a group of relatively secluded and under-reached totally blind people in Ilorin, thus sensitizing eye doctors to psychosocial morbidity and care in the blind. A cross-sectional descriptive study using 20-item Self-Reporting Questionnaire (SRQ) and a pro forma designed by the authors to assess the psychosocial problems and risk factors in some blind people in Ilorin metropolis. The study revealed that most of the blind people were reasonably adjusted in key areas of social interaction, marriage, and family. Majority were considered to be poorly adjusted in the areas of education, vocational training, employment, and mobility. Many were also considered to be psychologically maladjusted based on the high rate of probable psychological disorder of 51%, as determined by SRQ. Factors identified as risk factors of probable psychological disorder were poor educational background and the presence of another medical disorder. Most of the blind had no access to formal education or rehabilitation system, which may have contributed to their maladjustment in the domains identified. Although their prevailing psychosocial situation would have been better prevented yet, real opportunity still exists to help this group of people in the area of social and physical rehabilitation, meeting medical needs, preventive psychiatry, preventive ophthalmology, and community health. This will require the joint efforts of medical community, government and nongovernment organizations to provide the framework for delivery of these services directly to the communities.

10 CFR 26.168 - Blind performance testing.

Science.gov (United States)

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Blind performance testing. 26.168 Section 26.168 Energy... and Human Services § 26.168 Blind performance testing. (a) Each licensee and other entity shall submit blind performance test samples to the HHS-certified laboratory. (1) During the initial 90-day period of...

Causes of blindness among hospital outpatients in Ecuador.

Science.gov (United States)

Cass, Helene; Landers, John; Benitez, Paul

2006-03-01

There is a lack of published information on the causes of blindness in Ecuador and the Latin American region in general. This study is designed to enumerate the proportions of ocular conditions contributing to blindness in an outpatient population of an ophthalmology hospital in the coastal region of Ecuador. All cases presenting to an ophthalmology outpatient clinic over a 3-week period during September 2004 were reviewed (n = 802). Visual acuity was measured using a Snellen acuity chart and those who met the criteria for blindness were included in the study (n = 118). Blindness was defined under the World Health Organization protocol as visual acuity of glaucoma (15%). Among those considered to have bilateral blindness (n = 30), refraction was the most common cause (37%), followed by cataract (23%) and glaucoma (17%). The major causes of blindness found in this study reflected those in estimated data for the region. More studies are needed to improve the quality and quantity of epidemiological data on blindness in Ecuador and Latin America. Many obstacles to successful implementation of prevention of blindness programmes in South America still need to be overcome.

An Overwhelming Desire to Be Blind: Similarities and Differences between Body Integrity Identity Disorder and the Wish for Blindness.

Science.gov (United States)

Gutschke, Katja; Stirn, Aglaja; Kasten, Erich

2017-01-01

The urge to be permanently blind is an extremely rare mental health disturbance. The underlying cause of this desire has not been determined yet, and it is uncertain whether the wish for blindness is a condition that can be included in the context of body integrity identity disorder, a condition where people feel an overwhelming need to be disabled, in many cases by amputation of a limb or through paralysis. The aim of this study is to test the hypothesis that people with a desire for blindness suffer from a greater degree of visual stress in daily activities than people in a healthy visual control group. We created a Likert scale questionnaire to measure visual stress, covering a wide range of everyday situations. The wish for blindness is extremely rare and worldwide only 5 people with an urge to be blind were found to participate in the study (4 female, 1 male). In addition, a control group of 35 (28 female, 7 male) visually healthy people was investigated. Questions addressing issues that may be experienced by participants with a desire to be blind were integrated into the questionnaire. The hypothesis that people with a desire for blindness suffer from a significantly higher visual overload in activities of daily living than visually healthy subjects was confirmed; the significance of visual stress between these groups was p < 0.01. In addition, an interview with the 5 affected participants supported the causal role of visual overload. The desire for blindness seems to originate from visual overload caused by either ophthalmologic or organic brain disturbances. In addition, psychological reasons such as certain personal character traits may play an active role in developing, maintaining, and reinforcing one's desire to be blind.

An Overwhelming Desire to Be Blind: Similarities and Differences between Body Integrity Identity Disorder and the Wish for Blindness

Directory of Open Access Journals (Sweden)

Katja Gutschke

2017-03-01

Full Text Available Background: The urge to be permanently blind is an extremely rare mental health disturbance. The underlying cause of this desire has not been determined yet, and it is uncertain whether the wish for blindness is a condition that can be included in the context of body integrity identity disorder, a condition where people feel an overwhelming need to be disabled, in many cases by amputation of a limb or through paralysis. Objective: The aim of this study is to test the hypothesis that people with a desire for blindness suffer from a greater degree of visual stress in daily activities than people in a healthy visual control group. Method: We created a Likert scale questionnaire to measure visual stress, covering a wide range of everyday situations. The wish for blindness is extremely rare and worldwide only 5 people with an urge to be blind were found to participate in the study (4 female, 1 male. In addition, a control group of 35 (28 female, 7 male visually healthy people was investigated. Questions addressing issues that may be experienced by participants with a desire to be blind were integrated into the questionnaire. Results: The hypothesis that people with a desire for blindness suffer from a significantly higher visual overload in activities of daily living than visually healthy subjects was confirmed; the significance of visual stress between these groups was p < 0.01. In addition, an interview with the 5 affected participants supported the causal role of visual overload. Conclusions: The desire for blindness seems to originate from visual overload caused by either ophthalmologic or organic brain disturbances. In addition, psychological reasons such as certain personal character traits may play an active role in developing, maintaining, and reinforcing one’s desire to be blind.

Rhythmic ganglion cell activity in bleached and blind adult mouse retinas.

Science.gov (United States)

Menzler, Jacob; Channappa, Lakshmi; Zeck, Guenther

2014-01-01

In retinitis pigmentosa--a degenerative disease which often leads to incurable blindness--the loss of photoreceptors deprives the retina from a continuous excitatory input, the so-called dark current. In rodent models of this disease this deprivation leads to oscillatory electrical activity in the remaining circuitry, which is reflected in the rhythmic spiking of retinal ganglion cells (RGCs). It remained unclear, however, if the rhythmic RGC activity is attributed to circuit alterations occurring during photoreceptor degeneration or if rhythmic activity is an intrinsic property of healthy retinal circuitry which is masked by the photoreceptor's dark current. Here we tested these hypotheses by inducing and analysing oscillatory activity in adult healthy (C57/Bl6) and blind mouse retinas (rd10 and rd1). Rhythmic RGC activity in healthy retinas was detected upon partial photoreceptor bleaching using an extracellular high-density multi-transistor-array. The mean fundamental spiking frequency in bleached retinas was 4.3 Hz; close to the RGC rhythm detected in blind rd10 mouse retinas (6.5 Hz). Crosscorrelation analysis of neighbouring wild-type and rd10 RGCs (separation distance rhythmic RGC spiking in these retinas is driven by a network of presynaptic neurons. The inhibition of glutamatergic ganglion cell input or the inhibition of gap junctional coupling abolished the rhythmic pattern. In rd10 and rd1 retinas the presynaptic network leads to local field potentials, whereas in bleached retinas additional pharmacological disinhibition is required to achieve detectable field potentials. Our results demonstrate that photoreceptor bleaching unmasks oscillatory activity in healthy retinas which shares many features with the functional phenotype detected in rd10 retinas. The quantitative physiological differences advance the understanding of the degeneration process and may guide future rescue strategies.

Blind and semi-blind ML detection for space-time block-coded OFDM wireless systems

KAUST Repository

Zaib, Alam; Al-Naffouri, Tareq Y.

2014-01-01

This paper investigates the joint maximum likelihood (ML) data detection and channel estimation problem for Alamouti space-time block-coded (STBC) orthogonal frequency-division multiplexing (OFDM) wireless systems. The joint ML estimation and data detection is generally considered a hard combinatorial optimization problem. We propose an efficient low-complexity algorithm based on branch-estimate-bound strategy that renders exact joint ML solution. However, the computational complexity of blind algorithm becomes critical at low signal-to-noise ratio (SNR) as the number of OFDM carriers and constellation size are increased especially in multiple-antenna systems. To overcome this problem, a semi-blind algorithm based on a new framework for reducing the complexity is proposed by relying on subcarrier reordering and decoding the carriers with different levels of confidence using a suitable reliability criterion. In addition, it is shown that by utilizing the inherent structure of Alamouti coding, the estimation performance improvement or the complexity reduction can be achieved. The proposed algorithms can reliably track the wireless Rayleigh fading channel without requiring any channel statistics. Simulation results presented against the perfect coherent detection demonstrate the effectiveness of blind and semi-blind algorithms over frequency-selective channels with different fading characteristics.

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…

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...... thresholds of the 5 basic tastants in 13 congenitally blind and 13 sighted control subjects. Participants also answered several eating habits questionnaires, including the Food Neophobia Scale, the Food Variety Seeking Tendency Scale, the Intuitive Eating Scale, and the Body Awareness Questionnaire. Our...

Causes of blindness and visual impairment among students in integrated schools for the blind in Nepal.

Science.gov (United States)

Shrestha, Jyoti Baba; Gnyawali, Subodh; Upadhyay, Madan Prasad

2012-12-01

To identify the causes of blindness and visual impairment among students in integrated schools for the blind in Nepal. A total of 778 students from all 67 integrated schools for the blind in Nepal were examined using the World Health Organization/Prevention of Blindness Eye Examination Record for Children with Blindness and Low Vision during the study period of 3 years. Among 831 students enrolled in the schools, 778 (93.6%) participated in the study. Mean age of students examined was 13.7 years, and the male to female ratio was 1.4:1. Among the students examined, 85.9% were blind, 10% had severe visual impairment and 4.1% were visually impaired. The cornea (22.8%) was the most common anatomical site of visual impairment, its most frequent cause being vitamin A deficiency, followed by the retina (18.4%) and lens (17.6%). Hereditary and childhood factors were responsible for visual loss in 27.9% and 22.0% of students, respectively. Etiology could not be determined in 46% of cases. Overall, 40.9% of students had avoidable causes of visual loss. Vision could be improved to a level better than 6/60 in 3.6% of students refracted. More than one third of students were visually impaired for potentially avoidable reasons, indicating lack of eye health awareness and eye care services in the community. The cause of visual impairment remained unknown in a large number of students, which indicates the need for introduction of modern diagnostic tools.

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

Science.gov (United States)

Norn, M; Permin, H

1999-01-01

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

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…

Spatial navigation by congenitally blind individuals.

Science.gov (United States)

Schinazi, Victor R; Thrash, Tyler; Chebat, Daniel-Robert

2016-01-01

Spatial navigation in the absence of vision has been investigated from a variety of perspectives and disciplines. These different approaches have progressed our understanding of spatial knowledge acquisition by blind individuals, including their abilities, strategies, and corresponding mental representations. In this review, we propose a framework for investigating differences in spatial knowledge acquisition by blind and sighted people consisting of three longitudinal models (i.e., convergent, cumulative, and persistent). Recent advances in neuroscience and technological devices have provided novel insights into the different neural mechanisms underlying spatial navigation by blind and sighted people and the potential for functional reorganization. Despite these advances, there is still a lack of consensus regarding the extent to which locomotion and wayfinding depend on amodal spatial representations. This challenge largely stems from methodological limitations such as heterogeneity in the blind population and terminological ambiguity related to the concept of cognitive maps. Coupled with an over-reliance on potential technological solutions, the field has diffused into theoretical and applied branches that do not always communicate. Here, we review research on navigation by congenitally blind individuals with an emphasis on behavioral and neuroscientific evidence, as well as the potential of technological assistance. Throughout the article, we emphasize the need to disentangle strategy choice and performance when discussing the navigation abilities of the blind population. For further resources related to this article, please visit the WIREs website. © 2015 The Authors. WIREs Cognitive Science published by Wiley Periodicals, Inc.

Sad Facial Expressions Increase Choice Blindness

Directory of Open Access Journals (Sweden)

Yajie Wang

2018-01-01

Full Text Available Previous studies have discovered a fascinating phenomenon known as choice blindness—individuals fail to detect mismatches between the face they choose and the face replaced by the experimenter. Although previous studies have reported a couple of factors that can modulate the magnitude of choice blindness, the potential effect of facial expression on choice blindness has not yet been explored. Using faces with sad and neutral expressions (Experiment 1 and faces with happy and neutral expressions (Experiment 2 in the classic choice blindness paradigm, the present study investigated the effects of facial expressions on choice blindness. The results showed that the detection rate was significantly lower on sad faces than neutral faces, whereas no significant difference was observed between happy faces and neutral faces. The exploratory analysis of verbal reports found that participants who reported less facial features for sad (as compared to neutral expressions also tended to show a lower detection rate of sad (as compared to neutral faces. These findings indicated that sad facial expressions increased choice blindness, which might have resulted from inhibition of further processing of the detailed facial features by the less attractive sad expressions (as compared to neutral expressions.

Shape Perception and Navigation in Blind Adults

Science.gov (United States)

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

2017-01-01

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

Uniocular blindness in Delta State Teaching Hospital, Oghara, Nigeria

African Journals Online (AJOL)

Background: Uniocular blindness causes loss of binocular single vision. People with uniocular blindness are potentially at risk of developing binocular blindness. Aim: To determine the prevalence rate, causes and risk factors for uniocular blindness in a teaching hospital in southern Nigeria over a one-year period. Methods: ...

34 CFR 395.11 - Training program for blind individuals.

Science.gov (United States)

2010-07-01

... 34 Education 2 2010-07-01 2010-07-01 false Training program for blind individuals. 395.11 Section... BLIND ON FEDERAL AND OTHER PROPERTY The State Licensing Agency § 395.11 Training program for blind... be provided to blind individuals as vocational rehabilitation services under the Rehabilitation Act...

Considerations in the Treatment of the Adult Blind Patient.

Science.gov (United States)

Shulman, Dennis G.

1986-01-01

Contends that blindness is not a single clinical determinant, but, rather, that two groups of blind people exist. For those congenitally blind, lack of vision can cause developmental difficulties. For those who later acquire blindness, the premorbid psychodynamics and object relationships are most important in understanding the persons' reactions…

Epidemic spreading in networks with nonrandom long-range interactions

Science.gov (United States)

Estrada, Ernesto; Kalala-Mutombo, Franck; Valverde-Colmeiro, Alba

2011-09-01

An “infection,” understood here in a very broad sense, can be propagated through the network of social contacts among individuals. These social contacts include both “close” contacts and “casual” encounters among individuals in transport, leisure, shopping, etc. Knowing the first through the study of the social networks is not a difficult task, but having a clear picture of the network of casual contacts is a very hard problem in a society of increasing mobility. Here we assume, on the basis of several pieces of empirical evidence, that the casual contacts between two individuals are a function of their social distance in the network of close contacts. Then, we assume that we know the network of close contacts and infer the casual encounters by means of nonrandom long-range (LR) interactions determined by the social proximity of the two individuals. This approach is then implemented in a susceptible-infected-susceptible (SIS) model accounting for the spread of infections in complex networks. A parameter called “conductance” controls the feasibility of those casual encounters. In a zero conductance network only contagion through close contacts is allowed. As the conductance increases the probability of having casual encounters also increases. We show here that as the conductance parameter increases, the rate of propagation increases dramatically and the infection is less likely to die out. This increment is particularly marked in networks with scale-free degree distributions, where infections easily become epidemics. Our model provides a general framework for studying epidemic spreading in networks with arbitrary topology with and without casual contacts accounted for by means of LR interactions.

Finding Objects for Assisting Blind People.

Science.gov (United States)

Yi, Chucai; Flores, Roberto W; Chincha, Ricardo; Tian, Yingli

2013-07-01

Computer vision technology has been widely used for blind assistance, such as navigation and wayfinding. However, few camera-based systems are developed for helping blind or visually-impaired people to find daily necessities. In this paper, we propose a prototype system of blind-assistant object finding by camera-based network and matching-based recognition. We collect a dataset of daily necessities and apply Speeded-Up Robust Features (SURF) and Scale Invariant Feature Transform (SIFT) feature descriptors to perform object recognition. Experimental results demonstrate the effectiveness of our prototype system.

Microstructural descriptors and cellular automata simulation of the effects of non-random nuclei location on recrystallization in two dimensions

Directory of Open Access Journals (Sweden)

Paulo Rangel Rios

2006-06-01

Full Text Available The effect of non-random nuclei location and the efficiency of microstructural descriptors in assessing such a situation are studied. Cellular automata simulation of recrystallization in two dimensions is carried out to simulate microstrutural evolution for nuclei distribution ranging from a periodic arrangement to clusters of nuclei. The simulation results are compared in detail with microstrutural descriptors normally used to follow transformation evolution. It is shown that the contiguity is particularly relevant to detect microstructural deviations from randomness. This work focuses on recrystallization but its results are applicable to any nucleation and growth transformation.

Fuzzy-based simulation of real color blindness.

Science.gov (United States)

Lee, Jinmi; dos Santos, Wellington P

2010-01-01

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

Behaviors of Sighted Individuals Perceived by Blind Persons as Hindrances to Self-Reliance in Blind Persons.

Science.gov (United States)

Rickelman, Bonnie L.; Blaylock, Jerry N.

1983-01-01

Situations in which sighted people behaved inappropiately toward blind individuals were recalled by 60 blind subjects, who described their reactions and feelings and offered suggestions for sighted people. A lack of knowledge and understanding of the skills, abilities, and feelings of visually impaired individuals were revealed. (SEW)

Investigation of the blindness status in Haimen of Jiangsu province

Directory of Open Access Journals (Sweden)

Dong-Bing Yuan

2017-06-01

Full Text Available AIM:To investigate the cause of blindness, except those caused by cataract, in Haimen city. METHODS:According to the WHO's criteria of blindness, the blindness level was decided through ophthalmic tests by associate chief or chief ophthalmologists who were trained especially for disability evaluation. The analysis of the the leading cause were taken too. RESULTS:Totally 3 266 persons were blindness, in which 2 118 were first level blindness, 1 148 persons were second lever blindness, and 1 308 persons were male, 1 958 were female. The leading cause of blindness were retina and uveitis diseases(31.58%, genetic diseases(23.47%, cornea disease(14.49%. CONCLUSION:The leading cause of blindness are retina and uveitis diseases, genetic diseases, cornea diseases in Haimen city of Jiangsu province. Early prevention and treatment should be strengthened to reduce the occurrence of blindness.

Childhood blindness in India: a population based perspective

Science.gov (United States)

Dandona, R; Dandona, L

2003-01-01

Aim: To estimate the prevalence and causes of blindness in children in the southern Indian state of Andhra Pradesh. Methods: These data were obtained as part of two population based studies in which 6935 children ≤15 years of age participated. Blindness was defined as presenting distance visual acuity <6/60 in the better eye. Results: The prevalence of childhood blindness was 0.17% (95% confidence interval 0.09 to 0.30). Treatable refractive error caused 33.3% of the blindness, followed by 16.6% due to preventable causes (8.3% each due to vitamin A deficiency and amblyopia after cataract surgery). The major causes of the remaining blindness included congenital eye anomalies (16.7%) and retinal degeneration (16.7%). Conclusion: In the context of Vision 2020, the priorities for action to reduce childhood blindness in India are refractive error, cataract related amblyopia, and corneal diseases. PMID:12598433

Cast Partial Denture versus Acrylic Partial Denture for Replacement of Missing Teeth in Partially Edentulous Patients

Directory of Open Access Journals (Sweden)

Pramita Suwal

2017-03-01

Full Text Available Aim: To compare the effects of cast partial denture with conventional all acrylic denture in respect to retention, stability, masticatory efficiency, comfort and periodontal health of abutments. Methods: 50 adult partially edentulous patient seeking for replacement of missing teeth having Kennedy class I and II arches with or without modification areas were selected for the study. Group-A was treated with cast partial denture and Group-B with acrylic partial denture. Data collected during follow-up visit of 3 months, 6 months, and 1 year by evaluating retention, stability, masticatory efficiency, comfort, periodontal health of abutment. Results: Chi-square test was applied to find out differences between the groups at 95% confidence interval where p = 0.05. One year comparison shows that cast partial denture maintained retention and stability better than acrylic partial denture (p< 0.05. The masticatory efficiency was significantly compromising from 3rd month to 1 year in all acrylic partial denture groups (p< 0.05. The comfort of patient with cast partial denture was maintained better during the observation period (p< 0.05. Periodontal health of abutment was gradually deteriorated in all acrylic denture group (p

WITHDRAWN: Oxcarbazepine add-on for drug-resistant partial epilepsy.

Science.gov (United States)

Castillo, Sergio M; Schmidt, Dieter B; White, Sarah; Shukralla, Arif

2016-11-15

Most people with epilepsy have a good prognosis and their seizures can be well controlled with the use of a single antiepileptic drug, but up to 30% develop refractory epilepsy, especially those with partial seizures. In this review we summarize the current evidence regarding oxcarbazepine when used as an add-on treatment for drug-resistant partial epilepsy. To evaluate the effects of oxcarbazepine when used as an add-on treatment for drug-resistant partial epilepsy. We searched the Cochrane Epilepsy Group's Specialized Register (28 March 2006), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2006), MEDLINE (1966 to March 2006). No language restrictions were imposed. We checked the reference lists of retrieved studies for additional reports of relevant studies. We also contacted Novartis (manufacturers of oxcarbazepine) and experts in the field. Randomized, placebo-controlled, double-blinded, add-on trials of oxcarbazepine in patients with drug-resistant partial epilepsy. Two review authors independently assessed trials for inclusion and extracted the relevant data. The following outcomes were assessed : (a) 50% or greater reduction in seizure frequency; (b) treatment withdrawal (any reason); (c) side effects. Primary analyses were intention-to-treat. Summary odds ratios were estimated for each outcome. Two trials were included representing 961 randomized patients.Overall Odds Ratio (OR) (95% Confidence Interval (CIs)) for 50% or greater reduction in seizure frequency compared to placebo 2.96 (2.20, 4.00).Treatment withdrawal OR (95% CIs) compared to placebo 2.17 (1.59, 2.97).Side effects: OR (99% CIs) compared to placebo, ataxia 2.93 (1.72, 4.99); dizziness 3.05 (1.99, 4.67); fatigue 1.80 (1.02, 3.19); nausea 2.88 (1.77, 4.69); somnolence 2.55 (1.84, 3.55); diplopia 4.32 (2.65, 7.04), were significantly associated with oxcarbazepine. Oxcarbazepine has efficacy as an add-on treatment in patients with drug

Tai Chi Chih Compared With Cognitive Behavioral Therapy for the Treatment of Insomnia in Survivors of Breast Cancer: A Randomized, Partially Blinded, Noninferiority Trial.

Science.gov (United States)

Irwin, Michael R; Olmstead, Richard; Carrillo, Carmen; Sadeghi, Nina; Nicassio, Perry; Ganz, Patricia A; Bower, Julienne E

2017-08-10

Purpose Cognitive behavioral therapy for insomnia (CBT-I) and Tai Chi Chih (TCC), a movement meditation, improve insomnia symptoms. Here, we evaluated whether TCC is noninferior to CBT-I for the treatment of insomnia in survivors of breast cancer. Patients and Methods This was a randomized, partially blinded, noninferiority trial that involved survivors of breast cancer with insomnia who were recruited from the Los Angeles community from April 2008 to July 2012. After a 2-month phase-in period with repeated baseline assessment, participants were randomly assigned to 3 months of CBT-I or TCC and evaluated at months 2, 3 (post-treatment), 6, and 15 (follow-up). Primary outcome was insomnia treatment response-that is, marked clinical improvement of symptoms by the Pittsburgh Sleep Quality Index-at 15 months. Secondary outcomes were clinician-assessed remission of insomnia; sleep quality; total sleep time, sleep onset latency, sleep efficiency, and awake after sleep onset, derived from sleep diaries; polysomnography; and symptoms of fatigue, sleepiness, and depression. Results Of 145 participants who were screened, 90 were randomly assigned (CBT-I: n = 45; TCC: n = 45). The proportion of participants who showed insomnia treatment response at 15 months was 43.7% and 46.7% in CBT-I and TCC, respectively. Tests of noninferiority showed that TCC was noninferior to CBT-I at 15 months ( P = .02) and at months 3 ( P = .02) and 6 ( P insomnia remission was 46.2% and 37.9% in CBT-I and TCC, respectively. CBT-I and TCC groups showed robust improvements in sleep quality, sleep diary measures, and related symptoms (all P insomnia. TCC, a mindful movement meditation, was found to be statistically noninferior to CBT-I, the gold standard for behavioral treatment of insomnia.

Haptic orientation perception benefits from visual experience : Evidence from early-blind, late-blind, and sighted people

NARCIS (Netherlands)

Postma, Albert; Zuidhoek, Sander; Noordzij, Matthijs L.; Kappers, A. M L

2008-01-01

Early-blind, late-blind, and blindfolded sighted participants were presented with two haptic allocentric spatial tasks: a parallel-setting task, in an immediate and a 10-sec delay condition, and a task in which the orientation of a single bar was judged verbally. With respect to deviation size, the

34 CFR 395.14 - The State Committee of Blind Vendors.

Science.gov (United States)

2010-07-01

... 34 Education 2 2010-07-01 2010-07-01 false The State Committee of Blind Vendors. 395.14 Section... BLIND ON FEDERAL AND OTHER PROPERTY The State Licensing Agency § 395.14 The State Committee of Blind... Blind Vendors which, to the extent possible, shall be fully representative of all blind vendors in the...

