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.

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

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.

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.

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.

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.

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.

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…

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.

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...

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.

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.

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.

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.

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....

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

Directory of Open Access Journals (Sweden)

F Ezoddini - Ardakani

2006-01-01

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

Lower Columbia River Terminal Fisheries Research Project : Final Environmental Assessment.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration.

1995-04-01

This notice announces BPA`S`s decision to fund the Oregon Department of Fish and Wildlife (ODFW), the Washington Department of Fish and Wildlife (WDFW), and the Clatsop Economic Development Committee for the Lower Columbia River Terminal Fisheries Research Project (Project). The Project will continue the testing of various species/stocks, rearing regimes, and harvest options for terminal fisheries, as a means to increase lower river sport and commercial harvest of hatchery fish, while providing both greater protection of weaker wild stocks and increasing the return of upriver salmon runs to potential Zone 6 Treaty fisheries. The Project involves relocating hatchery smolts to new, additional pen locations in three bays/sloughs in the lower Columbia River along both the Oregon and Washington sides. The sites are Blind Slough and Tongue Point in Clatsop County, Oregon, and Grays Bay/Deep River, Wahkiakum County, Washington. The smolts will be acclimated for various lengths of time in the net pens and released from these sites. The Project will expand upon an existing terminal fisheries project in Youngs Bay, Oregon. The Project may be expanded to other sites in the future, depending on the results of this initial expansion. BPA`S has determined the project is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an environmental impact statement is not required, and BPA`S is issuing this FONSI.

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…

Columbia River: Terminal fisheries research project. 1994 Annual report

Energy Technology Data Exchange (ETDEWEB)

Hirose, P.; Miller, M.; Hill, J.

1996-12-01

Columbia River terminal fisheries have been conducted in Youngs Bay, Oregon, since the early 1960`s targeting coho salmon produced at the state facility on the North Fork Klaskanine River. In 1977 the Clatsop County Economic Development Council`s (CEDC) Fisheries Project began augmenting the Oregon Department of Fish and Wildlife production efforts. Together ODFW and CEDC smolt releases totaled 5,060,000 coho and 411,300 spring chinook in 1993 with most of the releases from the net pen acclimation program. During 1980-82 fall commercial terminal fisheries were conducted adjacent to the mouth of Big Creek in Oregon. All past terminal fisheries were successful in harvesting surplus hatchery fish with minimal impact on nonlocal weak stocks. In 1993 the Northwest Power Planning Council recommended in its` Strategy for Salmon that terminal fishing sites be identified and developed. The Council called on the Bonneville Power Administration to fund a 10-year study to investigate the feasibility of creating and expanding terminal known stock fisheries in the Columbia River Basin. The findings of the initial year of the study are included in this report. The geographic area considered for study extends from Bonneville Dam to the river mouth. The initial year`s work is the beginning of a 2-year research stage to investigate potential sites, salmon stocks, and methodologies; a second 3-year stage will focus on expansion in Youngs Bay and experimental releases into sites with greatest potential; and a final 5-year phase establishing programs at full capacity at all acceptable sites. After ranking all possible sites using five harvest and five rearing criteria, four sites in Oregon (Tongue Point, Blind Slough, Clifton Channel and Wallace Slough) and three in Washington (Deep River, Steamboat Slough and Cathlamet Channel) were chosen for study.

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

Directory of Open Access Journals (Sweden)

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.

Future trends in global blindness

Directory of Open Access Journals (Sweden)

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

Directory of Open Access Journals (Sweden)

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.

Choice blindness in financial decision making

Directory of Open Access Journals (Sweden)

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

Directory of Open Access Journals (Sweden)

Jaime Sánchez

2008-01-01

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

What It's Like to Be Color Blind

Science.gov (United States)

... 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

Directory of Open Access Journals (Sweden)

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.

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.

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...

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...

Columbia River Stock Identification Study; Validation of Genetic Method, 1980-1981 Final Report.

Energy Technology Data Exchange (ETDEWEB)

Milner, George B.; Teel, David J.; Utter, Fred M. (Northwest and Alaska Fisheries Science Center, Coastal Zone and Estuarine Studies Division, Seattle, WA)

1981-06-01

The reliability of a method for obtaining maximum likelihood estimate of component stocks in mixed populations of salmonids through the frequency of genetic variants in a mixed population and in potentially contributing stocks was tested in 1980. A data base of 10 polymorphic loci from 14 hatchery stocks of spring chinook salmon of the Columbia River was used to estimate proportions of these stocks in four different blind'' mixtures whose true composition was only revealed subsequent to obtaining estimates. The accuracy and precision of these blind tests have validated the genetic method as a valuable means for identifying components of stock mixtures. Properties of the genetic method were further examined by simulation studies using the pooled data of the four blind tests as a mixed fishery. Replicated tests with samples sizes between 100 and 1,000 indicated that actual standard deviations on estimated contributions were consistently lower than calculated standard deviations; this difference diminished as sample size increased. It is recommended that future applications of the method be preceded by simulation studies that will identify appropriate levels of sampling required for acceptable levels of accuracy and precision. Variables in such studies include the stocks involved, the loci used, and the genetic differentiation among stocks. 8 refs., 6 figs., 4 tabs.

River water pollution condition in upper part of Brantas River and Bengawan Solo River

Science.gov (United States)

Roosmini, D.; Septiono, M. A.; Putri, N. E.; Shabrina, H. M.; Salami, I. R. S.; Ariesyady, H. D.

2018-01-01

Wastewater and solid waste from both domestic and industry have been known to give burden on river water quality. Most of river water quality problem in Indonesia has start in the upper part of river due to anthropogenic activities, due to inappropriate land use management including the poor wastewater infrastructure. Base on Upper Citarum River Water pollution problem, it is interesting to study the other main river in Java Island. Bengawan Solo River and Brantas River were chosen as the sample in this study. Parameters assessed in this study are as follows: TSS, TDS, pH, DO, and hexavalent chromium. The status of river water quality are assess using STORET method. Based on (five) parameters, STORET value showed that in Brantas River, Pagerluyung monitoring point had the worst quality relatively compared to other monitoring point in Brantas River with exceeding copper, lead and tin compared to the stream standard in East Java Provincial Regulation No. 2 in 2008. Brantas River was categorized as lightly polluted river based on monitoring period 2011-2015 in 5 monitoring points, namely Pendem, Sengguruh, Kademangan, Meritjan and Kertosono.

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.

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.

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.

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…

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

OpenAIRE

Fereshteh Kordestani; Azam Daneshfar; Davood Roustaee

2014-01-01

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

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…

River-corridor habitat dynamics, Lower Missouri River

Science.gov (United States)

Jacobson, Robert B.

2010-01-01

Intensive management of the Missouri River for navigation, flood control, and power generation has resulted in substantial physical changes to the river corridor. Historically, the Missouri River was characterized by a shifting, multithread channel and abundant unvegetated sandbars. The shifting channel provided a wide variety of hydraulic environments and large areas of connected and unconnected off-channel water bodies.Beginning in the early 1800s and continuing to the present, the channel of the Lower Missouri River (downstream from Sioux City, Iowa) has been trained into a fast, deep, single-thread channel to stabilize banks and maintain commercial navigation. Wing dikes now concentrate the flow, and revetments and levees keep the channel in place and disconnect it from the flood plain. In addition, reservoir regulation of the Missouri River upstream of Yankton, South Dakota, has substantially changed the annual hydrograph, sediment loads, temperature regime, and nutrient budgets.While changes to the Missouri River have resulted in broad social and economic benefits, they have also been associated with loss of river-corridor habitats and diminished populations of native fish and wildlife species. Today, Missouri River stakeholders are seeking ways to restore some natural ecosystem benefits of the Lower Missouri River without compromising traditional economic uses of the river and flood plain.

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…

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.

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

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.

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.

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.

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 ...

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...

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

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?

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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.

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.

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.

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?

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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.

[Health assessment of river ecosystem in Haihe River Basin, China].

Science.gov (United States)

Hao, Li-Xia; Sun, Ran-Hao; Chen, Li-Ding

2014-10-01

With the development of economy, the health of river ecosystem is severely threatened because of the increasing effects of human activities on river ecosystem. In this paper, the authors assessed the river ecosystem health in aspects of chemical integrity and biological integrity, using the criterion in water quality, nutrient, and benthic macroinvertebrates of 73 samples in Haihe River Basin. The research showed that the health condition of river ecosystem in Haihe River Basin was bad overall since the health situation of 72. 6% of the samples was "extremely bad". At the same time, the health situation in Haihe River Basin exhibited obvious regional gathering effect. We also found that the river water quality was closely related to human activities, and the eutrophication trend of water body was evident in Haihe River Basin. The biodiversity of the benthic animal was low and lack of clean species in the basin. The indicators such as ammonia nitrogen, total nitrogen and total phosphorus were the key factors that affected the river ecosystem health in Haihe River Basin, so the government should start to curb the deterioration of river ecosystem health by controlling these nutrients indicators. For river ecosystem health assessment, the multi-factors comprehensive evaluation method was superior to single-factor method.

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.

Restrictive partially blind signature for resource-constrained information systems

NARCIS (Netherlands)

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

2010-01-01

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

Ask a Scientist: What is Color Blindness?

Medline Plus

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?

Medline Plus

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 ( ...

River habitat assessment for ecological restoration of Wei River Basin, China.

Science.gov (United States)

Yang, Tao; Wang, Shuo; Li, Xiaoping; Wu, Ting; Li, Li; Chen, Jia

2018-04-11

As an important composition component of river ecosystems, river habitats must undergo quality assessment to potentially provide scientific basis for river ecological restoration. Substrate composition, habitat complexity, bank erosion degree, river meandering degree, human activity intensity, vegetation buffer width, water quality, and water condition were determined as indicators for river habitat assessment. The comprehensive habitat quality index (CHQI) was established for the Wei River Basin. In addition, the indicator values were determined on the basis of a field investigation at 12 national hydrological stations distributed across the Wei, Jing, and Beiluo Rivers. The analytic hierarchy process was used to determine the indicator weights and thus distinguish the relative importance of the assessment indicator system. Results indicated that the average CHQIs for the Wei, Jing, and Beiluo Rivers were 0.417, 0.508, and 0.304, respectively. The river habitat quality for the three rivers was well. As for the whole river basin, the river habitat quality for 25% of the cross section was very well, the other 25% was well, and the 50% remaining was in critical state. The river habitat quality of the Jing River was better than that of the Wei and Beiluo Rivers.

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.

Science.gov (United States)

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…

76 FR 51887 - Safety Zone; Patuxent River, Patuxent River, MD

Science.gov (United States)

2011-08-19

...-AA00 Safety Zone; Patuxent River, Patuxent River, MD AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone during the ``NAS Patuxent River... held over certain waters of the Patuxent River adjacent to Patuxent River, Maryland from September 1...

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...

Onchocerciasis (River Blindness) FAQs

Science.gov (United States)

... an infection caused by the parasitic worm Onchocerca volvulus , spread by the bite of an infected Simulium ... indicate that you are still infected with O. volvulus . What is the treatment for onchocerciasis? There 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

Science.gov (United States)

... 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

Economic burden of glaucoma in Rivers State, Nigeria.

Science.gov (United States)

Adio, Adedayo O; Onua, Alfred A

2012-01-01

Primary open angle glaucoma is reported to blind 150,000 people in the Nigerian population and over 7000 in Rivers State, and requires constant follow-up. Compliance is a challenge, given that most inhabitants live below the poverty line. This study was performed to determine how Nigerian patients are affected economically by the disease. Consecutive adult patients attending the eye clinic of the University of Port Harcourt Teaching Hospital, Rivers State, Nigeria, with a diagnosis of primary open angle glaucoma and on outpatient antiglaucoma treatment in the first 6 months of 2006, were recruited for the study. The lowest paid government worker was on USD50 (N7500.00) per month and the gross domestic product per capita was USD1150 for the period under review. We enrolled 120 consecutive patients of mean age 52.7 ± 10.4 years, with a male to female ratio of 2:3. The most common occupations were in the civil service (n = 56, 46.7%). All participants were on topical antiglaucoma treatment. The average cost of medical antiglaucoma medication was N6000 (USD40) per month. Computed to include indirect costs, including medical laboratory tests, transportation, and care by patient escorts, an average sum of USD105.4 (N15,810) was spent by each patient per month. Most of the patients (73.3%) were responsible for their own treatment costs. No patient accepted the cheaper option of surgery (USD275.4, N41,310). Eighty of the patients (66.7%) visited our eye clinic monthly. Direct and indirect loss to the economy was USD3,064587 per annum from those already blind. This was in addition to the USD 4.1 million being spent yearly on medical treatment by those who were visually impaired by glaucoma. Middle-income earners spent over 50% of their monthly income and low-income earners spend all their monthly earnings on treatment for glaucoma. This situation often resulted in noncompliance with treatment and hospital follow-up visits. To reduce the economic burden of glaucoma

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 ...

