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Sample records for didelphys blind hemivagina

  1. Novel use of a tracheobronchial stent in a patient with uterine didelphys and obstructed hemivagina

    PubMed Central

    Cooper, Amber R.; Merritt, Diane F.

    2014-01-01

    Objective: To describe a novel use for a tracheobronchial stent to maintain patency after vaginal septum excision in a patient with an obstructed hemivagina and uterine didelphys. Design: Description of a novel technique Setting: University-affiliated Children’s Hospital Patient: One patient with an obstructed hemivagina and uterine didelphys who presented with hematometria and hematocolpos. Intervention: In order to maintain patency and decrease stenosis risk after vaginal septum excision, a coated tracheobronchial stent was deployed and left in place for 6 weeks. Main Outcome Measure: To evaluate ease of stent placement and removal, re-epithelialization and patency of the neo-vagina, and post-operative assessment of pain and recurrent obstruction. Results: The tracheobroncheal stent was easily positioned and deployed with vaginoscopic guidance. Six weeks later it was removed without any tissue in-growth or granulation tissue noted. The vaginal walls were nicely epithelialized. Twelve months post-operatively the patient remained pain free with regular cycles and no evidence of obstruction or abnormality on ultrasound. Conclusion: Use of a coated tracheobronchial stent to maintain patency after septum excision in a patient with an obstructed hemivagina presents a safe, easy and effective option to diminish stenosis risk and avoid infectious complications or hysterectomy. PMID:19064265

  2. [Obstructed hemivagina and ipsilateral renal anomaly: unusual cause of piocolpos. Report a case and review of literature ].

    PubMed

    Cortés-Contreras, Diana Karen; Juárez-Cruz, Patricio Manuel; Vázquez-Flores, José; Vázquez-Flores, Al David

    2014-10-01

    OHVIRA (Obstructed hemivagina and ipsilateral renal anomaly) by acronym and abbreviations in English or Herlyn Werner Wunderlich syndrome is a rare congenital malformation caused by an alteration in the Mullerian ducts and Wolffian Ducts. Which is characterized by a triad: uterus didelphys, obstructed and ipsilateral renal agenesis hemivagina still uncertain etiology. Patients are usually asymptomatic until menarche where the most common clinical presentation is pelvic pain, followed by a vaginal or abdominal mass, normal menstrual periods, infertility, and vaginal discharge rarely appears. The case of a female patient of 15 years, nubile with chronic fetid vaginal discharge, initially diagnosed and treated as pelvic inflammatory disease occurs, however because it is an exceptional condition with the background of the patient, by complementary studies were conducted where pelvic ultrasound revealed pyocolpos and absence of left kidney, uterus didelphys, blind hemivagina by other imaging studies, where we could integrate Herlyn-Werner-Wunderlich syndrome. In conclusion, abnormalities in the development of the Miillerian ducts are difficult to diagnose early, so you must have the embryological knowledge, conduct thorough clinical assessment and detailed picture in whom the coridition is suspected to identify malformations coexisting urinary tract and vaginal defects with the importance of preserving reproductive success through appropriate planning of surgical approach, given that the fertility rate in these patients is comparable to the average.

  3. [Müllerian anomalies. Obstructed hemivagina and ipsilateral renal anomaly syndrome (OHVIRA)].

    PubMed

    Afrashtehfar, Cyrus Dean Mario; Piña-García, Adrián; Afrashtehfar, Kelvin Ian

    2014-01-01

    Müllerian duct anomalies are a group of uncommon and underdiagnosed entities, which cause specific symptoms in adolescent females and may be associated with infertility as well as adverse pregnancy outcomes. These malformations occur as a result of an arrest or abnormal development of the Müllerian ducts in different stages of the female reproductive tract during gestation. Obstructed hemivagina and ipsilateral renal anomaly syndrome (OHVIRA), formerly known as the Herlyn-Werner-Wunderlich syndrome, is a rare entity characterized by the presence of a uterus didelphys with an obstructed hemivagina cause by a vaginal septum and the association of a renal anomaly (most commonly renal agenesis) ipsilateral to the obstruction. This syndrome may remain undiagnosed during childhood and usually becomes symptomatic after menarche, causing obstructive symptoms. Occasionally it may be identified after the evaluation of a patient with infertility or recurrent pregnancy loss. The clinical diagnosis is very challenging and requires imaging studies in which ultrasound and MRI play an essential role in the diagnosis, classification and treatment plan. Opportune diagnosis and treatment achieve complete improvement of symptoms, adequate reproductive prognosis and avoid major complications such as endometriosis, pelvic adhesions and infertility. The purpose of this review is to demonstrate the pathophysiology, clinical manifestations, diagnostic methods and treatment of the obstructed hemivagina and ipsilateral renal anomaly syndrome.

  4. Wolffian Origin of Vagina Unfolds the Embryopathogenesis of OHVIRA (Obstructed Hemivagina and Ipsilateral Renal Anomaly) Syndrome and Places OHVIRA as a Female Counterpart of Zinner Syndrome in Males

    PubMed Central

    Aswani, Yashant; Varma, Ravi; Choudhary, Pradeep; Gupta, Reeta B.

    2016-01-01

    Summary Background The classical theory of Müllerian origin of upper vagina fails to explain complex urogenital malformations like OHVIRA syndrome; the Acien’s hypothesis, however, unravels the hidden embryopathogenesis. As per Acien, Wolffian (mesonephric) ducts instead of Müllerian ducts and sinovaginal bulbs, give rise to the vagina. The new hypothesis, however, retains the concept of origin of the ureters (with ureters inducing renal development) by the former and the uterus by Müllerian ducts. Thus, a failure of development of mesonephros/mesonephric duct gives rise to absent ureters and hence absent homolateral kidney; blind ending (obstructed) ipsilateral hemivagina and cessation of support to paramesonephric ducts which leads to unfused uterus (uterus didelphys). Hence, the new hypothesis explains all components of OHVIRA syndrome. On a parallel track, unilateral anomalous development of the mesonephros in males causes atresia of the homolateral ejaculatory duct that results in obstruction of the proximally placed seminal vesicle. Besides, there is absence of the ipsilateral kidney (Zinner syndrome). Case Report In this manuscript, we describe four cases of OHVIRA syndrome. Case 1 was a 34-year-old nulligravida, married since fourteen years, who presented with a 5-month history of pelvic inflammatory disease and dyspareunia. Regular menses in the patient and azoospermia in her husband delayed the diagnosis. Case 2 was a 14-year-old girl who presented with dysmenorrhea and lower abdominal pain since a few months. Case 3 was a 27-year-old female who presented with infertility and dysmenorrhea. Case 4 was a 15-year-old female who presented with a one-year history of dysmenorrhea and cyclic pelvic pain. In all cases, one of the uterine horns revealed collection due to a hemivaginal septum and an absent ipsilateral kidney; thus, establishing the diagnosis of OHVIRA syndrome. The case 4 additionally revealed homolateral vaginal agenesis. Conclusions On the

  5. Successful laparoscopic transabdominal cerclage in uterus didelphys.

    PubMed

    Ades, Alex; Hong, Phoebe

    2015-11-17

    The incidence of uterus didelphys is around 3/10,000 women. It is a class III Müllerian duct anomaly resulting from a complete non-fusion of the paired Müllerian ducts between the 12th and 16th weeks of gestation. Although the prevalence of cervical insufficiency in women with uterus didelphys is unknown, the incidence of cervical insufficiency in women with Müllerian anomalies has been reported as high as 30%. We present a case of successful pregnancy outcome following a laparoscopic transabdominal cerclage in a woman with uterus didelphys and cervical insufficiency. The case demonstrates that laparoscopic transabdominal cerclage can be performed successfully in women with uterus didelphys and a satisfactory obstetric outcome can be achieved.

  6. Blindness

    MedlinePlus

    ... de los dientes Video: Getting an X-ray Blindness KidsHealth > For Kids > Blindness Print A A A ... help, are sometimes called "legally blind." What Causes Blindness? Vision problems can develop before a baby is ...

  7. Blindness

    MedlinePlus

    ... Emergency Room? What Happens in the Operating Room? Blindness KidsHealth > For Kids > Blindness A A A What's ... help, are sometimes called "legally blind." What Causes Blindness? Vision problems can develop before a baby is ...

  8. Sonographic diagnosis of Obstructed Hemivagina and Ipsilateral Renal Anomaly Syndrome: a report of two cases

    PubMed Central

    Ng, Stanley

    2015-01-01

    Abstract Obstructed hemivagina and ipsilateral renal anomaly (OHVIRA) syndrome is a rare urogenital anomaly. Patients typically present at puberty, shortly after menarche with increasing pelvic pain, dysmenorrhea and pelvic mass. There may be a known history of unilateral renal agenesis. Diagnosis can usually be established by ultrasound or magnetic resonance imaging. Resection of the vaginal septum is the treatment of choice. Early diagnosis and treatment can relieve symptoms, prevent complications and preserve fertility. We present two cases of OHVIRA syndrome diagnosed by ultrasound to promote recognition of this rare but important condition. PMID:28191231

  9. Clinical Implications of Obstructed Hemivagina and Ipsilateral Renal Anomaly (OHVIRA) Syndrome in the Prepubertal Age Group

    PubMed Central

    Han, Jang Hee; Lee, Yong Seung; Im, Young Jae; Kim, Sang Woon; Lee, Mi-Jung; Han, Sang Won