Actual Performance aNalysis of Innovative Blinds

Directory of Open Access Journals (Sweden)

Giedrius Šiupšinskas

2016-10-01

Full Text Available The paper analyses the innovative internal blinds, which allow to use the solar energy, received through a window for a heating, more efficiently and to ensure a greater air velocity due to the convection. Blinds are constructed that one side is covered with material, which absorbs the solar energy and the other side is reflective. Thus, there is an ability to control an amount of absorbed solar radiation and air supply temperature between the window and the blinds. In addition, the construction of the air to provide locating elements. The elements for air deflection are additionally foreseen in the construction. Due to the natural circulation cold air falls between the blinds and the window, then warms up and rises to the top. The paper presents an empirical and theoretical assessment of an operation of the blinds. In addition, the analysis of the experimental researches of an air flow intensity and a dependency of temperature increase from external (climatic conditions is performed.

Subcortical functional reorganization due to early blindness.

Science.gov (United States)

Coullon, Gaelle S L; Jiang, Fang; Fine, Ione; Watkins, Kate E; Bridge, Holly

2015-04-01

Lack of visual input early in life results in occipital cortical responses to auditory and tactile stimuli. However, it remains unclear whether cross-modal plasticity also occurs in subcortical pathways. With the use of functional magnetic resonance imaging, auditory responses were compared across individuals with congenital anophthalmia (absence of eyes), those with early onset (in the first few years of life) blindness, and normally sighted individuals. We find that the superior colliculus, a "visual" subcortical structure, is recruited by the auditory system in congenital and early onset blindness. Additionally, auditory subcortical responses to monaural stimuli were altered as a result of blindness. Specifically, responses in the auditory thalamus were equally strong to contralateral and ipsilateral stimulation in both groups of blind subjects, whereas sighted controls showed stronger responses to contralateral stimulation. These findings suggest that early blindness results in substantial reorganization of subcortical auditory responses. Copyright © 2015 the American Physiological Society.

Application of a nonrandomized stepped wedge design to evaluate an evidence-based quality improvement intervention: a proof of concept using simulated data on patient-centered medical homes.

Science.gov (United States)

Huynh, Alexis K; Lee, Martin L; Farmer, Melissa M; Rubenstein, Lisa V

2016-10-21

Stepped wedge designs have gained recognition as a method for rigorously assessing implementation of evidence-based quality improvement interventions (QIIs) across multiple healthcare sites. In theory, this design uses random assignment of sites to successive QII implementation start dates based on a timeline determined by evaluators. However, in practice, QII timing is often controlled more by site readiness. We propose an alternate version of the stepped wedge design that does not assume the randomized timing of implementation while retaining the method's analytic advantages and applying to a broader set of evaluations. To test the feasibility of a nonrandomized stepped wedge design, we developed simulated data on patient care experiences and on QII implementation that had the structures and features of the expected data from a planned QII. We then applied the design in anticipation of performing an actual QII evaluation. We used simulated data on 108,000 patients to model nonrandomized stepped wedge results from QII implementation across nine primary care sites over 12 quarters. The outcome we simulated was change in a single self-administered question on access to care used by Veterans Health Administration (VA), based in the United States, as part of its quarterly patient ratings of quality of care. Our main predictors were QII exposure and time. Based on study hypotheses, we assigned values of 4 to 11 % for improvement in access when sites were first exposed to implementation and 1 to 3 % improvement in each ensuing time period thereafter when sites continued with implementation. We included site-level (practice size) and respondent-level (gender, race/ethnicity) characteristics that might account for nonrandomized timing in site implementation of the QII. We analyzed the resulting data as a repeated cross-sectional model using HLM 7 with a three-level hierarchical data structure and an ordinal outcome. Levels in the data structure included patient ratings

Enhanced tactile encoding and memory recognition in congenital blindness.

Science.gov (United States)

D'Angiulli, Amedeo; Waraich, Paul

2002-06-01

Several behavioural studies have shown that early-blind persons possess superior tactile skills. Since neurophysiological data show that early-blind persons recruit visual as well as somatosensory cortex to carry out tactile processing (cross-modal plasticity), blind persons' sharper tactile skills may be related to cortical re-organisation resulting from loss of vision early in their life. To examine the nature of blind individuals' tactile superiority and its implications for cross-modal plasticity, we compared the tactile performance of congenitally totally blind, low-vision and sighted children on raised-line picture identification test and re-test, assessing effects of task familiarity, exploratory strategy and memory recognition. What distinguished the blind from the other children was higher memory recognition and higher tactile encoding associated with efficient exploration. These results suggest that enhanced perceptual encoding and recognition memory may be two cognitive correlates of cross-modal plasticity in congenital blindness.

Tackling the high burden of blindness

African Journals Online (AJOL)

... care delivery, and tackling the five major eye conditions that contribute to most blindness could reduce the current burden of blindness. This would open the window for addressing glaucoma, diabetic retinopathy, and macula degeneration which are the new emerging global consequences of non-communicable diseases.

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

Differences between early-blind, late-blind, and blindfolded-sighted people in haptic spatial-configuration learning and resulting memory traces.

Science.gov (United States)

Postma, Albert; Zuidhoek, Sander; Noordzij, Matthijs L; Kappers, Astrid M L

2007-01-01

The roles of visual and haptic experience in different aspects of haptic processing of objects in peripersonal space are examined. In three trials, early-blind, late-blind, and blindfolded-sighted individuals had to match ten shapes haptically to the cut-outs in a board as fast as possible. Both blind groups were much faster than the sighted in all three trials. All three groups improved considerably from trial to trial. In particular, the sighted group showed a strong improvement from the first to the second trial. While superiority of the blind remained for speeded matching after rotation of the stimulus frame, coordinate positional-memory scores in a non-speeded free-recall trial showed no significant differences between the groups. Moreover, when assessed with a verbal response, categorical spatial-memory appeared strongest in the late-blind group. The role of haptic and visual experience thus appears to depend on the task aspect tested.

Random and non-random mating populations: Evolutionary dynamics in meiotic drive.

Science.gov (United States)

Sarkar, Bijan

2016-01-01

Game theoretic tools are utilized to analyze a one-locus continuous selection model of sex-specific meiotic drive by considering nonequivalence of the viabilities of reciprocal heterozygotes that might be noticed at an imprinted locus. The model draws attention to the role of viability selections of different types to examine the stable nature of polymorphic equilibrium. A bridge between population genetics and evolutionary game theory has been built up by applying the concept of the Fundamental Theorem of Natural Selection. In addition to pointing out the influences of male and female segregation ratios on selection, configuration structure reveals some noted results, e.g., Hardy-Weinberg frequencies hold in replicator dynamics, occurrence of faster evolution at the maximized variance fitness, existence of mixed Evolutionarily Stable Strategy (ESS) in asymmetric games, the tending evolution to follow not only a 1:1 sex ratio but also a 1:1 different alleles ratio at particular gene locus. Through construction of replicator dynamics in the group selection framework, our selection model introduces a redefining bases of game theory to incorporate non-random mating where a mating parameter associated with population structure is dependent on the social structure. Also, the model exposes the fact that the number of polymorphic equilibria will depend on the algebraic expression of population structure. Copyright © 2015 Elsevier Inc. All rights reserved.

Blinde børn - integration eller isolation?

DEFF Research Database (Denmark)

Bengtsson, Steen; Cayuelas Mateu, Nuria; Høst, Anders

Blinde børn har i de senere årtier været integreret i den almindelige skole. Men betyder det, at de bliver bedre forberedt til et integreret liv som voksne? Det er langt fra sikkert, viser denne undersøgelse af blinde børn. Skolen sørger for, at de blinde børn har en støttelærer, så de får det he...

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....

Retrieval and phenomenology of autobiographical memories in blind individuals.

Science.gov (United States)

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

2015-01-01

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

Calendar systems and communication of deaf-blind children

Directory of Open Access Journals (Sweden)

Jablan Branka

2012-01-01

Full Text Available The aim of this paper is to explain the calendar systems and their role in teaching deaf-blind children. Deaf-blind persons belong to a group of multiple disabled persons. This disability should not be observed as a simple composite of visual and hearing impairments, but as a combination of sensory impairments that require special assistance in the development, communication and training for independent living. In our environment, deaf-blind children are being educated in schools for children with visual impairments or in schools for children with hearing impairments (in accordance with the primary impairment. However, deaf-blind children cannot be trained by means of special programs for children with hearing impairment, visual impairment or other programs for students with developmental disabilities without specific attention required by such a combination of sensory impairments. Deaf-blindness must be observed as a multiple impairment that requires special work methods, especially in the field of communication, whose development is severely compromised. Communication skills in deaf-blind people can be developed by using the calendar systems. They are designed in such a manner that they can be easily attainable to children with various sensory impairments. Calendars can be used to encourage and develop communication between adult persons and a deaf-blind child.

76 FR 65099 - Blind Americans Equality Day, 2011

Science.gov (United States)

2011-10-20

... Americans Equality Day, 2011 By the President of the United States of America A Proclamation Generations of... inspiring as champions of sport. On Blind Americans Equality Day, we celebrate the achievements of blind and... interacted with the program's vendors. Though we have made progress in the march to equality for the blind...

Iterated Gate Teleportation and Blind Quantum Computation.

Science.gov (United States)

Pérez-Delgado, Carlos A; Fitzsimons, Joseph F

2015-06-05

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.

Congenital blindness improves semantic and episodic memory.

Science.gov (United States)

Pasqualotto, Achille; Lam, Jade S Y; Proulx, Michael J

2013-05-01

Previous studies reported that congenitally blind people possess superior verb-generation skills. Here we tested the impact of blindness on capacity and the fidelity of semantic memory by using a false memory paradigm. In the Deese-Roediger-McDermott paradigm, participants study lists of words that are all semantically related to a lure that is not presented. Subsequently, participants frequently recall the missing lure. We found that congenitally blind participants have enhanced memory performance for recalling the presented words and reduced false memories for the lure. The dissociation of memory capacity and fidelity provides further evidence for enhanced verbal ability in the blind, supported by their broader structural and functional brain reorganisation. Copyright © 2013 Elsevier B.V. All rights reserved.

Decentralized modal identification using sparse blind source separation

International Nuclear Information System (INIS)

Sadhu, A; Hazra, B; Narasimhan, S; Pandey, M D

2011-01-01

Popular ambient vibration-based system identification methods process information collected from a dense array of sensors centrally to yield the modal properties. In such methods, the need for a centralized processing unit capable of satisfying large memory and processing demands is unavoidable. With the advent of wireless smart sensor networks, it is now possible to process information locally at the sensor level, instead. The information at the individual sensor level can then be concatenated to obtain the global structure characteristics. A novel decentralized algorithm based on wavelet transforms to infer global structure mode information using measurements obtained using a small group of sensors at a time is proposed in this paper. The focus of the paper is on algorithmic development, while the actual hardware and software implementation is not pursued here. The problem of identification is cast within the framework of under-determined blind source separation invoking transformations of measurements to the time–frequency domain resulting in a sparse representation. The partial mode shape coefficients so identified are then combined to yield complete modal information. The transformations are undertaken using stationary wavelet packet transform (SWPT), yielding a sparse representation in the wavelet domain. Principal component analysis (PCA) is then performed on the resulting wavelet coefficients, yielding the partial mixing matrix coefficients from a few measurement channels at a time. This process is repeated using measurements obtained from multiple sensor groups, and the results so obtained from each group are concatenated to obtain the global modal characteristics of the structure

Decentralized modal identification using sparse blind source separation

Science.gov (United States)

Sadhu, A.; Hazra, B.; Narasimhan, S.; Pandey, M. D.

2011-12-01

Popular ambient vibration-based system identification methods process information collected from a dense array of sensors centrally to yield the modal properties. In such methods, the need for a centralized processing unit capable of satisfying large memory and processing demands is unavoidable. With the advent of wireless smart sensor networks, it is now possible to process information locally at the sensor level, instead. The information at the individual sensor level can then be concatenated to obtain the global structure characteristics. A novel decentralized algorithm based on wavelet transforms to infer global structure mode information using measurements obtained using a small group of sensors at a time is proposed in this paper. The focus of the paper is on algorithmic development, while the actual hardware and software implementation is not pursued here. The problem of identification is cast within the framework of under-determined blind source separation invoking transformations of measurements to the time-frequency domain resulting in a sparse representation. The partial mode shape coefficients so identified are then combined to yield complete modal information. The transformations are undertaken using stationary wavelet packet transform (SWPT), yielding a sparse representation in the wavelet domain. Principal component analysis (PCA) is then performed on the resulting wavelet coefficients, yielding the partial mixing matrix coefficients from a few measurement channels at a time. This process is repeated using measurements obtained from multiple sensor groups, and the results so obtained from each group are concatenated to obtain the global modal characteristics of the structure.

33 CFR 117.861 - Blind Slough.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Blind Slough. 117.861 Section 117.861 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Oregon § 117.861 Blind Slough. The draws of the Portland and...

Tactile maze solving in congenitally blind individuals

DEFF Research Database (Denmark)

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

2010-01-01

and environmental cues such as temperature and echolocation. We hypothesize that by limiting these cues, blind individuals will lose their advantage compared with controls in spatial navigation tasks. We therefore evaluated the performance of blind and sighted individuals in small-scale, tactile multiple T mazes....... Our results show that blindfolded sighted controls outperformed blind participants in the route-learning tasks. This suggests that, contrary to indoor large-scale spaces, navigational skills inside small-scale spaces benefit from visual experience....

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.

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...... of the posterior hippocampus in early blind individuals suggests the implication of this region in visual spatial memory. Udgivelsesdato: 2007-Mar-5......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 found...

Blinding in randomized control trials: the enigma unraveled.

Directory of Open Access Journals (Sweden)

Vartika Saxena

2016-03-01

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

Perceptual, not memorial, disruption underlies emotion-induced blindness.

Science.gov (United States)

Kennedy, Briana L; Most, Steven B

2012-04-01

Emotion-induced blindness refers to impaired awareness of stimuli appearing in the temporal wake of an emotionally arousing stimulus (S. B. Most, Chun, Widders, & Zald, 2005). In previous emotion-induced blindness experiments, participants withheld target responses until the end of a rapid stream of stimuli, even though each target appeared in the middle of the stream. The resulting interval between the targets' offset and participants' initiation of a response leaves open the possibility that emotion-induced blindness reflects a failure to encode or maintain target information in memory rather than a failure of perception. In the present study, participants engaged in a typical emotion-induced blindness task but initiated a response immediately upon seeing each target. Emotion-induced blindness was nevertheless robust. This suggests that emotion-induced blindness is not attributable to the delay between awareness of a target and the initiation of a response, but rather reflects the disruptive impact of emotional distractors on mechanisms driving conscious perception. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

Ask a Scientist: What is Color Blindness?

Medline Plus

Full Text Available ... to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health problems and requirements of the blind.” ... Clinical Studies Publications Catalog Photos ...

Lentiviral expression of retinal guanylate cyclase-1 (RetGC1 restores vision in an avian model of childhood blindness.

Directory of Open Access Journals (Sweden)

Melissa L Williams

2006-06-01

Full Text Available Leber congenital amaurosis (LCA is a genetically heterogeneous group of retinal diseases that cause congenital blindness in infants and children. Mutations in the GUCY2D gene that encodes retinal guanylate cyclase-1 (retGC1 were the first to be linked to this disease group (LCA type 1 [LCA1] and account for 10%-20% of LCA cases. These mutations disrupt synthesis of cGMP in photoreceptor cells, a key second messenger required for function of these cells. The GUCY1*B chicken, which carries a null mutation in the retGC1 gene, is blind at hatching and serves as an animal model for the study of LCA1 pathology and potential treatments in humans.A lentivirus-based gene transfer vector carrying the GUCY2D gene was developed and injected into early-stage GUCY1*B embryos to determine if photoreceptor function and sight could be restored to these animals. Like human LCA1, the avian disease shows early-onset blindness, but there is a window of opportunity for intervention. In both diseases there is a period of photoreceptor cell dysfunction that precedes retinal degeneration. Of seven treated animals, six exhibited sight as evidenced by robust optokinetic and volitional visual behaviors. Electroretinographic responses, absent in untreated animals, were partially restored in treated animals. Morphological analyses indicated there was slowing of the retinal degeneration.Blindness associated with loss of function of retGC1 in the GUCY1*B avian model of LCA1 can be reversed using viral vector-mediated gene transfer. Furthermore, this reversal can be achieved by restoring function to a relatively low percentage of retinal photoreceptors. These results represent a first step toward development of gene therapies for one of the more common forms of childhood blindness.

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.

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.

Individual differences in change blindness

OpenAIRE

Bergmann, Katharina Verena

2016-01-01

The present work shows the existence of systematic individual differences in change blindness. It can be concluded that the sensitivity for changes is a trait. That is, persons differ in their ability to detect changes, independent from the situation or the measurement method. Moreover, there are two explanations for individual differences in change blindness: a) capacity differences in visual selective attention that may be influenced by top-down activated attention helping to focus attentio...

Spared cognitive processing of visual oddballs despite delayed visual evoked potentials in patient with partial recovery of vision after 53 years of blindness

Czech Academy of Sciences Publication Activity Database

Kremláček, J.; Šikl, Radovan; Kuba, M.; Szanyi, J.; Kubová, Z.; Langrová, J.; Vít, F.; Šimeček, Michal; Stodůlka, P.

2013-01-01

Roč. 81, April (2013), s. 1-5 ISSN 0042-6989 R&D Projects: GA ČR(CZ) GAP407/12/2528 Institutional support: RVO:68081740 Keywords : visual deprivation * recovery from blindness * motion-onset VEPs * pattern-reversal VEPs * oddball ERPs * P3b Subject RIV: FH - Neurology Impact factor: 2.381, year: 2013 http://www.sciencedirect.com/science/article/pii/S0042698913000151

RUDO: A Home Ambient Intelligence System for Blind People.

Science.gov (United States)

Hudec, Milan; Smutny, Zdenek

2017-08-22

The article introduces an ambient intelligence system for blind people which besides providing assistance in home environment also helps with various situations and roles in which blind people may find themselves involved. RUDO, the designed system, comprises several modules that mainly support or ensure recognition of approaching people, alerting to other household members' movement in the flat, work on a computer, supervision of (sighted) children, cooperation of a sighted and a blind person (e.g., when studying), control of heating and zonal regulation by a blind person. It has a unified user interface that gives the blind person access to individual functions. The interface for blind people offers assistance with work on a computer, including writing in Braille on a regular keyboard and specialized work in informatics and electronics (e.g., programming). RUDO can complement the standard aids used by blind people at home, it increases their independence and creates conditions that allow them to become fully involved. RUDO also supports blind people sharing a home with sighted people, which contributes to their feeling of security and greater inclusion in society. RUDO has been implemented in a household for two years, which allows an evaluation of its use in practice.

Impact of color blindness on recognition of blood in body fluids.

Science.gov (United States)

Reiss, M J; Labowitz, D A; Forman, S; Wormser, G P

2001-02-12

Color blindness is a common hereditary X-linked disorder. To investigate whether color blindness affects the ability to detect the presence of blood in body fluids. Ten color-blind subjects and 20 sex- and age-matched control subjects were shown 94 photographs of stool, urine, or sputum. Frank blood was present in 57 (61%) of the photographs. Surveys were done to determine if board-certified internists had ever considered whether color blindness would affect detection of blood and whether an inquiry on color blindness was included in their standard medical interview. Color-blind subjects were significantly less able to identify correctly whether pictures of body fluids showed blood compared with non-color-blind controls (P =.001); the lowest rate of correct identifications occurred with pictures of stool (median of 26 [70%] of 37 for color-blind subjects vs 36.5 [99%] of 37 for controls; Pcolor-blind subjects were significantly less accurate than those with less severe color deficiency (P =.009). Only 2 (10%) of the 21 physicians had ever considered the possibility that color blindness might affect the ability of patients to detect blood, and none routinely asked their patients about color blindness. Color blindness impairs recognition of blood in body fluids. Color-blind individuals and their health care providers need to be made aware of this limitation.

Aetiology of blindness in Benin City, Nigeria | Omoti | Annals of ...

African Journals Online (AJOL)

The major causes of binocular blindness were cataract (34.4%), glaucoma (25%) and age related macula degeneration (8.59%). The main causes of uniocular blindness were cataract (23.79%), glaucoma (22.58%) and trauma (11.69%). Conclusion: Avoidable causes of blindness remain the leading causes of blindness ...

[Causes of blindness in students at the school for blind children in Ilvesheim. Changes between 1885 and 2008].

Science.gov (United States)

Rohrschneider, K; Mackensen, I

2013-04-01

Since 1868, the Department of Ophthalmology at the University of Heidelberg has been providing care for the pupils of the school for blind and visually handicapped children in Ilvesheim, Germany. Previous studies on the causes of low vision have demonstrated the effects of the advances in medicine and ophthalmology with an explicit decrease in the number of inflammatory corneal diseases, followed by a reduced number of students suffering from congenital cataract and glaucoma. The aim of the present study was to evaluate current data and to compare it to previous data. Ophthalmological data and additional disorders could be evaluated in 268 students visiting the special education school Schloßschule Ilvesheim between 2000 and 2008. The findings were compared to the results of previous studies concerning the degree of visual impairment and diagnosis. The children were divided according to German social law into blind, severely visually handicapped and visually handicapped. Out of the 268 students 83 (31.0%) were premature infants and 69 of these had additional disabilities, 130 were blind and 51 severely visually handicapped. Of the students 142 had additional learning, mental and/or motor handicaps. The most frequent cause of blindness or severe visual impairment was optic nerve atrophy (36.2 % and 37.3 %, respectively). The frequency of hereditary retinal diseases among the blind children was slightly higher with 24.6 % as compared to the data analysis from 1981 and was 15.7 % and 17.1 % among the severely visually handicapped and visually handicapped, respectively. Retinopathy of prematurity was diagnosed in approximately 20% of blind and severely visually handicapped children. As a result of the enormous advances of medical capabilities during the last decades the number of (formerly) premature infants has markedly increased. Most of these students are multiply handicapped and need extensive assistance. While the number of students suffering from hereditary

Design and Baseline Findings of a Multi-site Non-randomized Evaluation of the Effect of a Health Programme on Microfinance Clients in India

OpenAIRE

Saha, Somen

2013-01-01

Microfinance is the provision of financial services for the poor. Health program through microfinance has the potential to address several access barriers to health. We report the design and baseline findings of a multi-site non-randomized evaluation of the effect of a health program on the members of two microfinance organizations from Karnataka and Gujarat states of India. Villages identified for roll-out of health services with microfinance were pair-matched with microfinance only villages...

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

Science.gov (United States)

Chauvey, Valérie; Hatwell, Yvette; Verine, Bertrand; Kaminski, Gwenael; Gentaz, Edouard

2012-01-01

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. 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. 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 reflected in their cognition.

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

Visible-blind and solar-blind detection induced by defects in AlGaN high electron mobility transistors

Science.gov (United States)

Armstrong, Andrew M.; Klein, Brianna; Allerman, Andrew A.; Douglas, Erica A.; Baca, Albert G.; Crawford, Mary H.; Pickrell, Greg W.; Sanchez, Carlos A.

2018-03-01

Visible- and solar-blind detection was demonstrated using Al0.45Ga0.55N/Al0.30Ga0.70N and Al0.85Ga0.25N/Al0.70Ga0.30N high electron mobility transistors (HEMTs), respectively. Peak responsivities (S) of 3.9 × 106 A/W in the saturation mode and 6.2 × 104 A/W in the pinch-off mode were observed for the visible-blind Al0.45Ga0.55N/Al0.30Ga0.70N HEMT, and a peak S of 4.9 × 104 A/W was observed for the solar-blind Al0.85Ga0.15N/Al0.70Ga0.30N HEMT in the saturation mode. Spectrally resolved photocurrent investigation indicated that sub-bandgap absorption by defect states was the primary origin of the HEMTs' photoresponse. Defect-mediated responsivity caused slow photocurrent rise and fall times, but electrical pulsing was used to improve the bandwidth at the cost of optical gain. Operating HEMTs in this dynamic mode achieved a 25 Hz bandwidth with S = 2.9 × 105 A/W in accumulation and S = 2.0 × 104 A/W in pinch-off for visible-blind detection and S = 5.1 × 103 A/W for solar-blind detection.

Blind loop syndrome

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/001146.htm Blind loop syndrome To use the sharing features on ... Clinical Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David ...

Ask a Scientist: What is Color Blindness?

Science.gov (United States)

... video series. Dr. Sheldon Miller answers questions about color blindness, whether it can be treated, and how people ... an optical illusion? Click to Watch What is color blindness? Click to Watch How do I become a ...

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

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false A period of disability based on blindness..., SURVIVORS AND DISABILITY INSURANCE (1950- ) Determining Disability and Blindness Blindness § 404.1582 A period of disability based on blindness. If we find that you are blind and you meet the insured status...

Visual impairment and blindness in Hungary.

Science.gov (United States)

Szabó, Dorottya; Sándor, Gábor László; Tóth, Gábor; Pék, Anita; Lukács, Regina; Szalai, Irén; Tóth, Georgina Zsófia; Papp, András; Nagy, Zoltán Zsolt; Limburg, Hans; Németh, János

2018-03-01

The aim of this study was to estimate the prevalence and causes of blindness, severe visual impairment (SVI), moderate visual impairment (MVI), and early visual impairment (EVI) and its causes in an established market economy of Europe. A cross-sectional population-based survey. A sample size of 3675 was calculated using the standard Rapid Assessment of Avoidable Blindness (RAAB) software in Hungary. A total of 105 clusters of 35 people aged 50 years or older were randomly selected with probability proportionate to size by the Hungarian Central Statistical Office. Households within the clusters were selected using compact segment sampling. Visual acuity (VA) was assessed with a Snellen tumbling E-chart with or without a pinhole in the households. The adjusted prevalences of bilateral blindness, SVI, MVI and EVI were 0.9% (95% CI: 0.6-1.2), 0.5% (95% CI: 0.2-0.7), 5.1% (95% CI: 4.3-5.9) and 6.9% (95% CI: 5.9-7.9), respectively. The major causes of blindness in Hungary were age-related macular degeneration (AMD; 27.3%) and other posterior segment diseases (27.3%), cataract (21.2%) and glaucoma (12.1%). Cataract was the main cause of SVI, MVI and EVI. Cataract surgical coverage (CSC) was 90.7%. Of all bilateral blindness in Hungary, 45.5% was considered avoidable. This study proved that RAAB methodology can be successfully conducted in industrialized countries, which often lack reliable epidemiologic data. The prevalence of blindness was relatively low, with AMD and other posterior segment diseases being the leading causes, and cataract is still a significant cause of visual impairment. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

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…

Demonstration of measurement-only blind quantum computing

International Nuclear Information System (INIS)

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

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. (paper)

34 CFR 395.33 - Operation of cafeterias by blind vendors.

Science.gov (United States)

2010-07-01

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

Ask a Scientist: What is Color Blindness?