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 ...

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...

50 CFR 226.205 - Critical habitat for Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River...

Science.gov (United States)

2010-10-01

... salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. 226.205 Section... Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. The following areas consisting of the water, waterway bottom, and adjacent riparian zone of...

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.

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.

Numerical modelling of river processes: flow and river bed deformation

NARCIS (Netherlands)

Tassi, P.A.

2007-01-01

The morphology of alluvial river channels is a consequence of complex interaction among a number of constituent physical processes, such as flow, sediment transport and river bed deformation. This is, an alluvial river channel is formed from its own sediment. From time to time, alluvial river

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.

33 CFR 117.734 - Navesink River (Swimming River).

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Navesink River (Swimming River). 117.734 Section 117.734 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... (Swimming River). The Oceanic Bridge, mile 4.5, shall open on signal; except that, from December 1 through...

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 ...

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.

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…

Operation of river systems. The Otra river

International Nuclear Information System (INIS)

Harby, A.; Vaskinn, K.A.; Wathne, M.; Heggenes, J.; Saltveit, S.J.

1993-12-01

The purpose of the project described in this report was to prepare an operative tool for making decisions about the operation of the power system on the river Otra (Norway) with regard to how this operation might affect the various users of the river system. Above all this affects fish, outdoor life and esthetic values. The connection between water quality and volume of discharge has been examined in a sub project. How suitable parts of the river are as habitats for trout has been simulated on a computer. From field investigation it is concluded that near the Steinfoss power station the physical conditions for trout depend on the operation of the river system. Outdoor life is not much affected downstream Vikeland. 11 refs., 22 figs., 2 tabs

[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.

33 CFR 165.150 - New Haven Harbor, Quinnipiac River, Mill River.

Science.gov (United States)

2010-07-01

... River, Mill River. 165.150 Section 165.150 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... New Haven Harbor, Quinnipiac River, Mill River. (a) The following is a regulated navigation area: The... 303°T to point D at the west bank of the mouth of the Mill River 41°18′05″ N, 72°54′23″ W thence south...

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...

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.

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.

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.

Many rivers to cross. Cross border co-operation in river management

NARCIS (Netherlands)

Verwijmeren, J.A.; Wiering, M.A.

2007-01-01

River basin management is a key concept in contemporary water policy. Since the management of rivers is best designed and implemented at the scale of the river basin, it seems obvious that we should not confine ourselves to administrative or geographical borders. In other words, river basin

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.

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.

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.

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.

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.

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...

[Nutrients Input Characteristics of the Yangtze River and Wangyu River During the "Water Transfers on Lake Taihu from the Yangtze River"].

Science.gov (United States)

Pan, Xiao-xue; Ma, Ying-qun; Qin, Yan-wen; Zou, Hua

2015-08-01

Overall 20 surface water samples were collected from the Yangtze River, the Wangyu River and the Gonghu Bay (Lake Taihu) to clarify the pollution characteristics of nitrogen and phosphorus during 2 sample stages of "Water Transfers on Lake Taihu from the Yangtze River" in August and December of 2013 respectively. The results showed that the mass concentrations of NO2- -N, NO3- -N, NH4+ -N and TN in the Gonghu Bay were lower than those of the Yangtze River and Wangyu River during the 2 water transfer processes. However, there was higher level of DON content in the Gonghu Bay than that of the Yangtze River and Wangyu River. The percentages of various N species showed that NO3- -N was the major N species in the Yangtze River and Wangyu River during the 2 water transfer processes. TP contents in samples collected from the Yangtze River displayed a constant trend compared with the Wangyu River. However, the percentages of various P species were different with each other during the 2 water transfer processes. Mass concentrations of DON and TP in surface water in August were higher than those in December and the contents of NO3- -N and TDP were lower in August than those in December. In general, NO3- -N and TPP were the main N and P species in Wangyu River from the Yangtze River. NO3- -N, PO4(3-) -P and TPP were the main N and P species in Gonghu Bay from Wangyu River during the 2 water transfer processes.

River-Based Experiential Learning: the Bear River Fellows Program

Science.gov (United States)

Rosenberg, D. E.; Shirley, B.; Roark, M. F.

2012-12-01

The Department of Civil and Environmental Engineering, Outdoor Recreation, and Parks and Recreation programs at Utah State University (USU) have partnered to offer a new, unique river-based experiential learning opportunity for undergraduates called the Bear River Fellows Program. The program allows incoming freshmen Fellows to experience a river first hand during a 5-day/4-night river trip on the nearby Bear River two weeks before the start of their first Fall semester. As part of the program, Fellows will navigate the Bear River in canoes, camp along the banks, interact with local water and environmental managers, collect channel cross section, stream flow, vegetation cover, and topological complexity data, meet other incoming freshmen, interact with faculty and graduate students, develop boating and leadership skills, problem solve, and participate as full members of the trip team. Subsequently, Fellows will get paid as undergraduate researchers during their Fall and Spring Freshman semesters to analyze, synthesize, and present the field data they collect. The program is a collaborative effort between two USU academic units and the (non-academic) division of Student Services and supports a larger National Science Foundation funded environmental modelling and management project for the lower Bear River, Utah watershed. We have advertised the program via Facebook and emails to incoming USU freshmen, received 35 applications (60% women), and accepted 5 Fellows into the program (3 female and 2 male). The river trip departs August 14, 2012. The poster will overview the Bear River Fellows Program and present qualitative and preliminary outcomes emerging from the trip and Fellows' work through the Fall semester with the field data they collect. We will also undertake more rigorous and longer longitudinal quantitative evaluation of Program outcomes (for example, in problem-solving and leadership) both in Spring 2013 and in subsequent 2013 and 2014 offerings of the

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...

Comparative Research on River Basin Management in the Sagami River Basin (Japan and the Muda River Basin (Malaysia

Directory of Open Access Journals (Sweden)

Lay Mei Sim

2018-05-01

Full Text Available In the world, river basins often interwoven into two or more states or prefectures and because of that, disputes over water are common. Nevertheless, not all shared river basins are associated with water conflicts. Rivers in Japan and Malaysia play a significant role in regional economic development. They also play a significant role as water sources for industrial, domestic, agricultural, aquaculture, hydroelectric power generation, and the environment. The research aim is to determine the similarities and differences between the Sagami and Muda River Basins in order to have a better understanding of the governance needed for effectively implementing the lessons drawn from the Sagami River Basin for improving the management of the Muda River Basin in Malaysia. This research adopts qualitative and quantitative approaches. Semi-structured interviews were held with the key stakeholders from both basins and show that Japan has endeavored to present policy efforts to accommodate the innovative approaches in the management of their water resources, including the establishment of a river basin council. In Malaysia, there is little or no stakeholder involvement in the Muda River Basin, and the water resource management is not holistic and is not integrated as it should be. Besides that, there is little or no Integrated Resources Water Management, a pre-requisite for sustainable water resources. The results from this comparative study concluded that full support and participation from public stakeholders (meaning the non-government and non-private sector stakeholders is vital for achieving sustainable water use in the Muda River Basin. Integrated Water Resources Management (IWRM approaches such as the introduction of payments for ecosystems services and the development of river basin organization in the Muda River Basin should take place in the spirit of political willingness.

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.

RiverCare: towards self-sustaining multifunctional rivers

Science.gov (United States)

Augustijn, Denie; Schielen, Ralph; Hulscher, Suzanne

2014-05-01

Rivers are inherently dynamic water systems involving complex interactions among hydrodynamics, morphology and ecology. In many deltas around the world lowland rivers are intensively managed to meet objectives like safety, navigation, hydropower and water supply. With the increasing pressure of growing population and climate change it will become even more challenging to reach or maintain these objectives and probably also more demanding from a management point of view. In the meantime there is a growing awareness that rivers are natural systems and that, rather than further regulation works, the dynamic natural processes should be better utilized (or restored) to reach the multifunctional objectives. Currently many integrated river management projects are initiated all over the world, in large rivers as well as streams. Examples of large scale projects in the Netherlands are 'Room for the River' (Rhine), the 'Maaswerken' (Meuse), the Deltaprogramme and projects originating from the European Water Framework Directive (WFD). These projects include innovative measures executed never before on this scale and include for example longitudinal training dams, side channels, removal of bank protection, remeandering of streams, dredging/nourishment and floodplain rehabilitation. Although estimates have been made on the effects of these measures for many of the individual projects, the overall effects on the various management objectives remains uncertain, especially if all projects are considered in connection. For all stakeholders with vested interests in the river system it is important to know how that system evolves at intermediate and longer time scales (10 to 100 years) and what the consequences will be for the various river functions. If the total, integrated response of the system can be predicted, the system may be managed in a more effective way, making optimum use of natural processes. In this way, maintenance costs may be reduced, the system remains more natural

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.

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.

Bathymetric surveys of the Neosho River, Spring River, and Elk River, northeastern Oklahoma and southwestern Missouri, 2016–17

Science.gov (United States)

Hunter, Shelby L.; Ashworth, Chad E.; Smith, S. Jerrod

2017-09-26

In February 2017, the Grand River Dam Authority filed to relicense the Pensacola Hydroelectric Project with the Federal Energy Regulatory Commission. The predominant feature of the Pensacola Hydroelectric Project is Pensacola Dam, which impounds Grand Lake O’ the Cherokees (locally called Grand Lake) in northeastern Oklahoma. Identification of information gaps and assessment of project effects on stakeholders are central aspects of the Federal Energy Regulatory Commission relicensing process. Some upstream stakeholders have expressed concerns about the dynamics of sedimentation and flood flows in the transition zone between major rivers and Grand Lake O’ the Cherokees. To relicense the Pensacola Hydroelectric Project with the Federal Energy Regulatory Commission, the hydraulic models for these rivers require high-resolution bathymetric data along the river channels. In support of the Federal Energy Regulatory Commission relicensing process, the U.S. Geological Survey, in cooperation with the Grand River Dam Authority, performed bathymetric surveys of (1) the Neosho River from the Oklahoma border to the U.S. Highway 60 bridge at Twin Bridges State Park, (2) the Spring River from the Oklahoma border to the U.S. Highway 60 bridge at Twin Bridges State Park, and (3) the Elk River from Noel, Missouri, to the Oklahoma State Highway 10 bridge near Grove, Oklahoma. The Neosho River and Spring River bathymetric surveys were performed from October 26 to December 14, 2016; the Elk River bathymetric survey was performed from February 27 to March 21, 2017. Only areas inundated during those periods were surveyed.The bathymetric surveys covered a total distance of about 76 river miles and a total area of about 5 square miles. Greater than 1.4 million bathymetric-survey data points were used in the computation and interpolation of bathymetric-survey digital elevation models and derived contours at 1-foot (ft) intervals. The minimum bathymetric-survey elevation of the Neosho

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.