    2016-01-01

    Purpose Obstructed hemivagina and ipsilateral renal anomaly (OHVIRA) syndrome is a rare syndrome characterized by Müllerian duct and renal anomalies. It is usually regarded as a disease of adolescence; however, due to a number of possible problems, the management of patients before puberty should not be overlooked. We assessed the clinical course of prepubertal patients to propose appropriate management. Materials and Methods We retrospectively assessed 43 prepubertal OHVIRA syndrome patients who were diagnosed and followed up at our institution from July 2004 to June 2015. We reviewed medical records, focusing on presentation, radiologic findings, surgical management, and the overall clinical course. Results Median age at diagnosis was 1.3 months and median follow-up period was 25.5 months. The most common accompanying ipsilateral urologic anomalies were ectopic ureter and ureterocele, while the most common contralateral anomaly was vesicoureteral reflux. During the follow-up period, six patients (14.0%) required surgery at a median age of 31.2 months due to recurrent urinary tract infection, uncontrolled vaginal distention compressing adjacent organs, urinary incontinence, or intractable abdominal pain. Conclusions While OHVIRA syndrome is known as a postpubertal disease, about 13% of prepubertal patients in our study required surgery. When ectopic ureter insertion into the vagina is present, further treatment may be needed to address the complications caused by continuous urine production. Patients should be monitored for complications arising from either obstructed hemivagina or renal anomalies with regular follow-up, especially before the age of five years. PMID:27861623

  10. Superfetation in uterus pseudo didelphys: an unreported event.

    PubMed

    Singhal, Savita Rani; Agarwal, Umber; Sharma, Damyanti; Sen, Jyotsna

    2003-08-01

    A 20-year-old primigravida initially diagnosed at 28 weeks to have superfetation in a case of a bicornuate uterus was subsequently found to have uterus pseudo didelphys during a cesarean section at 35 weeks. This type of uterine anomaly with twin gestation has been previously reported in five case reports, but superfetation with such müllerian abnormality has not been previously described.

  11. Besnoitia darlingi infection in a Virginia opossum (Didelphis virginiana).

    PubMed

    Shaw, Shannon; Grasperge, Britton; Nevarez, Javier; Reed, Scott; Long, Lauren; Rademacher, Nathalie; Sánchez-Migallón Guzmán, David

    2009-03-01

    This is a case report of natural infection with Besnoitia darlingi in a Virginia opossum (Didelphis virginiana) in Louisiana. Clinical pathologic data included a severe nonregenerative anemia, inflammatory leukogram, increased hepatocellular leakage enzymes, renal azotemia, hyperkalemia, hypoglycemia, hypoalbuminemia, and proteinuria. Tissue cysts containing bradyzoites were found in the majority of organs, especially the skin, mucous membranes, kidneys, adrenals, lungs, and heart. Images of the bradyzoites obtained by transmission electron microscopy were consistent with the previously described ultrastructure of Besnoitia darlingi. This opossum also suffered from an open phalangeal fracture and concurrent gastrointestinal parasites. Histopathologic findings included a glomerulonephritis and hepatic necrosis.

  12. Anatomical study of the opossum (Didelphis albiventris) extraocular muscles.

    PubMed Central

    Matheus, S M; Soares, J C; da Silva, A M; Seullner, G

    1995-01-01

    The anatomy of the extraocular muscles was studied in 10 adult opossums (Didelphis albiventris) of both sexes. Eight extraocular muscles were identified: 4 rectus muscles, 2 oblique muscles, the levator palpebrae superioris and the retractor ocular bulbi. The rectus muscles originate very close one to another between the orbital surfaces of the presphenoid and palatine bones. These muscles diverge on the way to their insertion which occurs at about 2 mm from the limbus. The levator palpebrae superioris originates with the dorsal rectus and is positioned dorsally in relation to it. The retractor ocular bulbi forms a cone which embraces the optic nerve and is located internally in relation to the rectus muscles. The dorsal oblique originates on the presphenoid bone and after a tendinous trajectory through a trochlea on the medial wall of the orbit, inserts into the ocular bulb. The only muscle arising from the anterior orbital floor is the ventral oblique. The main nerve supply for these muscles is the oculomotor, except for the dorsal oblique which is innervated by the trochlear nerve, and the lateral rectus which is innervated by the abducens nerve. The retractor ocular bulbi receives branches from the inferior division of the oculomotor nerve and some branches from the abducens nerve. Images Fig. 1 Fig. 2 Fig. 3 PMID:7649843

  13. West Nile Virus Isolated from a Virginia Opossum (Didelphis virginiana) in Northwestern Missouri, USA, 2012

    PubMed Central

    Bosco-Lauth, Angela; Harmon, Jessica R.; Lash, R. Ryan; Weiss, Sonja; Langevin, Stanley; Savage, Harry M.; Godsey, Marvin S.; Burkhalter, Kristen; Root, J. Jeffrey; Gidlewski, Thomas; Nicholson, William L.; Brault, Aaron C.; Komar, Nicholas

    2016-01-01

    We describe the isolation of West Nile virus (WNV; Flaviviridae, Flavivirus) from blood of a Virginia opossum (Didelphis virginiana) collected in northwestern Missouri, USA in August 2012. Sequencing determined that the virus was related to lineage 1a WNV02 strains. We discuss the role of wildlife in WNV disease epidemiology. PMID:25098303

  14. West Nile virus isolated from Virginia opossum (Didelphis virginiana) in Northwest Missouri 2012

    DOE PAGES

    Bosco-Lauth, Angela; Harmon, Jessica; Lash, R. Ryan; ...

    2014-12-01

    We describe the isolation of West Nile virus (WNV; Flaviviridae, flavivirus) from blood of a Virginia opossum (Didelphis virginiana) collected in northwestern Missouri, USA in August 2012. Furthermore, sequencing determined that the virus was related to lineage 1a WNV02 strains. We discuss the role of wildlife in WNV disease epidemiology.

  15. Experimental infection of Didelphis marsupialis with Vesicular Stomatitis New Jersey Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although vesicular stomatitis has been present for many years in the Americas, many aspects of its natural history remain undefined. In this study we challenged five adult Virginia opossums (Didelphis marsupialis) with vesicular stomatitis New Jersey serotype virus (VSNJV). Opossums had no detecta...

  16. Toxocara cati (Nematoda: Ascarididae) in Didelphis albiventris (Marsupialia: Didelphidae) from Brazil: a case of pseudoparasitism.

    PubMed

    Pinto, Hudson Alves; Mati, Vitor Luís Tenório; Melo, Alan Lane de

    2014-01-01

    Eggs of Toxocara cati were found in the feces of Didelphis albiventris from a peridomestic urban environment in Brazil. Negative fecal tests following short-term captivity of the opossums, as well as the absence of ascaridids during necropsy, suggest the occurrence of pseudoparasitism. Implications of the findings for the epidemiology of toxocariasis are discussed.

  17. Blindness - resources

    MedlinePlus

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

  18. INFECTION BY Rickettsia felis IN OPOSSUMS (Didelphis sp.) FROM YUCATAN, MEXICO.

    PubMed

    Peniche-Lara, Gaspar; Ruiz-Piña, Hugo A; Reyes-Novelo, Enrique; Dzul-Rosado, Karla; Zavala-Castro, Jorge

    2016-01-01

    Rickettsia felis is an emergent pathogen and the causative agent of a typhus-like rickettsiosis in the Americas. Its transmission cycle involves fleas as biological vectors (mainly Ctenocephalides felis) and multiple domestic and synanthropic mammal hosts. Nonetheless, the role of mammals in the cycle of R. felis is not well understood and many efforts are ongoing in different countries of America to clarify it. The present study describes for the first time in Mexico the infection of two species of opossum (Didelphis virginiana and D. marsupialis) by R. felis. A diagnosis was carried out from blood samples by molecular methods through the gltA and 17 kDa genes and sequence determination. Eighty-seven opossum samples were analyzed and 28 were found to be infected (32.1%) from five out of the six studied localities of Yucatan. These findings enable recognition of the potential epidemiological implications for public health of the presence of infected synanthropic Didelphis in households.

  19. Independent uterine contractions in simultaneous twin pregnancy in each horn of the uterus didelphys.

    PubMed

    Maki, Yohei; Furukawa, Seishi; Sameshima, Hiroshi; Ikenoue, Tsuyomu

    2014-03-01

    The mechanism of synchronizing uterine contractions is not fully understood. We present a case of twin pregnancy in a uterus didelphys and objectively analyze the synchrony of bilateral uterine contractions. A 32-year-old woman, with a history of vaginal septal resection during her previous vaginal delivery, became pregnant with twins in a uterus didelphys in which each uterine horn had one fetus. At 37 weeks and 6 days, the first baby was delivered vaginally. The second baby was delivered by cesarean section due to recurrent late decelerations. Operative findings confirmed the didelphys uterus. We retrospectively reviewed the timing of contractions of both uteruses. The timing was determined by visual analysis as synchronous if both uteruses contracted within 5 s. Otherwise, contractions were considered solitary. Both uterine horns contracted independently in 90% of the incidence throughout labor and delivery. From this rare case of an 'experiment by nature', we speculated that the myometrium must be histologically connected in order to synchronize uterine contractions.