Medline Plus

Full Text Available ... series. Dr. Sheldon Miller answers questions about color blindness, whether it can be treated, and how people ... optical illusion? Click to Watch What is color blindness? Click to Watch How do I become a ...

Ask a Scientist: What is Color Blindness?

Medline Plus

Full Text Available ... Illusions Printables Ask a Scientist Video Series Why can’t you see colors well in the dark? ... Miller answers questions about color blindness, whether it can be treated, and how people become color blind. ...

Guidance-assist system for the blind

Science.gov (United States)

Farcy, Rene; Damaschini, Roland M.

2001-01-01

We propose navigational aid systems for the blind relying on active laser profilometry and infrared proximetry with a real time vibrotactile interface. The Teletact and the Vigitact are small hand held or badge worn devices to improve the spatial perception, the mobility and the security of blind people. The Teletact is a hand held laser telemeter and gives an accurate 3D spatial perception up to ten meters. The Vigitact is an infrared scanner and provides an automatic vigilance from knees to head up to two meters. Both devices are now commercially available. We will report on the basic functional parts of these devices, the results of everyday use by blind people, and future technological improvements.

Effects on peripheral and central blood pressure of cocoa with natural or high-dose theobromine: A randomized, double-blind crossover trial

OpenAIRE

Bogaard, Bas; Draijer, Richard; Westerhof, Berend; Meiracker, Anton; Montfrans, Gert; Born, B.J.H.

2010-01-01

textabstractFlavanol-rich cocoa products have been reported to lower blood pressure. It has been suggested that theobromine is partially responsible for this effect. We tested whether consumption of flavanol-rich cocoa drinks with natural or added theobromine could lower peripheral and central blood pressure. In a double-blind, placebo-controlled 3-period crossover trial we assigned 42 healthy individuals (age 62±4.5 years; 32 men) with office blood pressure of 130 to 159 mm Hg/85 to 99 mm Hg...

Simple pendulum for blind students

Science.gov (United States)

Goncalves, A. M. B.; Cena, C. R.; Alves, D. C. B.; Errobidart, N. C. G.; Jardim, M. I. A.; Queiros, W. P.

2017-09-01

Faced with the need to teach physics to the visually impaired, in this paper we propose a way to demonstrate the dependence of distance and time in a pendulum experiment to blind students. The periodic oscillation of the pendulum is translated, by an Arduino and an ultrasonic sensor, in a periodic variation of frequency in a speaker. The main advantage of this proposal is the possibility that a blind student understands the movement without necessity of touching it.

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...

Ask a Scientist: What is Color Blindness?

Medline Plus

Full Text Available ... the special health problems and requirements of the blind.” News & Events Events Calendar NEI Press Releases News ... series. Dr. Sheldon Miller answers questions about color blindness, whether it can be treated, and how people ...

Universal blind quantum computation for hybrid system

Science.gov (United States)

Huang, He-Liang; Bao, Wan-Su; Li, Tan; Li, Feng-Guang; Fu, Xiang-Qun; Zhang, Shuo; Zhang, Hai-Long; Wang, Xiang

2017-08-01

As progress on the development of building quantum computer continues to advance, first-generation practical quantum computers will be available for ordinary users in the cloud style similar to IBM's Quantum Experience nowadays. Clients can remotely access the quantum servers using some simple devices. In such a situation, it is of prime importance to keep the security of the client's information. Blind quantum computation protocols enable a client with limited quantum technology to delegate her quantum computation to a quantum server without leaking any privacy. To date, blind quantum computation has been considered only for an individual quantum system. However, practical universal quantum computer is likely to be a hybrid system. Here, we take the first step to construct a framework of blind quantum computation for the hybrid system, which provides a more feasible way for scalable blind quantum computation.

Radiation Protection, double-blind studies with radiopharmaceuticals

International Nuclear Information System (INIS)

Pujadas, M. C.; Camacho, C.; Guasp, M.; Villaescusa, J. I.

2009-01-01

In a double-blind randomized controlled clinical trial (RCT) subjects and researchers do not know the assignment to treatment groups to ovoid the appearance of subjective biases of information. The employment of radiopharmaceuticals in double-blind RCTs raises a dilemma from the point ov view of the radiological protection. On the one hand, the obligation to act in cases of contamination and/or risk of irradiation exists, but on the other hand the duty of keeping the blind study also exists. In this paper some of the possible problems that arise when conducting a double-blind RCT with radiopharmaceuticals from the point of view of the radiological protection are presented. We comment our experience with the radiopharmaceutical Alpharadin and, in addition, we propose useful recommendations based on the randomness of the decontamination process. (Author) 7 refs.

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.

Motion-Dependent Filling-In of Spatiotemporal Information at the Blind Spot.

Science.gov (United States)

Maus, Gerrit W; Whitney, David

2016-01-01

We usually do not notice the blind spot, a receptor-free region on the retina. Stimuli extending through the blind spot appear filled in. However, if an object does not reach through but ends in the blind spot, it is perceived as "cut off" at the boundary. Here we show that even when there is no corresponding stimulation at opposing edges of the blind spot, well known motion-induced position shifts also extend into the blind spot and elicit a dynamic filling-in process that allows spatial structure to be extrapolated into the blind spot. We presented observers with sinusoidal gratings that drifted into or out of the blind spot, or flickered in counterphase. Gratings moving into the blind spot were perceived to be longer than those moving out of the blind spot or flickering, revealing motion-dependent filling-in. Further, observers could perceive more of a grating's spatial structure inside the blind spot than would be predicted from simple filling-in of luminance information from the blind spot edge. This is evidence for a dynamic filling-in process that uses spatiotemporal information from the motion system to extrapolate visual percepts into the scotoma of the blind spot. Our findings also provide further support for the notion that an explicit spatial shift of topographic representations contributes to motion-induced position illusions.

Ask a Scientist: What is Color Blindness?

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Full Text Available ... video series. Dr. Sheldon Miller answers questions about color blindness, whether it can be treated, and how people ... an optical illusion? Click to Watch What is color blindness? Click to Watch How do I become a ...

Ask a Scientist: What is Color Blindness?

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Full Text Available ... blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health problems and requirements of the blind.” ... DeMott, Media Relations Kathryn.DeMott@nih.gov NEI Office of Communications ( ...

Recurrent Partial Words

Directory of Open Access Journals (Sweden)

Francine Blanchet-Sadri

2011-08-01

Full Text Available Partial words are sequences over a finite alphabet that may contain wildcard symbols, called holes, which match or are compatible with all letters; partial words without holes are said to be full words (or simply words. Given an infinite partial word w, the number of distinct full words over the alphabet that are compatible with factors of w of length n, called subwords of w, refers to a measure of complexity of infinite partial words so-called subword complexity. This measure is of particular interest because we can construct partial words with subword complexities not achievable by full words. In this paper, we consider the notion of recurrence over infinite partial words, that is, we study whether all of the finite subwords of a given infinite partial word appear infinitely often, and we establish connections between subword complexity and recurrence in this more general framework.

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 of...

Identifying Autism in Children with Blindness and Visual Impairments.

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Gense, Marilyn H.; Gense, D. Jay

1994-01-01

This paper offers guidelines to compare the characteristics observed in children with autism and blindness and those observed in children with blindness alone. It distinguishes between stereotypic behaviors (blindisms) in blind individuals and similar stereotypic behaviors of children with autism. A table presents typical behavior patterns of…

A Weak Quantum Blind Signature with Entanglement Permutation

Science.gov (United States)

Lou, Xiaoping; Chen, Zhigang; Guo, Ying

2015-09-01

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

Blind Ambition

Science.gov (United States)

Olson, Catherine Applefeld

2009-01-01

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

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.

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…

Patient satisfaction with laser-sintered removable partial dentures: A crossover pilot clinical trial.

Science.gov (United States)

Almufleh, Balqees; Emami, Elham; Alageel, Omar; de Melo, Fabiana; Seng, Francois; Caron, Eric; Nader, Samer Abi; Al-Hashedi, Ashwaq; Albuquerque, Rubens; Feine, Jocelyne; Tamimi, Faleh

2018-04-01

Clinical data regarding newly introduced laser-sintered removable partial dentures (RPDs) are needed before this technique can be recommended. Currently, only a few clinical reports have been published, with no clinical studies. This clinical trial compared short-term satisfaction in patients wearing RPDs fabricated with conventional or computer-aided design and computer-aided manufacturing (CAD-CAM) laser-sintering technology. Twelve participants with partial edentulism were enrolled in this pilot crossover double-blinded clinical trial. Participants were randomly assigned to wear cast or CAD-CAM laser-sintered RPDs for alternate periods of 30 days. The outcome of interest was patient satisfaction as measured using the McGill Denture Satisfaction Instrument. Assessments was conducted at 1, 2, and 4 weeks. The participant's preference in regard to the type of prosthesis was assessed at the final evaluation. The linear mixed effects regression models for repeated measures were used to analyze the data, using the intention-to-treat principle. To assess the robustness of potential, incomplete adherence, sensitivity analyses were conducted. Statistically significant differences were found in patients' satisfaction between the 2 methods of RPD fabrication. Participants were significantly more satisfied with laser-sintered prostheses than cast prostheses in regard to general satisfaction, ability to speak, ability to clean, comfort, ability to masticate, masticatory efficiency, and oral condition (Premovable partial dentures may lead to better outcomes in terms of patient satisfaction in the short term. The conclusion from this pilot study requires confirmation by a larger randomized controlled trial. ClinicalTrials.gov. A study about patient satisfaction with laser-sintered removable partial dentures; NCT02769715. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Working memory and inattentional blindness.

Science.gov (United States)

Bredemeier, Keith; Simons, Daniel J

2012-04-01

Individual differences in working memory predict many aspects of cognitive performance, especially for tasks that demand focused attention. One negative consequence of focused attention is inattentional blindness, the failure to notice unexpected objects when attention is engaged elsewhere. Yet, the relationship between individual differences in working memory and inattentional blindness is unclear; some studies have found that higher working memory capacity is associated with greater noticing, but others have found no direct association. Given the theoretical and practical significance of such individual differences, more definitive tests are needed. In two studies with large samples, we tested the relationship between multiple working memory measures and inattentional blindness. Individual differences in working memory predicted the ability to perform an attention-demanding tracking task, but did not predict the likelihood of noticing an unexpected object present during the task. We discuss the reasons why we might not expect such individual differences in noticing and why other studies may have found them.

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…

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.

The global state of cataract blindness.

Science.gov (United States)

Lee, Cameron M; Afshari, Natalie A

2017-01-01

Cataracts are a significant cause of blindness and visual impairment worldwide. The present article reviews the literature and describes the current extent of cataracts globally, barriers to treatment, and recommendations for improving the treatment of cataracts. Prevalence and absolute number of blind because of cataracts remain high, although rates are declining in many areas globally. The age-standardized prevalence of blindness in adults older than 50 remains highest in western sub-Saharan Africa, with a rate of 6.0%. The greatest declines in age-standardized blindness because of cataracts in adults older than 50 between 1990 and 2010 were in East Asia, tropical Latin America, and western Europe. Recent studies have largely found higher rates of cataracts in women than in men. A new simulator for training ophthalmologists in manual small-incision cataract surgery holds promise for the future. The rates of cataract surgery are increasing and postoperative outcomes are improving worldwide, yet challenges to reducing the cataract burden further remain. Cost, an insufficient number of ophthalmologists, and low government funding remain significant barriers but investment in further eye care infrastructure and training of additional ophthalmologists would improve the current situation.

Vision after 53 years of blindness.

Science.gov (United States)

Sikl, Radovan; Simecček, Michal; Porubanová-Norquist, Michaela; Bezdíček, Ondřej; Kremláček, Jan; Stodůlka, Pavel; Fine, Ione; Ostrovsky, Yuri

2013-01-01

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.

Wavelet Coherence Analysis of Change Blindness

Directory of Open Access Journals (Sweden)

Irfan Ali Memon

2013-01-01

Full Text Available 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.

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.

Wavelet coherence analysis of change blindness

International Nuclear Information System (INIS)

Memon, I.; Kalhoro, M.S.

2013-01-01

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)

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

Science.gov (United States)

Isipradit, Saichin; Sirimaharaj, Maytinee; Charukamnoetkanok, Puwat; Thonginnetra, Oraorn; Wongsawad, Warapat; Sathornsumetee, Busaba; Somboonthanakij, Sudawadee; Soomsawasdi, Piriya; Jitawatanarat, Umapond; Taweebanjongsin, Wongsiri; Arayangkoon, Eakkachai; Arame, Punyawee; Kobkoonthon, Chinsuchee; Pangputhipong, Pannet

2014-01-01

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. 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. The age and sex adjusted prevalence of blindness (presenting visual acuity (VA) 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. 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.

Blind Loop Syndrome

Science.gov (United States)

... or scleroderma involving the small intestine History of radiation therapy to the abdomen Diabetes Diverticulosis of the small intestine Complications A blind loop can cause escalating problems, including: Poor absorption of fats. Bacteria in your small intestine break down the bile ...

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 are...

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.

Vincristine-induced blindness: a case report and review of literature.

Science.gov (United States)

Adhikari, Subodh; Dongol, Raj Man; Hewett, Yvonne; Shah, Binay Kumar

2014-11-01

Neurotoxicity is a dose-limiting side-effect of vincristine therapy. Blindness is a rare central neurotoxicity of vincristine with few case reports. In the present article, we report a rare case of vincristine-induced blindness in a patient with diffuse large B cell lymphoma. Literature search identified eleven published cases of vincristine-induced blindness. We reviewed patient characteristics, chemotherapy used and type of blindness. Vincristine-induced blindness is rare and unpredictable. Prompt recognition and discontinuation of vincristine may lead to recovery of vision. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Find Services for People Who Are Blind or Visually Impaired

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... Are Blind or Visually Impaired Find Services for People Who Are Blind or Visually Impaired Category All ... Territory Other (International) Organization Name Find Services for People Who Are Blind or Visually Impaired Browse All ...

Spatial navigation by congenitally blind individuals

OpenAIRE

Schinazi, Victor R.; Thrash, Tyler; Chebat, Daniel?Robert

2015-01-01

Spatial navigation in the absence of vision has been investigated from a variety of perspectives and disciplines. These different approaches have progressed our understanding of spatial knowledge acquisition by blind individuals, including their abilities, strategies, and corresponding mental representations. In this review, we propose a framework for investigating differences in spatial knowledge acquisition by blind and sighted people consisting of three longitudinal models (i.e., convergen...

Hypnotic color blindness and performance on the Stroop test.

Science.gov (United States)

Mallard, D; Bryant, R A

2001-10-01

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

Causes of low vision and blindness in rural Indonesia

Science.gov (United States)

Saw, S-M; Husain, R; Gazzard, G M; Koh, D; Widjaja, D; Tan, D T H

2003-01-01

Aim: To determine the prevalence rates and major contributing causes of low vision and blindness in adults in a rural setting in Indonesia Methods: A population based prevalence survey of adults 21 years or older (n=989) was conducted in five rural villages and one provincial town in Sumatra, Indonesia. One stage household cluster sampling procedure was employed where 100 households were randomly selected from each village or town. Bilateral low vision was defined as habitual VA (measured using tumbling “E” logMAR charts) in the better eye worse than 6/18 and 3/60 or better, based on the WHO criteria. Bilateral blindness was defined as habitual VA worse than 3/60 in the better eye. The anterior segment and lens of subjects with low vision or blindness (both unilateral and bilateral) (n=66) were examined using a portable slit lamp and fundus examination was performed using indirect ophthalmoscopy. Results: The overall age adjusted (adjusted to the 1990 Indonesia census population) prevalence rate of bilateral low vision was 5.8% (95% confidence interval (CI) 4.2 to 7.4) and bilateral blindness was 2.2% (95% CI 1.1 to 3.2). The rates of low vision and blindness increased with age. The major contributing causes for bilateral low vision were cataract (61.3%), uncorrected refractive error (12.9%), and amblyopia (12.9%), and the major cause of bilateral blindness was cataract (62.5%). The major causes of unilateral low vision were cataract (48.0%) and uncorrected refractive error (12.0%), and major causes of unilateral blindness were amblyopia (50.0%) and trauma (50.0%). Conclusions: The rates of habitual low vision and blindness in provincial Sumatra, Indonesia, are similar to other developing rural countries in Asia. Blindness is largely preventable, as the major contributing causes (cataract and uncorrected refractive error) are amenable to treatment. PMID:12928268

Detecting Blind Spot By Using Ultrasonic Sensor

Directory of Open Access Journals (Sweden)

T. S. Ajay

2015-08-01

Full Text Available Safety remains a top concern for automobile industries and new-car shoppers. Detection of Blind Spots is a major concern for safety issues. So automobiles have been constantly updating their products with new technologies to detect blind spots so that they can add more safety to the vehicle and also reduce the road accidents. Almost 1.5 million people die in road accidents each year. Blind spot of an automobile is the region of the vehicle which cannot be observed properly while looking either through side or rear mirror view. To meet the above requirements this paper describes detecting blind spot by using ultrasonic sensor and controlling the direction of car by automatic steering. The technology embedded in the system is capable of automatically steer the vehicle away from an obstacle if the system determines that a collision is impending or if the vehicle is in the vicinity of our car.

Causes of Blindness in a Special Education School | Onakpoya ...

African Journals Online (AJOL)

All students in the blind section were examined for visual acuity, pen-torch eye examination and dilated fundoscopy in addition to taking biodata and history. RESULTS: Thirty blind students with mean age of 18±7.3 years and male: female ratio of 1.7:1 were examined. Blindness resulted commonly from cataract eight ...

The effects of the Bali Yoga Program (BYP-BC) on reducing psychological symptoms in breast cancer patients receiving chemotherapy: results of a randomized, partially blinded, controlled trial.

Science.gov (United States)

Lanctôt, Dominique; Dupuis, Gilles; Marcaurell, Roger; Anestin, Annélie S; Bali, Madan

2016-12-01

Background Several cognitive behavioral interventions have been reported to reduce psychological symptoms in breast cancer (BC) patients. The goal of this study was to evaluate the effects of a yoga intervention in reducing depression and anxiety symptoms in BC patients. Methods This study was a randomized, partially blinded, controlled trial comparing a standardized yoga intervention to standard care. It was conducted at three medical centers in Montreal, Canada. Eligible patients were women diagnosed with stage I-III BC receiving chemotherapy. Participants were randomly assigned to receive yoga intervention immediately (experimental group, n=58) or after a waiting period (n=43 control group). The Bali Yoga Program for Breast Cancer Patients (BYP-BC) consisted of 23 gentle Hatha asanas (poses), 2 prayanamas (breathing techniques), shavasanas (relaxation corpse poses) and psychoeducational themes. Participants attended eight weekly sessions lasting 90 min each and received a DVD for home practice with 20- and 40-min sessions. Participants in the wait list control group received standard care during the 8-week waiting period. Results A total of 101 participants took part in the final intention-to-treat analyses. The repeated measures analyses demonstrated that depression symptoms increased in the control group (p=0.007), while no change was reported in the BYP-BC group (p=0.29). Also, depression symptoms decreased in the WL control group after receiving the BYP-BC intervention (p=0.03). Finally, there was no statistical significance in terms of anxiety symptoms (p=0.10). Conclusions Results support the BYP-BC intervention as a beneficial means of reducing and preventing the worsening of depression symptoms during chemotherapy treatment.

Milestones on the road to independence for the blind

Science.gov (United States)

Reed, Kenneth

1997-02-01

Ken will talk about his experiences as an end user of technology. Even moderate technological progress in the field of pattern recognition and artificial intelligence can be, often surprisingly, of great help to the blind. An example is the providing of portable bar code scanners so that a blind person knows what he is buying and what color it is. In this age of microprocessors controlling everything, how can a blind person find out what his VCR is doing? Is there some technique that will allow a blind musician to convert print music into midi files to drive a synthesizer? Can computer vision help the blind cross a road including predictions of where oncoming traffic will be located? Can computer vision technology provide spoken description of scenes so a blind person can figure out where doors and entrances are located, and what the signage on the building says? He asks 'can computer vision help me flip a pancake?' His challenge to those in the computer vision field is 'where can we go from here?'

Calendar systems and communication of deaf-blind children

OpenAIRE

Jablan Branka; Stanimirov Ksenija

2012-01-01

The aim of this paper is to explain the calendar systems and their role in teaching deaf-blind children. Deaf-blind persons belong to a group of multiple disabled persons. This disability should not be observed as a simple composite of visual and hearing impairments, but as a combination of sensory impairments that require special assistance in the development, communication and training for independent living. In our environment, deaf-blind children are being educated in schools for children...

Parallelization of a blind deconvolution algorithm

Science.gov (United States)

Matson, Charles L.; Borelli, Kathy J.

2006-09-01

Often it is of interest to deblur imagery in order to obtain higher-resolution images. Deblurring requires knowledge of the blurring function - information that is often not available separately from the blurred imagery. Blind deconvolution algorithms overcome this problem by jointly estimating both the high-resolution image and the blurring function from the blurred imagery. Because blind deconvolution algorithms are iterative in nature, they can take minutes to days to deblur an image depending how many frames of data are used for the deblurring and the platforms on which the algorithms are executed. Here we present our progress in parallelizing a blind deconvolution algorithm to increase its execution speed. This progress includes sub-frame parallelization and a code structure that is not specialized to a specific computer hardware architecture.

The blind student’s interpretation of two-dimensional shapes in geometry

Science.gov (United States)

Andriyani; Budayasa, I. K.; Juniati, D.

2018-01-01

The blind student’s interpretation of two-dimensional shapes represents the blind student’s mental image of two-dimensional shapes that they can’t visualize directly, which is related to illustration of the characteristics and number of edges and angles. The objective of this research is to identify the blind student’s interpretation of two-dimensional shapes. This research was an exploratory study with qualitative approach. A subject of this research is a sixth-grade student who experiencing total blind from the fifth grade of elementary school. Researchers interviewed the subject about his interpretation of two-dimensional shapes according to his thinking.The findings of this study show the uniqueness of blind students, who have been totally blind since school age, in knowing and illustrating the characteristics of edges and angles of two-dimensional shapes by utilizing visual experiences that were previously obtained before the blind. The result can inspire teachers to design further learning for development of blind student geometry concepts.

A survey of visual impairment and blindness in children attending four schools for the blind in Cambodia.

Science.gov (United States)

Sia, David I T; Muecke, James; Hammerton, Michael; Ngy, Meng; Kong, Aimee; Morse, Anna; Holmes, Martin; Piseth, Horm; Hamilton, Carolyn; Selva, Dinesh

2010-08-01

To identify the causes of blindness and severe visual impairment (BL/SVI) in children attending four schools for the blind in Cambodia and to provide spectacles, low vision aids, orientation and mobility training and ophthalmic treatment. Children schools for the blind in Cambodia. Causes of visual impairment and blindness were determined and categorized using World Health Organization methods. Of the 95 children examined, 54.7% were blind (BL) and 10.5% were severely visually impaired (SVI). The major anatomical site of BL/SVI was the lens in 27.4%, cornea in 25.8%, retina in 21% and whole globe in 17.7%. The major underlying etiologies of BL/SVI were hereditary factors (mainly cataract and retinal dystrophies) in 45.2%, undetermined/unknown (mainly microphthalmia and anterior segment dysgenesis) in 38.7% and childhood factors in 11.3%. Avoidable causes of BL/SVI accounted for 50% of the cases; 12.9% of the total were preventable with measles being the commonest cause (8.1% of the total); 37.1% were treatable with cataracts and glaucoma being the commonest causes (22.6% and 4.8% respectively). More than 35% of children required an optical device and 27.4% had potential for visual improvement with intervention. Half of the BL/SVI causes were potentially avoidable. The data support the need for increased coverage of measles immunization. There is also a need to develop specialized pediatric ophthalmic services for the management of surgically remediable conditions, to provide optometric, low vision and orientation and mobility services. Genetic risk counseling services also may be considered.

Prevalence and Causes of Blindness in Ikwerre Local Government ...

African Journals Online (AJOL)

Alasia Datonye

treated or even prevented from occurring. ... prevention of blindness. ... The prevalence of blindness for Nigeria is 1.0% and 0.7% .... Age is confirmed as a risk factor for developing glaucoma in this study since all those blinded by glaucoma were over 50 year ... in a 78year old woman and macular degeneration in a 69 year.

A Taxonomy for Mannerisms of Blind Children.

Science.gov (United States)

Eichel, Valerie J.

1979-01-01

The investigation involving 24 blind children (2-11 years old) set out to develop and validate a coding procedure which employed a set of 34 descriptors with their corresponding definitions. The use of the taxonomy enabled a detailed, systematic study of manneristic behavior in blind children. (Author/SBH)

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…

The relationship between sustained inattentional blindness and working memory capacity.