Classification of Tropical River Using Chemometrics Technique: Case Study in Pahang River, Malaysia

International Nuclear Information System (INIS)

Mohd Khairul Amri Kamarudin; Mohd Ekhwan Toriman; Nur Hishaam Sulaiman

2015-01-01

River classification is very important to know the river characteristic in study areas, where this database can help to understand the behaviour of the river. This article discusses about river classification using Chemometrics techniques in mainstream of Pahang River. Based on river survey, GIS and Remote Sensing database, the chemometric analysis techniques have been used to identify the cluster on the Pahang River using Hierarchical Agglomerative Cluster Analysis (HACA). Calibration and validation process using Discriminant Analysis (DA) has been used to confirm the HACA result. Principal Component Analysis (PCA) study to see the strong coefficient where the Pahang River has been classed. The results indicated the main of Pahang River has been classed to three main clusters as upstream, middle stream and downstream. Base on DA analysis, the calibration and validation model shows 100 % convinced. While the PCA indicates there are three variables that have a significant correlation, domination slope with R"2 0.796, L/D ratio with R"2 -0868 and sinuosity with R"2 0.557. Map of the river classification with moving class also was produced. Where the green colour considered in valley erosion zone, yellow in a low terrace of land near the channels and red colour class in flood plain and valley deposition zone. From this result, the basic information can be produced to understand the characteristics of the main Pahang River. This result is important to local authorities to make decisions according to the cluster or guidelines for future study in Pahang River, Malaysia specifically and for Tropical River generally. The research findings are important to local authorities by providing basic data as a guidelines to the integrated river management at Pahang River, and Tropical River in general. (author)

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

Science.gov (United States)

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

Directory of Open Access Journals (Sweden)

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...

River Corridor Easements

Data.gov (United States)

Vermont Center for Geographic Information — A River Corridor Easement (RCE) is an area of conserved land adjacent to a river or stream that was conserved to permanently protect the lateral area the river needs...

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...

Compromised Rivers: Understanding Historical Human Impacts on Rivers in the Context of Restoration

Directory of Open Access Journals (Sweden)

Ellen Wohl

2005-12-01

Full Text Available A river that preserves a simplified and attractive form may nevertheless have lost function. Loss of function in these rivers can occur because hydrologic and geomorphic processes no longer create and maintain the habitat and natural disturbance regimes necessary for ecosystem integrity. Recognition of compromised river function is particularly important in the context of river restoration, in which the public perception of a river's condition often drives the decision to undertake restoration as well as the decision about what type of restoration should be attempted. Determining the degree to which a river has been altered from its reference condition requires a knowledge of historical land use and the associated effects on rivers. Rivers of the Front Range of the Colorado Rocky Mountains in the United States are used to illustrate how historical land uses such as beaver trapping, placer mining, tie drives, flow regulation, and the construction of transportation corridors continue to affect contemporary river characteristics. Ignorance of regional land use and river history can lead to restoration that sets unrealistic goals because it is based on incorrect assumptions about a river's reference condition or about the influence of persistent land-use effects.

Crossmodal Recruitment of the Ventral Visual Stream in Congenital Blindness

Directory of Open Access Journals (Sweden)

Maurice Ptito

2012-01-01

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

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.

Geomorphology and river dynamics of the lower Copper River, Alaska

Science.gov (United States)

Brabets, Timothy P.; Conaway, Jeffrey S.

2009-01-01

Located in south-central Alaska, the Copper River drains an area of more than 24,000 square miles. The average annual flow of the river near its mouth is 63,600 cubic feet per second, but is highly variable between winter and summer. In the winter, flow averages approximately 11,700 cubic feet per second, and in the summer, due to snowmelt, rainfall, and glacial melt, flow averages approximately 113,000 cubic feet per second, an order of magnitude higher. About 15 miles upstream of its mouth, the Copper River flows past the face of Childs Glacier and enters a large, broad, delta. The Copper River Highway traverses this flood plain, and in 2008, 11 bridges were located along this section of the highway. The bridges cross several parts of the Copper River and in recent years, the changing course of the river has seriously damaged some of the bridges.Analysis of aerial photography from 1991, 1996, 2002, 2006, and 2007 indicates the eastward migration of a channel of the Copper River that has resulted in damage to the Copper River Highway near Mile 43.5. Migration of another channel in the flood plain has resulted in damage to the approach of Bridge 339. As a verification of channel change, flow measurements were made at bridges along the Copper River Highway in 2005–07. Analysis of the flow measurements indicate that the total flow of the Copper River has shifted from approximately 50 percent passing through the bridges at Mile 27, near the western edge of the flood plain, and 50 percent passing through the bridges at Mile 36–37 to approximately 5 percent passing through the bridges at Mile 27 and 95 percent through the bridges at Mile 36–37 during average flow periods.The U.S. Geological Survey’s Multi-Dimensional Surface-Water Modeling System was used to simulate water-surface elevation and velocity, and to compute bed shear stress at two areas where the Copper River is affecting the Copper River Highway. After calibration, the model was used to examine the

Congenital blindness limits allocentric to egocentric switching ability.

Science.gov (United States)

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

Directory of Open Access Journals (Sweden)

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.

Science.gov (United States)

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....

River basin administration

Science.gov (United States)

Management of international rivers and their basins is the focus of the Centre for Comparative Studies on (International) River Basin Administration, recently established at Delft University of Technology in the Netherlands. Water pollution, sludge, and conflicting interests in the use of water in upstream and downstream parts of a river basin will be addressed by studying groundwater and consumption of water in the whole catchment area of a river.Important aspects of river management are administrative and policy aspects. The Centre will focus on policy, law, planning, and organization, including transboundary cooperation, posing standards, integrated environmental planning on regional scale and environmental impact assessments.

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

Directory of Open Access Journals (Sweden)

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.

Trends in the occurrence of human and veterinary antibiotics in the sediments of the Yellow River, Hai River and Liao River in northern China

Energy Technology Data Exchange (ETDEWEB)

Lijun, Zhou [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Ying Guangguo, E-mail: guang-guo.ying@gig.ac.cn [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Jianliang, Zhao [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Jifeng, Yang [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Chemistry and Chemical Engineering Department, Hunan University of Arts and Science, Changde 415000 (China); Li, Wang; Bin, Yang; Shan, Liu [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

2011-07-15

The occurrence of four classes of 17 commonly used antibiotics (including fluoroquinolones, tetracycline, sulfonamides, and macrolides) was investigated in the sediments of the Yellow River, Hai River and Liao River in northern China by using rapid resolution liquid chromatography-tandem mass spectrometry. Higher concentrations were detected for most antibiotics in the sediments of the Hai River than in the sediments of the other rivers. Norfloxacin, ofloxacin, ciprofloxacin and oxytetracycline in the three rivers were most frequently detected with concentrations up to 5770, 1290, 653 and 652 ng/g, respectively. High frequencies and concentrations of the detected antibiotics were often found in the downstream of large cities and areas influenced by feedlot and fish ponds. Good fitted linear regression equations between antibiotic concentration and sediment physicochemical properties (TOC, texture and pH) were also found, indicating that sediment properties are important factors influencing the distribution of antibiotics in the sediment of rivers. - Highlights: > Presence of four classes of commonly used antibiotics in the river sediments. > Higher concentrations in the Hai River than in the Liao River and Yellow River. > Norfloxacin, ofloxacin, ciprofloxacin and oxytetracycline most frequently detected. > High antibiotic concentrations often found in the downstream of large cities. > River sediments are an important reservoir of antibiotics. - Higher concentrations of selected antibiotics were determined in the sediments of the Hai River than in the Liao River and Yellow River.

River engineering

NARCIS (Netherlands)

De Vries, M.

1993-01-01

One dimension models - basic eauations, analytical models, numberical models. One dimensional models -suspended load, roughness and resistance of river beds. Solving river problems - tools, flood mitigation, bank protection.

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

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.

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...

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 ...

Trace elements and radionuclides in the Connecticut River and Amazon River estuary

International Nuclear Information System (INIS)

Dion, E.P.

1983-01-01

The Connecticut River, its estuary, and the Amazon River estuary were studied to elucidate some of the processes which control river water chemistry and the flux of elements to the sea. The approach taken was to identify inputs to the Connecticut River and to investigate geochemical processes which modify the dissolved load. The form and quantity of nuclides which are in turn supplied to the estuary are altered by processes unique to that transition zone to the ocean. The Connecticut River estuary was sampled on a seasonal basis to investigate the role of the estuary in controlling the flux of elements to the sea. The knowledge gained from the Connecticut River study was applied to the quantitatively more significant Amazon River estuary. There a variety of samples were analyzed to understand the processes controlling the single greatest flux of elements to the Atlantic Ocean. The results indicate that estimates of the total flux of nuclides to the oceans can best be calculated based on groundwater inputs. Unless significant repositories for nuclides exist in the river-estuarine system, the groundwater flux of dissolved nuclides is that which will eventually be delivered to the ocean despite the reactions which were shown to occur in both rivers and estuaries. 153 references, 63 figures, 28 tables

Contribution of River Mouth Reach to Sediment Load of the Yangtze River

Directory of Open Access Journals (Sweden)

C. Wang

2015-01-01

Full Text Available This paper examined the sediment gain and loss in the river mouth reach of the Yangtze River by considering sediment load from the local tributaries, erosion/accretion of the river course, impacts of sand mining, and water extraction. A quantitative estimation of the contribution of the river mouth reach to the sediment load of the Yangtze River was conducted before and after impoundment of the Three Gorges Dam (TGD in 2003. The results showed that a net sediment load loss of 1.78 million ton/yr (Mt/yr occurred from 1965 to 2002 in the study area. The contribution of this reach to the sediment discharge into the sea is not as high as what was expected before the TGD. With impoundment of the TGD, channel deposition (29.90 Mt/yr and a net sediment loss of 30.89 Mt/yr occurred in the river mouth reach from 2003 to 2012. The river mouth reach has acted as a sink but not a source of sediment since impoundment of the TGD, which has exacerbated the decrease in sediment load. Technologies should be advanced to measure changes in river channel morphology, as well as in water and sediment discharges at the river mouth reach.

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,

Trends in the occurrence of human and veterinary antibiotics in the sediments of the Yellow River, Hai River and Liao River in northern China

International Nuclear Information System (INIS)

Zhou Lijun; Ying Guangguo; Zhao Jianliang; Yang Jifeng; Wang Li; Yang Bin; Liu Shan

2011-01-01

The occurrence of four classes of 17 commonly used antibiotics (including fluoroquinolones, tetracycline, sulfonamides, and macrolides) was investigated in the sediments of the Yellow River, Hai River and Liao River in northern China by using rapid resolution liquid chromatography-tandem mass spectrometry. Higher concentrations were detected for most antibiotics in the sediments of the Hai River than in the sediments of the other rivers. Norfloxacin, ofloxacin, ciprofloxacin and oxytetracycline in the three rivers were most frequently detected with concentrations up to 5770, 1290, 653 and 652 ng/g, respectively. High frequencies and concentrations of the detected antibiotics were often found in the downstream of large cities and areas influenced by feedlot and fish ponds. Good fitted linear regression equations between antibiotic concentration and sediment physicochemical properties (TOC, texture and pH) were also found, indicating that sediment properties are important factors influencing the distribution of antibiotics in the sediment of rivers. - Highlights: → Presence of four classes of commonly used antibiotics in the river sediments. → Higher concentrations in the Hai River than in the Liao River and Yellow River. → Norfloxacin, ofloxacin, ciprofloxacin and oxytetracycline most frequently detected. → High antibiotic concentrations often found in the downstream of large cities. → River sediments are an important reservoir of antibiotics. - Higher concentrations of selected antibiotics were determined in the sediments of the Hai River than in the Liao River and Yellow River.

Charles River

Science.gov (United States)

Information on the efforts of the US EPA, the Commonwealth of Massachusetts, the municipalities within the Charles River Watershed and nongovernmental organizations to improve the water quality of the Charles River.

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

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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

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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.

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...

River and Reservoir Operations Model, Truckee River basin, California and Nevada, 1998

Science.gov (United States)

Berris, Steven N.; Hess, Glen W.; Bohman, Larry R.