  20. Natural infection of Didelphis aurita (Mammalia: Marsupialia) with Leishmania infantum in Brazil

    PubMed Central

    2012-01-01

    Background The opossum Didelphis have been considered as natural hosts of Leishmania parasites in the New World, suggesting an important role in the epidemiology of Visceral Leishmaniasis (VL). Among six extant species that belong to the genus Didelphis, only two (D. marsupialis and D. albiventris), have been mentioned as natural hosts of Leishmania infantum in Brazil and Colombia. In the present paper, it is reported for the first time, the observation of intracellular parasites (amastigotes) in tissues of Didelphis aurita naturally infected with Leishmania infantum in Brazil. We also discuss some aspects associated to the relationship between L. infantum and the geographical distribution of some species of the genus Didelphis. Methods The opossums studied were caught by wire traps (Tomahawk) in Barra de Guaratiba, a peri-urban area in Rio de Janeiro. The opossums were killed with an overdose of Thiopental sodium.At necropsy, macroscopic alterations were examined and samples from liver, spleen, lymph nodes, ear, abdominal skin, scent glands and bone marrow were collected for parasitological and molecular diagnoses. Results Forty-eight opossums were captured in an AVL endemic region, 30 being caught in a mangrove area and eighteen animals in a forest area near to some residential-yards. Among the thirty opossums trapped in the mangrove area, all of them were negative by both imprint and sera samples assayed on Dipstick Tests, that is a test based on a combination of protein-A colloidal gold conjugate and rk39 Leishmania antigen to detect anti-Leishmania antibody in serum or plasma. At the macroscopic examination one out of eighteen opossums, caught close to the forest, presented alterations compatible with spleen hypertrophy and three were positive by Dipstick Tests (16.6%) and presented amastigotes in the spleen and in one of them, the parasites were also observed in a submandibular lymph node. Leishmania infantum infections were confirmed through dot blot

  1. Trypanosoma (Herpetosoma) leeuwenhoeki in Choloepus hoffmanni and Didelphis marsupialis of the Pacific Coast of Colombia.

    PubMed

    Travi, B L; Zea, A; D'Alessandro, A

    1989-04-01

    Trypanosoma (Herpetosoma) leeuwenhoeki, originally described in Panamanian sloths, was isolated from Didelphis marsupialis (Marsupialia) and Choloepus hoffmanni (Edentata) inhabiting the Pacific coast of Colombia. Trypanosomes were characterized by their large blood forms (total length 51-53 microns), poor infectivity for mice, and lack of development in Rhodnius prolixus. Isoenzyme studies, with either strains or clones, revealed homogeneous profiles clearly distinct from Trypanosoma cruzi and Trypanosoma rangeli reference strains. The present report extends the geographical distribution of T. leeuwenhoeki to South America and broadens its known host range to another order of mammals.

  2. Congenital pouch colon in a girl associated with bilateral atresia of cervix uteri and uterus didelphys.

    PubMed

    Chadha, Rajiv; Puri, Manju; Saxena, Rahul; Agarwala, Surendrakumar; Puri, Archana; Choudhury, Subhasis Roy

    2013-04-01

    This report describes a girl with congenital pouch colon (CPC), uterus didelphys with septate vagina, and a cloacal anomaly. The girl underwent cloacal reconstruction at the age of 15 months. Subsequently, at puberty, the child had primary amenorrhea with severe cyclic abdominal pain due to endometriosis of both the uteruses and adnexal cysts with hematometra and hematosalpinx. Laparotomy with removal of both uteri and the left fallopian tube was performed. Both uteri had atresia of the cervix uteri. This report emphasizes the need for comprehensive evaluation and a long-term management strategy for associated gynecologic anomalies in girls with CPC, especially with regard to patency of the outflow tract.

  3. INFECTION BY Rickettsia felis IN OPOSSUMS (Didelphis sp.) FROM YUCATAN, MEXICO

    PubMed Central

    PENICHE-LARA, Gaspar; RUIZ-PIÑA, Hugo A.; REYES-NOVELO, Enrique; DZUL-ROSADO, Karla; ZAVALA-CASTRO, Jorge

    2016-01-01

    Rickettsia felis is an emergent pathogen and the causative agent of a typhus-like rickettsiosis in the Americas. Its transmission cycle involves fleas as biological vectors (mainly Ctenocephalides felis) and multiple domestic and synanthropic mammal hosts. Nonetheless, the role of mammals in the cycle of R. felis is not well understood and many efforts are ongoing in different countries of America to clarify it. The present study describes for the first time in Mexico the infection of two species of opossum (Didelphis virginiana and D. marsupialis) by R. felis. A diagnosis was carried out from blood samples by molecular methods through the gltAand 17 kDa genes and sequence determination. Eighty-seven opossum samples were analyzed and 28 were found to be infected (32.1%) from five out of the six studied localities of Yucatan. These findings enable recognition of the potential epidemiological implications for public health of the presence of infected synanthropic Didelphis in households. PMID:27074326

  4. West Nile virus isolated from Virginia opossum (Didelphis virginiana) in Northwest Missouri 2012

    SciTech Connect

    Bosco-Lauth, Angela; Harmon, Jessica; Lash, R. Ryan; Weiss, Sonja; Langevin, Stanley; Savage, Harry; Marvin S. Godsey, Jr.; Burkhalter, Kristen; Root, J. Jeffrey; Gidlewski, Thomas; Nicholson, William; Brault, Aaron C.; Komar, Nicholas

    2014-12-01

    We describe the isolation of West Nile virus (WNV; Flaviviridae, flavivirus) from blood of a Virginia opossum (Didelphis virginiana) collected in northwestern Missouri, USA in August 2012. Furthermore, sequencing determined that the virus was related to lineage 1a WNV02 strains. We discuss the role of wildlife in WNV disease epidemiology.

  5. Prevalence of antibodies to Trypanosoma cruzi, Toxoplasma gondii, Encephalitozonn cuniculi, Sarcocystis neurona, Besnoitia darlingi, and Neospora caninum in North American opossum, Didelphis virginiana, from Southern Louisian

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We examined the prevalence of antibodies to zoonotic protozoan parasites (Trypanosoma cruzi, Toxoplasma gondii, and Encephalitozoon cuniculi) and protozoan’s of veterinary importance (Neospora caninum, Sarcocystis neurona and Besnoitia darlingi) in a population of North American opossums (Didelphis...

  6. Postmortem scavenging by the Virginia opossum (Didelphis virginiana): Impact on taphonomic assemblages and progression.

    PubMed

    King, Kama A; Lord, Wayne D; Ketchum, Heather R; O'Brien, R Christopher

    2016-09-01

    The Virginia opossum (Didelphis virginiana) is a highly active scavenger whose behavior has significant impacts on rates of decomposition and skeletonization, which have previously not been addressed. In this study, scavenging by the opossum led to the skeletonization of carcasses in half of the accumulated degree days (ADD) of a comparable non-scavenged control carcass. Opossums used body orifices, as well as natural tears caused by the decomposition process, to access internal tissues and consume them. This activity resulted in little movement of the carcass and the retained appearance of natural undisturbed decomposition. This concealed activity has the potential to cause drastically incorrect estimates of time since deposition and post-mortem interval. Scavenging by opossums was also found to leave distinct tooth mark and other defects on bone, which have not been previously distinguished in the literature. This research suggests, beyond effects on PMI, that scavenging by opossums has been historically overlooked and misattributed to canid scavengers.

  7. Normal conjunctival flora in the North American opossum (Didelphis virginiana) and raccoon (Procyon lotor).

    PubMed

    Pinard, Chantale L; Brightman, Alan H; Yeary, Teresa J; Everson, Troy D; Cox, Linda K; Chengappa, M M; Davidson, Harriet J

    2002-10-01

    We documented the normal conjunctival bacterial flora from 17 opossums (Didelphis virginiana) and 10 raccoons (Procyon lotor) trapped in Manhattan, Kansas (USA) from November 1999 to January 2000. Both raccoons and opossums were free of apparent ocular disease. The inferior conjunctival sacs of each animal were swabbed for aerobic bacterial and Mycoplasma culture and polymerase chain reaction (PCR) for Mycoplasma and Chlamydia detection. All conjunctival samples were positive for one or more species of aerobic bacteria. The most common isolate from opossums was Staphylococcus spp. Other isolates included Streptococcus spp., Bacillus spp., Corynebacterium spp., and Enterococcus faecalis. The most common isolates in raccoons was Bacillus spp. Other isolates included Streptococcus spp., Staphylococcus spp., non-hemolytic Escherichia coli, and Enterococcus faecalis. Mycoplasma culture was negative in samples from opossums and raccoons. Evidence of Mycoplasma and Chlamydia presence was detected by PCR.

  8. Mammary glands in male marsupials: I. Primordia in neonatal opossums Didelphis virginiana and Monodelphis domestica.

    PubMed

    Renfree, M B; Robinson, E S; Short, R V; Vandeberg, J L

    1990-10-01

    Neonates of the American didelphid marsupials Didelphis virginiana and Monodelphis domestica were sexed by karyotype and histologically examined on the day of birth. Mammary anlagen were found in both sexes of both species, but the neonatal males had less than one-third of the full female complement of mammary glands. Male neonates of both species also had paired scrotal bulges anterior to the genital tubercle but these were never present in females, once again raising the question of whether the pouch and scrotum are homologous structures. Mammary anlagen are not found in male neonates of the Australian marsupial species so far studied, which suggests a dichotomy in the control of some aspects of sexual differentiation in the two marsupial lineages.

  9. First molecular evidence of Toxoplasma gondii in opossums (Didelphis virginiana) from Yucatan, Mexico

    PubMed Central

    Torres-Castro, M.; Noh-Pech, H.; Puerto-Hernández, R.; Reyes-Hernández, B.; Panti-May, A.; Hernández-Betancourt, S.; Yeh-Gorocica, A.; González-Herrera, L.; Zavala-Castro, J.; Puerto, F.I.