Science.gov (United States)

Beanland, Vanessa; Chan, Esther Hiu Chung

2016-04-01

Inattentional blindness, whereby observers fail to detect unexpected stimuli, has been robustly demonstrated in a range of situations. Originally research focused primarily on how stimulus characteristics and task demands affect inattentional blindness, but increasingly studies are exploring the influence of observer characteristics on the detection of unexpected stimuli. It has been proposed that individual differences in working memory capacity predict inattentional blindness, on the assumption that higher working memory capacity confers greater attentional capacity for processing unexpected stimuli. Unfortunately, empirical investigations of the association between inattentional blindness and working memory capacity have produced conflicting findings. To help clarify this relationship, we examined the relationship between inattentional blindness and working memory capacity in two samples (Ns = 195, 147) of young adults. We used three common variants of sustained inattentional blindness tasks, systematically manipulating the salience of the unexpected stimulus and primary task practice. Working memory capacity, measured by automated operation span (both Experiments 1 & 2) and N-back (Experiment 1 only) tasks, did not predict detection of the unexpected stimulus in any of the inattentional blindness tasks tested. Together with previous research, this undermines claims that there is a robust relationship between inattentional blindness and working memory capacity. Rather, it appears that any relationship between inattentional blindness and working memory is either too small to have practical significance or is moderated by other factors and consequently varies with attributes such as the sample characteristics within a given study.

Improved system blind identification based on second-order ...

Indian Academy of Sciences (India)

An improved system blind identification method based on second- order cyclostationary statistics and the properties of group delay, has been ... In the last decade, there has been considerable research on achieving blind identification.

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.

20 CFR 404.1581 - 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..., SURVIVORS AND DISABILITY INSURANCE (1950- ) Determining Disability and Blindness Blindness § 404.1581 Meaning of blindness as defined in the law. We will consider you blind under the law for a period of...

Gender-Blind Sexism and Rape Myth Acceptance.

Science.gov (United States)

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

2017-01-01

The purpose of this article is to explore whether gender-blind sexism, as an extension of Bonilla-Silva's racialized social system theory, is an appropriate theoretical framework for understanding the creation and continued prevalence of rape myth acceptance. Specifically, we hypothesize that individuals who hold attitudes consistent with the frames of gender-blind sexism are more likely to accept common rape myths. Data for this article come from an online survey administered to the entire undergraduate student body at a large Midwestern institution (N = 1,401). Regression analysis showed strong support for the effects of gender-blind sexism on rape myth acceptance. © The Author(s) 2016.

Differences between early-blind, late-blind, and blindfolded-sighted people in haptic spatial-configuration learning and resulting memory traces

NARCIS (Netherlands)

Postma, Albert; Zuidhoek, Sander; Noordzij, Matthijs L.; Kappers, Astrid M L

2007-01-01

The roles of visual and haptic experience in different aspects of haptic processing of objects in peripersonal space are examined. In three trials, early-blind, late-blind, and blindfoldedsighted individuals had to match ten shapes haptically to the cut-outs in a board as fast as possible. Both

Task-irrelevant memory load induces inattentional blindness without temporo-parietal suppression.

Science.gov (United States)

Matsuyoshi, Daisuke; Ikeda, Takashi; Sawamoto, Nobukatsu; Kakigi, Ryusuke; Fukuyama, Hidenao; Osaka, Naoyuki

2010-08-01

We often fail to consciously detect an unexpected object when we are engaged in an attention-demanding task (inattentional blindness). The inattentional blindness which is induced by visual short-term memory (VSTM) load has been proposed to result from a suppression of temporo-parietal junction (TPJ) activity that involves stimulus-driven attention. However, the fact that, inversely proportional to TPJ activity, intraparietal sulcus (IPS) activity correlates with VSTM load renders questionable the account of inattentional blindness based only on TPJ activity. Here, we investigated whether the TPJ is solely responsible for inattentional blindness by decoupling IPS and TPJ responses to VSTM load and then using the same manipulation to test the behavioral inattentional blindness performance. Experiment 1 showed that TPJ activity was not suppressed by task-irrelevant load while the IPS responded to both task-relevant and task-irrelevant load. Although the TPJ account of inattentional blindness predicts that the degree of inattentional blindness should track TPJ activity, we found in Experiment 2 that inattentional blindness was induced not only by task-relevant load but also by task-irrelevant load, showing inconsistency between the extent of inattentional blindness and TPJ response. These findings suggest that inattentional blindness can be induced without suppression of TPJ activity and seem to offer the possibility that the IPS contributes to conscious perception. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

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 ...

Ultrasonographic Evaluation of Zone II Partial Flexor Tendon Lacerations of the Fingers: A Cadaveric Study.

Science.gov (United States)

Kazmers, Nikolas H; Gordon, Joshua A; Buterbaugh, Kristen L; Bozentka, David J; Steinberg, David R; Khoury, Viviane

2018-04-01

Accurate assessment of zone II partial flexor tendon lacerations in the finger is clinically important. Surgical repair is recommended for lacerations of greater than 50% to 60%. Our goal was to evaluate ultrasonographic test characteristics and accuracy in identifying partial flexor tendon lacerations in a cadaveric model. From fresh-frozen above-elbow human cadaveric specimens, 32 flexor digitorum profundus tendons were randomly selected to remain intact or receive low- or high-grade lacerations involving 10% to 40% and 60% to 90% of the radioulnar width within Verdan Zone II, respectively. Static and dynamic ultrasonography using a linear array 14-MHz transducer was performed by a blinded musculoskeletal radiologist. Sensitivities, specificities, and other standard test performance metrics were calculated. Actual and measured percentages of tendon laceration were compared by the paired t test. After randomization, 24 tendons were lacerated (12 low- and 12 high-grade), whereas 8 remained intact. The sensitivity and specificity in detecting the presence versus absence of a partial laceration were 0.54 and 0.75, respectively, with positive and negative likelihood ratio values of 2.17 and 0.61. For low-grade lacerations, the sensitivity and specificity were 0.25 and 0.85, compared to 0.83 and 0.85 for high-grade lacerations. Ultrasonography underestimated the percentage of tendon involvement by a mean of 18.1% for the study population as a whole (95% confidence interval, 9.0% to 27.2%; P partial flexor digitorum profundus lacerations in a cadaveric model. © 2017 by the American Institute of Ultrasound in Medicine.

Overview on Deaf-Blindness

Science.gov (United States)

... of Deaf-Blind Education Transition to Adulthood > Transition Self Determination Person Centered Planning Postsecondary Education Independent Living Employment Customized Employment Sex Education Adult Services Technology Personnel > Intervener Services Support ...

the common causes of blindness in north western nigeria

African Journals Online (AJOL)

at 3m), with or without light perception and/or central visual field of less than 10 . Legal blindness can ... (9.5%), trauma (6.7%), staphyloma (3.6%) and refractive error (1.5%). Blindness is a significant burden to society in that the cost ... for the sample, and this was followed by POAG. (10.7%). Blindness due to refractive error.

Justifications shape ethical blind spots.

Science.gov (United States)

Pittarello, Andrea; Leib, Margarita; Gordon-Hecker, Tom; Shalvi, Shaul

2015-06-01

To some extent, unethical behavior results from people's limited attention to ethical considerations, which results in an ethical blind spot. Here, we focus on the role of ambiguity in shaping people's ethical blind spots, which in turn lead to their ethical failures. We suggest that in ambiguous settings, individuals' attention shifts toward tempting information, which determines the magnitude of their lies. Employing a novel ambiguous-dice paradigm, we asked participants to report the outcome of the die roll appearing closest to the location of a previously presented fixation cross on a computer screen; this outcome would determine their pay. We varied the value of the die second closest to the fixation cross to be either higher (i.e., tempting) or lower (i.e., not tempting) than the die closest to the fixation cross. Results of two experiments revealed that in ambiguous settings, people's incorrect responses were self-serving. Tracking participants' eye movements demonstrated that people's ethical blind spots are shaped by increased attention toward tempting information. © The Author(s) 2015.

20 CFR 404.1503 - 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..., SURVIVORS AND DISABILITY INSURANCE (1950- ) Determining Disability and Blindness Determinations § 404.1503 Who makes disability and blindness determinations. (a) State agencies. State agencies make disability...

Causes of severe visual impairment and blindness in children in schools for the blind in eastern Africa: changes in the last 14 years.

Science.gov (United States)

Njuguna, Margaret; Msukwa, Gerald; Shilio, Bernadeth; Tumwesigye, Cillasy; Courtright, Paul; Lewallen, Susan

2009-01-01

To determine the causes of severe visual impairment and blindness in children attending schools for the blind in Kenya, Malawi, Uganda, and Tanzania and to compare the findings with those of a 1994 study. Children attending schools for the blind or annexes in 4 eastern African countries were examined. The major anatomical site of and underlying etiology of severe visual impairment and blindness was recorded using the standardized World Health Organization (WHO) reporting form. A total of 1062 children aged below 16 years were examined of whom 701 (65.2%) had severe visual impairment or blindness. The major anatomical sites of visual loss overall (% and 95% CI) were cornea scar/phthisis bulbi (19%,16.1-21.9), whole globe lesions (15.7%,13.0-18.4), retina (15.4 %, 12.7-18.1), lens related disorders (13.1%, 10.7-15.5), and optic nerve disorders (12.3%, 9.9-14.7). Corneal scar/phthisis was not distributed equally among the countries and was highest in Malawi, similar to findings in 1995. The major etiology of visual loss was childhood factors (29.9%) and an estimated 40% of severe visual impairment and blindness was due to potentially avoidable causes. The major causes of severe visual impairment and blindness overall have not changed appreciably since 1995. There are important differences among countries, however, and using overall estimates for planning may be misleading.

Partial tooth gear bearings

Science.gov (United States)

Vranish, John M. (Inventor)

2010-01-01

A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.

Classroom-based narrative and vocabulary instruction: results of an early-stage, nonrandomized comparison study.

Science.gov (United States)

Gillam, Sandra Laing; Olszewski, Abbie; Fargo, Jamison; Gillam, Ronald B

2014-07-01

This nonrandomized feasibility study was designed to provide a preliminary assessment of the impact of a narrative and vocabulary instruction program provided by a speech-language pathologist (SLP) in a regular classroom setting. Forty-three children attending 2 first-grade classrooms participated in the study. Children in each classroom were divided into high- and low-risk subgroups on the basis of their performance on a narrative test. Narrative and vocabulary instruction was provided by an SLP in 1 classroom for three 30-min periods per week for 6 weeks. The children in the experimental classroom made clinically significant improvements on narrative and vocabulary measures; children in the comparison classroom did not. Within the experimental classroom, children in the high-risk subgroup demonstrated greater gains in narration and fewer gains in vocabulary than children in the low-risk subgroup. There were no subgroup differences in the comparison classroom. These preliminary results provide early evidence of the feasibility of implementing a narrative instruction program in a classroom setting. Children at a high risk for language difficulties appeared to profit more from the narrative instruction than from the embedded vocabulary instruction. More extensive research on this instructional program is warranted.

Odour discrimination and identification are improved in early blindness.

Science.gov (United States)

Cuevas, Isabel; Plaza, Paula; Rombaux, Philippe; De Volder, Anne G; Renier, Laurent

2009-12-01

Previous studies showed that early blind humans develop superior abilities in the use of their remaining senses, hypothetically due to a functional reorganization of the deprived visual brain areas. While auditory and tactile functions have been investigated for long, little is known about the effects of early visual deprivation on olfactory processing. However, blind humans make an extensive use of olfactory information in their daily life. Here we investigated olfactory discrimination and identification abilities in early blind subjects and age-matched sighted controls. Three levels of cuing were used in the identification task, i.e., free-identification (no cue), categorization (semantic cues) and multiple choice (semantic and phonological cues). Early blind subjects significantly outperformed the controls in odour discrimination, free-identification and categorization. In addition, the larger group difference was observed in the free-identification as compared to the categorization and the multiple choice conditions. This indicated that a better access to the semantic information from odour perception accounted for part of the improved olfactory performances in odour identification in the blind. We concluded that early blind subjects have both improved perceptual abilities and a better access to the information stored in semantic memory than sighted subjects.

Treatment of age-related subfoveal neovascular membranes by teletherapy. Results of a non-randomized study

Energy Technology Data Exchange (ETDEWEB)

Subasi, M.; Akmansu, M.; Or, M. [Gazi Univ., Ankara (Turkey). Medical Faculty

1999-03-01

This investigation was designed to determine whether low-dose radiation to the macular region could influence the natural course of age-related subfoveal neovascularization. Thirty-one patients with subfoveal membranes due to age-related macular degeneration (ARMD) were treated with 12 Gy of 6 MV X-rays, and 72 patients who were untreated served as a control group. Both groups were followed-up. At six months of follow-up visual acuity was maintained in 54.8% and improved 25.8% of patients treated by radiotherapy. In the control group, visual acuity showed deterioration in 55.5%. There was a significant difference between the treated and untreated groups (p<0.01). Significant neovascular membrane regression or stabilization was recorded in 61.3% of treated patients at six months post-radiation, whereas the membranes in all. 72 control patients showed progressive enlargement. This non-randomized study suggested that low doses of radiation may be an alternative treatment for ARMD without an immediate drop in visual acuity or significant radiation morbidity. (author)

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.

20 CFR 404.1584 - Evaluation of work activity of blind people.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Evaluation of work activity of blind people... Evaluation of work activity of blind people. (a) General. If you are blind (as explained in § 404.1581), we... gainful activity are the same for blind people as for others. See § 404.1574(b)(2) for the earnings...

Composite vortex ordering in superconducting films with arrays of blind holes

International Nuclear Information System (INIS)

Berdiyorov, G R; Milosevic, M V; Peeters, F M

2009-01-01

The pinning properties of a superconducting thin film with a square array of blind holes are studied using the nonlinear Ginzburg-Landau theory. Although blind holes provide a weaker pinning potential than holes (also called antidots), several novel vortex structures are predicted for different size and thickness of the blind holes. Orientational dimer and trimer vortex states as well as concentric vortex shells can nucleate in the blind holes. In addition, we predict the stabilization of giant vortices that may be located both in the pinning centers and/or at the interstitial sites, as well as the combination of giant vortices with sets of individual vortices. For large blind holes, local vortex shell structures inside the blind holes may transfer their symmetry to interstitial vortices as well. The subtle interplay of shell formation and traditional Abrikosov vortex lattices inside the blind holes is also studied for different numbers of trapped vortices.

Prevalence and causes of low vision and blindness in Baotou

Science.gov (United States)

Zhang, Guisen; Li, Yan; Teng, Xuelong; Wu, Qiang; Gong, Hui; Ren, Fengmei; Guo, Yuxia; Liu, Lei; Zhang, Han

2016-01-01

Abstract The aim of this study was to investigate the prevalence and causes of low vision and blindness in Baotou, Inner Mongolia. A cross-sectional study was carried out. Multistage sampling was used to select samples. The visual acuity was estimated using LogMAR and corrected by pinhole as best-corrected visual acuity. There were 7000 samples selected and 5770 subjects included in this investigation. The overall bilateral prevalence rates of low vision and blindness were 3.66% (95% CI: 3.17–4.14) and 0.99% (95% CI: 0.73–1.24), respectively. The prevalence of bilateral low vision, blindness, and visual impairment increased with age and decreased with education level. The main leading cause of low vision and blindness was cataract. Diabetic retinopathy and age-related macular degeneration were found to be the second leading causes of blindness in Baotou. The low vision and blindness were more prevalent in elderly people and subjects with low education level in Baotou. Cataract was the main cause for visual impairment and more attention should be paid to fundus diseases. In order to prevent blindness, much more eye care programs should be established. PMID:27631267

Constrained blind deconvolution using Wirtinger flow methods

KAUST Repository

Walk, Philipp

2017-09-04

In this work we consider one-dimensional blind deconvolution with prior knowledge of signal autocorrelations in the classical framework of polynomial factorization. In particular this univariate case highly suffers from several non-trivial ambiguities and therefore blind deconvolution is known to be ill-posed in general. However, if additional autocorrelation information is available and the corresponding polynomials are co-prime, blind deconvolution is uniquely solvable up to global phase. Using lifting, the outer product of the unknown vectors is the solution to a (convex) semi-definite program (SDP) demonstrating that -theoretically- recovery is computationally tractable. However, for practical applications efficient algorithms are required which should operate in the original signal space. To this end we also discuss a gradient descent algorithm (Wirtinger flow) for the original non-convex problem. We demonstrate numerically that such an approach has performance comparable to the semidefinite program in the noisy case. Our work is motivated by applications in blind communication scenarios and we will discuss a specific signaling scheme where information is encoded into polynomial roots.

Constrained blind deconvolution using Wirtinger flow methods

KAUST Repository

Walk, Philipp; Jung, Peter; Hassibi, Babak

2017-01-01

In this work we consider one-dimensional blind deconvolution with prior knowledge of signal autocorrelations in the classical framework of polynomial factorization. In particular this univariate case highly suffers from several non-trivial ambiguities and therefore blind deconvolution is known to be ill-posed in general. However, if additional autocorrelation information is available and the corresponding polynomials are co-prime, blind deconvolution is uniquely solvable up to global phase. Using lifting, the outer product of the unknown vectors is the solution to a (convex) semi-definite program (SDP) demonstrating that -theoretically- recovery is computationally tractable. However, for practical applications efficient algorithms are required which should operate in the original signal space. To this end we also discuss a gradient descent algorithm (Wirtinger flow) for the original non-convex problem. We demonstrate numerically that such an approach has performance comparable to the semidefinite program in the noisy case. Our work is motivated by applications in blind communication scenarios and we will discuss a specific signaling scheme where information is encoded into polynomial roots.

Change Blindness Phenomena for Virtual Reality Display Systems.

Science.gov (United States)

Steinicke, Frank; Bruder, Gerd; Hinrichs, Klaus; Willemsen, Pete

2011-09-01

In visual perception, change blindness describes the phenomenon that persons viewing a visual scene may apparently fail to detect significant changes in that scene. These phenomena have been observed in both computer-generated imagery and real-world scenes. Several studies have demonstrated that change blindness effects occur primarily during visual disruptions such as blinks or saccadic eye movements. However, until now the influence of stereoscopic vision on change blindness has not been studied thoroughly in the context of visual perception research. In this paper, we introduce change blindness techniques for stereoscopic virtual reality (VR) systems, providing the ability to substantially modify a virtual scene in a manner that is difficult for observers to perceive. We evaluate techniques for semiimmersive VR systems, i.e., a passive and active stereoscopic projection system as well as an immersive VR system, i.e., a head-mounted display, and compare the results to those of monoscopic viewing conditions. For stereoscopic viewing conditions, we found that change blindness phenomena occur with the same magnitude as in monoscopic viewing conditions. Furthermore, we have evaluated the potential of the presented techniques for allowing abrupt, and yet significant, changes of a stereoscopically displayed virtual reality environment.

Blindness following bleb-related infection in open angle glaucoma.

Science.gov (United States)

Yamada, Hiroki; Sawada, Akira; Kuwayama, Yasuaki; Yamamoto, Tetsuya

2014-11-01

To estimate the risk of blindness following bleb-related infection after trabeculectomy with mitomycin C in open angle glaucoma, utilizing data obtained from two prospective multicenter studies. The incidence of bleb-related infection in open angle glaucoma after the first or second glaucoma surgery was calculated using a Kaplan-Meier analysis and data from the Collaborative Bleb-related Infection Incidence and Treatment Study (CBIITS). The rate of blindness following bleb-related infection was calculated using data from the Japan Glaucoma Society Survey of Bleb-related Infection (JGSSBI). Finally, the rate of blindness following bleb-related infection after filtering surgery was estimated based on the above two data sets. Blindness was defined as an eye with a visual acuity of 0.04 or less. The incidences of development of bleb-related infection at 5 years were 2.6 ± 0.7 % (calculated cumulative incidence ± standard error) for all infections and 0.9 ± 0.4 % for endophthalmitis in all cases in the CBIITS data. The rates of blindness in the JGSSBI data were 14 % for the total cases with bleb-related infection and 30 % for the endophthalmitis subgroup. The rate of blindness developing within 5 years following trabeculectomy was estimated to be approximately 0.24-0.36 %. The rate of blindness following bleb-related infection within 5 years after trabeculectomy is considerable and thus careful consideration must be given to the indication for trabeculectomy and the selection of surgical techniques.

Prevalence and causes of low vision and blindness worldwide

Directory of Open Access Journals (Sweden)

A.O . Oduntan

2005-12-01

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.

Ask a Scientist: What is Color Blindness?

Medline Plus

Full Text Available ... blindness, whether it can be treated, and how people become color blind. What do my eyes do when I’m sleeping? Click to Watch What does it mean to be nearsighted or farsighted? Click to Watch Do fish have eyelids? Click to Watch Why don’t all animal eyes look the same? Click to Watch Why ...

Growth-induced strong pinning sites in laser ablated YBa2Cu3O7-δ films with a non-random distribution

International Nuclear Information System (INIS)

Huijbregtse, J.M.; Klaassen, F.C.; Geest, R.C.F. van der; Dam, B.; Griessen, R.

1999-01-01

Recently, the authors showed that natural linear defects are the origin of the high critical currents in laser ablated YGBa 2 Cu 3 O 7-δ films. Combining wet-chemical etching and Atomic Force Microscopy, they find that these dislocations are created by island coalescence during growth. Consequently, the defect density can be reproducibly varied by manipulating the density of growth islands, which in turn depends on the substrate temperature. Interestingly, the radial defect distribution function approaches zero at small distances, indicating short range order. Therefore, they are now able to study vortex matter in films with a tailored non-random distribution of natural strong pinning sites

Assessment of blinding success among dental implant clinical trials: A systematic review

Directory of Open Access Journals (Sweden)

Jafar Kolahi

2015-01-01

Full Text Available Introduction: It is widely believed that blinding is a cornerstone of randomized clinical trials and that significant bias may result from unsuccessful blinding. However, it is not enough to claim that a clinical trial is single- or double-blinded and that assessment of the success of blinding is ideal. The aim of this study was to evaluate the prevalence of assessment of blinding success among dental implant clinical trials and to introduce methods of blinding assessment to the implant research community. Methods: In November 2014, PubMed was searched by blinded and experienced researchers with the query "implant AND (blindFNx01 OR maskFNx01" using the following filters: (1 Article type: clinical trial; (2 Journal categories: dental journals; (3 Field: title/abstract. Consequently, title/abstract was reviewed in all relevant articles to find any attempt to assess the success of blinding in dental implant clinical trials. Results: The PubMed search results yielded 86 clinical trials. The point of interest is that when "blindFNx01 OR maskFNx01" was deleted from the query, the number of results increased to 1688 clinical trials. This shows that only 5% of dental implant clinical trials tried to use blinding. Disappointingly, we could not find any dental implant clinical trial reporting any attempt to assess the success of blinding. Conclusion: The current status of turning a blind eye to unblinding in dental implant clinical trials is not tolerable and needs to be improved. Researchers, protocol reviewers, local ethical committees, journal reviewers, and editors should make a concerted effort to incorporate, report, and publish such information to understand its potential impact on study results.

Drunk, but not blind: the effects of alcohol intoxication on change blindness.

Science.gov (United States)

Colflesh, Gregory J H; Wiley, Jennifer

2013-03-01

Alcohol use has long been assumed to alter cognition via attentional processes. To better understand the cognitive consequences of intoxication, the present study tested the effects of moderate intoxication (average BAC between .071 and .082) on attentional processing using complex working memory capacity (WMC) span tasks and a change blindness task. Intoxicated and sober participants were matched on baseline WMC performance, and intoxication significantly decreased performance on the complex span tasks. Surprisingly, intoxication improved performance on the change blindness task. The results are interpreted as evidence that intoxication decreases attentional control, causing either a shift towards more passive processing and/or a more diffuse attentional state. This may result in decreased performance on tasks where attentional control or focus are required, but may actually facilitate performance in some contexts. Copyright © 2013 Elsevier Inc. All rights reserved.

Effect of visual experience on structural organization of the human brain: A voxel based morphometric study using DARTEL

Energy Technology Data Exchange (ETDEWEB)

Modi, Shilpi, E-mail: modi_shilpi@yahoo.co.in [NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (DRDO), Lucknow Road, Timarpur, Delhi (India); Bhattacharya, Manisha, E-mail: manishab10@gmail.com [NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (DRDO), Lucknow Road, Timarpur, Delhi (India); Singh, Namita, E-mail: namita23m@gmail.com [NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (DRDO), Lucknow Road, Timarpur, Delhi (India); Tripathi, Rajendra Prasad, E-mail: director@inmas.drdo.in [NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (DRDO), Lucknow Road, Timarpur, Delhi (India); Khushu, Subash, E-mail: skhushu@yahoo.com [NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (DRDO), Lucknow Road, Timarpur, Delhi (India)

2012-10-15

Objective: To investigate structural reorganization in the brain with differential visual experience using Voxel-Based Morphometry with Diffeomorphic Anatomic Registration Through Exponentiated Lie algebra algorithm (DARTEL) approach. Materials and methods: High resolution structural MR images were taken in fifteen normal sighted healthy controls, thirteen totally blind subjects and six partial blind subjects. The analysis was carried out using SPM8 software on MATLAB 7.6.0 platform. Results: VBM study revealed gray matter volume atrophy in the cerebellum and left inferior parietal cortex in total blind subjects and in left inferior parietal cortex, right caudate nucleus, and left primary visual cortex in partial blind subjects as compared to controls. White matter volume loss was found in calcarine gyrus in total blind subjects and Thlamus-somatosensory region in partially blind subjects as compared to controls. Besides, an increase in Gray Matter volume was also found in left middle occipital and middle frontal gyrus and right entorhinal cortex, and an increase in White Matter volume was found in superior frontal gyrus, left middle temporal gyrus and right Heschl's gyrus in totally blind subjects as compared to controls. Comparison between total and partial blind subjects revealed a greater Gray Matter volume in left cerebellum of partial blinds and left Brodmann area 18 of total blind subjects. Conclusion: Results suggest that, loss of vision at an early age can induce significant structural reorganization on account of the loss of visual input. These plastic changes are different in early onset of total blindness as compared to partial blindness.