2001-01-01

The demand for all uses of water in the Truckee River Basin, California and Nevada, commonly is greater than can be supplied. Storage reservoirs in the system have a maximum effective total capacity equivalent to less than two years of average river flows, so longer-term droughts can result in substantial water-supply shortages for irrigation and municipal users and may stress fish and wildlife ecosystems. Title II of Public Law (P.L.) 101-618, the Truckee?Carson?Pyramid Lake Water Rights Settlement Act of 1990, provides a foundation for negotiating and developing operating criteria, known as the Truckee River Operating Agreement (TROA), to balance interstate and interbasin allocation of water rights among the many interests competing for water from the Truckee River. In addition to TROA, the Truckee River Water Quality Settlement Agreement (WQSA), signed in 1996, provides for acquisition of water rights to resolve water-quality problems during low flows along the Truckee River in Nevada. Efficient execution of many of the planning, management, or environmental assessment requirements of TROA and WQSA will require detailed water-resources data coupled with sound analytical tools. Analytical modeling tools constructed and evaluated with such data could help assess effects of alternative operational scenarios related to reservoir and river operations, water-rights transfers, and changes in irrigation practices. The Truckee?Carson Program of the U.S. Geological Survey, to support U.S. Department of the Interior implementation of P.L. 101-618, is developing a modeling system to support efficient water-resources planning, management, and allocation. The daily operations model documented herein is a part of the modeling system that includes a database management program, a graphical user interface program, and a program with modules that simulate river/reservoir operations and a variety of hydrologic processes. The operations module is capable of simulating lake

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...

Hydrogeological investigations of river bed clogging at a river bank filtration site along the River Warta, Poland

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Przybyłek Jan

2017-12-01

Full Text Available River bank filtration (RBF is a system that enriches groundwater resources by induced infiltration of river water to an aquifer. Problematic during operation of RBF systems is the deterioration of infiltration effectiveness caused by river bed clogging. This situation was observed in the Krajkowo well field which supplies fresh water to the city of Poznań (Poland during and after the long hydrological drought between the years 1989 and 1992. The present note discusses results of specific hydrogeological research which included drilling of a net of boreholes to a depth of 10 m below river bottom (for sediment sampling as well as for hydrogeological measurements, analyses of grain size distribution and relative density studies. The results obtained have allowed the recognition of the origin of the clogging processes, as well as the documentation of the clogged parts of the river bottom designated for unclogging activities.

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

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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.

Science.gov (United States)

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.

Science.gov (United States)

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.

Investing in river health.

Science.gov (United States)

Bennett, J

2002-01-01

Rivers provide society with numerous returns. These relate to both the passive and extractive uses of the resources embodied in river environments. Some returns are manifest in the form of financial gains whilst others are non-monetary. For instance, rivers are a source of monetary income for those who harvest their fish. The water flowing in rivers is extracted for drinking and to water crops and livestock that in turn yield monetary profits. However, rivers are also the source of non-monetary values arising from biological diversity. People who use them for recreation (picnicking, swimming, boating) also receive non-monetary returns. The use of rivers to yield these returns has had negative consequences. With extraction for financial return has come diminished water quantity and quality. The result has been a diminished capacity of rivers to yield (non-extractive) environmental returns and to continue to provide extractive values. A river is like any other asset. With use, the value of an asset depreciates because its productivity declines. In order to maintain the productive capacity of their assets, managers put aside from their profits depreciation reserves that can be invested in the repair or replacement of those assets. Society now faces a situation in which its river assets have depreciated in terms of their capacity to provide monetary and non-monetary returns. An investment in river "repair" is required. But, investment means that society gives up something now in order to achieve some benefit in the future. Society thus has to grapple wih the choice between investing in river health and other investments--such as in hospitals, schools, defence etc. - as well as between investing in river health and current consumption--such as on clothes, food, cars etc. A commonly used aid for investment decision making in the public sector is benefit cost analysis. However, its usefulness in tackling the river investment problem is restricted because it requires all

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.

Science.gov (United States)

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

OpenAIRE

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

2012-01-01

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...

Smartphone based face recognition tool for the blind.

Science.gov (United States)

Kramer, K M; Hedin, D S; Rolkosky, D J

2010-01-01

The inability to identify people during group meetings is a disadvantage for blind people in many professional and educational situations. To explore the efficacy of face recognition using smartphones in these settings, we have prototyped and tested a face recognition tool for blind users. The tool utilizes Smartphone technology in conjunction with a wireless network to provide audio feedback of the people in front of the blind user. Testing indicated that the face recognition technology can tolerate up to a 40 degree angle between the direction a person is looking and the camera's axis and a 96% success rate with no false positives. Future work will be done to further develop the technology for local face recognition on the smartphone in addition to remote server based face recognition.

Flowing with Rivers

Science.gov (United States)

Anderson, Heather

2004-01-01

This article describes a lesson in which students compare how artists have depicted rivers in paintings, using different styles, compositions, subject matter, colors, and techniques. They create a watercolor landscape that includes a river. Students can learn about rivers by studying them on site, through environmental study, and through works of…

Causes of Adult Blindness at Ecwa Eye Hospital, Kano

African Journals Online (AJOL)

user

accounting for 94 (42.3%), 28 (12.6%) and 19 (8.7%) of the unilaterally blind cases. Conclusion: Avoidable causes of blindness were predominant at. ECWA Eye Hospital, Kano. Concerted efforts at increasing cataract surgical volume, awareness and early treatment of glaucoma as well as education on prevention and early.

Rubella Deaf-Blind Child: Implications of Psychological Assessment. Proceedings.

Science.gov (United States)

Rouin, Carole

Presented are proceedings of a conference involving authorities in testing and evaluating the blind, deaf, and deaf-blind. In a paper titled "Psychological Implications of Assessing the Deaf", C. Goetzinger discusses references used in audiology, anatomy and physiology of the ear, degrees of hearing impairment, and implications of the various…

Development of river flood model in lower reach of urbanized river basin

Science.gov (United States)

Yoshimura, Kouhei; Tajima, Yoshimitsu; Sanuki, Hiroshi; Shibuo, Yoshihiro; Sato, Shinji; Lee, SungAe; Furumai, Hiroaki; Koike, Toshio

2014-05-01

Japan, with its natural mountainous landscape, has demographic feature that population is concentrated in lower reach of elevation close to the coast, and therefore flood damage with large socio-economic value tends to occur in low-lying region. Modeling of river flood in such low-lying urbanized river basin is complex due to the following reasons. In upstream it has been experienced urbanization, which changed land covers from natural forest or agricultural fields to residential or industrial area. Hence rate of infiltration and runoff are quite different from natural hydrological settings. In downstream, paved covers and construct of sewerage system in urbanized areas affect direct discharges and it enhances higher and faster flood peak arrival. Also tidal effect from river mouth strongly affects water levels in rivers, which must be taken into account. We develop an integrated river flood model in lower reach of urbanized areas to be able to address above described complex feature, by integrating model components: LSM coupled distributed hydrological model that models anthropogenic influence on river discharges to downstream; urban hydrological model that simulates run off response in urbanized areas; Saint Venant's equation approximated river model that integrates upstream and urban hydrological models with considering tidal effect from downstream. These features are integrated in a common modeling framework so that model interaction can be directly performed. The model is applied to the Tsurumi river basin, urbanized low-lying river basin in Yokohama and model results show that it can simulate water levels in rivers with acceptable model errors. Furthermore the model is able to install miscellaneous water planning constructs, such as runoff reduction pond in urbanized area, flood control field along the river channel, levee, etc. This can be a useful tool to investigate cost performance of hypothetical water management plan against impact of climate change in

Assessment of River Habitat Quality in the Hai River Basin, Northern China

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Yuekui Ding

2015-09-01

Full Text Available We applied a river habitat quality (RHQ assessment method to the Hai River Basin (HRB; an important economic centre in China; to obtain baseline information for water quality improvement; river rehabilitation; and watershed management. The results of the assessment showed that the river habitat in the HRB is seriously degraded. Specifically; 42.41% of the sites; accounting for a river length of 3.31 × 104 km; were designated poor and bad. Habitat in the plain areas is seriously deteriorated; and nearly 50% of the sites; accounting for a river length of 1.65 × 104 km; had either poor or bad habitats. River habitat degradation was attributable to the limited width of the riparian zone (≤5 m; lower coverage of riparian vegetation (≤40%; artificial land use patterns (public and industrial land; frequent occurrence of farming on the river banks and high volumes of solid waste (nearly 10 m3; single flow channels; and rare aquatic plants (≤1 category. At the regional scale; intensive artificial land use types caused by urbanization had a significant impact on the RHQ in the HRB. RHQ was significantly and negatively correlated with farmland (r = 1.000; p < 0.01 and urban land (r = 0.998; p < 0.05; and was significantly and positively correlated with grassland and woodland (r = 1.000; p < 0.01. Intensive artificial land use; created through urbanization processes; has led to a loss of the riparian zone and its native vegetation; and has disrupted the lateral connectivity of the rivers. The degradation of the already essentially black rivers is exacerbated by poor longitudinal connectivity (index of connectivity is 2.08–16.56; caused by reservoirs and sluices. For river habitat rehabilitation to be successful; land use patterns need to be changed and reservoirs and sluices will have to be regulated.

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

Directory of Open Access Journals (Sweden)

Arie Y Nemet

2009-07-01

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

Crossmodal recruitment of the ventral visual stream in congenital blindness

DEFF Research Database (Denmark)

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

2012-01-01

We used functional MRI (fMRI) to test the hypothesis that blind subjects recruit the ventral visual stream during nonhaptic tactile-form recognition. Congenitally blind and blindfolded sighted control subjects were scanned after they had been trained during four consecutive days to perform......, 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...

78 FR 41689 - Safety Zone; Skagit River Bridge, Skagit River, Mount Vernon, WA

Science.gov (United States)

2013-07-11

... submerged automobiles and floating bridge debris in the Skagit River. Following the initial response and...-AA00 Safety Zone; Skagit River Bridge, Skagit River, Mount Vernon, WA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a safety zone around the Skagit River Bridge...

Hydrological River Drought Analysis (Case Study: Lake Urmia Basin Rivers

Directory of Open Access Journals (Sweden)

Mohammad Nazeri Tahrudi

2017-02-01

Full Text Available Introduction: Drought from the hydrological viewpoint is a continuation of the meteorological drought that cause of the lack of surface water such as rivers, lakes, reservoirs and groundwater resources. This analysis, which is generally on the surface streams, reservoirs, lakes and groundwater, takes place as hydrological drought considered and studied. So the data on the quantity of flow of the rivers in this study is of fundamental importance. This data are included, level, flow, river flow is no term (5. Overall the hydrological drought studies are focused on annual discharges, maximum annual discharge or minimum discharge period. The most importance of this analysis is periodically during the course of the analysis remains a certain threshold and subthresholdrunoff volume fraction has created. In situations where water for irrigation or water of a river without any reservoir, is not adequate, the minimum flow analysis, the most important factor to be considered (4. The aim of this study is evaluatingthe statistical distributions of drought volume rivers data from the Urmia Lake’s rivers and its return period. Materials and Methods: Urmia Lake is a biggest and saltiest continued lake in Iran. The Lake Urmia basin is one of the most important basins in Iran region which is located in the North West of Iran. With an extent of 52700 square kilometers and an area equivalent to 3.21% of the total area of the country, This basin is located between the circuit of 35 degrees 40 minutes to 38 degrees 29 minutes north latitude and the meridian of 44 degrees 13 minutes to 47 degrees 53 minutes east longitude. In this study used the daily discharge data (m3s-1 of Urmia Lake Rivers. Extraction of river drought volume The drought durations were extracted from the daily discharge of 13 studied stations. The first mean year was calculated for each 365 days using the Eq 1 (14. (1 (For i=1,2,3,…,365 That Ki is aith mean year, Yijis ith day discharge in jth

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

OpenAIRE

Katja Gutschke; Aglaja Stirn; Erich Kasten

2017-01-01

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 wi...

75 FR 51945 - Safety Zone; Potomac River, St. Mary's River, St. Inigoes, MD

Science.gov (United States)

2010-08-24

...-AA00 Safety Zone; Potomac River, St. Mary's River, St. Inigoes, MD AGENCY: Coast Guard, DHS. ACTION... of the St. Mary's River, a tributary of the Potomac River. This action is necessary to provide for.... Navy helicopter located near St. Inigoes, Maryland. This safety zone is intended to protect the...

AODA Training Experiences of Blindness and Visual Impairment Professionals

Science.gov (United States)

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

2009-01-01

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

Short term memory and working memory in blind versus sighted children.