    2016-01-01

    Toxoplasma gondii is an obligate intracellular parasite recognized as a causal agent of toxoplasmosis; zoonotic disease endemic in many countries worldwide, including Mexico. Different species of animals participate in the wild cycle infection, including opossums of the species Didelphis virginiana. Thirteen D. virginiana were captured in Yucatan, Mexico. Detection of T. gondii was achieved by Polymerase Chain Reaction, which determined an infection of 76.9% (10/13) in brains. Positive amplicons were sequenced for analysis, this produced results similar to T. gondii with identity and coverage values of 98% and 96-100%, respectively. This study presents the first molecular evidence of the circulation of T. gondii in D. virginiana from Mexico. PMID:27200271

  10. First molecular evidence of Toxoplasma gondii in opossums (Didelphis virginiana) from Yucatan, Mexico.

    PubMed

    Torres-Castro, M; Noh-Pech, H; Puerto-Hernández, R; Reyes-Hernández, B; Panti-May, A; Hernández-Betancourt, S; Yeh-Gorocica, A; González-Herrera, L; Zavala-Castro, J; Puerto, F I

    2016-01-01

    Toxoplasma gondii is an obligate intracellular parasite recognized as a causal agent of toxoplasmosis; zoonotic disease endemic in many countries worldwide, including Mexico. Different species of animals participate in the wild cycle infection, including opossums of the species Didelphis virginiana. Thirteen D. virginiana were captured in Yucatan, Mexico. Detection of T. gondii was achieved by Polymerase Chain Reaction, which determined an infection of 76.9% (10/13) in brains. Positive amplicons were sequenced for analysis, this produced results similar to T. gondii with identity and coverage values of 98% and 96-100%, respectively. This study presents the first molecular evidence of the circulation of T. gondii in D. virginiana from Mexico.

  11. Color blindness

    MedlinePlus

    ... have trouble telling the difference between red and green. This is the most common type of color ... color blindness often have problems seeing reds and greens, too. The most severe form of color blindness ...

  12. Blind Astronomers

    NASA Astrophysics Data System (ADS)

    Hockey, Thomas A.

    2011-01-01

    The phrase "blind astronomer” is used as an allegorical oxymoron. However, there were and are blind astronomers. What of famous blind astronomers? First, it must be stated that these astronomers were not martyrs to their craft. It is a myth that astronomers blind themselves by observing the Sun. As early as France's William of Saint-Cloud (circa 1290) astronomers knew that staring at the Sun was ill-advised and avoided it. Galileo Galilei did not invent the astronomical telescope and then proceed to blind himself with one. Galileo observed the Sun near sunrise and sunset or through projection. More than two decades later he became blind, as many septuagenarians do, unrelated to their profession. Even Isaac Newton temporarily blinded himself, staring at the reflection of the Sun when he was a twentysomething. But permanent Sun-induced blindness? No, it did not happen. For instance, it was a stroke that left Scotland's James Gregory (1638-1675) blind. (You will remember the Gregorian telescope.) However, he died days later. Thus, blindness little interfered with his occupation. English Abbot Richard of Wallingford (circa 1291 - circa 1335) wrote astronomical works and designed astronomical instruments. He was also blind in one eye. Yet as he further suffered from leprosy, his blindness seems the lesser of Richard's maladies. Perhaps the most famous professionally active, blind astronomer (or almost blind astronomer) is Dominique-Francois Arago (1786-1853), director until his death of the powerful nineteenth-century Paris Observatory. I will share other _ some poignant _ examples such as: William Campbell, whose blindness drove him to suicide; Leonhard Euler, astronomy's Beethoven, who did nearly half of his life's work while almost totally blind; and Edwin Frost, who "observed” a total solar eclipse while completely sightless.

  13. [Cortical blindness].

    PubMed

    Chokron, S

    2014-02-01

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

  14. [Global blindness].

    PubMed

    Schulze Schwering, M

    2007-10-01

    Worldwide there are 37 million people who are completely blind and another 112 million whose sight is severely restricted. Of all blind people throughout the world, 85% live in developing countries. In three quarters of cases, blindness could be prevented or treated. The VISION 2020 campaign is dedicated to halving the number of people suffering from the diseases leading to blindness by means of disease control, training of specialist ophthalmic staff and development of appropriate infrastructures. More effort is needed if these goals are to be met. German ophthalmologists engaged in conservative and surgical treatments who join in and support VISION 2020 will be welcomed.

  15. CUTANEOUS EPITHELIOTROPIC T-CELL LYMPHOMA WITH METASTASES IN A VIRGINIA OPOSSUM (DIDELPHIS VIRGINIANA).

    PubMed

    Higbie, Christine T; Carpenter, James W; Choudhary, Shambhunath; DeBey, Brad; Bagladi-Swanson, Mary; Eshar, David

    2015-06-01

    A 2-yr-old, captive, intact female Virginia opossum ( Didelphis virginiana ) with a 7-mo history of ulcerative dermatitis and weight loss was euthanatized for progressive worsening of clinical signs. Initially the opossum was treated with several courses of antibiotics, both topically and systemically; systemic nonsteroidal anti-inflammatory medication; and, later, systemic glucocorticoids, with no improvement in clinical signs. Histopathologic samples of skin lesions taken 3 mo into the course of disease revealed no evidence of neoplasia; however, cytologic samples of a skin lesion taken 5 mo into the course of disease revealed mature lymphocytes, and were suggestive of cutaneous lymphoma. Postmortem histopathology revealed neoplastic cells consistent with lymphoma; these were found in the haired skin of the forearm, axilla, hind limb, face, and lateral body wall, as well as the liver, kidney, axillary lymph node, heart, and spleen. Multifocal neutrophilic and eosinophilic ulcerative and necrotizing dermatitis and folliculitis of the haired skin were also present. To the authors' knowledge, this is the first documented case of cutaneous lymphoma in a Virginia opossum and the first documented case with visceral metastases in a marsupial.

  16. Observations on besnoitiosis in Virginia opossum (Didelphis virginiana) from Michigan, USA.

    PubMed

    El Sheikha, Hany M; Hussein, Hussein S; Monib, Mohammad el-Salahy M; Mansfield, Linda S

    2007-04-01

    Besnoitia tissue cysts were found in five naturally-infected adult opossums (Didelphis virginiana) from Michigan. Details of the microscopy, histopathology, ultra-structure, and genetic features of the cysts were studied to identify their species-specific traits. The materials were differentiated phenotypically from cysts of other Besnoitia spp. by difference in size, pattern of tissue distribution, morphology of pellicle and nucleus, number of micronemes and rhoptries, amount of lipids and amylopectin, and presence of enigmatic bodies. Morphometric variations identified the tissue cysts and the pathologic changes in opossums host to be due to B. darlingi. The data were proved by phylogenetic analysis based on DNA sequences of the first internal transcribed spacer of nuclear rDNA. Cluster analysis showed that B. darlingi was distinct from all other Besnoitia spp. as two distinct phylogenetic clades: I- included Besnoitia spp. described from opossum (B. darlingi), sheep (B. jellisoni), rodent (B. akadoni) and rabbit (B. oryctofelisi) and clade II- encompassed parasites described from cattle (B. besnoiti), equids (B. bennetti) and reindeer (B. tarandi). The genetic attributed particular to the genus Besnoitia complemented the morphologica features and lead to accurate delimitation of Besnoitia species.

  17. Leptospira borgpetersenii from free-living white-eared opossum (Didelphis albiventris): first isolation in Brazil.

    PubMed

    Jorge, Sérgio; Hartleben, Cláudia P; Seixas, Fabiana K; Coimbra, Marco A A; Stark, Cledir B; Larrondo, Adriana G; Amaral, Marta G; Albano, Ana Paula N; Minello, Luiz F; Dellagostin, Odir A; Brod, Claudiomar S

    2012-11-01

    Leptospirosis is a zoonotic disease that occurs all over the world, caused by bacteria of the genus Leptospira. Marsupial and didelphidae families are considered susceptible to infection caused by a wide range of Leptospira serovars for which they serve as reservoirs. Thirty-three free-living white-eared opossums (Didelphis albiventris) were captured in Southern Brazil and bodily fluids were collected. From the urine samples it was possible to obtain an isolate identified as Leptospira borgpetersenii by rpoB gene sequencing and belonging to serovar Castellonis by Multilocus Variable-Number Tandem-Repeat Analysis. This is the first report of the isolation of Leptospira spp. from the white-eared opossum in Brazil. In addition, the new strain was also virulent in the hamster model of lethal leptospirosis. The microscopic agglutination test (MAT) was used for detecting the presence of antibodies against Leptospira spp. in white-eared opossum, human, cattle and canine sera using a panel of 59 Leptospira strains that included the new isolate. The inclusion of the new strain in the MAT battery increased the MAT sensitivity for canine sera. These findings suggest that the white-eared opossum is an important reservoir of pathogenic Leptospira spp.

  18. Intrahepatic growth and maturation of Gnathostoma turgidum in the natural definitive opossum host, Didelphis virginiana.

    PubMed

    Díaz-Camacho, Sylvia Páz; Delgado-Vargas, Francisco; Willms, Kaethe; de la Cruz-Otero, María del Carmen; Guadalupe Rendón-Maldonado, José; Robert, Lilia; Antuna, Silvia; Nawa, Yukifumi

    2010-09-01

    Gnathostoma turgidum is a gastric nematode parasite of opossums found in the Americas. We recently found that G. turgidum juveniles appear in the liver of the opossums where they become mature adults and almost synchronously move to the stomach during certain months of the year, suggesting the importance of the liver for the growth and maturation of this species in the final hosts. In this study we attempted to detect G. turgidum larvae in the liver of opossums, Didelphis virginiana that are the natural final hosts. The results show that tiny (<3mm in length) third stage larvae (L3) appeared in the liver of opossums around November and December. Also in the liver, we found large L3 of up to about 10mm in length together with juveniles and mature adults from February to March. In spite of their length, large L3 have 4 rows of hooklets, and their gonads remained undeveloped. Morphological features of the small and large L3 of G. turgidum are described including scanning electron microscope images. The seasonal switching of the several growth stages of G. turgidum from small L3 to adult worms in the liver and eventual migration to the stomach in opossums suggests the unique feature of G. turgidum utilizing the liver as the maturation site.