Effect of visual experience on structural organization of the human brain: a voxel based morphometric study using DARTEL.

Science.gov (United States)

Modi, Shilpi; Bhattacharya, Manisha; Singh, Namita; Tripathi, Rajendra Prasad; Khushu, Subash

2012-10-01

To investigate structural reorganization in the brain with differential visual experience using Voxel-Based Morphometry with Diffeomorphic Anatomic Registration Through Exponentiated Lie algebra algorithm (DARTEL) approach. High resolution structural MR images were taken in fifteen normal sighted healthy controls, thirteen totally blind subjects and six partial blind subjects. The analysis was carried out using SPM8 software on MATLAB 7.6.0 platform. VBM study revealed gray matter volume atrophy in the cerebellum and left inferior parietal cortex in total blind subjects and in left inferior parietal cortex, right caudate nucleus, and left primary visual cortex in partial blind subjects as compared to controls. White matter volume loss was found in calcarine gyrus in total blind subjects and Thlamus-somatosensory region in partially blind subjects as compared to controls. Besides, an increase in Gray Matter volume was also found in left middle occipital and middle frontal gyrus and right entorhinal cortex, and an increase in White Matter volume was found in superior frontal gyrus, left middle temporal gyrus and right Heschl's gyrus in totally blind subjects as compared to controls. Comparison between total and partial blind subjects revealed a greater Gray Matter volume in left cerebellum of partial blinds and left Brodmann area 18 of total blind subjects. Results suggest that, loss of vision at an early age can induce significant structural reorganization on account of the loss of visual input. These plastic changes are different in early onset of total blindness as compared to partial blindness. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Effect of visual experience on structural organization of the human brain: A voxel based morphometric study using DARTEL

International Nuclear Information System (INIS)

Modi, Shilpi; Bhattacharya, Manisha; Singh, Namita; Tripathi, Rajendra Prasad; Khushu, Subash

2012-01-01

Objective: To investigate structural reorganization in the brain with differential visual experience using Voxel-Based Morphometry with Diffeomorphic Anatomic Registration Through Exponentiated Lie algebra algorithm (DARTEL) approach. Materials and methods: High resolution structural MR images were taken in fifteen normal sighted healthy controls, thirteen totally blind subjects and six partial blind subjects. The analysis was carried out using SPM8 software on MATLAB 7.6.0 platform. Results: VBM study revealed gray matter volume atrophy in the cerebellum and left inferior parietal cortex in total blind subjects and in left inferior parietal cortex, right caudate nucleus, and left primary visual cortex in partial blind subjects as compared to controls. White matter volume loss was found in calcarine gyrus in total blind subjects and Thlamus-somatosensory region in partially blind subjects as compared to controls. Besides, an increase in Gray Matter volume was also found in left middle occipital and middle frontal gyrus and right entorhinal cortex, and an increase in White Matter volume was found in superior frontal gyrus, left middle temporal gyrus and right Heschl's gyrus in totally blind subjects as compared to controls. Comparison between total and partial blind subjects revealed a greater Gray Matter volume in left cerebellum of partial blinds and left Brodmann area 18 of total blind subjects. Conclusion: Results suggest that, loss of vision at an early age can induce significant structural reorganization on account of the loss of visual input. These plastic changes are different in early onset of total blindness as compared to partial blindness

Thalamocortical Connectivity and Microstructural Changes in Congenital and Late Blindness

DEFF Research Database (Denmark)

Reislev, N H; Dyrby, Tim Bjørn; Siebner, H. R.

2017-01-01

There is ample evidence that the occipital cortex of congenitally blind individuals processes nonvisual information. It remains a debate whether the cross-modal activation of the occipital cortex is mediated through the modulation of preexisting corticocortical projections or the reorganisation...... of thalamocortical connectivity. Current knowledge on this topic largely stems from anatomical studies in animal models. The aim of this study was to test whether purported changes in thalamocortical connectivity in blindness can be revealed by tractography based on diffusion-weighted magnetic resonance imaging...... network between congenitally blind individuals, late blind individuals, and normal sighted controls, diffusion tensor imaging (DTI) indices revealed significant microstructural changes within thalamic clusters of both blind groups. Furthermore, we find a significant decrease in fractional anisotropy (FA...

Factors associated with lifetime risk of open-angle glaucoma blindness.

Science.gov (United States)

Peters, Dorothea; Bengtsson, Boel; Heijl, Anders

2014-08-01

To investigate factors associated with bilateral glaucoma blindness, particularly factors available at the time of diagnosis. Retrospective chart review of all patients with primary open-angle glaucoma (POAG) or pseudoexfoliative glaucoma (PEXG) followed at the Department of Ophthalmology or Low Vision Center of Skåne University Hospital, Malmö, Sweden, who died between January 2006 and June 2010. Disease stage at diagnosis was defined by a simplified version of Mills' glaucoma staging system using perimetric mean deviation (MD) to define six stages of severity. Blindness was defined according to WHO criteria. We used logistic regression analysis to examine the association between risk factors and glaucoma blindness. Four hundred and 23 patients were included; 60% POAG and 40% PEXG. Sixty-four patients (15%) became blind from glaucoma. Blind patients had significantly longer mean duration with diagnosed disease than patients who did not go blind (14.8 years ± 5.8 versus 10.6 years ± 6.5, p blindness increased with higher intraocular pressure (IOP) (OR 1.08, 95% CI 1.03-1.13) and with each stage of more advanced field loss at time of diagnosis (OR 1.80 95% CI 1.34-2.41). Older age at death was also associated with an increased risk of blindness (OR 1.09 95% CI 1.03-1.14), while age at diagnosis was unimportant. PEXG was not an independent risk factor for blindness. Higher IOP and worse visual field status at baseline were important risk factors, as was older age at death. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Retinopathy of prematurity as a major cause of severe visual impairment and blindness in children in schools for the blind in Guadalajara city, Mexico.

Science.gov (United States)

Zepeda-Romero, L C; Barrera-de-Leon, J C; Camacho-Choza, C; Gonzalez Bernal, C; Camarena-Garcia, E; Diaz-Alatorre, C; Gutierrez-Padilla, J A; Gilbert, C

2011-11-01

To determine the causes of blindness in students attending schools for the blind in Guadalajara city, Mexico and to assess the availability of screening for retinopathy of prematurity (ROP) in local neonatal intensive care units. Information on causes of blindness was obtained by interview with parents and teachers, review of records and examination. Causes of visual loss in children with a distance visual acuity of blind) were determined and classified according to the WHO's classification system for children. Of 153 children in the two participating schools, 144 were severely visual impaired or blind. Their ages ranged from 4 months to 15 years and 58% were female. ROP was the most common cause of visual loss (34.7%), followed by optic nerve lesions (17.4%) and glaucoma (14.6%). 25/59 (42.3%) children aged 0-4 years were blind from ROP compared with 6/32 (18.8%) children aged 10-15 years. 78% of children blind from ROP had psychomotor delay and less than half (46%) had not received treatment for ROP. All five privately funded neonatal intensive care units in the city regularly screen for ROP compared with only four of the 12 units in the public sector. ROP is the leading cause of blindness in children in Mexico despite national guidelines being in place. Health policies promoting primary prevention through improved neonatal care need to be implemented. Advocacy is required so that the time ophthalmologists spend screening and treating ROP is included in their job description and hence salaried.

The Assessment of Cognitive Development in Blind Infants and Preschoolers.

Science.gov (United States)

Brambring, M.; Troster, H.

1994-01-01

This study evaluated the Bielefeld Developmental Test for Blind Infants and Preschoolers by comparing cognitive performance of blind and sighted children (ages three and four). Results indicated that even this test (with "blind-neutral" items) did not permit a fair comparative assessment, though it did prove suitable for within-group…

Offender and offense characteristics of a nonrandom sample of adolescent mass murderers.

Science.gov (United States)

Meloy, J R; Hempel, A G; Mohandie, K; Shiva, A A; Gray, B T

2001-06-01

The authors conducted a descriptive, archival study of adolescent (murderers-subjects who intentionally killed three or more victims in one event-to identify demographic, clinical, and forensic characteristics. A nonrandom sample of convenience of adolescent mass murderers was utilized. Thirty-four subjects, acting alone or in pairs, committed 27 mass murders between 1958 and 1999. The sample consisted of males with a median age of 17. A majority were described as "loners" and abused alcohol or drugs; almost half were bullied by others, preoccupied with violent fantasy, and violent by history. Although 23% had a documented psychiatric history, only 6% were judged to have been psychotic at the time of the mass murder. Depressive symptoms and historical antisocial behaviors were predominant. There was a precipitating event in most cases--usually a perceived failure in love or school--and most subjects made threatening statements regarding the mass murder to third parties. The majority of the sample clustered into three types: the family annihilator, the classroom avenger, and the criminal opportunist. The adolescent mass murderer is often predatorily rather than affectively violent and typically does not show any sudden or highly emotional warning signs. Although the act of mass murder is virtually impossible to predict because of its extremely low frequency, certain clinical and forensic findings can alert the clinician to the need for further, intensified primary care, including family, school, community, law enforcement, and mental health intervention.

[Survey on avoidable blindness and visual impairment in Panama].

Science.gov (United States)

López, Maritza; Brea, Ileana; Yee, Rita; Yi, Rodolfo; Carles, Víctor; Broce, Alberto; Limburg, Hans; Silva, Juan Carlos

2014-12-01

Determine prevalence of blindness and visual impairment in adults aged ≥ 50 years in Panama, identify their main causes, and characterize eye health services. Cross-sectional population study using standard Rapid Assessment of Avoidable Blindness methodology. Fifty people aged ≥ 50 years were selected from each of 84 clusters chosen through representative random sampling of the entire country. Visual acuity was assessed using a Snellen chart; lens and posterior pole status were assessed by direct ophthalmoscopy. Cataract surgery coverage was calculated and its quality assessed, along with causes of visual acuity blindness was 3.0% (95% CI: 2.3-3.6). The main cause of blindness was cataract (66.4%), followed by glaucoma (10.2%). Cataract (69.2%) was the main cause of severe visual impairment and uncorrected refractive errors were the main cause of moderate visual impairment (60.7%). Surgical cataract coverage in individuals was 76.3%. Of all eyes operated for cataract, 58.0% achieved visual acuity ≤ 20/60 with available correction. Prevalence of blindness in Panama is in line with average prevalence found in other countries of the Region. This problem can be reduced, since 76.2% of cases of blindness and 85.0% of cases of severe visual impairment result from avoidable causes.

Survey of childhood blindness and visual impairment in Botswana

Science.gov (United States)

Nallasamy, Sudha; Anninger, William V; Quinn, Graham E; Kroener, Brian; Zetola, Nicola M; Nkomazana, Oathokwa

2014-01-01

Background/aims In terms of blind-person years, the worldwide burden of childhood blindness is second only to cataracts. In many developing countries, 30–72% of childhood blindness is avoidable. The authors conducted this study to determine the causes of childhood blindness and visual impairment (VI) in Botswana, a middle-income country with limited access to ophthalmic care. Methods This study was conducted over 4 weeks in eight cities and villages in Botswana. Children were recruited through a radio advertisement and local outreach programmes. Those ≤15 years of age with visual acuity Blindness Eye Examination Record for Children with Blindness and Low Vision was used to record data. Results The authors enrolled 241 children, 79 with unilateral and 162 with bilateral VI. Of unilateral cases, 89% were avoidable: 23% preventable (83% trauma-related) and 66% treatable (40% refractive error and 31% amblyopia). Of bilateral cases, 63% were avoidable: 5% preventable and 58% treatable (33% refractive error and 31% congenital cataracts). Conclusion Refractive error, which is easily correctable with glasses, is the most common cause of bilateral VI, with cataracts a close second. A nationwide intervention is currently being planned to reduce the burden of avoidable childhood VI in Botswana. PMID:21242581

Double-blind ureteral duplication: report of two cases

International Nuclear Information System (INIS)

Choi, Ja-Young; Kim, Seung Hyup; Kim, Sun Ho

2002-01-01

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.)

Concepts and Criteria for Blind Quantum Source Separation and Blind Quantum Process Tomography

Directory of Open Access Journals (Sweden)

Alain Deville

2017-07-01

Full Text Available Blind Source Separation (BSS is an active domain of Classical Information Processing, with well-identified methods and applications. The development of Quantum Information Processing has made possible the appearance of Blind Quantum Source Separation (BQSS, with a recent extension towards Blind Quantum Process Tomography (BQPT. This article investigates the use of several fundamental quantum concepts in the BQSS context and establishes properties already used without justification in that context. It mainly considers a pair of electron spins initially separately prepared in a pure state and then submitted to an undesired exchange coupling between these spins. Some consequences of the existence of the entanglement phenomenon, and of the probabilistic aspect of quantum measurements, upon BQSS solutions, are discussed. An unentanglement criterion is established for the state of an arbitrary qubit pair, expressed first with probability amplitudes and secondly with probabilities. The interest of using the concept of a random quantum state in the BQSS context is presented. It is stressed that the concept of statistical independence of the sources, widely used in classical BSS, should be used with care in BQSS, and possibly replaced by some disentanglement principle. It is shown that the coefficients of the development of any qubit pair pure state over the states of an orthonormal basis can be expressed with the probabilities of results in the measurements of well-chosen spin components.

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

Science.gov (United States)

Miles, Barbara

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

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

olfactory but reduced taste perception. In this study we tested the hypothesis that congenitally blind subjects have enhanced orthonasal but not retronasal olfactory skills. Twelve congenitally blind and 14 sighted control subjects, matched in age, gender and body mass index, were asked to identify odours...... using grocery-available food powders. Results showed that blind subjects were significantly faster and tended to be better at identifying odours presented orthonasally. This was not the case when odorants were presented retronasally. We also found a significant group x route interaction, showing...... that although both groups performed better for retronasally compared to orthonasally presented odours, this gain was less pronounced for blind subjects. Finally, our data revealed that blind subjects were more familiar with the orthonasal odorants and used the retronasal odorants less often for cooking than...

Oplysningens 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...

Acute Blindness.

Science.gov (United States)

Meekins, Jessica M

2015-09-01

Sudden loss of vision is an ophthalmic emergency with numerous possible causes. Abnormalities may occur at any point within the complex vision pathway, from retina to optic nerve to the visual center in the occipital lobe. This article reviews specific prechiasm (retina and optic nerve) and cerebral cortical diseases that lead to acute blindness. Information regarding specific etiologies, pathophysiology, diagnosis, treatment, and prognosis for vision is discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

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.

CONCEPTS OF COLORS IN CHILDREN WITH CONGENITAL BLINDNESS

Directory of Open Access Journals (Sweden)

Daniela DIMITROVA-RADOJICHIKJ

2015-11-01

Full Text Available This descriptive qualitative interview study in¬ves¬tigates knowledge of colours in students who are congenitally blind. The purpose of this research was to explore how the lack of direct experience with colour, as a result of congenital blindness, affects judgments about semantic concepts. Qualitative methods were used to conduct interviews with 15 students. The results of the study indicate that students know the colours and have a favourite colour. The implications for practice are to pay more attention when we teach students with congenital blindness to associate colours with specific objects.

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...... magnetic resonance imaging to measure changes in the blood-oxygenation level-dependent signal in congenitally blind and blindfolded sighted control subjects during a simple odor detection task. We found several group differences in task-related activations. Compared to sighted controls, congenitally blind......, linking it also to olfactory processing in addition to tactile and auditory processing....

Spatial memory and integration processes in congenital blindness.

Science.gov (United States)

Vecchi, Tomaso; Tinti, Carla; Cornoldi, Cesare

2004-12-22

The paper tests the hypothesis that difficulties met by the blind in spatial processing are due to the simultaneous treatment of independent spatial representations. Results showed that lack of vision does not impede the ability to process and transform mental images; however, blind people are significantly poorer in the recall of more than a single spatial pattern at a time than in the recall of the corresponding material integrated into a single pattern. It is concluded that the simultaneous maintenance of different spatial information is affected by congenital blindness, while cognitive processes that may involve sequential manipulation are not.

42 CFR 436.321 - Medically needy coverage of the blind.

Science.gov (United States)

2010-10-01

... 42 Public Health 4 2010-10-01 2010-10-01 false Medically needy coverage of the blind. 436.321... Optional Coverage of the Medically Needy § 436.321 Medically needy coverage of the blind. If the agency provides Medicaid to the medically needy, it may provide Medicaid to blind individuals who meet— (a) The...

Visual loss in a school for the blind in Nigeria.

Science.gov (United States)

Okoye, O I; Aghaji, A E; Ikojo, I N

2009-01-01

There are an estimated 1.4 million blind children worldwide, it has been observed that almost 90% of the so-called blind population (children inclusive) do not have total loss of visual function, but retain a degree of usable residual vision. The study aims to determined the sites and causes of visual loss in the students of a school for the blind in Nigeria, and also the proportion of those students who could benefit from low vision devices. Forty-five students of the school were examined using the standard World Health Organization/Prevention of blindness examination record for childhood blindness. Refraction and assessment for low vision devices were conducted, where necessary. Glaucoma/buphthalmos (22.2%) and corneal lesions (20%) were the major causes of vision loss. Six students (13.3%) benefited from spectacles and/or low vision devices. Glaucoma/buphthalmos is assuming great significance in this study population, though most of the causes of vision loss are avoidable (77.7%). There is need for low vision service in the schools for the blind in South East Nigeria.

Food experiences and eating patterns of visually impaired and blind people.

Science.gov (United States)

Bilyk, Marie Claire; Sontrop, Jessica M; Chapman, Gwen E; Barr, Susan I; Mamer, Linda

2009-01-01

The number of visually impaired and blind Canadians will rise dramatically as our population ages, and yet little is known about the impact of blindness on the experience of food and eating. In this qualitative study, the food experiences and eating patterns of visually impaired and blind people were examined. Influencing factors were also explored. In 2000, nine blind or severely visually impaired subjects were recruited through blindness-related organizations in British Columbia. Participants completed individual semi-structured, in-depth interviews. These were transcribed verbatim, coded, and analyzed to explicate participants' experiences. Participants experienced blindness-related obstacles when shopping for food, preparing food, and eating in restaurants. Inaccessible materials and environments left participants with a diet lacking in variety and limited access to physical activity. Seven participants were overweight or obese, a finding that may be related to limited physical activity and higher-than-average restaurant use. This is the first study in which the experience of food and eating is described from the perspective of visually impaired Canadians. Nutrition and blindness professionals must work together to reduce the food-related obstacles faced by visually impaired and blind people. Professionals must address both individual skill development and social and structural inequities.

Pain perception is increased in congenital but not late onset blindness

DEFF Research Database (Denmark)

Slimani, Hocine; Danti, Sabrina; Ptito, Maurice

2014-01-01

There is now ample evidence that blind individuals outperform sighted individuals in various tasks involving the non-visual senses. In line with these results, we recently showed that visual deprivation from birth leads to an increased sensitivity to pain. As many studies have shown that congenit......There is now ample evidence that blind individuals outperform sighted individuals in various tasks involving the non-visual senses. In line with these results, we recently showed that visual deprivation from birth leads to an increased sensitivity to pain. As many studies have shown...... that congenitally and late blind individuals show differences in their degree of compensatory plasticity, we here address the question whether late blind individuals also show hypersensitivity to nociceptive stimulation. We therefore compared pain thresholds and responses to supra-threshold nociceptive stimuli...... in congenitally blind, late blind and normally sighted volunteers. Participants also filled in questionnaires measuring attention and anxiety towards pain in everyday life. Results show that late blind participants have pain thresholds and ratings of supra-threshold heat nociceptive stimuli similar...

Spontaneous facial expressions of emotion of congenitally and noncongenitally blind individuals.

Science.gov (United States)

Matsumoto, David; Willingham, Bob

2009-01-01

The study of the spontaneous expressions of blind individuals offers a unique opportunity to understand basic processes concerning the emergence and source of facial expressions of emotion. In this study, the authors compared the expressions of congenitally and noncongenitally blind athletes in the 2004 Paralympic Games with each other and with those produced by sighted athletes in the 2004 Olympic Games. The authors also examined how expressions change from 1 context to another. There were no differences between congenitally blind, noncongenitally blind, and sighted athletes, either on the level of individual facial actions or in facial emotion configurations. Blind athletes did produce more overall facial activity, but these were isolated to head and eye movements. The blind athletes' expressions differentiated whether they had won or lost a medal match at 3 different points in time, and there were no cultural differences in expression. These findings provide compelling evidence that the production of spontaneous facial expressions of emotion is not dependent on observational learning but simultaneously demonstrates a learned component to the social management of expressions, even among blind individuals.

Experts' understanding of partial derivatives using the Partial Derivative Machine

OpenAIRE

Roundy, David; Dorko, Allison; Dray, Tevian; Manogue, Corinne A.; Weber, Eric

2014-01-01

Partial derivatives are used in a variety of different ways within physics. Most notably, thermodynamics uses partial derivatives in ways that students often find confusing. As part of a collaboration with mathematics faculty, we are at the beginning of a study of the teaching of partial derivatives, a goal of better aligning the teaching of multivariable calculus with the needs of students in STEM disciplines. As a part of this project, we have performed a pilot study of expert understanding...

Age and sex distribution of blindness in Ahoada East Local ...

African Journals Online (AJOL)

Background: Differences exist in the impact of blindness by age and sex; the overall risk of death being higher for blind males than females. Aim: To describe the age and sex differences among the blind in Ahoada-East Local Government Area (LGA) of Rivers State, Nigeria. Methods: Age and sex data were analyzed for 24 ...

42 CFR 435.133 - Blind and disabled individuals eligible in December 1973.

Science.gov (United States)

2010-10-01

... 42 Public Health 4 2010-10-01 2010-10-01 false Blind and disabled individuals eligible in December... Mandatory Coverage of the Aged, Blind, and Disabled § 435.133 Blind and disabled individuals eligible in... December 1973 as blind or disabled individuals, whether or not they were receiving cash assistance in...

Information on blinding in registered records of clinical trials

Directory of Open Access Journals (Sweden)

Viergever Roderik F

2012-11-01

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

Are Students Blind to Their Ethical Blind Spots? An Exploration of Why Ethics Education Should Focus on Self-Perception Biases

Science.gov (United States)

Tomlin, Kathleen A.; Metzger, Matthew L.; Bradley-Geist, Jill; Gonzalez-Padron, Tracy

2017-01-01

Ethics blind spots, which have become a keystone of the emerging behavioral ethics literature, are essentially biases, heuristics, and psychological traps. Though students typically recognize that ethical challenges exist in the world at large, they often fail to see when they are personally prone to ethics blind spots. This creates an obstacle…

Blind spot detection & passive lane change assist systems

NARCIS (Netherlands)

Surovtcev, I.

2015-01-01

The project goal was design and implementation of proof-of-concept for two systems that aim to tackle the blind spot problem of for the commercial vehicles: Blind Spot Detection and Passive Lane Change Assist functions. The system implementation was done using Rapid Control Prototype (RCP) hardware.

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.

Index finger somatosensory evoked potentials in blind Braille readers.

Science.gov (United States)

Giriyappa, Dayananda; Subrahmanyam, Roopakala Mysore; Rangashetty, Srinivasa; Sharma, Rajeev

2009-01-01

Traditionally, vision has been considered the dominant modality in our multi-sensory perception of the surrounding world. Sensory input via non-visual tracts becomes of greater behavioural relevance in totally blind individuals to enable effective interaction with the world around them. These include audition and tactile perceptions, leading to an augmentation in these perceptions when compared with normal sighted individuals. The objective of the present work was to study the index finger somatosensory evoked potentials (SEPs) in totally blind and normal sighted individuals. SEPs were recorded in 15 Braille reading totally blind females and compared with 15 age-matched normal sighted females. Latency and amplitudes of somatosensory evoked potential waveforms (N9, N13, and N20) were measured. Amplitude of N20 SEP (a cortical somatosensory evoked potential) was significantly larger in the totally blind than in normal sighted individuals (p Braille reading right index finger. Totally blind Braille readers have larger N20 amplitude, suggestive of greater somatosensory cortical representation of the Braille reading index finger.

Blind Reduced-Rank MMSE Detector for DS-CDMA Systems

Directory of Open Access Journals (Sweden)

Xiaodong Cai

2003-01-01

Full Text Available We first develop a reduced-rank minimum mean squared error (MMSE detector for direct-sequence (DS code division multiple access (CDMA by forcing the linear MMSE detector to lie in a signal subspace of a reduced dimension. While a reduced-rank MMSE detector has lower complexity, it cannot outperform the full-rank MMSE detector. We then concentrate on the blind reduced-rank MMSE detector which is obtained from an estimated covariance matrix. Our analysis and simulation results show that when the desired user′s signal is in a low-dimensional subspace, there exists an optimal subspace so that the blind reduced-rank MMSE detector lying in this subspace has the best performance. By properly choosing a subsspace, we guarantee that the optimal blind reduced-rank MMSE detector is obtained. An adaptive blind reduced-rank MMSE detector, based on a subspace tracking algorithm, is developed. The adaptive blind reduced-rank MMSE detector exhibits superior steady-state performance and fast convergence speed.

Color blindness among multiple sclerosis patients in Isfahan.

Science.gov (United States)

Shaygannejad, Vahid; Golabchi, Khodayar; Dehghani, Alireza; Ashtari, Fereshteh; Haghighi, Sepehr; Mirzendehdel, Mahsa; Ghasemi, Majid

2012-03-01

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. 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. 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). 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.

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.

Prevalence of blindness and cataract surgical outcomes in Takeo Province, Cambodia.