Science.gov (United States)

Withagen, Ans; Kappers, Astrid M L; Vervloed, Mathijs P J; Knoors, Harry; Verhoeven, Ludo

2013-07-01

There is evidence that blind people may strengthen their memory skills to compensate for absence of vision. However, which aspects of memory are involved is open to debate and a developmental perspective is generally lacking. In the present study, we compared the short term memory (STM) and working memory (WM) of 10-year-old blind children and sighted children. STM was measured using digit span forward, name learning, and word span tasks; WM was measured using listening span and digit span backward tasks. The blind children outperformed their sighted peers on both STM and WM tasks. The enhanced capacity of the blind children on digit span and other STM tasks confirms the results of earlier research; the significantly better performance of the blind children relative to their sighted peers on verbal WM tasks is a new interesting finding. Task characteristics, including the verbal nature of the WM tasks and strategies used to perform these tasks, are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Driven-Walking for Visually Impaired/Blind People through WiMAX

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Panagiotis GIOANNIS

2010-03-01

Full Text Available It is known that people who are blind/visually impaired find it difficult to move, especially in unknown places. Usually the only help they have is their walking stick (white cane, a guide dog and sometimes special warning sounds or road signals at specific positions. Material and Method: In this paper we are trying to find a solution on how to build an appropriate navigating system for blind people. Results: Based on benefits of powerful properties of mobile WiMAX standard we suggest an important navigate application which can translate a digital visual environment properly for blind/visually impaired users through a plethora of combinations such as voice, brain or tongue signals. Conclusions: We believe that such an idea will be an initial point for a plethora of applications which will eliminate walking disabilities of blind/visually people.

Effects of thermal treatment on the MgxZn1−xO films and fabrication of visible-blind and solar-blind ultraviolet photodetectors

International Nuclear Information System (INIS)

Tian, Chunguang; Jiang, Dayong; Tan, Zhendong; Duan, Qian; Liu, Rusheng; Sun, Long; Qin, Jieming; Hou, Jianhua; Gao, Shang; Liang, Qingcheng; Zhao, Jianxun

2014-01-01

Highlights: • Single-phase wurtzite/cubic Mg x Zn 1−x O films were grown by RF magnetron sputtering technique. • We focus on the red-shift caused by annealing the Mg x Zn 1−x O films. • MSM-structured visible-blind and solar-blind UV photodetectors were fabricated. - Abstract: A series of single-phase Mg x Zn 1−x O films with different Mg contents were prepared on quartz substrates by RF magnetron sputtering technique using different MgZnO targets, and annealed under the atmospheric environment. The absorption edges of Mg x Zn 1−x O films can cover the whole near ultraviolet and even the whole solar-blind spectra range, and the solar-blind wurtzite/cubic Mg x Zn 1−x O films have been realized successfully by the same method. In addition, the absorption edges of annealed films shift to a long wavelength, which is caused by the diffusion of Zn atoms gathering at the surface during the thermal treatment process. Finally, the truly solar-blind metal-semiconductor-metal structured photodetectors based on wurtzite Mg 0.445 Zn 0.555 O and cubic Mg 0.728 Zn 0.272 O films were fabricated. The corresponding peak responsivities are 17 mA/W at 275 nm and 0.53 mA/W at 250 nm under a 120 V bias, respectively

The impact of exercise therapy on the musculoskeletal abnormalities of blind boy students of 12- 18 years old at Tehran Mohebbi blind school

Directory of Open Access Journals (Sweden)

Habib Allah Jadidi

2009-08-01

Full Text Available Introduction: The purpose of this study was to examine the 13 musculoskeletal abnormalities (fronthead, lateral bending head, shoulder dropping, scoliosis, kyphosis, lumbar lordosis, flat back,pelvicobliguity, genu varum, x.leg, flat foot, pes cavus, and hallux valgus after a period of exercisetherapy on the blind boy students without secondary disability.Materials and Methods: In this semi-experimental research, 60 boy students were included fromsecondary and high school (12-18 years old including 34 congenital blind and 26 semi blind. Theywere selected among 135 students at Tehran Mohebbi blind school. They were tested by measurementtools (symetrigraph, antropometer, and podioscope. After examining the results by the New York test,the students who were diagnosed with one or more musculoskeletal abnormalities took part in fourmonth’sexercises with 3 sessions at weak. The results were registered after the end of the exerciseprogram and administered secondary exam. The data before and after the exam were analyzed.Results: 80 percents of the blind students at pre-exam had musculoskeletal abnormalities which aredecreased to 45 percent after exercises. There were significant differences on the rate of recovery at 11abnormalities (Exact – Sign = 0 < 0/05 and there were not significant differences at pelvicobliguityand x.leg abnormalities (Exact – Sign = 1 < 0/05.Conclusion: the research findings emphasized on the validation and important of exercise therapyon musculoskeletal abnormalities.

Bridging the gap between DeafBlind minds: interactional and social foundations of intention attribution in the Seattle DeafBlind community

OpenAIRE

Edwards, Terra

2015-01-01

This article is concerned with social and interactional processes that simplify pragmatic acts of intention attribution. The empirical focus is a series of interactions among DeafBlind people in Seattle, Washington, where pointing signs are used to individuate objects of reference in the immediate environment. Most members of this community are born deaf and slowly become blind. They come to Seattle using Visual American Sign Language, which has emerged and developed in a field organized arou...

Bridging the Gap Between DeafBlind Minds: interactional and social foundations of intention-attribution in the Seattle DeafBlind community

Directory of Open Access Journals (Sweden)

Terra eEdwards

2015-10-01

Full Text Available This article is concerned with social and interactional processes that simplify pragmatic acts of intention attribution. The empirical focus is a series of interactions among DeafBlind people in Seattle, Washington, where pointing signs are used to individuate objects of reference in the im-mediate environment. Most members of this community are born deaf and slowly become blind. They come to Seattle using Visual American Sign Language, which has emerged and developed in a field organized around visual modes of access. However, as vision deteriorates, links be-tween deictic signs and the present, remembered, or imagined environment erode in idiosyncratic ways across the community of language-users, and it becomes increasingly difficult for partici-pants to converge on objects of reference. In the past, DeafBlind people have addressed this problem by relying on sighted interpreters. Under the influence of the recent pro-tactile movement, they have turned instead to one another to find new solutions to their referential prob-lems. Drawing on analyses of 120 hours of videorecorded interaction and language-use, detailed fieldnotes collected during twelve months of sustained anthropological fieldwork, and more than 15 years of involvement in this community in a range of capacities, I show how DeafBlind peo-ple are generating new and reciprocal modes of access to their environment, and how this pro-cess is aligning language with context in novel ways. I propose two mechanisms that can account for this process: deictic integration and embedding in the social field. I argue that together, these interactional and social mechanisms yield a deictic system set to retrieve a restricted range of values from the extra-linguistic context, thereby attenuating the cognitive demands of intention-attribution and narrowing the gap between DeafBlind minds.

Impact of a sight-saver clinic on the prevalence of blindness in ...

African Journals Online (AJOL)

solely to age-related cataract was 0,39% (95% Cl ... The prevalence of blindness due solely to age- related ... National Council for the Blind, to provide preventive and ... of the optic disc and macula with a direct ophthalmoscope. ... whose cataracts had been treated by surgery were included .... Blindness and eye disease in.

Denitrification in the Mississippi River network controlled by flow through river bedforms

Science.gov (United States)

Gomez-Velez, Jesus D.; Harvey, Judson W.; Cardenas, M. Bayani; Kiel, Brian

2015-01-01

Increasing nitrogen concentrations in the world’s major rivers have led to over-fertilization of sensitive downstream waters1, 2, 3, 4. Flow through channel bed and bank sediments acts to remove riverine nitrogen through microbe-mediated denitrification reactions5, 6, 7, 8, 9, 10. However, little is understood about where in the channel network this biophysical process is most efficient, why certain channels are more effective nitrogen reactors, and how management practices can enhance the removal of nitrogen in regions where water circulates through sediment and mixes with groundwater - hyporheic zones8, 11, 12. Here we present numerical simulations of hyporheic flow and denitrification throughout the Mississippi River network using a hydrogeomorphic model. We find that vertical exchange with sediments beneath the riverbed in hyporheic zones, driven by submerged bedforms, has denitrification potential that far exceeds lateral hyporheic exchange with sediments alongside river channels, driven by river bars and meandering banks. We propose that geomorphic differences along river corridors can explain why denitrification efficiency varies between basins in the Mississippi River network. Our findings suggest that promoting the development of permeable bedforms at the streambed - and thus vertical hyporheic exchange - would be more effective at enhancing river denitrification in large river basins than promoting lateral exchange through induced channel meandering. 

Prevalence of blindness and diabetic retinopathy in northern Jordan.

Science.gov (United States)

Rabiu, Mansur M; Al Bdour, Muawyah D; Abu Ameerh, Mohammed A; Jadoon, Muhammed Z

2015-01-01

To estimate the prevalence of blindness, visual impairment, diabetes, and diabetic retinopathy in north Jordan (Irbid) using the rapid assessment of avoidable blindness and diabetic retinopathy methodology. A multistage cluster random sampling technique was used to select participants for this survey. A total of 108 clusters were selected using probability proportional to size method while subjects within the clusters were selected using compact segment method. Survey teams moved from house to house in selected segments examining residents 50 years and older until 35 participants were recruited. All eligible people underwent a standardized examination protocol, which included ophthalmic examination and random blood sugar test using digital glucometers (Accu-Chek) in their homes. Diabetic retinopathy among diabetic patients was assessed through dilated fundus examination. A total of 3638 out of the 3780 eligible participants were examined. Age- and sex-adjusted prevalence of blindness, severe visual impairment, and visual impairment with available correction were 1.33% (95% confidence interval [CI] 0.87-1.73), 1.82% (95% CI 1.35-2.25), and 9.49% (95% CI 8.26-10.74), respectively, all higher in women. Untreated cataract and diabetic retinopathy were the major causes of blindness, accounting for 46.7% and 33.2% of total blindness cases, respectively. Glaucoma was the third major cause, accounting for 8.9% of cases. The prevalence of diabetes mellitus was 28.6% (95% CI 26.9-30.3) among the study population and higher in women. The prevalence of any retinopathy among diabetic patients was 48.4%. Cataract and diabetic retinopathy are the 2 major causes of blindness and visual impairment in northern Jordan. For both conditions, women are primarily affected, suggesting possible limitations to access to services. A diabetic retinopathy screening program needs to proactively create sex-sensitive awareness and provide easily accessible screening services with prompt treatment.

A rapid assessment of avoidable blindness in Southern Zambia.

Directory of Open Access Journals (Sweden)

Robert Lindfield

Full Text Available INTRODUCTION: A rapid assessment of avoidable blindness (RAAB was conducted in Southern Zambia to establish the prevalence and causes of blindness in order to plan effective services and advocate for support for eye care to achieve the goals of VISION 2020: the right to sight. METHODS: Cluster randomisation was used to select villages in the survey area. These were further subdivided into segments. One segment was selected randomly and a survey team moved from house to house examining everyone over the age of 50 years. Each individual received a visual acuity assessment and simple ocular examination. Data was recorded on a standard proforma and entered into an established software programme for analysis. RESULTS: 2.29% of people over the age of 50 were found to be blind (VA <3/60 in the better eye with available correction. The major cause of blindness was cataract (47.2% with posterior segment disease being the next main cause (18.8%. 113 eyes had received cataract surgery with 30.1% having a poor outcome (VA <6/60 following surgery. Cataract surgical coverage showed that men (72% received more surgery than women (65%. DISCUSSION: The results from the RAAB survey in Zambia were very similar to the results from a similar survey in Malawi, where the main cause of blindness was cataract but posterior segment disease was also a significant contributor. Blindness in this part of Zambia is mainly avoidable and there is a need for comprehensive eye care services that can address both cataract and posterior segment disease in the population if the aim of VISION 2020 is to be achieved. Services should focus on quality and gender equity of cataract surgery.

Health-related quality of life following blind rehabilitation.