  19. Experimental aerosol inoculation of Mycobacterium bovis in North American opossums (Didelphis virginiana).

    PubMed

    Fitzgerald, Scott D; Zwick, Laura S; Diegel, Kelly L; Berry, Dale E; Church, Steven V; Sikarskie, James G; Kaneene, John B; Reed, Willie M

    2003-04-01

    The goal of this study was to evaluate the susceptibility of North American opossums (Didelphis virginiana) to aerosol inoculation of Mycobacterium bovis at two dose levels in order to gain information on disease pathogenesis, fecal shedding of the organism, and the potential role that opossums play in the spread of this disease in nature. Six opossums received high dose (1 x 10(7) colony forming units (cfu) by aerosol inoculation, six opossums received low dose (1 x 10(3) cfu inoculation, and six opossums were sham-inoculated with sterile water and served as controls. Lungs were the most frequently infected tissues, with nine of 12 inoculated opossums positive for M. bovis on culture. Gross lesions consisted of multifocal pneumonia and enlarged lymph nodes. Microscopically, granulomatous pneumonia and granulomatous lymphadenitis associated with acid-fast bacilli were present in eight of 12 inoculated opossums. Fecal shedding of M. bovis was uncommon at both inoculation doses. While opossums were highly susceptible to aerosol inoculation of M. bovis, they did not become emaciated or develop widely disseminated lesions. From this study, opossums may transmit tuberculosis by aerosol infection to other opossums in close contact and serve as a source of infection to carnivores that feed upon them, however, transmission of the disease to large herbivores by fecal shedding or direct contact may be less likely.

  20. New Aspidoderidae species parasite of Didelphis aurita (Mammalia: Didelphidae): a light and scanning electron microscopy approach.

    PubMed

    Chagas-Moutinho, V A; Sant'anna, V; Oliveira-Menezes, A; De Souza, W

    2014-02-01

    Nematodes of the family Aspidoderidae (Nematoda: Heterakoidea) Skrjabin and Schikobalova, 1947, are widely distributed in the Americas. The family Aspidoderidae includes the subfamilies Aspidoderinae Skrjabin and Schikobalova, 1947, and Lauroiinae Skrjabin and Schikobalova, 1951. These two subfamilies are delineated by the presence or absence of cephalic cordons at the anterior region. The nematodes in the subfamily Aspidoderinae, which includes the genus AspidoderaRailliet and Henry, 1912, are represented by nematodes with anterior cephalic cordons at the anterior end. The nematodes of the genus AspidoderaRailliet and Henry, 1912, are found in the cecum and large intestine of mammals of the orders Edentata, Marsupialia and Rodentia. Species within this genus have many morphological similarities. The use of scanning electron microscopy allows the specific characterization of the species within this genus. In the present work, we describe a new species of Aspidodera parasite of the large intestine of Didelphis aurita (Mammalia: Didelphidae) Wied-Neuwied, 1826, collected from Cachoeiras de Macacu, Rio de Janeiro. The combination of light and scanning electron microscopy allowed us a detailed analysis of this nematode.

  1. Prevalence and risk factors associated with Sarcocystis neurona infections in opossums (Didelphis virginiana) from central California.

    PubMed

    Rejmanek, Daniel; Vanwormer, Elizabeth; Miller, Melissa A; Mazet, Jonna A K; Nichelason, Amy E; Melli, Ann C; Packham, Andrea E; Jessup, David A; Conrad, Patricia A

    2009-12-03

    Sarcocystis neurona, a protozoal parasite shed by opossums (Didelphis virginiana), has been shown to cause significant morbidity and mortality in horses, sea otters, and other marine mammals. Over the course of 3 years (fall 2005-summer 2008), opossums from central California were tested for infection with S. neurona. Of 288 opossums sampled, 17 (5.9%) were infected with S. neurona based on the molecular characterization of sporocysts from intestinal scrapings or feces. Risk factors evaluated for association with S. neurona infection in opossums included: age, sex, location, season, presence of pouch young in females, concomitant infection, and sampling method (live-trapped or traffic-killed). Multivariate logistic regression analysis identified that opossums in the Central Valley were 9 times more likely to be infected than those near the coast (p=0.009). Similarly, opossum infection was 5 times more likely to be detected during the reproductive season (March-July; p=0.013). This first investigation of S. neurona infection prevalence and associated risk factors in opossums in the western United States can be used to develop management strategies aimed at reducing the incidence of S. neurona infections in susceptible hosts, including horses and threatened California sea otters (Enhydra lutris neries).

  2. Molecular characterization of Sarcocystis neurona strains from opossums (Didelphis virginiana) and intermediate hosts from Central California.

    PubMed

    Rejmanek, Daniel; Miller, Melissa A; Grigg, Michael E; Crosbie, Paul R; Conrad, Patricia A

    2010-05-28

    Sarcocystis neurona is a significant cause of neurological disease in horses and other animals, including the threatened Southern sea otter (Enhydra lutris nereis). Opossums (Didelphis virginiana), the only known definitive hosts for S. neurona in North America, are an introduced species in California. S. neurona DNA isolated from sporocysts and/or infected tissues of 10 opossums, 6 horses, 1 cat, 23 Southern sea otters, and 1 harbor porpoise (Phocoena phocoena) with natural infections was analyzed based on 15 genetic markers, including the first internal transcribed spacer (ITS-1) region; the 25/396 marker; S. neurona surface antigen genes (snSAGs) 2, 3, and 4; and 10 different microsatellites. Based on phylogenetic analysis, most of the S. neurona strains segregated into three genetically distinct groups. Additionally, fifteen S. neurona samples from opossums and several intermediate hosts, including sea otters and horses, were found to be genetically identical across all 15 genetic markers, indicating that fatal encephalitis in Southern sea otters and equine protozoal myeloencephalitis (EPM) in horses is strongly linked to S. neurona sporocysts shed by opossums.

  3. FGF2, FGF3 and FGF4 expression pattern during molars odontogenesis in Didelphis albiventris.

    PubMed

    Dos Santos, Íria Gabriela Dias; Jorge, Erika Cristina; Copola, Aline Gonçalves Lio; Bertassoli, Bruno Machado; Goes, Alfredo Miranda de; Silva, Gerluza Aparecida Borges

    2017-03-01

    Odontogenesis is guided by a complex signaling cascade in which several molecules, including FGF2-4, ensure all dental groups development and specificity. Most of the data on odontogenesis derives from rodents, which does not have all dental groups. Didelphis albiventris is an opossum with the closest dentition to humans, and the main odontogenesis stages occur when the newborns are in the pouch. In this study, D. albiventris postnatals were used to characterize the main stages of their molars development; and also to establish FGF2, FGF3 and FGF4 expression pattern. D. albiventris postnatals were processed for histological and indirect immunoperoxidase analysis of the tooth germs. Our results revealed similar dental structures between D. albiventris and mice. However, FGF2, FGF3 and FGF4 expression patterns were observed in a larger number of dental structures, suggesting broader functions for these molecules in this opossum species. The knowledge of the signaling that determinates odontogenesis in an animal model with complete dentition may contribute to the development of therapies for the replacement of lost teeth in humans. This study may also contribute to the implementation of D. albiventris as model for Developmental Biology studies.

  4. Cone pigments in a North American marsupial, the opossum (Didelphis virginiana).

    PubMed

    Jacobs, Gerald H; Williams, Gary A

    2010-05-01

    Only two of the four cone opsin gene families found in vertebrates are represented in contemporary eutherian and marsupial species. Recent genetic studies of two species of South American marsupial detected the presence of representatives from two of the classes of cone opsin genes and the structures of these genes predicted cone pigments with respective peaks in the ultraviolet and long-wavelength portions of the spectrum. The Virginia opossum (Didelphis virginiana), a profoundly nocturnal animal, is the only marsupial species found in North America. The prospects for cone-based vision in this species were examined through recordings of the electroretinogram (ERG), a commonly examined retinal response to photic stimulation. Recorded under flickering-light conditions that elicit signals from cone photoreceptors, the spectral sensitivity of the opossum eye is well accounted for by contributions from the presence of a single cone pigment having peak absorption at 561-562 nm. A series of additional experiments that employed various chromatic adaptation paradigms were conducted in a search for possible contributions from a second (short-wavelength sensitive) cone pigment. We found no evidence that such a mechanism contributes to the ERG in this marsupial.

  5. Experimental infection of Didelphis marsupialis with vesicular stomatitis New Jersey virus.

    PubMed

    Trujillo, Carlos M; Rodriguez, Luis; Rodas, Juan D; Arboleda, John Jairo

    2010-01-01

    Although vesicular stomatitis has been present for many years in the Americas, many aspects of its natural history remain undefined. In this study, we challenged five adult Virginia opossums (Didelphis marsupialis) with vesicular stomatitis New Jersey serotype virus (VSNJV). Opossums had no detectable antibodies against VSNJV prior to being inoculated with 10(6.5) median tissue culture infective doses (TCID(50)) of VSNJV by two routes; intraepithelial/subepithelial (IE/SE) inoculation and scarification in the muzzle (SM). Clinical response was monitored daily and animals were tested for viral shedding. All infected animals developed vesicles and ulcers on the tongue and inflammation of the nasal alar folds. Virus was isolated from esophagus-pharynx, nasal, and from ocular swabs and lesions samples. The failure to detect viremia in these animals indicates that a source other than blood may be required for transmission to insect vectors. Our results suggest that D. marsupialis could play a role in the maintenance of VSNJV outside of domestic animal populations and could provide a model to study vesicular stomatitis virus pathogenesis.

  6. Coccidial dispersion across New World marsupials: Klossiella tejerai Scorza, Torrealba & Dagert, 1957 (Apicomplexa: Adeleorina) from the Brazilian common opossum Didelphis aurita (Wied-Neuwied) (Mammalia: Didelphimorphia).