Science.gov (United States)

Mörchen, Manfred; Langdon, Toby; Ormsby, Gail M; Meng, Ngy; Seiha, Do; Piseth, Kong; Keeffe, Jill E

2015-01-01

To estimate the prevalence of blindness and cataract surgical outcomes in persons 50 years or older above in Takeo Province, Cambodia. A population based survey. A total of 93 villages were selected through probability proportionate to size using the Rapid Assessment of Avoidable Blindness methodology. Households from 93 villages were selected using compact segment sampling. Visual acuity (VA) of 4650 people 50 years or older was tested and lens status and cause of visual impairment were assessed. The response rate was 96.2%. The age- and sex-adjusted prevalence of bilateral blindness [presenting visual acuity (PVA) blind in Takeo Province. The age- and sex-adjusted prevalence of low vision (PVA blind was 64.7% (female 59.5%, male 78.1%). Cataract surgical outcome was poor (best-corrected visual acuity blindness. A repeated survey using the same methodology after 8-12 years might be helpful in proving genuine change over time.

Oxcarbazepine versus carbamazepine monotherapy for partial onset seizures.

Science.gov (United States)

Koch, Marcus W; Polman, Susanne Kl

2009-10-07

Partial onset seizures are often treated with the standard antiepileptic drug carbamazepine. Oxcarbazepine is a newer antiepileptic drug related to carbamazepine that is claimed to be better tolerated. To compare efficacy and tolerability of carbamazepine and oxcarbazepine monotherapy for partial onset seizures. We searched the Cochrane Epilepsy Group Specialised Register (4 August 2009), the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library issue 3, 2009), MEDLINE (January 1966 to May 2008), reference lists of relevant articles and conference proceedings. We also contacted manufacturers and researchers in the field for published or unpublished data. Blinded and unblinded randomised controlled trials of carbamazepine versus oxcarbazepine monotherapy for partial onset seizures. Both authors independently assessed trial quality, according to the guidelines in the Cochrane Reviewer's Handbook, and extracted information about study population, type of intervention, outcome measures and study design. All analyses in this review are by intention-to-treat. We tested for statistical heterogeneity among the identified studies using the chi-squared test. Three trials (723 participants) were included. Only one trial used adequate outcome measures of efficacy; therefore, the results pertaining to efficacy are based on a single trial, whereas the results pertaining to adverse events are based on all three included trials. There was no overall difference in time to treatment withdrawal between the two drugs (hazard ratio (HR) of oxcarbazepine (OXC) versus carbamazepine (CBZ): 1.04, 95% confidence interval (CI) 0.78 to 1.39). Further analyses showed no significant difference in treatment withdrawal for unacceptable side effects (HR of OXC versus CBZ: 0.85, 95% CI 0.59 to 1.24) and in treatment withdrawal for inadequate seizure control (HR of OXC versus CBZ: 1.33, 95% CI 0.82 to 2.15). Oxcarbazepine and carbamazepine appeared to be similarly effective

Dynamic postural stability in blind athletes using the biodex stability system.

Science.gov (United States)

Aydoğ, E; Aydoğ, S T; Cakci, A; Doral, M N

2006-05-01

Three systems affect the upright standing posture in humans - visual, vestibular, and somatosensory. It is well known that the visually impaired individuals have bad postural balance. On the other hand, it is a well documented fact that some sports can improve postural balance. Therefore, it is aimed in this study to evaluate the dynamic postural stability in goal-ball athletes. Twenty blind goal-ball players, 20 sighted and 20 sedentary blind controls were evaluated using the Biodex Stability System. Three adaptation trials and three test evaluations (a 20-second balance test at a platform stability of 8) were applied to the blind people, and to the sighted with eyes open and closed. Dynamic postural stability was measured on the basis of three indices: overall, anteroposterior, and mediolateral. Means of each test score were calculated. The tests results were compared for the blind athletes, sighted (with eyes open and closed) subjects, and sedentary blind people. There were significant differences between the results of the blind people and the sighted subjects with regards to all of the three indices. Although the stability of goal-ball players was better than sedentary blinds', only ML index values were statistically different (4.47 +/- 1.24 in the goal-ball players; 6.46 +/- 3.42 in the sedentary blind, p = 0.04). Dynamic postural stability was demonstrated to be affected by vision; and it was found that blind people playing goal-ball 1 - 2 days per week have higher ML stability than the sedentary sighted people.

Blindness and Visual Impairment Profile and Rapid Assessment of Avoidable Blindness in South East Asia: Analysis of New Data. 2017 APAO Holmes Lecture.

Science.gov (United States)

Das, Taraprasad

2018-03-13

The International Agency for Prevention of Blindness (IAPB) South East Asia region (SEAR) that consists of 11 countries contains 26% of the world's population (1,761,000,000). In this region 12 million are blind and 78.5 million are visually impaired. This amounts to 30% of global blindness and 32% of global visual impairment. Rapid assessment of avoidable blindness (RAAB) survey analysis. RAAB, either a repeat or a first time survey, was completed in 8 countries in this decade (2010 onwards). These include Bangladesh, Bhutan, India, Indonesia, Maldives, Sri Lanka, Thailand, and Timor Leste. Cataract is the principal cause of blindness and severe visual impairment in all countries. Refractive error is the principal cause of moderate visual impairment in 4 countries: Bangladesh, India, Maldives, and Sri Lanka; cataract continues to be the principal cause of moderate visual impairment in 4 other countries: Bhutan, Indonesia, Thailand, and Timor Leste. Outcome of cataract surgery is suboptimal in the Maldives and Timor Leste. Rigorous focus is necessary to improve cataract surgery outcomes and correction of refractive error without neglecting the quality of care. At the same time allowances must be made for care of the emerging causes of visual impairment and blindness such as glaucoma and posterior segment disorders, particularly diabetic retinopathy. Copyright 2018 Asia-Pacific Academy of Ophthalmology.

Blindness and poverty in India: the way forward.

Science.gov (United States)

Khanna, Rohit; Raman, Usha; Rao, Gullapalli N

2007-11-01

A few recent studies have shown that poverty is an exacerbating and often determining factor in the incidence of disabling conditions, including visual impairment. Recent estimates from the World Health Organization indicate that 90 per cent of all those affected by visual impairment live in the poorest countries of the world. India is home to one-fifth of the world's visually impaired people and therefore, any strategies to combat avoidable blindness must take into account the socio-economic conditions within which people live. This paper looks at the relationship between poverty and blindness in India and suggests strategies to address blindness prevention in a comprehensive manner.

Neural correlates of virtual route recognition in congenital blindness

DEFF Research Database (Denmark)

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

2010-01-01

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

A randomized, blinded study of the impact of intercessory prayer on spiritual well-being in patients with cancer.

Science.gov (United States)

Olver, Ian N; Dutney, Andrew

2012-01-01

Cochrane reviews have analyzed multiple studies on intercessory prayer that treatment teams had added to health interventions; however, the reviewers could draw no conclusions about the efficacy of prayer because the studies showed either positive or no effects and used different endpoints and methodologies. The study intended to determine whether researchers could measure the impact of intercessory prayer on spiritual well-being. The research team conducted a randomized blinded trial of intercessory prayer added to normal cancer treatment with participants agreeing to complete quality of life (QOL) and spiritual well-being scales at baseline and 6 months later. The research team had shown previously that spiritual well-being is an important, unique domain in the assessment of QOL. Participants remained blinded to the randomization. Based on a previous study, the research team determined that the study required a sample of 1000 participants to detect small differences (P = .05, 2-tailed, 80% power). SETTING The research team performed this research at the Royal Adelaide Hospital Cancer Centre, South Australia, Australia. Participants were patients at the cancer center between June 2003 and May 2008. Of 999 participants with mixed diagnoses who completed the baseline questionnaires, 66.6% provided follow-up. The average age was 61 years, and most participants were married/de facto (living with partners), were Australians or New Zealanders living in Australia, and were Christian. Intervention The research team asked an external group offering Christian intercessory prayer to add the study's participants to their usual prayer lists. They received details about the participants, but this information was not sufficient to identify them. Outcome Measures The research team used the Functional Assessment of Chronic Illness Therapy-Spiritual Well-being questionnaire to assess spiritual wellbeing and QOL. Results The intervention group showed significantly greater

Survey of blindness and low vision in Egbedore, South-Western Nigeria.

Science.gov (United States)

Kolawole, O U; Ashaye, A O; Adeoti, C O; Mahmoud, A O

2010-01-01

Developing efficient and cost-effective eye care programmes for communities in Nigeria has been hampered by inadequate and inaccurate data on blindness and low vision. To determine the prevalence and causes of blindness and low vision among adults 50 years and older in South-Western Nigeria in order to develop viable eye care programme for the community. Twenty clusters of 60 subjects of age 50 years and older were selected by systematic random cluster sampling. Information was collected and ocular examinations were conducted on each consenting subject. Data were recorded in specially designed questionnaire and analysed using descriptive statistical methods. Out of the 1200 subjects enrolled for the study, 1183(98.6%) were interviewed and examined. Seventy five (6.3%)) of the 1183 subjects were bilaterally blind and 223(18.9%) had bilateral low vision according to WHO definition of blindness and low vision. Blindness was about 1.6 times commoner in men than women. Cataract, glaucoma and posterior segment disorders were major causes of bilateral blindness. Bilateral low vision was mainly due to cataract, refractive errors and posterior segment disorders. The prevalence of blindness and low vision in this study population was high. The main causes are avoidable. Elimination of avoidable blindness and low vision calls for attention and commitment from government and eye care workers in South Western Nigeria.

Stochastic Blind Motion Deblurring

KAUST Repository

Xiao, Lei; Gregson, James; Heide, Felix; Heidrich, Wolfgang

2015-01-01

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

the common causes of blindness in north western nigeria

African Journals Online (AJOL)

million blind people in the World and 110 million people with low vision, ... Early treatment of infections and ... Age-related macular degeneration (ARMD), diabetic maculopathy ... effective use of resources for the prevention of blindness will.

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

Altered sleep-wake patterns in blindness

DEFF Research Database (Denmark)

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

2016-01-01

discuss variability in the sleep–wake pattern between blind and normal-sighted individuals. Methods Thirty-day actigraphy recordings were collected from 11 blind individuals without residual light perception and 11 age- and sex-matched normal-sighted controls. From these recordings, we extracted...... the Pittsburgh Sleep Quality Index, and chronotype, using the Morningness-Eveningness Questionnaire. Results Although no group differences were found when averaging over the entire recording period, we found a greater variability throughout the 30-days in both sleep efficiency and timing of the night-time sleep...

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

Science.gov (United States)

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

2009-04-01

The authors propose that the content of certain sociopolitical ideologies can be shaped by individuals in ways that satisfy their social motivations. This notion was tested in the context of color-blind ideology. Color blindness, when construed as a principle of distributive justice, is an egalitarian stance concerned with reducing discrepancies between groups' outcomes; as a principle of procedural justice, however, color blindness can function as a legitimizing ideology that entrenches existing inequalities. In Study 1, White people high in antiegalitarian sentiment were found to shift their construal of color blindness from a distributive to a procedural principle when exposed to intergroup threat. In Studies 2, 3A, and 3B, the authors used manipulations and a measure of threat to show that antiegalitarian White people endorse color blindness to legitimize the racial status quo. In Study 3B, participants' endorsement of color-blind ideology was mediated by increases in their preference for equal treatment (i.e., procedural justice) as a response to threat. In the Discussion section, the authors examine implications of the present perspective for understanding the manner in which individuals compete over the meaning of crucial ideologies. (c) 2009 APA, all rights reserved.

The research progress of perforating gun inner wall blind hole machining method

Science.gov (United States)

Wang, Zhe; Shen, Hongbing

2018-04-01

Blind hole processing method has been a concerned technical problem in oil, electronics, aviation and other fields. This paper introduces different methods for blind hole machining, focus on machining method for perforating gun inner wall blind hole processing. Besides, the advantages and disadvantages of different methods are also discussed, and the development trend of blind hole processing were introduced significantly.

The Economic Impact of Blindness in Europe.

Science.gov (United States)

Chakravarthy, Usha; Biundo, Eliana; Saka, Rasit Omer; Fasser, Christina; Bourne, Rupert; Little, Julie-Anne

2017-08-01

To estimate the annual loss of productivity from blindness and moderate to severe visual impairment (MSVI) in the population aged >50 years in the European Union (EU). We estimated the cost of lost productivity using three simple models reported in the literature based on (1) minimum wage (MW), (2) gross national income (GNI), and (3) purchasing power parity-adjusted gross domestic product (GDP-PPP) losses. In the first two models, assumptions included that all individuals worked until 65 years of age, and that half of all visual impairment cases in the >50-year age group would be in those aged between 50 and 65 years. Loss of productivity was estimated to be 100% for blind individuals and 30% for those with MSVI. None of these models included direct medical costs related to visual impairment. The estimated number of blind people in the EU population aged >50 years is ~1.28 million, with a further 9.99 million living with MSVI. Based on the three models, the estimated cost of blindness is €7.81 billion, €6.29 billion and €17.29 billion and that of MSVI €18.02 billion, €24.80 billion and €39.23 billion, with their combined costs €25.83 billion, €31.09 billion and €56.52 billion, respectively. The estimates from the MW and adjusted GDP-PPP models were generally comparable, whereas the GNI model estimates were higher, probably reflecting the lack of adjustment for unemployment. The cost of blindness and MSVI in the EU is substantial. Wider use of available cost-effective treatment and prevention strategies may reduce the burden significantly.

Changing lanes in a simulator: effects of aging on the control of the vehicle and visual inspection of mirrors and blind spot.

Science.gov (United States)

Lavalliere, Martin; Laurendeau, Denis; Simoneau, Martin; Teasdale, Normand

2011-04-01

The aim of this study was to examine lane change strategies in active younger and older drivers. Visual inspection of mirrors and the blind spot and the control of the vehicle were documented in a simulator environment. Younger (n = 10, 21-31 years) and older (n = 11, 65-75 years) active drivers drove through a continuous simulated environment including urban and rural sections. The scenario included events where, to negotiate a secure lane change, the driver needed to look at 3 regions of interest (ROI): (1) the rearview mirror, (2) the left side mirror, and (3) the left blind spot. The lane change maneuvers were necessary to avoid a vehicle parked halfway in the rightmost lane that was partially or completely blocking the lane or for overtaking a slower moving vehicle. Compared with younger drivers, older drivers showed a reduced frequency of visual inspection toward the rearview mirror and the blind spot. Also, though the older drivers showed a constant frequency of visual inspection across the 2 types of driving maneuvers, the younger drivers increased their frequency of inspection when overtaking a slower vehicle. Control of the car was mostly similar for both groups. A better knowledge of the drivers' visual search strategies when changing lanes could help in identifying suboptimal strategies at-risk of causing crashes and also serves to develop retraining programs.

Type-Directed Partial Evaluation

DEFF Research Database (Denmark)

Danvy, Olivier

1998-01-01

Type-directed partial evaluation uses a normalization function to achieve partial evaluation. These lecture notes review its background, foundations, practice, and applications. Of specific interest is the modular technique of offline and online type-directed partial evaluation in Standard ML...

Type-Directed Partial Evaluation

DEFF Research Database (Denmark)

Danvy, Olivier

1998-01-01

Type-directed partial evaluation uses a normalization function to achieve partial evaluation. These lecture notes review its background, foundations, practice, and applications. Of specific interest is the modular technique of offline and online type-directed partial evaluation in Standard ML of ...

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.

Blind Quantum Computing with Weak Coherent Pulses

Science.gov (United States)

Dunjko, Vedran; Kashefi, Elham; Leverrier, Anthony

2012-05-01

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

Electrophysiological correlates of mental navigation in blind and sighted people.

Science.gov (United States)

Kober, Silvia Erika; Wood, Guilherme; Kampl, Christiane; Neuper, Christa; Ischebeck, Anja

2014-10-15

The aim of the present study was to investigate functional reorganization of the occipital cortex for a mental navigation task in blind people. Eight completely blind adults and eight sighted matched controls performed a mental navigation task, in which they mentally imagined to walk along familiar routes of their hometown during a multi-channel EEG measurement. A motor imagery task was used as control condition. Furthermore, electrophysiological activation patterns during a resting measurement with open and closed eyes were compared between blind and sighted participants. During the resting measurement with open eyes, no differences in EEG power were observed between groups, whereas sighted participants showed higher alpha (8-12Hz) activity at occipital sites compared to blind participants during an eyes-closed resting condition. During the mental navigation task, blind participants showed a stronger event-related desynchronization in the alpha band over the visual cortex compared to sighted controls indicating a stronger activation in this brain region in the blind. Furthermore, groups showed differences in functional brain connectivity between fronto-central and parietal-occipital brain networks during mental navigation indicating stronger visuo-spatial processing in sighted than in blind people during mental navigation. Differences in electrophysiological parameters between groups were specific for mental navigation since no group differences were observed during motor imagery. These results indicate that in the absence of vision the visual cortex takes over other functions such as spatial navigation. Copyright © 2014 Elsevier B.V. All rights reserved.

Blind Naso-Endotracheal Intubation

African Journals Online (AJOL)

Difficult endotracheal intubation techniques include, use of fiberoptic bronchoscope, intubating laryngeal mask airway, tracheostomy, blind nasotracheal and retrograde intubation. According to the Difficult Airway Society guidelines, intubating with the aid of a fiberoptic scope has taken its place as the standard adjuvant for.

Rubber Hands Feel Touch, but Not in Blind Individuals

Science.gov (United States)

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. PMID:22558268

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.

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.

Pattern Perception and Pictures for the Blind

Directory of Open Access Journals (Sweden)

Melissa McCarthy

2005-01-01

Full Text Available This article reviews recent research on perception of tangible pictures in sighted and blind people. Haptic picture naming accuracy is dependent upon familiarity and access to semantic memory, just as in visual recognition. Performance is high when haptic picture recognition tasks do not depend upon semantic memory. Viewpoint matters for the ease or difficulty of interpreting haptic pictures of solid objects. Top views were easiest for sighted and blind persons when geometrical solids had constant crosssections in the vertical axis. The presence or absence of viewpoint effects depends upon the nature of the solids that are represented. Congenitally blind people do not spontaneously produce perspective drawings, but recent data suggests that depictions including linear perspective can be understood after minimal experience. The results suggest that two-dimensional configurations are not necessarily problematic for touch.

Meta-analytic comparison of randomized and nonrandomized studies of breast cancer surgery.

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Edwards, Janet P; Kelly, Elizabeth J; Lin, Yongtao; Lenders, Taryn; Ghali, William A; Graham, Andrew J

2012-06-01

Randomized controlled trials (RCTs) are thought to provide the most accurate estimation of "true" treatment effect. The relative quality of effect estimates derived from nonrandomized studies (nRCTs) remains unclear, particularly in surgery, where the obstacles to performing high-quality RCTs are compounded. We performed a meta-analysis of effect estimates of RCTs comparing surgical procedures for breast cancer relative to those of corresponding nRCTs. English-language RCTs of breast cancer treatment in human patients published from 2003 to 2008 were identified in MEDLINE, EMBASE and Cochrane databases. We identified nRCTs using the National Library of Medicine's "related articles" function and reference lists. Two reviewers conducted all steps of study selection. We included studies comparing 2 surgical arms for the treatment of breast cancer. Information on treatment efficacy estimates, expressed as relative risk (RR) for outcomes of interest in both the RCTs and nRCTs was extracted. We identified 12 RCTs representing 10 topic/outcome combinations with comparable nRCTs. On visual inspection, 4 of 10 outcomes showed substantial differences in summary RR. The pooled RR estimates for RCTs versus nRCTs differed more than 2-fold in 2 of 10 outcomes and failed to demonstrate consistency of statistical differences in 3 of 10 cases. A statistically significant difference, as assessed by the z score, was not detected for any of the outcomes. Randomized controlled trials comparing surgical procedures for breast cancer may demonstrate clinically relevant differences in effect estimates in 20%-40% of cases relative to those generated by nRCTs, depending on which metric is used.

Rapid processing of haptic cues for postural control in blind subjects.

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Schieppati, Marco; Schmid, Monica; Sozzi, Stefania

2014-07-01

Vision and touch rapidly lead to postural stabilization in sighted subjects. Is touch-induced stabilization more rapid in blind than in sighted subjects, owing to cross-modal reorganization of function in the blind? We estimated the time-period elapsing from onset of availability of haptic support to onset of lateral stabilization in a group of early- and late-onset blinds. Eleven blind (age 39.4 years±11.7SD) and eleven sighted subjects (age 30.0 years±10.0SD), standing eyes closed with feet in tandem position, touched a pad with their index finger and withdrew the finger from the pad in sequence. EMG of postural muscles and displacement of centre of foot pressure were recorded. The task was repeated fifty times, to allow statistical evaluation of the latency of EMG and sway changes following the haptic shift. Steady-state sway (with or without contact with pad, no haptic shift) did not differ between blind and sighted. On adding the haptic stimulus, EMG and sway diminished in both groups, but at an earlier latency (by about 0.5 s) in the blinds (p blinds. When the haptic stimulus was withdrawn, both groups increased EMG and sway at equally short delays. Blinds are rapid in implementing adaptive postural modifications when granted an external haptic reference. Fast processing of the stabilizing haptic spatial-orientation cues may be favoured by cortical plasticity in blinds. These findings add new information to the field of sensory-guided dynamic control of equilibrium in man. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Sleep structure in blindness is influenced by circadian desynchrony

DEFF Research Database (Denmark)

Aubin, Sébrina; Jennum, Poul; Nielsen, Tore

2018-01-01

We examined the structure, duration and quality of sleep, including non-rapid eye movement sleep and rapid eye movement sleep, in 11 blind individuals without conscious light perception and 11 age- and sex-matched sighted controls. Because blindness is associated with a greater incidence of free......-running circadian rhythms, we controlled for circadian phase by a measure of melatonin onset timing. When circadian rhythm was entrained and melatonin onset occurred at normal times, sleep structure did not differ between blind and sighted individuals. On the other hand, an abnormal timing of the circadian phase......, including delayed, shifted and unclassifiable melatonin onsets, led to larger rapid eye movement sleep latencies and increased wake times. No differences were observed for stages of non-rapid eye movement sleep, either between congenital and late blind and sighted individuals, or across the different...

Ocular morbidity patterns among children in schools for the blind in Chennai.

Science.gov (United States)

Prakash, M Vs; Sivakumar, S; Dayal, Ashutosh; Chitra, A; Subramaniam, Sudharshini

2017-08-01

To identify the morbidity patterns causing blindness in children attending schools for the blind in Chennai and comparing our data with similar studies done previously. A cross-sectional prevalence study was carried out in two schools for the blind in Chennai. Blind schools were visited by a team of ophthalmologists and optometrists. Students with best-corrected visual acuity (BCVA) worse than 3/60 in the better eye were included and relevant history was noted. Every student underwent anterior segment evaluation and detailed fundus examination. Morbidity of the better eye was taken as cause of blindness. Health records maintained by the school were referred to wherever available. The anatomical causes of blindness include optic nerve disorders in 75 (24.8%) cases, retinal disorders in 55 (18.2%), corneal disorders in 47 (15.6%), lens-related disorders in 39 (12.9%), congenital anomalies in 11 (3.6%), and congenital glaucoma in 20 (6.6%) cases. The whole globe was involved in six cases (1.99%). Among conditions causing blindness, optic atrophy seen in 73 (24.17%) cases was the most common, followed by retinal dystrophy in 44 (14.56%), corneal scarring in 35 (11.59%), cataract in 22 (7.28%), and congenital glaucoma in 20 (6.6%) cases. It was found that avoidable causes of blindness were seen in 31% of cases and incurable causes in 45%. Optic nerve atrophy and retinal dystrophy are the emerging causes of blindness, underlining the need for genetic counseling and low vision rehabilitation centers, along with a targeted approach for avoidable causes of blindness.

Multi-server blind quantum computation over collective-noise channels

Science.gov (United States)

Xiao, Min; Liu, Lin; Song, Xiuli

2018-03-01

Blind quantum computation (BQC) enables ordinary clients to securely outsource their computation task to costly quantum servers. Besides two essential properties, namely correctness and blindness, practical BQC protocols also should make clients as classical as possible and tolerate faults from nonideal quantum channel. In this paper, using logical Bell states as quantum resource, we propose multi-server BQC protocols over collective-dephasing noise channel and collective-rotation noise channel, respectively. The proposed protocols permit completely or almost classical client, meet the correctness and blindness requirements of BQC protocol, and are typically practical BQC protocols.

Automatic postural response systems in individuals with congenital total blindness.

Science.gov (United States)

Nakata, H; Yabe, K

2001-07-01

This study examined the effects of the absence of vision from birth on automatic postural responses to platform displacements during stance. Postural responses were induced by producing randomly four types of perturbations which consisted of forward and backward translations, and toe up and down rotations. Nine congenitally totally blind and nine sighted adults served as subjects. EMG signals were recorded from four muscles in the right leg, and reaction time to somatosensory stimuli generated by platform displacements was measured by pushing a hand-held button. To assess the ability to control postural balance, the root mean square (RMS) values for lateral and antero-posterior sway before, during, and after perturbations were calculated. The EMG amplitude in the gastrocnemius muscle of a blind subject was smaller than that of a sighted subject with eyes closed. No significant differences were found between blind and sighted subjects in EMG latencies of the lower extremity muscles in response to perturbations. The blind subjects had significantly faster reaction times to somatosensory stimuli triggered by platform displacements, but in toe down rotations no significant difference was found between blind and sighted subjects. The difference in the EMG latencies and reaction times between the two groups suggests that blindness from birth may not affect the spinal stretch reflex, but may affect a volitional act mediated through the motor cortex. There were also no significant differences in the RMS values for postural sway between blind and sighted subjects with eyes open or closed, although blind subjects swayed more after backward translations than did sighted subjects with eyes open. Results suggest that the ability to control postural balance during perturbations was not affected by vision loss from birth. Our findings suggest that the automatic postural response systems of humans are unaffected by the absence of vision from birth and are rather hard wired.