Science.gov (United States)

Kuyk, Thomas; Liu, Lei; Elliott, Jeffry L; Grubbs, Hartley E; Owsley, Cynthia; McGwin, Gerald; Griffin, Russell L; Fuhr, Patti S

2008-05-01

The purpose of this study was to investigate the effect of residential blind rehabilitation on patients' vision-targeted health-related quality of life (HRQOL) and general physical and mental function. The National Eye Institute 25-item Visual Function Questionnaire (NEI VFQ) plus appendix questions, the 12-item Short-Form Health Survey (SF-12), Hope Scale and Coopersmith self-esteem inventory were administered to 206 legally blind veterans prior to their entering a residential (in-patient) blind rehabilitation program and again to 185 and 176 of the original cohort at 2 and 6 months after completion of the rehabilitation program, respectively. Data on visual acuity, visual field extent, contrast sensitivity and scanning ability were also collected. The duration of the in-patient rehabilitation programs ranged from 11 to 109 days. Questionnaire scores were compared pre-rehabilitation and post-rehabilitation. Following rehabilitation there was a significant improvement in nine of 11 NEI VFQ subscales and in a composite score at both the 2- and 6-month post-rehabilitation intervals. Mental health (SF-12) and self esteem also improved significantly although physical health ratings declined over the course of the study (approximately 10 months). Residential blind rehabilitation appears to improve patients' self-reported vision-targeted HRQOL, self-esteem and mental health aspects of generic HRQOL.

Blind spots for neutralino dark matter in the NMSSM

Energy Technology Data Exchange (ETDEWEB)

Badziak, Marcin; Olechowski, Marek; Szczerbiak, Paweł [Institute of Theoretical Physics, Faculty of Physics, University of Warsaw,ul. Pasteura 5, PL-02-093 Warsaw (Poland)

2016-03-25

Spin-independent cross-section for neutralino dark matter scattering off nuclei is investigated in the NMSSM. Several classes of blind spots for direct detection of singlino-Higgsino dark matter are analytically identified, including such that have no analog in the MSSM. It is shown that mixing of the Higgs doublets with the scalar singlet has a big impact on the position of blind spots in the parameter space. In particular, this mixing allows for more freedom in the sign assignment for the parameters entering the neutralino mass matrix, required for a blind spot to occur, as compared to the MSSM or the NMSSM with decoupled singlet. Moreover, blind spots may occur for any composition of a singlino-Higgsino LSP. Particular attention is paid to cases with the singlet-dominated scalar lighter than the 125 GeV Higgs for which a vanishing tree-level spin-independent scattering cross-section may result from destructive interference between the Higgs and the singlet-dominated scalar exchange. Correlations of the spin-independent scattering cross-section with the Higgs observables are also discussed.

Blind spots for neutralino dark matter in the NMSSM

International Nuclear Information System (INIS)

Badziak, Marcin; Olechowski, Marek; Szczerbiak, Paweł

2016-01-01

Spin-independent cross-section for neutralino dark matter scattering off nuclei is investigated in the NMSSM. Several classes of blind spots for direct detection of singlino-Higgsino dark matter are analytically identified, including such that have no analog in the MSSM. It is shown that mixing of the Higgs doublets with the scalar singlet has a big impact on the position of blind spots in the parameter space. In particular, this mixing allows for more freedom in the sign assignment for the parameters entering the neutralino mass matrix, required for a blind spot to occur, as compared to the MSSM or the NMSSM with decoupled singlet. Moreover, blind spots may occur for any composition of a singlino-Higgsino LSP. Particular attention is paid to cases with the singlet-dominated scalar lighter than the 125 GeV Higgs for which a vanishing tree-level spin-independent scattering cross-section may result from destructive interference between the Higgs and the singlet-dominated scalar exchange. Correlations of the spin-independent scattering cross-section with the Higgs observables are also discussed.

Navigation with a sensory substitution device in congenitally blind individuals

DEFF Research Database (Denmark)

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

2011-01-01

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

A Literature Review of Inattentional and Change Blindness in Transportation

Science.gov (United States)

2009-12-01

Inattentional blindness refers to situations in which a person is unaware of a change that is occurring because attention is not currently focused on what is changing. Change blindness occurs when a change takes place during an eye movement or blink ...

Prevalence and Determinants of Corneal Blindness in a Semi-Urban ...

African Journals Online (AJOL)

2017-07-26

Jul 26, 2017 ... blindness with a prevalence of 1.1% (95% confidence interval: 0.5–1.7). Corneal blindness .... Power Holding Company of Nigeria. The local ... trauma, the redness of the eye with or without pain, history suggestive of measles,.

Building a future full of opportunity for blind youths in science

Science.gov (United States)

Beck-Winchatz, B.; Riccobono, M. A.

Like their sighted peers many blind students in elementary middle and high school are naturally interested in space This interest can motivate them to learn fundamental scientific quantitative and critical thinking skills and sometimes even lead to careers in SMET disciplines However these students are often at a disadvantage in science because of the ubiquity of important graphical information that is generally not available in accessible formats the unfamiliarity of teachers with non-visual teaching methods lack of access to blind role models and the low expectations of their teachers and parents In this presentation we will describe joint efforts by NASA and the National Federation of the Blind s NFB Center for Blind Youth in Science to develop and implement strategies to promote opportunities for blind youth in science These include the development of tactile space science books and curriculum materials science academies for blind middle school and high school students internship and mentoring programs as well as research on non-visual learning techniques This partnership with the NFB exemplifies the effectiveness of collaborations between NASA and consumer-directed organizations to improve opportunities for underserved and underrepresented individuals Session participants will also have the opportunity to examine some of the recently developed tactile space science education materials themselves

78 FR 28492 - Special Local Regulation; Low Country Splash, Wando River, Cooper River, and Charleston Harbor...

Science.gov (United States)

2013-05-15

...-AA08 Special Local Regulation; Low Country Splash, Wando River, Cooper River, and Charleston Harbor... establishing a special local regulation on the waters of the Wando River, Cooper River, and Charleston Harbor... rulemaking (NPRM) entitled, ``Special Local Regulation; Low Country Splash, Wando River, Cooper River, and...

Balancing hydropower production and river bed incision in operating a run-of-river hydropower scheme along the River Po

Science.gov (United States)

Denaro, Simona; Dinh, Quang; Bizzi, Simone; Bernardi, Dario; Pavan, Sara; Castelletti, Andrea; Schippa, Leonardo; Soncini-Sessa, Rodolfo

2013-04-01

Water management through dams and reservoirs is worldwide necessary to support key human-related activities ranging from hydropower production to water allocation, and flood risk mitigation. Reservoir operations are commonly planned in order to maximize these objectives. However reservoirs strongly influence river geomorphic processes causing sediment deficit downstream, altering the flow regime, leading, often, to process of river bed incision: for instance the variations of river cross sections over few years can notably affect hydropower production, flood mitigation, water supply strategies and eco-hydrological processes of the freshwater ecosystem. The river Po (a major Italian river) has experienced severe bed incision in the last decades. For this reason infrastructure stability has been negatively affected, and capacity to derive water decreased, navigation, fishing and tourism are suffering economic damages, not to mention the impact on the environment. Our case study analyzes the management of Isola Serafini hydropower plant located on the main Po river course. The plant has a major impact to the geomorphic river processes downstream, affecting sediment supply, connectivity (stopping sediment upstream the dam) and transport capacity (altering the flow regime). Current operation policy aims at maximizing hydropower production neglecting the effects in term of geomorphic processes. A new improved policy should also consider controlling downstream river bed incision. The aim of this research is to find suitable modeling framework to identify an operating policy for Isola Serafini reservoir able to provide an optimal trade-off between these two conflicting objectives: hydropower production and river bed incision downstream. A multi-objective simulation-based optimization framework is adopted. The operating policy is parameterized as a piecewise linear function and the parameters optimized using an interactive response surface approach. Global and local

76 FR 71342 - Proposed CERCLA Administrative Cost Recovery Settlement; River Forest Dry Cleaners Site, River...

Science.gov (United States)

2011-11-17

... Settlement; River Forest Dry Cleaners Site, River Forest, Cook County, IL AGENCY: Environmental Protection... response costs concerning the River Forest Dry Cleaners site in River Forest, Cook County, Illinois with... code: C-14J, Chicago, Illinois 60604. Comments should reference the River Forest Dry Cleaners Site...

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.

Blindness and Glaucoma: A Multicenter Data Review from 7 Academic Eye Clinics.

Directory of Open Access Journals (Sweden)

Luca Rossetti

Full Text Available To evaluate frequency, conversion rate, and risk factors for blindness in glaucoma patients treated in European Universities.This multicenter retrospective study included 2402 consecutive patients with glaucoma in at least one eye. Medical charts were inspected and patients were divided into those blind and the remainder ('controls'. Blindness was defined as visual acuity≤0.05 and/or visual field loss to less than 10°.Unilateral and bilateral blindness were respectively 11.0% and 1.6% at the beginning, and 15.5% and 3.6% at the end of the observation period (7.5±5.5 years, range:1-25 years; conversion to blindness (at least unilateral was 1.1%/year. 134 eyes (97 patients developed blindness by POAG during the study. At the first access to study centre, they had mean deviation (MD of -17.1±8.3 dB and treated intraocular pressure (IOP of 17.1±6.6 mmHg. During follow-up the IOP decreased by 14% in these eyes but MD deteriorated by 1.1±3.5 dB/year, which was 5-fold higher than controls (0.2±1.6 dB/year. In a multivariate model, the best predictors for blindness by glaucoma were initial MD (p<0.001, initial IOP (p<0.001, older age at the beginning of follow-up (p<0.001, whereas final IOP was found to be protective (p<0.05.In this series of patients, blindness occurred in about 20%. Blindness by glaucoma had 2 characteristics: late diagnosis and/or late referral, and progression of the disease despite in most cases IOP was within the range of normality and target IOP was achieved; it could be predicted by high initial MD, high initial IOP, and old age.

Rivers running deep : complex flow and morphology in the Mahakam River, Indonesia

NARCIS (Netherlands)

Vermeulen, B.

2014-01-01

Rivers in tropical regions often challenge our geomorphological understanding of fluvial systems. Hairpin bends, natural scours, bifurcate meander bends, tie channels and embayments in the river bank are a few examples of features ubiquitous in tropical rivers. Existing observation techniques

An Economic Analysis of Color-Blind Affirmative Action

OpenAIRE

Tolga Yuret

2008-01-01

This article offers an economic analysis of color-blind alternatives to conventional affirmative action policies in higher education, focusing on efficiency issues. When the distribution of applicants' traits is fixed (i.e., in the short-run) color blindness leads colleges to shift weight from academic traits that predict performance to social traits that proxy for race. Using data on matriculates at several selective colleges and universities, we estimate that the short-run efficiency cost o...

Concepts and Criteria for Blind Quantum Source Separation

OpenAIRE

Deville, Alain; Deville, Yannick

2016-01-01

Blind Source Separation (BSS) is an active domain of Classical Information Processing. The development of Quantum Information Processing has made possible the appearance of Blind Quantum Source Separation (BQSS). This article discusses some consequences of the existence of the entanglement phenomenon, and of the probabilistic aspect of quantum measurements, upon BQSS solutions. It focuses on a pair of spins initially separately prepared in a pure state, and then with an undesired coupling bet...

Memory distorions resulting from a choice blindness task

OpenAIRE

Pärnamets, Philip; Hall, Lars; Johansson, Petter

2015-01-01

Using a choice blindness paradigm, it is possible to switch decisions and outcomes in simple choice tasks. Such switches have been found to carry over into later choices, hypothesized to be mediated by beliefs about earlier decisions. Here we investigated participants’ memories for stimuli in a simple choice blindness task involving preferential choices between pairs of faces. We probed participants’ recognition and source memory following a round of choices where on some trials participants ...

Superior serial memory in the blind: a case of cognitive compensatory adjustment.

Science.gov (United States)

Raz, Noa; Striem, Ella; Pundak, Golan; Orlov, Tanya; Zohary, Ehud

2007-07-03

In the absence of vision, perception of space is likely to be highly dependent on memory. As previously stated, the blind tend to code spatial information in the form of "route-like" sequential representations [1-3]. Thus, serial memory, indicating the order in which items are encountered, may be especially important for the blind to generate a mental picture of the world. In accordance, we find that the congenitally blind are remarkably superior to sighted peers in serial memory tasks. Specifically, subjects heard a list of 20 words and were instructed to recall the words according to their original order in the list. The blind recalled more words than the sighted (indicating better item memory), but their greatest advantage was in recalling longer word sequences (according to their original order). We further show that the serial memory superiority of the blind is not merely a result of their advantage in item recall per se (as we additionally confirm via a separate recognition memory task). These results suggest the refinement of a specific cognitive ability to compensate for blindness in humans.