    PubMed

    Dos Santos, Caroline Spitz; Berto, Bruno Pereira; do Bomfim Lopes, Bruno; Cordeiro, Matheus Dias; da Fonseca, Adivaldo Henrique; Filho, Walter Leira Teixeira; Lopes, Carlos Wilson Gomes

    2014-09-01

    Klossiella tejerai Scorza, Torrealba & Dagert, 1957 is a primitive coccidian parasite reported from the New World marsupials Didelphis marsupialis (Linnaeus) and Marmosa demerarae (Thomas). The current work describes K. tejerai from the Brazilian common opossum Didelphis aurita (Wied-Neuwied) in Southeastern Brazil, evidencing the coccidial dispersion across opossums of the same family. The sporocysts recovered from urine samples were ellipsoidal, 20.4 × 12.7 µm, with sporocyst residuum composed of scattered spherules and c.13 sporozoites per sporocyst, with refractile bodies and nucleus. Macrogametes, microgametes, sporonts, sporoblasts/sporocysts were identified within parasitophorous vacuoles of epithelial cells located near the renal corticomedullary junction. Didelphis marsupialis should not have transmitted K. tejerai to D. aurita because they are not sympatric; however M. demerarae is sympatric with D. marsupialis and D. aurita. Therefore, D. aurita becomes the third host species for K. tejerai in South America.

  7. Occurrence of gastrointestinal protozoa in Didelphis albiventris (opossum) in the central region of Rio Grande do Sul state.

    PubMed

    Zanette, Régis A; da Silva, Aleksandro S; Lunardi, Fabiane; Santurio, Janio M; Monteiro, Silvia G

    2008-06-01

    The aim of this study was to evaluate the parasitism by gastrointestinal protozoa in Didelphis albiventris (opossum) in the central region of Rio Grande do Sul state. Fecal samples from six free living opossums were collected for research of parasites. Samples were analyzed by the centrifugal-flotation method with zinc sulfate and parasites were identified microscopically based on (oo)cyst size and morphology. Cysts of Giardia sp. and oocysts of Cryptosporidium sp. and Eimeria sp. were observed in four of the six opossums. All four infected marsupials showed mild infection by protozoa. This is the first report of Giardia sp. in D. albiventris.

  8. Prevalence of Sarcocystis species sporocysts in Northern Virginia opossums (Didelphis virginiana).

    PubMed

    Elsheikha, Hany M; Murphy, Alice J; Mansfield, Linda S

    2004-08-01

    A total of 206 Virginia opossums ( Didelphis virginiana) collected from the mid-Michigan region, United States, during a period extending from 1996 to 2002 were sampled for the presence of Sarcocystis spp sporocysts. All isolates were phenotypically identified as Sarcocystis spp and genotyped to the species level by PCR-based techniques. The overall prevalence of Sarcocystis spp in opossums was 18% (37/206). The prevalence of Sarcocystis spp differed significantly with age ( P<0.001) and adult opossums were more commonly infected (14.6%; 30/206) than juveniles (3.4%; 7/206). No significant difference in the prevalence of Sarcocystis spp infection was observed between male and female ( P<0.15). The highest prevalence was recorded during summer (9.2%; 19/206). PCR-RFLP analyses demonstrated the majority of Sarcocystis isolates to be S. neurona, with some animals co-infected with sporocysts of S. falcatula. Out of the 37 Sarcocystis-infected opossums, 23 (62%) had sporocysts of S. neurona only, four (11%) had sporocysts of S. falcatula only, and eight (22%) had a mixture of S. neurona and S. falcatula sporocysts. These findings indicate that mixed Sarcocystis infections in opossums are common. The propensity for Sarcocystis spp to co-exist in the opossum gut enhances dissemination and environmental contamination with these coccidia. Additionally, this increases the chance for sexual recombination between Sarcocystis spp, given the proclivity of these species to reproduce sexually at high numbers in the intestinal cells of their definitive host.

  9. Evaluation of a rapid immunochromatographic dipstick test for detection of antibodies to Trypanosoma cruzi in dogs experimentally infected with isolates obtained from opossums (Didelphis virginiana), armadillos (Dasypus novemcinctus), and dogs (Canis familiaris) from the United States.

    PubMed

    Rosypal, Alexa C; Hill, Roderick; Lewis, Samantha; Barr, Stephen C; Valadas, Samantha; Gennari, Solange Maria; Lindsay, David S

    2011-02-01

    Dogs are reservoir hosts for Trypanosoma cruzi , the causative agent of American trypanosomiasis. A rapid immunochromatographic dipstick test (ICT) is available commercially for canine serological testing. The ICT was developed with the use of sera from South American dogs, but it is not routinely used in the United States. We evaluated the utility of the ICT in detecting anti-T. cruzi antibodies in dogs from the United States. Dogs (N  =  64) were experimentally infected with United States' isolates of T. cruzi from an opossum (Didelphis virginiana), an armadillo (Dasypus novemcinctus), and a domestic dog (Canis familiaris), and were tested after experimental infection. Sera from uninfected United States dogs (n  =  79; hemaculture negative) were used as negative controls. In a blind study, sera were tested by the ICT and compared to the indirect immunofluorescent antibody test with the use of Brazil-strain epimastigotes as antigen. The sensitivity of the ICT was 91% and the specificity was 98% in dogs experimentally infected with United States isolates. Our study indicates that the ICT could be a useful screening tool for serological surveillance of canine T. cruzi exposure in the United States.

  10. Surveillance and movements of Virginia opossum (Didelphis virginiana) in the bovine tuberculosis region of Michigan.

    PubMed

    Walter, W D; Fischer, J W; Anderson, C W; Marks, D R; Deliberto, T; Robbe-Austerman, S; Vercauteren, K C

    2013-07-01

    Wildlife reservoir hosts of bovine tuberculosis (bTB) include Eurasian badgers (Meles meles) and brushtail possum (Trichosurus vulpecula) in the UK and New Zealand, respectively. Similar species warrant further investigation in the northern lower peninsula of Michigan, USA due to the continued presence of bTB on cattle farms. Most research in Michigan, USA has focused on interactions between white-tailed deer (Odocoileus virginianus) and cattle (Bos taurus) for the transmission of the infectious agent of bTB, Mycobacterium bovis, due to high deer densities and feeding practices. However, limited data are available on medium-sized mammals such as Virginia opossum (Didelphis virginiana; hereafter referred to as opossum) and their movements and home range in Michigan near cattle farms. We conducted surveillance of medium-sized mammals on previously depopulated cattle farms for presence of M. bovis infections and equipped opossum with Global Positioning System (GPS) technology to assess potential differences in home range between farms inside and outside the bTB core area that has had cattle test positive for M. bovis. On farms inside the bTB core area, prevalence in opossum was comparable [6%, 95% confidence interval (CI) 2.0-11.0] to prevalence in raccoon (Procyon lotor; 4%, 95% CI 1.0-9.0, P=0.439) whereas only a single opossum tested positive for M. bovis on farms outside the bTB core area. The prevalence in opossum occupying farms that had cattle test positive for M. bovis was higher (6.4%) than for opossum occupying farms that never had cattle test positive for M. bovis (0.9%, P=0.01). Mean size of home range for 50% and 95% estimates were similar by sex (P=0.791) both inside or outside the bTB core area (P=0.218). Although surveillance efforts and home range were not assessed on the same farms, opossum use of farms near structures was apparent as was selection for farms over surrounding forested habitats. The use of farms, stored feed, and structures by opossum

  11. Blind Ambition

    ERIC Educational Resources Information Center

    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…

  12. Blindness Clues

    ERIC Educational Resources Information Center

    Science Teacher, 2005

    2005-01-01

    Age-related macular degeneration is the leading cause of blindness in older adults, yet researchers are still in the dark about many of the factors that cause this incurable disease. But new insight from University of Florida (UF) and German researchers about a genetic link between rhesus monkeys with macular degeneration and humans could unlock…

  13. Lack of Sarcocystis neurona antibody response in Virginia opossums (Didelphis virginiana) fed Sarcocystis neurona-infected muscle tissue.

    PubMed

    Cheadle, M A; Lindsay, D S; Greiner, E C

    2006-06-01

    Serum was collected from laboratory-reared Virginia opossums (Didelphis virginiana) to determine whether experimentally infected opossums shedding Sarcocystis neurona sporocysts develop serum antibodies to S. neurona merozoite antigens. Three opossums were fed muscles from nine-banded armadillos (Dasypus novemcinctus), and 5 were fed muscles from striped skunks (Mephitis mephitis). Serum was also collected from 26 automobile-killed opossums to determine whether antibodies to S. neurona were present in these opossums. Serum was analyzed using the S. neurona direct agglutination test (SAT). The SAT was modified for use with a filter paper collection system. Antibodies to S. neurona were not detected in any of the serum samples from opossums, indicating that infection in the opossum is localized in the small intestine. Antibodies to S. neurona were detected in filter-paper-processed serum samples from 2 armadillos naturally infected with S. neurona.

  14. Acute Blindness.

    PubMed

    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.

  15. Congenitally Blind Counselor, Adventitiously Blind Client.

    ERIC Educational Resources Information Center

    Roberts, A. H.

    1994-01-01

    A counselor blind from birth describes personal difficulties in fully understanding the experience of clients who are adventitiously blind. Congenitally blind counselors are urged to recognize that adaptive methods cannot compensate for the panoramic view of the environment provided by vision and that recently blinded individuals need to deal with…

  16. Inhibition of the hemorrhagic and proteolytic activities of Lansberg's hognose pit viper (Porthidium lansbergii hutmanni) venom by opossum (Didelphis marsupialis) serum: isolation of Didelphis marsupialis 0.15Dm fraction on DEAE-cellulose chromatography.