A STUDY ON PREVALENCE AND CAUSES OF CORNEAL BLINDNESS IN PAEDIATRIC AGE GROUP

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E. Ramadevi

2017-12-01

Full Text Available BACKGROUND Corneal disease is responsible for less than 2% of blindness in children in industrialised countries. In poor countries of the world, corneal scarring occurs due to vitamin A deficiency, measles and ophthalmia neonatorum. Thus, corneal disease is an important cause of blindness among children living in developing nations, which already carry a major burden of blindness. The aim of the study is to study the1. Prevalence of corneal blindness in the paediatric age group. 2. Causes of corneal blindness in the paediatric age group. 3. Morbidity of corneal blindness in the paediatric age group. MATERIALS AND METHODS It was cross-sectional observational study. Study Period- December 2014 to August 2016. Study Done- Government General Hospital, Kakinada. Sample Size- 50 patients. Inclusion Criteria- Children of age group 6 to 12 years with corneal blindness who have attended the outpatient department during the study period. Exclusion Criteria- Children with childhood blindness other than corneal pathology. Study Tools- Predesigned, semi-structured questionnaire regarding age, sex and age of onset of visual loss, laterality, history of ocular injury, vitamin A immunisation, family history of consanguinity and place of residence and socioeconomic status was taken. Visual acuity was measured using an E optotype and Landolt broken C chart with best corrected vision. Visual loss was classified according to the WHO categories of visual impairment. Ophthalmic examination was done by slit lamp and B scan. RESULTS Ocular trauma and corneal ulcers are most common cause of corneal blindness. 84% of corneal blindness cases were preventable and curable. CONCLUSION Trauma was the commonest cause of corneal blindness followed by infectious keratitis. 84% of corneal blindness was preventable and curable. Most causes of corneal blindness were avoidable.

20 CFR 416.1331 - Termination of your disability or blindness payments.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Termination of your disability or blindness... your disability or blindness payments. (a) General. The last month for which we can pay you benefits based on disability or blindness is the second month after the month in which your disability or...

77 FR 42187 - Relay Services for Deaf-Blind Individuals

Science.gov (United States)

2012-07-18

... for Deaf-Blind Individuals AGENCY: Federal Communications Commission. ACTION: Final rule; announcement... the Commission's Implementation of the Twenty-First Century Communications and Video Accessibility Act of 2010, Section 105, Relay Services for Deaf-Blind Individuals, Order (Order). This document is...

Compatriot partiality and cosmopolitan justice: Can we justify compatriot partiality within the cosmopolitan framework?

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Rachelle Bascara

2016-10-01

Full Text Available This paper shows an alternative way in which compatriot partiality could be justified within the framework of global distributive justice. Philosophers who argue that compatriot partiality is similar to racial partiality capture something correct about compatriot partiality. However, the analogy should not lead us to comprehensively reject compatriot partiality. We can justify compatriot partiality on the same grounds that liberation movements and affirmative action have been justified. Hence, given cosmopolitan demands of justice, special consideration for the economic well-being of your nation as a whole is justified if and only if the country it identifies is an oppressed developing nation in an unjust global order.This justification is incomplete. We also need to say why Person A, qua national of Country A, is justified in helping her compatriots in Country A over similarly or slightly more oppressed non-compatriots in Country B. I argue that Person A’s partiality towards her compatriots admits further vindication because it is part of an oppressed group’s project of self-emancipation, which is preferable to paternalistic emancipation.Finally, I identify three benefits in my justification for compatriot partiality. First, I do not offer a blanket justification for all forms of compatriot partiality. Partiality between members of oppressed groups is only a temporary effective measure designed to level an unlevel playing field. Second, because history attests that sovereign republics could arise as a collective response to colonial oppression, justifying compatriot partiality on the grounds that I have identified is conducive to the development of sovereignty and even democracy in poor countries, thereby avoiding problems of infringement that many humanitarian poverty alleviation efforts encounter. Finally, my justification for compatriot partiality complies with the implicit cosmopolitan commitment to the realizability of global justice

Crossmodal Recruitment of the Ventral Visual Stream in Congenital Blindness

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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.

Long-Term Trends in Glaucoma-Related Blindness in Olmsted County, Minnesota

Science.gov (United States)

Malihi, Mehrdad; Moura Filho, Edney R.; Hodge, David O.; Sit, Arthur J.

2013-01-01

Objective To determine the longitudinal trends in the probability of blindness due to open-angle glaucoma (OAG) in Olmsted County, Minnesota from 1965 to 2009. Design Retrospective, population-based cohort study. Participants All residents of Olmsted County, Minnesota (40 years of age and over) who were diagnosed with OAG between January 1, 1965 to December 31, 2000. Methods All available medical records of every incident case of OAG were reviewed until December 31, 2009 to identify progression to blindness, defined as visual acuity of 20/200 or worse, and/or visual field constriction to 20° or less. Kaplan–Meier analysis was used to estimate the cumulative probability of glaucoma-related blindness. Population incidence of blindness within 10 years of diagnosis was calculated using United States Census data. Rates for subjects diagnosed in the period 1965–1980 were compared with rates for subjects diagnosed in the period 1981–2000 using logrank tests and Poisson regression models. Main Outcome Measures Cumulative probability of OAG-related blindness, and population incidence of blindness within 10 years of diagnosis. Results Probability of glaucoma-related blindness in at least one eye at 20 years decreased from 25.8 % (95% Confidence interval [CI]: 18.5–32.5) for subjects diagnosed in 1965–1980, to 13.5% (95% CI: 8.8–17.9) for subjects diagnosed in 1981–2000 (P=0.01). The population incidence of blindness within 10 years of the diagnosis decreased from 8.7 per 100,000 (95% CI: 5.9–11.5) for subjects diagnosed in 1965–1980, to 5.5 per 100,000 (95% CI: 3.9–7.2) for subjects diagnosed in 1981–2000 (P=0.02). Higher age at diagnosis was associated with increased risk of progression to blindness (Pblindness due to OAG in at least one eye have decreased over a 45 year period from 1965 to 2009. However, a significant proportion of patients still progress to blindness despite recent diagnostic and therapeutic advancements. PMID:24823760

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…

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.

Congenital blindness limits allocentric to egocentric switching ability.

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Ruggiero, Gennaro; Ruotolo, Francesco; Iachini, Tina

2018-03-01

Many everyday spatial activities require the cooperation or switching between egocentric (subject-to-object) and allocentric (object-to-object) spatial representations. The literature on blind people has reported that the lack of vision (congenital blindness) may limit the capacity to represent allocentric spatial information. However, research has mainly focused on the selective involvement of egocentric or allocentric representations, not the switching between them. Here we investigated the effect of visual deprivation on the ability to switch between spatial frames of reference. To this aim, congenitally blind (long-term visual deprivation), blindfolded sighted (temporary visual deprivation) and sighted (full visual availability) participants were compared on the Ego-Allo switching task. This task assessed the capacity to verbally judge the relative distances between memorized stimuli in switching (from egocentric-to-allocentric: Ego-Allo; from allocentric-to-egocentric: Allo-Ego) and non-switching (only-egocentric: Ego-Ego; only-allocentric: Allo-Allo) conditions. Results showed a difficulty in congenitally blind participants when switching from allocentric to egocentric representations, not when the first anchor point was egocentric. In line with previous results, a deficit in processing allocentric representations in non-switching conditions also emerged. These findings suggest that the allocentric deficit in congenital blindness may determine a difficulty in simultaneously maintaining and combining different spatial representations. This deficit alters the capacity to switch between reference frames specifically when the first anchor point is external and not body-centered.

A Charrelation Matrix-Based Blind Adaptive Detector for DS-CDMA Systems

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Zhongqiang Luo

2015-08-01

Full Text Available In this paper, a blind adaptive detector is proposed for blind separation of user signals and blind estimation of spreading sequences in DS-CDMA systems. The blind separation scheme exploits a charrelation matrix for simple computation and effective extraction of information from observation signal samples. The system model of DS-CDMA signals is modeled as a blind separation framework. The unknown user information and spreading sequence of DS-CDMA systems can be estimated only from the sampled observation signals. Theoretical analysis and simulation results show that the improved performance of the proposed algorithm in comparison with the existing conventional algorithms used in DS-CDMA systems. Especially, the proposed scheme is suitable for when the number of observation samples is less and the signal to noise ratio (SNR is low.

A Charrelation Matrix-Based Blind Adaptive Detector for DS-CDMA Systems.

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Luo, Zhongqiang; Zhu, Lidong

2015-08-14

In this paper, a blind adaptive detector is proposed for blind separation of user signals and blind estimation of spreading sequences in DS-CDMA systems. The blind separation scheme exploits a charrelation matrix for simple computation and effective extraction of information from observation signal samples. The system model of DS-CDMA signals is modeled as a blind separation framework. The unknown user information and spreading sequence of DS-CDMA systems can be estimated only from the sampled observation signals. Theoretical analysis and simulation results show that the improved performance of the proposed algorithm in comparison with the existing conventional algorithms used in DS-CDMA systems. Especially, the proposed scheme is suitable for when the number of observation samples is less and the signal to noise ratio (SNR) is low.

Blind Quantum Computation

DEFF Research Database (Denmark)

Salvail, Louis; Arrighi, Pablo

2006-01-01

We investigate the possibility of "having someone carry out the work of executing a function for you, but without letting him learn anything about your input". Say Alice wants Bob to compute some known function f upon her input x, but wants to prevent Bob from learning anything about x. The situa......We investigate the possibility of "having someone carry out the work of executing a function for you, but without letting him learn anything about your input". Say Alice wants Bob to compute some known function f upon her input x, but wants to prevent Bob from learning anything about x....... The situation arises for instance if client Alice has limited computational resources in comparison with mistrusted server Bob, or if x is an inherently mobile piece of data. Could there be a protocol whereby Bob is forced to compute f(x) "blindly", i.e. without observing x? We provide such a blind computation...... protocol for the class of functions which admit an efficient procedure to generate random input-output pairs, e.g. factorization. The cheat-sensitive security achieved relies only upon quantum theory being true. The security analysis carried out assumes the eavesdropper performs individual attacks....

Essays on partial retirement

NARCIS (Netherlands)

Kantarci, T.

2012-01-01

The five essays in this dissertation address a range of topics in the micro-economic literature on partial retirement. The focus is on the labor market behavior of older age groups. The essays examine the economic and non-economic determinants of partial retirement behavior, the effect of partial

Designing for an inclusive school of informatics for blind students

DEFF Research Database (Denmark)

Vargas Brenes, Ronald

enrolled in UNA attended education careers programmes or philosophy. So I asked myself: Why are blind people not interested in studying informatics? Then I learned about a blind student who was interested in enrolling in the system engineering career programme a few years ago, but she quit from her...... and efficient in ensuring equal opportunities for blind and sighted students, particularly in connection with system engineering or other computer science-related career programmes....

A new adaptive blind channel identification algorithm

International Nuclear Information System (INIS)

Peng Dezhong; Xiang Yong; Yi Zhang

2009-01-01

This paper addresses the blind identification of single-input multiple-output (SIMO) finite-impulse-response (FIR) systems. We first propose a new adaptive algorithm for the blind identification of SIMO FIR systems. Then, its convergence property is analyzed systematically. It is shown that under some mild conditions, the proposed algorithm is guaranteed to converge in the mean to the true channel impulse responses in both noisy and noiseless cases. Simulations are carried out to demonstrate the theoretical results.

IFLA Section of Libraries for the Blind. Expert Meeting, 1984. Papers.

Science.gov (United States)

International Federation of Library Associations, The Hague (Netherlands).

Papers on library services and developments in reading materials for the blind, which were presented at the 1984 Expert Meeting of the IFLA Section of Libraries for the Blind include: (1) "Teaching Map Concepts to the Blind" (R. B. Horsfall and B. Cox, Canada); (2) "Optical Character Recognition 'Reading' for Computerized Braille Production"…

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...

Prevalence and causes of blindness at a tertiary hospital in Douala, Cameroon

Science.gov (United States)

Eballé, André Omgbwa; Mvogo, Côme Ebana; Koki, Godefroy; Mounè, Nyouma; Teutu, Cyrille; Ellong, Augustin; Bella, Assumpta Lucienne

2011-01-01

Purpose The aim of this study was to determine the prevalence and causes of bilateral and unilateral blindness in the town of Douala and its environs based on data from the ophthalmic unit of a tertiary hospital in Douala. Methods We conducted a retrospective epidemiological survey of consultations at the eye unit of the Douala General Hospital over the last 20 years (from January 1, 1990 to December 31, 2009). Results Out of the 1927 cases of blindness, 1000 were unilateral, corresponding to a hospital prevalence of 1.84% and 927 cases were bilateral, corresponding to a hospital prevalence of 1.71%. No statistically significant difference was noted between the two (P = 0.14). The leading causes of bilateral blindness were cataract (50.1%), glaucoma (19.7%), and diabetic retinopathy (7.8%) while the leading causes of unilateral blindness were cataract (40.4%), glaucoma (14.1%), and retinal detachment (9.1%). Cataract (51.2%), cortical blindness (16.3%), and congenital glaucoma (10%) were the leading causes of bilateral blindness in children aged less than 10 years. Conclusion Blindness remains a public health problem in the Douala region with a hospital prevalence which is relatively higher than the national estimate given by the National Blindness Control Program. PMID:21966211

The Cost of Blindness in the Republic of Ireland 2010–2020

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D. Green

2016-01-01

Full Text Available Aims. To estimate the prevalence of blindness in the Republic of Ireland and the associated financial and total economic cost between 2010 and 2020. Methods. Estimates for the prevalence of blindness in the Republic of Ireland were based on blindness registration data from the National Council for the Blind of Ireland. Estimates for the financial and total economic cost of blindness were based on the sum of direct and indirect healthcare and nonhealthcare costs. Results. We estimate that there were 12,995 blind individuals in Ireland in 2010 and in 2020 there will be 17,997. We estimate that the financial and total economic costs of blindness in the Republic of Ireland in 2010 were €276.6 million and €809 million, respectively, and will increase in 2020 to €367 million and €1.1 billion, respectively. Conclusions. Here, ninety-eight percent of the cost of blindness is borne by the Departments of Social Protection and Finance and not by the Department of Health as might initially be expected. Cost of illness studies should play a role in public policy making as they help to quantify the indirect or “hidden” costs of disability and so help to reveal the true cost of illness.

The Impact of Early Visual Deprivation on Spatial Hearing: A Comparison between Totally and Partially Visually Deprived Children

Science.gov (United States)

Cappagli, Giulia; Finocchietti, Sara; Cocchi, Elena; Gori, Monica

2017-01-01

The specific role of early visual deprivation on spatial hearing is still unclear, mainly due to the difficulty of comparing similar spatial skills at different ages and to the difficulty in recruiting young blind children from birth. In this study, the effects of early visual deprivation on the development of auditory spatial localization have been assessed in a group of seven 3–5 years old children with congenital blindness (n = 2; light perception or no perception of light) or low vision (n = 5; visual acuity range 1.1–1.7 LogMAR), with the main aim to understand if visual experience is fundamental to the development of specific spatial skills. Our study led to three main findings: firstly, totally blind children performed overall more poorly compared sighted and low vision children in all the spatial tasks performed; secondly, low vision children performed equally or better than sighted children in the same auditory spatial tasks; thirdly, higher residual levels of visual acuity are positively correlated with better spatial performance in the dynamic condition of the auditory localization task indicating that the more residual vision the better spatial performance. These results suggest that early visual experience has an important role in the development of spatial cognition, even when the visual input during the critical period of visual calibration is partially degraded like in the case of low vision children. Overall these results shed light on the importance of early assessment of spatial impairments in visually impaired children and early intervention to prevent the risk of isolation and social exclusion. PMID:28443040

Probability calculus of fractional order and fractional Taylor's series application to Fokker-Planck equation and information of non-random functions

International Nuclear Information System (INIS)

Jumarie, Guy

2009-01-01

A probability distribution of fractional (or fractal) order is defined by the measure μ{dx} = p(x)(dx) α , 0 α (D x α h α )f(x) provided by the modified Riemann Liouville definition, one can expand a probability calculus parallel to the standard one. A Fourier's transform of fractional order using the Mittag-Leffler function is introduced, together with its inversion formula; and it provides a suitable generalization of the characteristic function of fractal random variables. It appears that the state moments of fractional order are more especially relevant. The main properties of this fractional probability calculus are outlined, it is shown that it provides a sound approach to Fokker-Planck equation which are fractional in both space and time, and it provides new results in the information theory of non-random functions.

The incidence of color blindness among some school children of Pokhara, Western Nepal.

Science.gov (United States)

Niroula, D R; Saha, C G

2010-03-01

The incidence of color blindness varies from race to race and different in different geographical area. Since, there is no such report about the prevalence of color blindness in the western part of Nepal, the present study had been conducted to find out the incidence of color blindness among school children of Pokhara city, western Nepal. Participant's (n=964, 474 boys, 490 girls, age group 10 to 19 years) color vision was tested by using Ishihara chart (38 plates). Among 474 boys, 18 boys were color blind with the prevalence of 3.8%. None of girls were found to be color blind. Out of 18 color blind boys, nine, six and three boys were the victims of deuteranopia, deuteranomaly and protanomaly respectively. The incidence of color blindness were more amongst the Darji (14.3%) and Newar (9.1%) ethnic groups.

The Burden of Blindness According To Age and Sex In Some ...

African Journals Online (AJOL)

Background: There are differences in the impact of blindness by age and sex; blind males having a higher risk for death than females. The aim of this study was to describe the age and sex difference among the blind in some Niger Delta communities of Nigeria. Methods: A community based, cross-sectional study was done ...

77 FR 20553 - Relay Services for Deaf-Blind Individuals

Science.gov (United States)

2012-04-05

... for Deaf-Blind Individuals AGENCY: Federal Communications Commission. ACTION: Final rule; waiver of requirement. SUMMARY: In this document, the Commission conditionally waives the requirement for National Deaf... participants to fully meet the needs of eligible low- income, deaf-blind individuals in a timely manner. DATES...

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

Triple-server blind quantum computation using entanglement swapping

Science.gov (United States)

Li, Qin; Chan, Wai Hong; Wu, Chunhui; Wen, Zhonghua

2014-04-01

Blind quantum computation allows a client who does not have enough quantum resources or technologies to achieve quantum computation on a remote quantum server such that the client's input, output, and algorithm remain unknown to the server. Up to now, single- and double-server blind quantum computation have been considered. In this work, we propose a triple-server blind computation protocol where the client can delegate quantum computation to three quantum servers by the use of entanglement swapping. Furthermore, the three quantum servers can communicate with each other and the client is almost classical since one does not require any quantum computational power, quantum memory, and the ability to prepare any quantum states and only needs to be capable of getting access to quantum channels.

A Secured Application for Generating Acoustic Signal for Blind People

OpenAIRE

PrachiPhursutkar; Apurva Bajaj; Priyanka Veer; Tai Chormale; Prof.G.M.Bhandari

2014-01-01

Visionless people face many difficulties in their daily activities. This paper is basically designed to facilitate blind people for autonomous navigation. It is based on ‘image to sound’ conversion. The mobile camera is used to captures the image in front of the blind user. This image is then equated with the database and the processed information is fetched by blind user through a set of earphones. Color information of the object is also measured and it is informed...

Blind phase retrieval for aberrated linear shift-invariant imaging systems

International Nuclear Information System (INIS)

Yu, Rotha P; Paganin, David M

2010-01-01

We develop a means to reconstruct an input complex coherent scalar wavefield, given a through focal series (TFS) of three intensity images output from a two-dimensional (2D) linear shift-invariant optical imaging system with unknown aberrations. This blind phase retrieval technique unites two methods, namely (i) TFS phase retrieval and (ii) iterative blind deconvolution. The efficacy of our blind phase retrieval procedure has been demonstrated using simulated data, for a variety of Poisson noise levels.

Memory impairment is not sufficient for choice blindness to occur

OpenAIRE

Sagana, Anna; Sauerland, Melanie; Merckelbach, Harald

2014-01-01

Choice blindness refers to the phenomenon that people can be easily misled about the choices they made in the recent past. The aim of this study was to explore the cognitive mechanisms underlying choice blindness. Specifically, we tested whether memory impairment may account for choice blindness. A total of N = 88 participants provided sympathy ratings on 10-point scales for 20 female faces. Subsequently, participants motivated some of their ratings. However, on three trials, they were presen...

Potential use of the non-random distribution of N2 and N2O mole masses in the atmosphere as a tool for tracing atmospheric mixing and isotope fractionation processes

International Nuclear Information System (INIS)

Well, R.; Langel, R.; Reineking, A.

2002-01-01

The variation in the natural abundance of 15 N in atmospheric gas species is often used to determine the mixing of trace gases from different sources. With conventional budget calculations one unknown quantity can be determined if the remaining quantities are known. From 15 N tracer studies in soils with highly enriched 15 N-nitrate a procedure is known to calculate the mixing of atmospheric and soil derived N 2 based on the measurement of the 30/28 and 29/28 ratios in gas samples collected from soil covers. Because of the non-random distribution of the mole masses 30 N 2 , 29 N 2 and 28 N 2 in the mixing gas it is possible to calculate two quantities simultaneously, i.e. the mixing ratio of atmospheric and soil derived N 2 , and the isotopic signature of the soil derived N 2 . Routine standard measurements of laboratory air had suggested a non-random distribution of N 2 -mole masses. The objective of this study was to investigate and explain the existence of non-random distributions of 15 N 15 N, 14 N 15 N and 14 N 14 N in N 2 and N 2 O in environmental samples. The calculation of theoretical isotope data resulting from hypothetical mixing of two sources differing in 15 N natural abundance demonstrated, that the deviation from an ideal random distribution of mole masses is not detectable with the current precision of mass spectrometry. 15 N-analysis of N 2 or N 2 O was conducted with randomised and non-randomised replicate samples of different origin. 15 N abundance as calculated from 29/28 ratios were generally higher in randomised samples. The differences between the treatments ranged between 0.05 and 0.17 δper mille 15 N. It was concluded that the observed randomisation effect is probably caused by 15 N 15 N fractionation during environmental processes. (author)

Interactions of cognitive and auditory abilities in congenitally blind individuals.

Science.gov (United States)

Rokem, Ariel; Ahissar, Merav

2009-02-01

Congenitally blind individuals have been found to show superior performance in perceptual and memory tasks. In the present study, we asked whether superior stimulus encoding could account for performance in memory tasks. We characterized the performance of a group of congenitally blind individuals on a series of auditory, memory and executive cognitive tasks and compared their performance to that of sighted controls matched for age, education and musical training. As expected, we found superior verbal spans among congenitally blind individuals. Moreover, we found superior speech perception, measured by resilience to noise, and superior auditory frequency discrimination. However, when memory span was measured under conditions of equivalent speech perception, by adjusting the signal to noise ratio for each individual to the same level of perceptual difficulty (80% correct), the advantage in memory span was completely eliminated. Moreover, blind individuals did not possess any advantage in cognitive executive functions, such as manipulation of items in memory and math abilities. We propose that the short-term memory advantage of blind individuals results from better stimulus encoding, rather than from superiority at subsequent processing stages.

Memory impairment is not sufficient for choice blindness to occur

Directory of Open Access Journals (Sweden)

Anna eSagana

2014-05-01

Full Text Available Choice blindness refers to the phenomenon that people can be easily misled about the choices they made in the recent past. The aim of this study was to explore the cognitive mechanisms underlying choice blindness. Specifically, we tested whether memory impairment may account for choice blindness. A total of N = 88 participants provided sympathy ratings on 10-point scales for 20 female faces. Subsequently, participants motivated some of their ratings. However, on three trials, they were presented with sympathy ratings that deviated from their original ratings by three full scale points. On nearly 41% of the trials, participants failed to detect (i.e., were blind the manipulation. After a short interval, participants were informed that some trials had been manipulated and were asked to recall their original ratings. Participants adopted the manipulated outcome in only 3% of the trials. Furthermore, the extent to which the original ratings were accurately remembered was not higher for detected as compared with non-detected trials. From a theoretical point of view our findings indicate that memory impairment does not fully account for blindness phenomena.

Memory impairment is not sufficient for choice blindness to occur.

Science.gov (United States)

Sagana, Anna; Sauerland, Melanie; Merckelbach, Harald

2014-01-01

Choice blindness refers to the phenomenon that people can be easily misled about the choices they made in the recent past. The aim of this study was to explore the cognitive mechanisms underlying choice blindness. Specifically, we tested whether memory impairment may account for choice blindness. A total of N = 88 participants provided sympathy ratings on 10-point scales for 20 female faces. Subsequently, participants motivated some of their ratings. However, on three trials, they were presented with sympathy ratings that deviated from their original ratings by three full scale points. On nearly 41% of the trials, participants failed to detect (i.e., were blind) the manipulation. After a short interval, participants were informed that some trials had been manipulated and were asked to recall their original ratings. Participants adopted the manipulated outcome in only 3% of the trials. Furthermore, the extent to which the original ratings were accurately remembered was not higher for detected as compared with non-detected trials. From a theoretical point of view our findings indicate that memory impairment does not fully account for blindness phenomena.

Leading Causes of Blindness

Science.gov (United States)

... have cataracts. They are the leading cause of blindness in the world. By age 80, more than half of all people in the United States either will have a cataract or have had cataract surgery. Common symptoms are: Blurry vision Colors that seem faded Glare Not being able to ...