Exploring Controls on Sinuousity, Terraces and River Capture in the Upper Dajia River, Taiwan

Science.gov (United States)

Belliveau, L. C.; Ouimet, W. B.; Chan, Y. C.; Byrne, T. B.

2015-12-01

Taiwan is one of the most tectonically active regions in the world and is prone to landslides due to steep topography, large earthquakes and frequent typhoons. Landslides often affect and alter the river valleys beneath them, producing knickpoints on longitudinal river profiles, segmenting valleys into mixed bedrock-alluvial rivers and affecting river incision for tens to thousands of years. This study investigates the origin and evolution of complex channel morphologies, terraces and river capture along a 20km stretch of the Upper Da-Jia River in the Heping area of Taiwan. Through GIS analysis and field studies, we explore controls on river channel sinuousity, terrace development and river capture in relation to tectonic and climatic forcing, rock erodibility and landslides. High channel sinuousity is proposed as the result of a coupling between bank erosion and landslides. We discuss three types of landslide-induced meanders and increased sinuousity: (a) depositional-push meanders, (b) failure-zone erosional meanders, and (c) complex-erosional meanders. We also investigate spatial variation in channel morphology (slope, width) and the distribution and heights of river terraces within the Upper Da-Jia watershed associated with periods of widespread valley filling from landslide activity. Examples of river capture provide further evidence of the dynamic interactions between river incision, landslides and associated changes in channel morphology and terrace development within steep rapidly uplift, eroding and evolving mountain belts.

Blind Grid Scoring Record No. 290

National Research Council Canada - National Science Library

Overbay, Larry; Robitaille, George

2005-01-01

...) utilizing the APG Standardized UXO Technology Demonstration Site Blind Grid. Scoring Records have been coordinated by Larry Overbay and the Standardized UXO Technology Demonstration Site Scoring Committee...

Blind Grid Scoring Record No. 293

National Research Council Canada - National Science Library

Overbay, Larry; Robitaille, George; Archiable, Robert; Fling, Rick; McClung, Christina

2005-01-01

...) utilizing the YPG Standardized UXO Technology Demonstration Site Blind Grid. Scoring Records have been coordinated by Larry Overbay and the Standardized UXO Technology Demonstration Site Scoring Committee...

River restoration - Malaysian/DID perspective

International Nuclear Information System (INIS)

Ahmad Darus

2006-01-01

Initially the river improvement works in Malaysia was weighted on flood control to convey a certain design flood with the lined and channelized rivers. But in late 2003 did has makes the approaches that conservation and improvement of natural function of river, i.e. river environment and eco-system should be incorporated inside the planning and design process. Generally, river restoration will focus on four approaches that will improve water quality, which is improving the quality of stormwater entering the river, maximizing the quantity of the urban river riparian corridor, stabilizing the riverbank, and improving the habitat within the river. This paper outlined the appropriate method of enhancing impairment of water quality from human activities effluent and others effluent. (Author)

Bed Degradation and Sediment Export from the Missouri River after Dam Construction and River Training: Significance to Lower Mississippi River Sediment Loads

Science.gov (United States)

Blum, M. D.; Viparelli, E.; Sulaiman, Z. A.; Pettit, B. S.

2016-12-01

More than 40,000 dams have been constructed in the Mississippi River drainage basin, which has had a dramatic impact on suspended sediment load for the Mississippi delta. The most significant dams were constructed in the 1950s on the Missouri River in South Dakota, after which total suspended loads for the lower Mississippi River, some 2500 km downstream, were cut in half: gauging station data from the Missouri-Mississippi system show significant load reductions immediately after dam closure, followed by a continued downward trend since that time. The delta region is experiencing tremendous land loss in response to acceleration of global sea-level rise, and load reductions of this magnitude may place severe limits on mitigation efforts. Here we examine sediment export from the Missouri system due to bed scour. The US Army Corps of Engineers has compiled changes in river stage at constant discharge for 8 stations between the lowermost dam at Yankton, South Dakota and the Missouri-Mississippi confluence at St. Louis (a distance of 1250 river km), for the period 1930-2010, which we have updated to 2015. These data show two general reaches of significant bed degradation. The first extends from the last major dam at Yankton, South Dakota downstream 300 km to Omaha, Nebraska, where degradation in response to the dam exceeds 3 m. The second reach, with >2.5 m of degradation, occurs in and around Kansas City, Missouri, and has been attributed to river training activities. The reach between Omaha and Kansas City, as well as the lower Missouri below Kansas City, show River due to bed scour following dam construction and river training. This number equates to 20-25 million tons per year, which is sufficient to account for 30% of the total Missouri River load, and 15% of the total post-dam annual sediment load for the lower Mississippi River. For perspective, the quantity of sediment exported from the Missouri River due to bed scour is greater than the total load for all

Color-Blindness Study: Color Discrimination on the TICCIT System.

Science.gov (United States)

Asay, Calvin S.; Schneider, Edward W.

The question studied whether the specific seven TICCIT system colors used within color coding schemes can be a source of confusion, or not seen at all, by the color-blind segment of target populations. Subjects were 11 color-blind and three normally sighted students at Brigham Young University. After a preliminary training exercise to acquaint the…

Research Report: Self-Employment for Persons Who Are Blind.

Science.gov (United States)

Moore, J. Elton; Cavenaugh, Brenda S.

2003-01-01

This article discusses self-employment as an employment option for individuals who are blind. Analysis of trends indicates the total number of facility managers who are blind in the Randolph-Sheppard Program declined from 3,524 in 1994 to 2,711 in FY 2001 and that self-employment outcomes typically cost less than competitive outcomes. (Contains…

Integrated river basin management of Južna Morava River

Directory of Open Access Journals (Sweden)

Borisavljević Ana

2012-01-01

Full Text Available In the last decade in particular, Serbia encountered the problems of drinking water supply, which influenced the perception of professional public about the water crisis but also started more intensive work on water resource perseverance as well as the implementation of European Water Directive. One of the main demands of the Directive focuses on integrated river basin management (IRBM, which is a complex and a large task. The need to collect data on water quality and quantity, specific and key issues of water management in Južna Morava river basin, pressures on river ecosystem, flood risks and erosion problems, cross-border issues, socioeconomic processes, agricultural development as well as protected areas, and also to give the measures for solving problems and pressures recognized in the basin, is undisputable. This paper focuses on detailed analysis of specific pressures on river ecosystem and composition of recommendations for integrated management of Južna Morava river basin as cross-border river basin, taking into the account European experiences in IRBM. [Projekat Ministarstva nauke Republike Srbije, br. 43007: Istraživanje klimatskih promena na životnu sredinu - praćenje uticaja, adaptacija i ublažavanje, podprojekat br. 9: Učestalost bujičnih poplava, degradacija zemljišta i voda kao posledica globalnih promena

Self-delivered misinformation - Merging the choice blindness and misinformation effect paradigms.

Science.gov (United States)

Stille, Lotta; Norin, Emelie; Sikström, Sverker

2017-01-01

Choice blindness is the failure to detect a discrepancy between a choice and its outcome. The misinformation effect occurs when the recollection of an event changes because new, misleading information about the event is received. The purpose of this study was to merge the choice blindness and misinformation effect paradigms, and thus examine whether choice blindness can be created for individuals' recollections of a witnessed event, and whether this will affect their later recollections of the event. Thus, as a way of delivering misinformation the participants ostensibly became their own source of the misleading information. The participants watched a short film and filled out a questionnaire about events shown in the film. Some of their answers were then manipulated using reattachable stickers, which allowed alteration of their original answers. The participants gave justifications for their manipulated choices, and later their recollection of the original event was tested through another questionnaire. Choice blindness was created for a majority of the participants. A majority of the choice blind participants later changed their reported recollection of the event in line with the manipulations, whereas only a small minority of the participants in the control condition changed their recollection. This study provides new information about the misinformation effect, suggesting that this effect also can occur when misinformation is given immediately following presentation of the original stimuli, and about choice blindness and its effects on the recollections of events. The results suggest that memory blindness can be created when people inadvertently supply themselves with misleading information about an event, causing a change in their recollection.

Equity and Blindness: Closing Evidence Gaps to Support Universal Eye Health.

Science.gov (United States)

Ramke, Jacqueline; Zwi, Anthony B; Palagyi, Anna; Blignault, Ilse; Gilbert, Clare E

2015-01-01

The World Health Organization Program for the Prevention of Blindness adopted the principles of universal health coverage (UHC) in its latest plan, Universal Eye Health: A Global Action Plan, 2014-2019. This plan builds on the achievements of Vision 2020, which aimed to reduce the global prevalence of avoidable blindness, and its unequal distribution, by the year 2020. We reviewed the literature on health equity and the generation and use of evidence to promote equity, particularly in eye health. We describe the nature and extent of the equity-focused evidence to support and inform eye health programs on the path to universal eye health, and propose ways to improve the collection and reporting of this evidence. Blindness prevalence decreased in all regions of the world between 1990 and 2010, albeit not at the same rate or to the same extent. In 2010, the prevalence of blindness in West Africa (6.0%) remained 15 times higher than in high-income regions (0.4%); within all regions, women had a higher prevalence of blindness than men. Beyond inter-regional and sex differences, there is little comparable data on the distribution of blindness across social groups within regions and countries, or on whether this distribution has changed over time. Similarly, interventions known to address inequity in blindness are few, and equity-relevant goals, targets and indicators for eye health programs are scarce. Equity aims of eye health programs can benefit from the global momentum towards achieving UHC, and the progress being made on collecting, communicating and using equity-focused evidence.

Self-delivered misinformation - Merging the choice blindness and misinformation effect paradigms.

Directory of Open Access Journals (Sweden)

Lotta Stille

Full Text Available Choice blindness is the failure to detect a discrepancy between a choice and its outcome. The misinformation effect occurs when the recollection of an event changes because new, misleading information about the event is received. The purpose of this study was to merge the choice blindness and misinformation effect paradigms, and thus examine whether choice blindness can be created for individuals' recollections of a witnessed event, and whether this will affect their later recollections of the event. Thus, as a way of delivering misinformation the participants ostensibly became their own source of the misleading information. The participants watched a short film and filled out a questionnaire about events shown in the film. Some of their answers were then manipulated using reattachable stickers, which allowed alteration of their original answers. The participants gave justifications for their manipulated choices, and later their recollection of the original event was tested through another questionnaire. Choice blindness was created for a majority of the participants. A majority of the choice blind participants later changed their reported recollection of the event in line with the manipulations, whereas only a small minority of the participants in the control condition changed their recollection. This study provides new information about the misinformation effect, suggesting that this effect also can occur when misinformation is given immediately following presentation of the original stimuli, and about choice blindness and its effects on the recollections of events. The results suggest that memory blindness can be created when people inadvertently supply themselves with misleading information about an event, causing a change in their recollection.

Information Communication Technology to support and include Blind students in a school for all An Interview study of teachers and students’ experiences with inclusion and ICT support to blind students

OpenAIRE

Rony, Mahbubur Rahman

2017-01-01

The topic of this is this study is how blind students and teachers experiences Information Communication Technology as a tool to support and include blind students in a school for all. The study investigates how Information and Communication Technologies (ICT) enables blind students to adjust into non-special schools. The research method used to collect data is interview. The goal is to get insight to teachers and students’ experiences with inclusion and ICT as a tool to support blind student...

78 FR 18277 - Special Local Regulation; Low Country Splash, Wando River, Cooper River, and Charleston Harbor...

Science.gov (United States)

2013-03-26

...-AA08 Special Local Regulation; Low Country Splash, Wando River, Cooper River, and Charleston Harbor... proposes to issue a special local regulation on the waters of the Wando River, Cooper River, and Charleston... Country Splash is scheduled to take place on the waters of the Wando River, Cooper River, and Charleston...

Measuring river from the cloud - River width algorithm development on Google Earth Engine

Science.gov (United States)

Yang, X.; Pavelsky, T.; Allen, G. H.; Donchyts, G.