    PubMed

    Pineda, María E; Girón, María E; Estrella, Amalid; Sánchez, Elda E; Aguilar, Irma; Fernandez, Irma; Vargas, Alba M; Scannone, Héctor; Rodríguez-Acosta, Alexis

    2008-01-01

    Earlier studies have revealed the ability of sera from several mammals to neutralize the toxic effects of snake venom. The Venezuelan opossum (Didelphis marsupialis) is one that has been found to inhibit hemorrhagic and proteolytic activities of venoms from many species of snakes. In this article it is shown that the opossum sera and its 0.15DM fraction were able to completely neutralize both hemorrhagic and hydrolysis (proteolysis) of casein effects induced by venom of the Lansberg's hognose pit viper (Porthidium lansbergii hutmanni). We have used DEAE-cellulose ion exchange chromatography to collect protein fractions from D. marsupialis sera which were able to defend mice from the lethal effects of P.l. hutmanni venom. The fractions separated were homogeneous by conventional electrophoresis using SDS-PAGE. The protein bands obtained contained molecular weights of approximately 6 to 220 kDa. These results revealed the presence of proteases inhibitors in the opossum sera fractions and the inhibition of venom activity by opossum sera suggesting a reciprocal adaptation at the molecular level.

  17. Repetition blindness is orientation blind.

    PubMed

    Corballis, Michael C; Armstrong, Cole

    2007-03-01

    In identifying rapid sequences of three letters, subjects were worse at identifying the first and third letters when they were the same than when they were different, indicating repetition blindness (RB). This effect occurred regardless of the angular orientations of the letters, but was more pronounced when the orientations of the repeated letters were different than when they were the same. In a second experiment, RB was also evident when the first and third letters were lowercase bs or ds, presented upright or inverted, even though they are differently named when inverted (q and p, respectively). Conversely, a third experiment showed that RB occurred when the letters had the same names but were repeated in different case. These results suggest that the early extraction of letter shape is independent of its orientation and left-right sense, and that RB can occur at the levels of both shape and name.

  18. Experimental Aerosol Inoculation and Investigation of Potential Lateral Transmission of Mycobacterium bovis in Virginia Opossum (Didelphis virginiana).

    PubMed

    Fenton, Karla A; Fitzgerald, Scott D; Bolin, Steve; Kaneene, John; Sikarskie, James; Greenwald, Rena; Lyashchenko, Konstantin

    2012-01-01

    An endemic focus of Mycobacterium bovis (M. bovis) infection in the state of Michigan has contributed to a regional persistence in the animal population. The objective of this study was to determine if Virginia opossums (Didelphis virginiana) contribute to disease persistence by experimentally assessing intraspecies lateral transmission. One wild caught pregnant female opossum bearing 11 joeys (young opossum) and one age-matched joey were obtained for the study. Four joeys were aerosol inoculated with M. bovis (inoculated), four joeys were noninoculated (exposed), and four joeys plus the dam were controls. Four replicate groups of one inoculated and one exposed joey were housed together for 45 days commencing 7 days after experimental inoculation. At day 84 opossums were sacrificed. All four inoculated opossums had a positive test band via rapid test, culture positive, and gross/histologic lesions consistent with caseogranulomatous pneumonia. The exposed and control groups were unremarkable on gross, histology, rapid test, and culture. In conclusion, M. bovis infection within the inoculated opossums was confirmed by gross pathology, histopathology, bacterial culture, and antibody tests. However, M. bovis was not detected in the control and exposed opossums. There was no appreciable lateral transmission of M. bovis after aerosol inoculation and 45 days of cohabitation between infected and uninfected opossums.

  19. Prevalence of agglutinating antibodies to Sarcocystis neurona in skunks (Mephitis Mephitis), raccoons (Procyon lotor), and opossums (Didelphis Virginiana) from Connecticut.

    PubMed

    Mitchell, Sheila M; Richardson, Dennis J; Cheadle, M Andy; Zajac, Anne M; Lindsay, David S

    2002-10-01

    Equine protozoal myeloencephalitis is the most important protozoan disease of horses in North America and is usually caused by Sarcocystis neurona. Natural cases of encephalitis caused by S. neurona have been reported in skunks (Mephitis mephitis) and raccoons (Procyon lotor). Opossums (Didelphis spp.) are the only known definitive host. Sera from 24 striped skunks, 12 raccoons, and 7 opossums (D. virginiana) from Connecticut were examined for agglutinating antibodies to S. neurona using the S. neurona agglutination test (SAT) employing formalin-fixed merozoites as antigen. The SAT was validated for skunk sera using pre- and postinfection serum samples from 2 experimentally infected skunks. Of the 24 (46%) skunks 11 were positive, and all 12 raccoons were positive for S. neurona antibodies. None of the 7 opossums was positive for antibodies to S. neurona. These results suggest that exposure to sporocysts of S. neurona by intermediate hosts is high in Connecticut. The absence of antibodies in opossums collected from the same areas is most likely because of the absence of systemic infection in the definitive host.

  20. Morphologic characterization and distribution of endocrine cells in the large intestine of the opossum Didelphis aurita (Wied-Neuwied, 1826).

    PubMed

    Dos Santos, Daiane Cristina Marques; Cupertino, Marli do Carmo; Novaes, Rômulo Dias; Soares, Ítalo Augusto da Costa; Fonseca, Cláudio César; da Matta, Sérgio Luis Pinto; Sartori, Sirlene Souza Rodrigues

    2013-10-01

    This study was designed to investigate the morphology and distribution of argyrophil, argentaffins, and insulin-immunoreactive endocrine cells in the large intestine of the opossum Didelphis aurita. Fragments of the large intestine of 10 male specimens of the opossum D. aurita were collected, processed, and submitted for histochemistry, immunohistochemistry, and scanning electron microscopy. The tunics of the large intestine of D. aurita presented morphological characteristics that have already been described for eutherian mammals. The morphometric data showed that the inner circular layer of all portions and regions analyzed is thicker relative to the longitudinal layer, and these layers in the rectum are thicker compared to the cecum and ascending colon. The majority of mucus-secreting cells have acid and neutral mucins, suggesting that the production of mucus is mixed. The number of these cells increases in the region of the cecum toward the rectum. Important findings include the occurrence of argyrophil, argentaffins, and insulin-immunoreactive endocrine cells in all segments of the large intestine of the opossum (D. aurita). To the best of our knowledge, this is the first report about the presence of insulin-immunoreactive endocrine cells in the large intestine of the opossum (D. aurita).

  1. Genetically different isolates of Trypanosoma cruzi elicit different infection dynamics in raccoons (Procyon lotor) and Virginia opossums (Didelphis virginiana).

    PubMed

    Roellig, Dawn M; Ellis, Angela E; Yabsley, Michael J

    2009-12-01

    Trypanosoma cruzi is a genetically and biologically diverse species. In the current study we determined T. cruzi infection dynamics in two common North American reservoirs, Virginia opossums (Didelphis virginiana) and raccoons (Procyon lotor). Based on previous molecular and culture data from naturally-exposed animals, we hypothesised that raccoons would have a longer patent period than opossums, and raccoons would be competent reservoirs for both genotypes T. cruzi I (TcI) and TcIIa, while opossums would only serve as hosts for TcI. Individuals (n=2 or 3) of each species were inoculated with 1x10(6) culture-derived T. cruzi trypomastigotes of TcIIa (North American (NA) - raccoon), TcI (NA - opossum), TcIIb (South American - human), or both TcI and TcIIa. Parasitemias in opossums gradually increased and declined rapidly, whereas parasitemias peaked sooner in raccoons and they maintained relatively high parasitemia for 5weeks. Raccoons became infected with all three T. cruzi strains, while opossums only became infected with TcI and TcIIb. Although opossums were susceptible to TcIIb, infection dynamics were dramatically different compared with TcI. Opossums inoculated with TcIIb seroconverted, but parasitemia duration was short and only detectable by PCR. In addition, raccoons seroconverted sooner (3-7days post inoculation) than opossums (10days post inoculation). These data suggest that infection dynamics of various T. cruzi strains can differ considerably in different wildlife hosts.

  2. Experimental Aerosol Inoculation and Investigation of Potential Lateral Transmission of Mycobacterium bovis in Virginia Opossum (Didelphis virginiana)

    PubMed Central

    Fenton, Karla A.; Fitzgerald, Scott D.; Bolin, Steve; Kaneene, John; Sikarskie, James; Greenwald, Rena; Lyashchenko, Konstantin

    2012-01-01

    An endemic focus of Mycobacterium bovis (M. bovis) infection in the state of Michigan has contributed to a regional persistence in the animal population. The objective of this study was to determine if Virginia opossums (Didelphis virginiana) contribute to disease persistence by experimentally assessing intraspecies lateral transmission. One wild caught pregnant female opossum bearing 11 joeys (young opossum) and one age-matched joey were obtained for the study. Four joeys were aerosol inoculated with M. bovis (inoculated), four joeys were noninoculated (exposed), and four joeys plus the dam were controls. Four replicate groups of one inoculated and one exposed joey were housed together for 45 days commencing 7 days after experimental inoculation. At day 84 opossums were sacrificed. All four inoculated opossums had a positive test band via rapid test, culture positive, and gross/histologic lesions consistent with caseogranulomatous pneumonia. The exposed and control groups were unremarkable on gross, histology, rapid test, and culture. In conclusion, M. bovis infection within the inoculated opossums was confirmed by gross pathology, histopathology, bacterial culture, and antibody tests. However, M. bovis was not detected in the control and exposed opossums. There was no appreciable lateral transmission of M. bovis after aerosol inoculation and 45 days of cohabitation between infected and uninfected opossums. PMID:22701815

  3. Endogenous Life Cycle of Eimeria marmosopos (Apicomplexa: Eimeriidae) from the Opossum, Didelphis marsupialis (Didelphimorphia: Didelphidae) in Costa Rica.