Prevalence and associated factors of corneal blindness in Ningxia in northwest China

Directory of Open Access Journals (Sweden)

Xun-Lun Sheng

2014-06-01

Full Text Available AIM:To describe the prevalence and demographic characteristics of corneal blindness in an urban and rural region of Ningxia, located in the northwest part of China.METHODS:A stratified, randomized sampling procedure was employed in the study, including urban and rural area of all age group. Visual acuity, anterior segment and ocular fundus were checked. Related factor of corneal disease, including age, gender, education status, ethnic group, location and occupation, were identified according to uniform customized protocol. An eye was defined to be corneal blindness if the visual acuity was <20/400 due to a corneal disease.RESULTS:Three thousand individuals (1290 from urban area and 1710 from rural area participated in the investigation, with a response rate of 80.380%. The prevalence of corneal blindness was 0.023% in both eyes and 0.733% in at least one eye. The blindness in at least one eye with varied causes was present in 106 participants (3.533% and in bilateral eyes in 34 participants (1.133%. The corneal diseases accounted for 20.754% of blindness in at least one eye and 20.588% of bilateral blindness. The prevalence of corneal disease was higher in older and Han ethnic group, especially those who occupied in agriculture and outdoor work. People with corneal blindness were more likely to be older and lower education. Rural population were more likely to suffer from bilateral corneal blindness than the urban population in ≥59-year group (χ2=6.716, P=0.019. Infectious, trauma and immune corneal disease were the three leading causes of corneal disease. Trauma corneal disease was more likely leading to blindness in one eye. However, infectious and immune corneal diseases make more contribution to the bilateral corneal blindness.CONCLUSION: Corneal blindness is a significant burden of in Ningxia population, encompassing a variety of corneal infections and trauma; the majority of those were avoidable. Health promotion strategies and good

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...

Amygdala activation for eye contact despite complete cortical blindness

NARCIS (Netherlands)

Burra, N.; Hervais-Adelman, A.; Kerzel, D.; Tamietto, M.; de Gelder, B.; Pegna, A.J.

2013-01-01

Cortical blindness refers to the loss of vision that occurs after destruction of the primary visual cortex. Although there is no sensory cortex and hence no conscious vision, some cortically blind patients show amygdala activation in response to facial or bodily expressions of emotion. Here we

Eye diseases and blindness in Adjumani refugee settlement camps ...

African Journals Online (AJOL)

Objectives: To determine the prevalence and causes of the blindness and ocular morbidity amongst Sudanese refugees; to prioritise and provide eye care services to the refugees and; to device administrative strategies and logistics of prevention and control of blinding diseases among the refugees. Design: A mobile ...

Modality-specific involvement of occipital cortex in Early Blind?

NARCIS (Netherlands)

van der Lubbe, Robert Henricus Johannes; van Mierlo, C.M.; Postma, A.

2008-01-01

What happens in occipital cortex when neuronal activity is no longer evoked by regular visual stimulation? Studying brain activity induced by tactile and auditory stimuli in the blind may provide an answer. Several studies indicate that occipital cortex in the blind is recruited in simple tasks,

Sucralfate gel as a radioprotector against radiation induced dermatitis in a hypo-fractionated schedule: a non-randomized study.

Science.gov (United States)

Kouloulias, V; Asimakopoulos, C; Tolia, M; Filippou, G; Platoni, K; Dilvoi, M; Beli, I; Georgakopoulos, J; Patatoukas, G; Kelekis, N

2013-04-01

External beam radiotherapy with high doses provokes many acute skin reactions, such as erythema and moist desquamation. Many topical preparations are used in radiation oncology departments in the skin care. Sucralfate humid gel, a colloidal physical form of the anti-ulcer drug sucralfate, promotes epithelial regeneration and activates cell proliferation. Based on this knowledge, we performed a non-randomized clinical trial to evaluate the efficacy of topical sucralfate gel in 30 breast cancer patients receiving postoperative accelerated hypofractionated photon beam therapy. The comparison was performed with 30 patients as historical controls. The acute reaction of the skin was significantly lower in the group receiving the sucralfate gel (p<0.05, Mann Whitney test), while 90% of the patients had no evidence of radiation induced skin toxicity. There was no sucralfate gel related toxicity reported by any patient in this study. More patients in a randomized way are needed for more definite results.

Causes of blindness and visual impairment in Latin America.

Science.gov (United States)

Furtado, João M; Lansingh, Van C; Carter, Marissa J; Milanese, María F; Peña, Brenda N; Ghersi, Hernán A; Bote, Paula L; Nano, María E; Silva, Juan C

2012-01-01

We review what is known in each country of the Latin American region with regards to blindness and visual impairment and make some comparisons to Hispanic populations in the United States. Prevalence of blindness varied from 1.1% in Argentina to 4.1% in Guatemala in people 50 years of age and older, with the major cause being cataract. Diabetic retinopathy and glaucoma are starting to make serious inroads, although epidemiological data are limited, and age-related macular degeneration is now a concern in some populations. Infectious diseases such as trachoma and onchocerciasis are quickly diminishing. Although progress has been made, retinopathy of prematurity remains the major cause of childhood blindness. If VISION 2020 is to succeed, many more epidemiological studies will be needed to set priorities, although some can be of the Rapid Assessment of Avoidable Blindness design. Developing the infrastructure for screening and treatment of ophthalmic disease in Latin America continues to be a challenge. Copyright © 2012 Elsevier Inc. All rights reserved.

Postural control in blind individuals: A systematic review.

Science.gov (United States)

Parreira, Rodolfo Borges; Grecco, Luanda André Collange; Oliveira, Claudia Santos

2017-09-01

Postural control (PC) requires the interaction of the three sensory systems for a good maintenance of the balance, and in blind people, lack of visual input can harm your PC. Thus the objective is to perform a literature review concerning role of sight in the maintenance of PC and the adaptation of brain structures when vision is absent. Studies were searched from Pubmed, and EMBASE that included individuals with congenital blindness. Articles studying person with acquired blindness or low vision was excluded from this review. 26 out of 322 articles were selected for review, and we found that 1) blind individuals exhibit PC deficits and that is compensated by the intensification of the remaining systems; 2) Neuroplastic adaptation occurs throughout the entire cerebral cortex; and 3) Sensorimotor stimulation and transcranial direct current stimulation seem to be a rehabilitation strategy. According to this review, the findings suggest that improved remaining sensations in the presence of adaptations and neuroplasticity, does not translate into better postural control performance. Regarding rehabilitation strategies, more studies are needed to show which therapeutic modality best contributes to postural control. Copyright © 2017 Elsevier B.V. All rights reserved.

Neural-network-based depth computation for blind navigation

Science.gov (United States)

Wong, Farrah; Nagarajan, Ramachandran R.; Yaacob, Sazali

2004-12-01

A research undertaken to help blind people to navigate autonomously or with minimum assistance is termed as "Blind Navigation". In this research, an aid that could help blind people in their navigation is proposed. Distance serves as an important clue during our navigation. A stereovision navigation aid implemented with two digital video cameras that are spaced apart and fixed on a headgear to obtain the distance information is presented. In this paper, a neural network methodology is used to obtain the required parameters of the camera which is known as camera calibration. These parameters are not known but obtained by adjusting the weights in the network. The inputs to the network consist of the matching features in the stereo pair images. A back propagation network with 16-input neurons, 3 hidden neurons and 1 output neuron, which gives depth, is created. The distance information is incorporated into the final processed image as four gray levels such as white, light gray, dark gray and black. Preliminary results have shown that the percentage errors fall below 10%. It is envisaged that the distance provided by neural network shall enable blind individuals to go near and pick up an object of interest.

Clinical governance breakdown: Australian cases of wilful blindness and whistleblowing.

Science.gov (United States)

Cleary, Sonja; Duke, Maxine

2017-01-01

After their attempts to have patient safety concerns addressed internally were ignored by wilfully blind managers, nurses from Bundaberg Base Hospital and Macarthur Health Service felt compelled to 'blow the whistle'. Wilful blindness is the human desire to prefer ignorance to knowledge; the responsibility to be informed is shirked. To provide an account of instances of wilful blindness identified in two high-profile cases of nurse whistleblowing in Australia. Critical case study methodology using Fay's Critical Social Theory to examine, analyse and interpret existing data generated by the Commissions of Inquiry held into Bundaberg Base Hospital and Macarthur Health Service patient safety breaches. All data was publicly available and assessed according to the requirements of unobtrusive research methods and secondary data analysis. Ethical considerations: Data collection for the case studies relied entirely on publicly available documentary sources recounting and detailing past events. Data from both cases reveal managers demonstrating wilful blindness towards patient safety concerns. Concerns were unaddressed; nurses, instead, experienced retaliatory responses leading to a 'social crisis' in the organisation and to whistleblowing. Managers tasked with clinical governance must be aware of mechanisms with the potential to blind them. The human tendency to favour positive news and avoid conflict is powerful. Understanding wilful blindness can assist managers' awareness of the competing emotions occurring in response to ethical challenges, such as whistleblowing.

Progression to Legal Blindness in Patients With Normal Tension Glaucoma: Hospital-Based Study.

Science.gov (United States)

Sawada, Akira; Rivera, Jonathan A; Takagi, Daisuke; Nishida, Takashi; Yamamoto, Tetsuya

2015-06-01

To determine the probability of an eye with normal tension glaucoma (NTG) progressing to legal blindness under standard ophthalmic care. Patients diagnosed with NTG (n = 382) between 1985 and 2007 at Gifu University Hospital were followed for at least 5 years under standard ophthalmic care. The collected data included the best-corrected visual acuity (BCVA), intraocular pressure (IOP), and visual field status. Blindness was defined as a BCVA of blindness in one or both eyes. The mean follow-up period after diagnosis was 13.3 ± 5.4 years with a range of 5.0 to 29.1 years. At diagnosis, 18 patients (4.7%) had unilateral blindness due to glaucoma. At final examination, 34 patients had progressed to unilateral blindness and 5 to bilateral blindness. The Kaplan-Meier life table analysis estimate for unilateral blindness was 5.8 ± 1.3% at 10 years and 9.9 ± 1.9% at 20 years. Similarly, that for bilateral blindness was 0.3 ± 0.3% at 10 years and 1.4 ± 0.8% at 20 years. A Cox proportional hazard model analysis showed that a lower initial BCVA (P blindness in at least one eye. The probability of blindness in eyes with NTG is much lower than previously reported in patients with high-tension glaucoma. Nevertheless, special care should be taken to follow NTG patients, and especially those with worse BCVA and more advanced visual field loss at diagnosis.

No Sensory Compensation for Olfactory Memory: Differences between Blind and Sighted People

Directory of Open Access Journals (Sweden)

Agnieszka Sorokowska

2017-12-01

Full Text Available Blindness can be a driving force behind a variety of changes in sensory systems. When vision is missing, other modalities and higher cognitive functions can become hyper-developed through a mechanism called sensory compensation. Overall, previous studies suggest that olfactory memory in blind people can be better than that of the sighted individuals. Better performance of blind individuals in other-sensory modalities was hypothesized to be a result of, among others, intense perceptual training. At the same time, if the superiority of blind people in olfactory abilities indeed results from training, their scores should not decrease with age to such an extent as among the sighted people. Here, this hypothesis was tested in a large sample of 94 blind individuals. Olfactory memory was assessed using the Test for Olfactory Memory, comprising episodic odor recognition (discriminating previously presented odors from new odors and two forms of semantic memory (cued and free identification of odors. Regarding episodic olfactory memory, we observed an age-related decline in correct hits in blind participants, but an age-related increase in false alarms in sighted participants. Further, age moderated the between-group differences for correct hits, but the direction of the observed effect was contrary to our expectations. The difference between blind and sighted individuals younger than 40 years old was non-significant, but older sighted individuals outperformed their blind counterparts. In conclusion, we found no positive effect of visual impairment on olfactory memory. We suggest that daily perceptual training is not enough to increase olfactory memory function in blind people.

No Sensory Compensation for Olfactory Memory: Differences between Blind and Sighted People.

Science.gov (United States)

Sorokowska, Agnieszka; Karwowski, Maciej

2017-01-01

Blindness can be a driving force behind a variety of changes in sensory systems. When vision is missing, other modalities and higher cognitive functions can become hyper-developed through a mechanism called sensory compensation. Overall, previous studies suggest that olfactory memory in blind people can be better than that of the sighted individuals. Better performance of blind individuals in other-sensory modalities was hypothesized to be a result of, among others, intense perceptual training. At the same time, if the superiority of blind people in olfactory abilities indeed results from training, their scores should not decrease with age to such an extent as among the sighted people. Here, this hypothesis was tested in a large sample of 94 blind individuals. Olfactory memory was assessed using the Test for Olfactory Memory, comprising episodic odor recognition (discriminating previously presented odors from new odors) and two forms of semantic memory (cued and free identification of odors). Regarding episodic olfactory memory, we observed an age-related decline in correct hits in blind participants, but an age-related increase in false alarms in sighted participants. Further, age moderated the between-group differences for correct hits, but the direction of the observed effect was contrary to our expectations. The difference between blind and sighted individuals younger than 40 years old was non-significant, but older sighted individuals outperformed their blind counterparts. In conclusion, we found no positive effect of visual impairment on olfactory memory. We suggest that daily perceptual training is not enough to increase olfactory memory function in blind people.

No Sensory Compensation for Olfactory Memory: Differences between Blind and Sighted People

Science.gov (United States)

Sorokowska, Agnieszka; Karwowski, Maciej

2017-01-01

Blindness can be a driving force behind a variety of changes in sensory systems. When vision is missing, other modalities and higher cognitive functions can become hyper-developed through a mechanism called sensory compensation. Overall, previous studies suggest that olfactory memory in blind people can be better than that of the sighted individuals. Better performance of blind individuals in other-sensory modalities was hypothesized to be a result of, among others, intense perceptual training. At the same time, if the superiority of blind people in olfactory abilities indeed results from training, their scores should not decrease with age to such an extent as among the sighted people. Here, this hypothesis was tested in a large sample of 94 blind individuals. Olfactory memory was assessed using the Test for Olfactory Memory, comprising episodic odor recognition (discriminating previously presented odors from new odors) and two forms of semantic memory (cued and free identification of odors). Regarding episodic olfactory memory, we observed an age-related decline in correct hits in blind participants, but an age-related increase in false alarms in sighted participants. Further, age moderated the between-group differences for correct hits, but the direction of the observed effect was contrary to our expectations. The difference between blind and sighted individuals younger than 40 years old was non-significant, but older sighted individuals outperformed their blind counterparts. In conclusion, we found no positive effect of visual impairment on olfactory memory. We suggest that daily perceptual training is not enough to increase olfactory memory function in blind people. PMID:29276494

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 the...

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.

The effect of biofeedback therapy on dyssynergic constipation in patients with or without Irritable Bowel Syndrome

OpenAIRE

Tannaz Ahadi; Faezeh Madjlesi; Bahar Mahjoubi; Rezvan Mirzaei; Bijan Forogh; Seyedeh Somayeh Daliri; Seyed Majid Derakhshandeh; Roxana Bazaz Behbahani; G Reza Raissi

2014-01-01

Background: The Rome II and III diagnostic criteria for dyssynergic defecation recommended the exclusion of irritable bowel syndrome (IBS). This study determined the effect of biofeedback therapy on dyssynergic constipation in patients with or without IBS. Materials and Methods: This study was a nonrandomized, single blinded, semi experimental study. Dyssynergic defecation patients with and without IBS were asked to undergo biofeedback therapy 8 sessions. The defecation dynamics and balloon e...

Real-time pedestrian detection in a Truck's blind spot camera

OpenAIRE

Van Beeck, Kristof; Goedemé, Toon

2014-01-01

In this paper we present a multi-pedestrian detection and tracking framework targeting a specific application: detecting vulnerable road users in a truck's blind spot zone. Research indicates that existing non-vision based safety solutions are not able to handle this problem completely. Therefore we aim to develop an active safety system which warns the truck driver if pedestrians are present in the truck's blind spot zone. Our system solely uses the vision input from the truck's blind spot c...

Advice from Blind Teachers on How to Teach Statistics to Blind Students

Science.gov (United States)

Godfrey, A. Jonathan R.; Loots, M. Theodor

2015-01-01

Blind students are bound to make up a very small part of the population most university lecturers will encounter during their careers. Research to date shows that good communication between staff and student improves the chances of a successful outcome for both parties. The research does show, however, that the exercise seems to be one of…

American Foundation for the Blind

Science.gov (United States)

... loss Text Size Smaller Type Larger Type Change Colors My AFB Search Donate to AFB Shop AFB ... and More Public Policy and Research Statistics on Blindness DirectConnect: Public Policy and Advocacy News Research Navigator: ...

Pattern of childhood blindness at a referral center in Saudi Arabia.

Science.gov (United States)

Tabbara, Khalid F; El-Sheikh, Hisham F; Shawaf, Shucri S

2005-01-01

An understanding of the causes of blindness and the magnitude of the problem is crucial in designing effective intervention and prevention programs. We undertook this retrospective review to determine the causes of childhood blindness at an eye referral center. We reviewed charts of children who presented between August 1997 and August 2003. All children had a complete ophthalmologic examination. Blindness was defined as a visual acuity < 20/400, visual impairment as visual acuity between 20/400 and 20/60, and visual loss as a visual acuity < 20/60. A total of 5217 children included 220 (59%) males and 152 (41%) females (age range 2 to 18 years, mean age, 10 years). One hundred twelve (2%) were blind and 260 (5%) had visual impairment. The most common causes of bilateral blindness included optic nerve diseases, retinal disorders, and cataract. The most common causes of unilateral blindness included trauma, retinal diseases, refractive errors, and optic nerve diseases. The most common causes of bilateral visual impairment included refractive errors, corneal diseases, retinal disorders, cataract, and congenital nystagmus. Genetically determined disorders were observed in 37 (70%) of 53 patients with bilateral blindness, and in 52 (56%) of 93 patients with bilateral visual impairment. The incidence of consanguinity among parents of children with acquired causes was 2 (3%) of 59 patients compared to 34 (38%) of 89 among genetically determined causes (P < 0.001). Genetically determined disorders continue to play an important role in the causation of childhood blindness among patients attending our referral center in Saudi Arabia. Genetic counseling, early eye screening of children and public education may help in the prevention of visual disorders in children.

A Study of Color Transformation on Website Images for the Color Blind

OpenAIRE

Siew-Li Ching; Maziani Sabudin

2010-01-01

In this paper, we study on color transformation method on website images for the color blind. The most common category of color blindness is red-green color blindness which is viewed as beige color. By transforming the colors of the images, the color blind can improve their color visibility. They can have a better view when browsing through the websites. To transform colors on the website images, we study on two algorithms which are the conversion techniques from RGB colo...

Cognitive aspects of haptic form recognition by blind and sighted subjects.

Science.gov (United States)

Bailes, S M; Lambert, R M

1986-11-01

Studies using haptic form recognition tasks have generally concluded that the adventitiously blind perform better than the congenitally blind, implicating the importance of early visual experience in improved spatial functioning. The hypothesis was tested that the adventitiously blind have retained some ability to encode successive information obtained haptically in terms of a global visual representation, while the congenitally blind use a coding system based on successive inputs. Eighteen blind (adventitiously and congenitally) and 18 sighted (blindfolded and performing with vision) subjects were tested on their recognition of raised line patterns when the standard was presented in segments: in immediate succession, or with unfilled intersegmental delays of 5, 10, or 15 seconds. The results did not support the above hypothesis. Three main findings were obtained: normally sighted subjects were both faster and more accurate than the other groups; all groups improved in accuracy of recognition as a function of length of interstimulus interval; sighted subjects tended to report using strategies with a strong verbal component while the blind tended to rely on imagery coding. These results are explained in terms of information-processing theory consistent with dual encoding systems in working memory.

Retention of high tactile acuity throughout the life span in blindness.

Science.gov (United States)

Legge, Gordon E; Madison, Cindee; Vaughn, Brenna N; Cheong, Allen M Y; Miller, Joseph C

2008-11-01

Previous studies of tactile acuity on the fingertip, using passive touch, have demonstrated an age-related decline in spatial resolution for both sighted and blind subjects. We have reexamined this age dependence with two newly designed tactile-acuity charts that require active exploration of the test symbols. One chart used dot patterns similar to braille, and the other used embossed Landolt rings. Groups of blind braille readers and sighted subjects ranging from 12 to 85 years old were tested in two experiments. We replicated previous findings for sighted subjects by showing an age-related decrease in tactile acuity by nearly 1% per year. Surprisingly, the blind subjects retained high acuity into old age, showing no age-related decline. For the blind subjects, tactile acuity did not correlate with braille reading speed, the amount of daily reading, or the age at which braille was learned. We conclude that when measured with active touch, blind subjects retain high tactile acuity into old age, unlike their aging sighted peers. We propose that blind people's use of active touch in daily activities, not specifically braille reading, results in preservation of tactile acuity across the life span.

Design of An Electronic Narrator on Assistant Robot for Blind People

Directory of Open Access Journals (Sweden)

Ardiansyah Rizqi Andry

2016-01-01

Full Text Available Many personal service robot is developed to help blind people in daily life, such as room cleaning, for navigating, object finding, reading and other activities. In this context, the present work focuses the development of an image-to-speech application for the blind. The project is called Design of An Electronic Narrator on Assistant Robot for Blind People, and the final purpose is the design of an electronic narrator application on personal service robot that helps to narrate a text on a book, magazine, a sheet of paper etc to a blind person. To achieve that, a Raspberry pi board, a light sensor, OpenCV computer vision library, Tesseract OCR (Optical Character Recognition library, eSpeak Text-to-Speech Synthesizer (TTS library are integrated, which is enables the blind person to hear a narration from text on a book, magazine, a sheet etc.

Sequential blind identification of underdetermined mixtures using a novel deflation scheme.

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Zhang, Mingjian; Yu, Simin; Wei, Gang

2013-09-01

In this brief, we consider the problem of blind identification in underdetermined instantaneous mixture cases, where there are more sources than sensors. A new blind identification algorithm, which estimates the mixing matrix in a sequential fashion, is proposed. By using the rank-1 detecting device, blind identification is reformulated as a constrained optimization problem. The identification of one column of the mixing matrix hence reduces to an optimization task for which an efficient iterative algorithm is proposed. The identification of the other columns of the mixing matrix is then carried out by a generalized eigenvalue decomposition-based deflation method. The key merit of the proposed deflation method is that it does not suffer from error accumulation. The proposed sequential blind identification algorithm provides more flexibility and better robustness than its simultaneous counterpart. Comparative simulation results demonstrate the superior performance of the proposed algorithm over the simultaneous blind identification algorithm.

A Virtual Environment for People Who Are Blind - A Usability Study.

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Lahav, O; Schloerb, D W; Kumar, S; Srinivasan, M A

2012-01-01

For most people who are blind, exploring an unknown environment can be unpleasant, uncomfortable, and unsafe. Over the past years, the use of virtual reality as a learning and rehabilitation tool for people with disabilities has been on the rise. This research is based on the hypothesis that the supply of appropriate perceptual and conceptual information through compensatory sensorial channels may assist people who are blind with anticipatory exploration. In this research we developed and tested the BlindAid system, which allows the user to explore a virtual environment. The two main goals of the research were: (a) evaluation of different modalities (haptic and audio) and navigation tools, and (b) evaluation of spatial cognitive mapping employed by people who are blind. Our research included four participants who are totally blind. The preliminary findings confirm that the system enabled participants to develop comprehensive cognitive maps by exploring the virtual environment.

Improving Sleep for Hospitalized Antepartum Patients: A Non-Randomized Controlled Pilot Study.

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Lee, Kathryn A; Gay, Caryl L

2017-12-15

To evaluate feasibility and efficacy of a hospital-based protocol for improving sleep in high- risk antepartum patients. Sleep measures were compared during 1 week of hospitalization before and after implementing a Sleep Improvement Protocol for Antepartum Patients (SIP-AP). A non-randomized convenience sample of usual care controls was compared to a subsequent intervention sample after the protocol was implemented. Women were eligible if they spoke English, were medically stable, pregnant for at least 20 weeks, and hospitalized at least 24 hours; 25 pregnant women had sufficient data for analyses (11 controls, 14 intervention). Sleep was assessed in 3 ways: the Pittsburgh Sleep Quality Index was completed after obtaining consent to estimate sleep quality prior to hospital admission; sleep diary completed each hospital day; and General Sleep Disturbance Scale completed at 7 days or prior to hospital discharge. Symptoms that could affect sleep were assessed with the Memorial Symptom Assessment Scale. Both groups recorded similar sleep duration (7 hours) but the intervention group had fewer symptoms and significantly ( P = .015) lower sleep disturbance scores (53.1 ± 14.5) than controls (71.9 ± 18.8). Participant feedback about the intervention was positive, although adherence to components of the intervention protocol was variable. This pilot study provides evidence of the feasibility and preliminary efficacy of the SIP-AP intervention for reducing symptoms and improving sleep of antepartum patients during hospitalization. Further detailed evaluation of specific components of this protocol is warranted, and other types of hospitalized patients may benefit from unit-based modifications to this SIP-AP protocol. © 2017 American Academy of Sleep Medicine

Warming Endotracheal Tube in Blind Nasotracheal Intubation throughout Maxillofacial Surgeries

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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.

Sight and blindness in the same person: Gating in the visual system.

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Strasburger, Hans; Waldvogel, Bruno

2015-12-01

We present the case of a patient having dissociative identity disorder (DID) who-after 15 years of misdiagnosed cortical blindness--step-by-step regained sight during psychotherapeutic treatment. At first only a few personality states regained vision whereas others remained blind. This could be confirmed by electrophysiological measurement, in which visual evoked potentials (VEPs) were absent in the blind personality states but were normal and stable in the seeing states. A switch between these states could happen within seconds. We assume a top-down modulation of activity in the primary visual pathway as a neural basis of such psychogenic blindness, possibly at the level of the thalamus. VEPs therefore do not allow separating psychogenic blindness from organic disruption of the visual pathway. In summary, psychogenic blindness seems to suppress visual information at an early neural stage. © 2015 The Institute of Psychology, Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

Lexical References to Sensory Modalities in Verbal Descriptions of People and Objects by Congenitally Blind, Late Blind and Sighted Adults