2017-12-01

Rivers are some of the most dynamic features of the terrestrial land surface. They help distribute freshwater, nutrients, sediment, and they are also responsible for some of the greatest natural hazards. Despite their importance, our understanding of river behavior is limited at the global scale, in part because we do not have a river observational dataset that spans both time and space. Remote sensing data represent a rich, largely untapped resource for observing river dynamics. In particular, publicly accessible archives of satellite optical imagery, which date back to the 1970s, can be used to study the planview morphodynamics of rivers at the global scale. Here we present an image processing algorithm developed using the Google Earth Engine cloud-based platform, that can automatically extracts river centerlines and widths from Landsat 5, 7, and 8 scenes at 30 m resolution. Our algorithm makes use of the latest monthly global surface water history dataset and an existing Global River Width from Landsat (GRWL) dataset to efficiently extract river masks from each Landsat scene. Then a combination of distance transform and skeletonization techniques are used to extract river centerlines. Finally, our algorithm calculates wetted river width at each centerline pixel perpendicular to its local centerline direction. We validated this algorithm using in situ data estimated from 16 USGS gauge stations (N=1781). We find that 92% of the width differences are within 60 m (i.e. the minimum length of 2 Landsat pixels). Leveraging Earth Engine's infrastructure of collocated data and processing power, our goal is to use this algorithm to reconstruct the morphodynamic history of rivers globally by processing over 100,000 Landsat 5 scenes, covering from 1984 to 2013.

Illuminance-based slat angle selection model for automated control of split blinds

Energy Technology Data Exchange (ETDEWEB)

Hu, Jia; Olbina, Svetlana [Rinker School of Building Construction, University of Florida, Gainesville, FL 32611-5703 (United States)

2011-03-15

Venetian blinds play an important role in controlling daylight in buildings. Automated blinds overcome some limitations of manual blinds; however, the existing automated systems mainly control the direct solar radiation and glare and cannot be used for controlling innovative blind systems such as split blinds. This research developed an Illuminance-based Slat Angle Selection (ISAS) model that predicts the optimum slat angles of split blinds to achieve the designed indoor illuminance. The model was constructed based on a series of multi-layer feed-forward artificial neural networks (ANNs). The illuminance values at the sensor points used to develop the ANNs were obtained by the software EnergyPlus trademark. The weather determinants (such as horizontal illuminance and sun angles) were used as the input variables for the ANNs. The illuminance level at a sensor point was the output variable for the ANNs. The ISAS model was validated by evaluating the errors in the calculation of the: 1) illuminance and 2) optimum slat angles. The validation results showed that the power of the ISAS model to predict illuminance was 94.7% while its power to calculate the optimum slat angles was 98.5%. For about 90% of time in the year, the illuminance percentage errors were less than 10%, and the percentage errors in calculating the optimum slat angles were less than 5%. This research offers a new approach for the automated control of split blinds and a guide for future research to utilize the adaptive nature of ANNs to develop a more practical and applicable blind control system. (author)

Blindness and Glaucoma: A Multicenter Data Review from 7 Academic Eye Clinics.

Science.gov (United States)

Rossetti, Luca; Digiuni, Maurizio; Montesano, Giovanni; Giovanni, Montesano; Centofanti, Marco; Fea, Antonio M; Iester, Michele; Frezzotti, Paolo; Figus, Michele; Ferreras, Antonio; Oddone, Francesco; Tanga, Lucia; Rolle, Teresa; Battaglino, Valentina; Posarelli, Chiara; Motolese, Ilaria; Mittica, Pietro; Bagaglia, Simone Alex; Menicacci, Cristina; De Cilla', Stefano; Autelitano, Alessandro; Fogagnolo, Paolo

2015-01-01

To evaluate frequency, conversion rate, and risk factors for blindness in glaucoma patients treated in European Universities. This multicenter retrospective study included 2402 consecutive patients with glaucoma in at least one eye. Medical charts were inspected and patients were divided into those blind and the remainder ('controls'). Blindness was defined as visual acuity≤0.05 and/or visual field loss to less than 10°. Unilateral and bilateral blindness were respectively 11.0% and 1.6% at the beginning, and 15.5% and 3.6% at the end of the observation period (7.5±5.5 years, range:1-25 years); conversion to blindness (at least unilateral) was 1.1%/year. 134 eyes (97 patients) developed blindness by POAG during the study. At the first access to study centre, they had mean deviation (MD) of -17.1±8.3 dB and treated intraocular pressure (IOP) of 17.1±6.6 mmHg. During follow-up the IOP decreased by 14% in these eyes but MD deteriorated by 1.1±3.5 dB/year, which was 5-fold higher than controls (0.2±1.6 dB/year). In a multivariate model, the best predictors for blindness by glaucoma were initial MD (pblindness occurred in about 20%. Blindness by glaucoma had 2 characteristics: late diagnosis and/or late referral, and progression of the disease despite in most cases IOP was within the range of normality and target IOP was achieved; it could be predicted by high initial MD, high initial IOP, and old age.

On the functional order of binocular rivalry and blind spot filling-in.

Science.gov (United States)

Qian, Cheng S; Brascamp, Jan W; Liu, Taosheng

2017-07-01

Binocular rivalry is an important phenomenon for understanding the mechanisms of visual awareness. Here we assessed the functional locus of binocular rivalry relative to blind spot filling-in, which is thought to transpire in V1, thus providing a reference point for assessing the locus of rivalry. We conducted two experiments to explore the functional order of binocular rivalry and blind spot filling-in. Experiment 1 examined if the information filled-in at the blind spot can engage in rivalry with a physical stimulus at the corresponding location in the fellow eye. Participants' perceptual reports showed no difference between this condition and a condition where filling-in was precluded by presenting the same stimuli away from the blind spot, suggesting that the rivalry process is not influenced by any filling-in that might occur. In Experiment 2, we presented the fellow eye's stimulus directly in rivalry with the 'inducer' stimulus that surrounds the blind spot, and compared it with two control conditions away from the blind spot: one involving a ring physically identical to the inducer, and one involving a disc that resembled the filled-in percept. Perceptual reports in the blind spot condition resembled those in the 'ring' condition, more than those in the latter, 'disc' condition, indicating that a perceptually suppressed inducer does not engender filling-in. Thus, our behavioral data suggest binocular rivalry functionally precedes blind spot filling-in. We conjecture that the neural substrate of binocular rivalry suppression includes processing stages at or before V1. Copyright © 2017 Elsevier Ltd. All rights reserved.

Navigation with a sensory substitution device in congenitally blind individuals.

Science.gov (United States)

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

2011-05-11

Vision allows for obstacle detection and avoidance. The compensatory mechanisms involved in maintaining these functions in blind people using their remaining intact senses are poorly understood. We investigated the ability of congenitally blind participants to detect and avoid obstacles using the tongue display unit, a sensory substitution device that uses the tongue as a portal to the brain. We found that congenitally blind were better than sighted control participants in detecting and avoiding obstacles using the tongue display unit. Obstacles size and avoidance strategy had a significant effect on performance: large obstacles were better detected than small ones and step-around obstacles were better avoided than step-over ones. These data extend our earlier findings that when using a sensory substitution device, blind participants outperform sighted controls not only in a virtual navigation task but also during effective navigation within a human-sized obstacle course.

Evaluation of the attentional capacities and working memory of early and late blind persons.

Science.gov (United States)

Pigeon, Caroline; Marin-Lamellet, Claude

2015-02-01

Although attentional processes and working memory seem to be significantly involved in the daily activities (particularly during navigating) of persons who are blind and who use these abilities to compensate for their lack of vision, few studies have investigated these mechanisms in this population. The aim of this study is to evaluate the selective, sustained and divided attention, attentional inhibition and switching and working memory of blind persons. Early blind, late blind and sighted participants completed neuropsychological tests that were designed or adapted to be achievable in the absence of vision. The results revealed that the early blind participants outperformed the sighted ones in selective, sustained and divided attention and working memory tests, and the late blind participants outperformed the sighted participants in selective, sustained and divided attention. However, no differences were found between the blind groups and the sighted group in the attentional inhibition and switching tests. Furthermore, no differences were found between the early and late blind participants in this set of tests. These results suggest that early and late blind persons can compensate for the lack of vision by an enhancement of the attentional and working memory capacities. Copyright © 2014 Elsevier B.V. All rights reserved.

78 FR 17087 - Special Local Regulation; New River Raft Race, New River; Fort Lauderdale, FL

Science.gov (United States)

2013-03-20

...-AA08 Special Local Regulation; New River Raft Race, New River; Fort Lauderdale, FL AGENCY: Coast Guard... on the New River in Fort Lauderdale, Florida during the Rotary Club of Fort Lauderdale New River Raft... States during the Rotary Club of Fort Lauderdale New River Raft Race. On March 23, 2013, Fort Lauderdale...

Methods of blinding in reports of randomized controlled trials assessing pharmacologic treatments: a systematic review.

Directory of Open Access Journals (Sweden)

Isabelle Boutron

2006-10-01

Full Text Available BACKGROUND: Blinding is a cornerstone of therapeutic evaluation because lack of blinding can bias treatment effect estimates. An inventory of the blinding methods would help trialists conduct high-quality clinical trials and readers appraise the quality of results of published trials. We aimed to systematically classify and describe methods to establish and maintain blinding of patients and health care providers and methods to obtain blinding of outcome assessors in randomized controlled trials of pharmacologic treatments. METHODS AND FINDINGS: We undertook a systematic review of all reports of randomized controlled trials assessing pharmacologic treatments with blinding published in 2004 in high impact-factor journals from Medline and the Cochrane Methodology Register. We used a standardized data collection form to extract data. The blinding methods were classified according to whether they primarily (1 established blinding of patients or health care providers, (2 maintained the blinding of patients or health care providers, and (3 obtained blinding of assessors of the main outcomes. We identified 819 articles, with 472 (58% describing the method of blinding. Methods to establish blinding of patients and/or health care providers concerned mainly treatments provided in identical form, specific methods to mask some characteristics of the treatments (e.g., added flavor or opaque coverage, or use of double dummy procedures or simulation of an injection. Methods to avoid unblinding of patients and/or health care providers involved use of active placebo, centralized assessment of side effects, patients informed only in part about the potential side effects of each treatment, centralized adapted dosage, or provision of sham results of complementary investigations. The methods reported for blinding outcome assessors mainly relied on a centralized assessment of complementary investigations, clinical examination (i.e., use of video, audiotape, or

Adapting diagrams from physics textbooks: improving the autonomy of blind students

Science.gov (United States)

Dickman, Adriana; Martins, Alexandre; Ferreira, Amauri

2014-03-01

In this work we elaborate and test a glossary consisting of a set of objects and their symbols. The symbols are designed to represent objects frequently used in mechanics diagrams, such as vectors, ropes, pulleys, blocks and surfaces, and can be used to adapt drawings of physics situations in textbooks for blind high school students. The educational product was tested at a specialized school for the blind. The results indicate that adequate training can help blind students to become familiar with the symbols, and to identify them in a problem without the need of a description. This educational product can help blind students to achieve the same conditions of autonomy as sighted ones, when studying physics. Research supported by CNPq, Capes, Fapemig and FIP/PUC-MG (Brazil).

Countermeasure against probabilistic blinding attack in practical quantum key distribution systems

International Nuclear Information System (INIS)

Qian Yong-Jun; Li Hong-Wei; He De-Yong; Yin Zhen-Qiang; Zhang Chun-Mei; Chen Wei; Wang Shuang; Han Zheng-Fu

2015-01-01

In a practical quantum key distribution (QKD) system, imperfect equipment, especially the single-photon detector, can be eavesdropped on by a blinding attack. However, the original blinding attack may be discovered by directly detecting the current. In this paper, we propose a probabilistic blinding attack model, where Eve probabilistically applies a blinding attack without being caught by using only an existing intuitive countermeasure. More precisely, our countermeasure solves the problem of how to define the bound in the limitation of precision of current detection, and then we prove security of the practical system by considering the current parameter. Meanwhile, we discuss the bound of the quantum bit error rate (QBER) introduced by Eve, by which Eve can acquire information without the countermeasure. (paper)

Human impacts on river water quality- comparative research in the catchment areas of the Tone River and the Mur River-

Science.gov (United States)

Kogure, K.

2013-12-01