    PubMed

    Chinchilla, Misael; Valerio, Idalia; Duszynski, Donald

    2015-08-01

    The endogenous life cycle of Eimeria marmosopos was studied in experimentally infected young opossums, Didelphis marsupialis . All the endogenous stages were located in the epithelial cells of villi in the small intestine. Giemsa-stained mucosal scrapings and histological sections were studied for the diagnosis of all the life cycle stages. Eimeria marmosopos has 3 generations of meronts (M) that differ by size, shape, and number of merozoites (m), which also differ in their size, shape, and location of their nuclei within the cytoplasm of the meronts. The 3 meront types, M(1)-M(3), respectively, had 8-15 (m(1)), 4-9 (m(2)), and 22-30 (m(3)) merozoites. Macrogametocytes and microgametocytes, as well as macrogametes and microgametes, completed the sexual cycle, finishing with the formation of unsporulated oocysts. This parasite's endogenous development produced severe intestinal lesions in experimentally infected opossums. There are 56 Eimeria species known from all marsupials worldwide, but this is the first complete life cycle in which both the asexual and sexual stages have been documented.

  4. Anomalous colour in Neotropical mammals: a review with new records for Didelphis sp. (Didelphidae, Didelphimorphia) and Arctocephalus australis (Otariidae, Carnivora).

    PubMed

    Abreu, M S L; Machado, R; Barbieri, F; Freitas, N S; Oliveira, L R

    2013-02-01

    Anomalous colourations occur in many tropical vertebrates. However, they are considered rare in wild populations, with very few records for the majority of animal taxa. We report two new cases of anomalous colouration in mammals. Additionally, we compiled all published cases about anomalous pigmentation registered in Neotropical mammals, throughout a comprehensive review of peer reviewed articles between 1950 and 2010. Every record was classified as albinism, leucism, piebaldism or eventually as undetermined pigmentation. As results, we report the new record of a leucistic specimen of opossum (Didelphis sp.) in southern Brazil, as well as a specimen of South American fur seal (Arctocephalus australis) with piebaldism in Uruguay. We also found 31 scientific articles resulting in 23 records of albinism, 12 of leucism, 71 of piebaldism and 92 records classified as undetermined pigmentation. Anomalous colouration is apparently rare in small terrestrial mammals, but it is much more common in cetaceans and michrochiropterans. Out of these 198 records, 149 occurred in cetaceans and 30 in bats. The results related to cetaceans suggest that males and females with anomolous pigmentation are reproductively successful and as a consequence their frequencies are becoming higher in natural populations. In bats, this result can be related to the fact these animals orient themselves primarily through echolocation, and their refuges provide protection against light and predation. It is possible that anomalous colouration occurs more frequently in other Neotropical mammal orders, which were not formally reported. Therefore, we encourage researchers to publish these events in order to better understand this phenomenon that has a significant influence on animal survival.

  5. Color Blindness Simulations

    MedlinePlus

    ... Coordinator Color blindness Simulations Normal Color Vision Deuteranopia Color blindness marked by confusion of purplish red and green Tritanopia A dichromatism in which the spectrum is seen in tones of red and green. ...

  6. Blind Quantum Signature with Blind Quantum Computation

    NASA Astrophysics Data System (ADS)

    Li, Wei; Shi, Ronghua; Guo, Ying

    2017-04-01

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

  7. Blind Quantum Signature with Blind Quantum Computation

    NASA Astrophysics Data System (ADS)

    Li, Wei; Shi, Ronghua; Guo, Ying

    2016-12-01

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

  8. Blindness and anorexia nervosa.

    PubMed

    McFarlane, A C

    1989-06-01

    Two cases of anorexia nervosa in blind patients are reported. They demonstrate that blind children experience many developmental problems which are thought to be important in the etiology of anorexia nervosa. Similarly, blind children are unusually susceptible to misperceive their body size and weight. The apparent absence of a strong association between congenital blindness and anorexia nervosa challenges the presumed aetiological link between disturbed body image and identity diffusion, and anorexia nervosa.

  9. Sarcocystis neurona infections in raccoons (Procyon lotor): evidence for natural infection with sarcocysts, transmission of infection to opossums (Didelphis virginiana), and experimental induction of neurologic disease in raccoons.

    PubMed

    Dubey, J P; Saville, W J; Stanek, J F; Lindsay, D S; Rosenthal, B M; Oglesbee, M J; Rosypal, A C; Njoku, C J; Stich, R W; Kwok, O C; Shen, S K; Hamir, A N; Reed, S M

    2001-10-24

    Equine protozoal myeloencephalitis (EPM) is a serious neurologic disease of horses in the Americas and Sarcocystis neurona is the most common etiologic agent. The distribution of S. neurona infections follows the geographical distributions of its definitive hosts, opossums (Didelphis virginiana, Didelphis albiventris). Recently, cats and skunks were reported as experimental and armadillos as natural intermediate hosts of S. neurona. In the present report, raccoons (Procyon lotor) were identified as a natural intermediate host of S. neurona. Two laboratory-raised opossums were found to shed S. neurona-like sporocysts after ingesting tongues of naturally-infected raccoons. Interferon-gamma gene knockout (KO) mice fed raccoon-opossum-derived sporocysts developed neurologic signs. S. neurona was identified immunohistochemically in tissues of KO mice fed sporocysts and the parasite was isolated in cell cultures inoculated with infected KO mouse tissues. The DNA obtained from the tongue of a naturally-infected raccoon, brains of KO mice that had neurological signs, and from the organisms recovered in cell cultures inoculated with brains of neurologic KO mice, corresponded to that of S. neurona. Two raccoons fed mature S. neurona sarcocysts did not shed sporocysts in their feces, indicating raccoons are not likely to be its definitive host. Two raccoons fed sporocysts from opossum feces developed clinical illness and S. neurona-associated encephalomyelitis was found in raccoons killed 14 and 22 days after feeding sporocysts; schizonts and merozoites were seen in encephalitic lesions.

  10. Serological evidence of exposure to tick-borne agents in opossums (Didelphis spp.) in the state of São Paulo, Brazil.

    PubMed

    Melo, Andréia Lima Tomé; Aguiar, Daniel Moura de; Spolidorio, Mariana Granziera; Yoshinari, Natalino Hajime; Matushima, Eliana Reiko; Labruna, Marcelo Bahia; Horta, Mauricio Claudio

    2016-06-07

    This work involved a serological investigation of tick-borne pathogens in opossums in eight municipalities of the state of São Paulo, Brazil. Serum samples from 109 opossums (91 Didelphis aurita and 18 Didelphis albiventris) were tested to detect antibodies to Rickettsia rickettsii (Taiaçu strain, 1:64 cut-off) and Ehrlichia canis (São Paulo strain, 1:40 cut-off), by indirect immunofluorescence assay (IFA); and against Borrelia burgdorferi (strain G39/40) by enzyme-linked immunosorbent assay (ELISA). The presence of antibodies to anti-R. rickettsii, anti-E. canis and anti-B. burgdorferi was detected in 32 (29.35%), 16 (14.67%) and 30 (27.52%) opossums, respectively. Opossum endpoint titers ranged from 64 to 1,024 for R. rickettsii, from 40 to 160 for E. canis, and from 400 to >51,200 for B. burgdorferi. These serological results suggest that opossums have been exposed to Rickettsia spp., Ehrlichia spp., and B. burgdorferi-related agents in the state of São Paulo. Our study underscores the need for further research about these agents in this study area, in view of the occurrence of Spotted Fever and Baggio-Yoshinari Syndrome disease in humans in the state of São Paulo, Brazil.

  11. Global data on blindness.

    PubMed Central

    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

  12. Refractive error blindness.

    PubMed Central

    Dandona, R.; Dandona, L.

    2001-01-01

    Recent data suggest that a large number of people are blind in different parts of the world due to high refractive error because they are not using appropriate refractive correction. Refractive error as a cause of blindness has been recognized only recently with the increasing use of presenting visual acuity for defining blindness. In addition to blindness due to naturally occurring high refractive error, inadequate refractive correction of aphakia after cataract surgery is also a significant cause of blindness in developing countries. Blindness due to refractive error in any population suggests that eye care services in general in that population are inadequate since treatment of refractive error is perhaps the simplest and most effective form of eye care. Strategies such as vision screening programmes need to be implemented on a large scale to detect individuals suffering from refractive error blindness. Sufficient numbers of personnel to perform reasonable quality refraction need to be trained in developing countries. Also adequate infrastructure has to be developed in underserved areas of the world to facilitate the logistics of providing affordable reasonable-quality spectacles to individuals suffering from refractive error blindness. Long-term success in reducing refractive error blindness worldwide will require attention to these issues within the context of comprehensive approaches to reduce all causes of avoidable blindness. PMID:11285669

  13. Leishmania chagasi in Opossums (Didelphis albiventris) in an Urban Area Endemic for Visceral Leishmaniasis, Campo Grande, Mato Grosso do Sul, Brazil

    PubMed Central

    Humberg, Roberta M. P.; Oshiro, Elisa T.; Cruz, Maria do Socorro Pires e; Ribolla, Paulo E. M.; Alonso, Diego P.; Ferreira, Alda M. T.; Bonamigo, Raquel A.; Tasso, Norton; de Oliveira, Alessandra Gutierrez

    2012-01-01

    We investigated the occurrence of Leishmania infantum chagasi in Didelphis albiventris opossums at a wild animal rehabilitation center in the city of Campo Grande, Brazil. A total of 54 opossums were tested for L. i. chagasi infection in peripheral blood and bone marrow samples. The samples were analyzed by direct examination, culturing in a specific medium, and polymerase chain reaction–restriction fragment length polymorphism. Leishmania i. chagasi DNA was detected by polymerase chain reaction–restriction fragment length polymorphism in 11 (20.37%) animals. A total of 81.81% of positive opossums were captured in areas of known visceral leishmaniasis transmission. These results suggest a role for D. albiventris in the urban transmission of visceral leishmaniasis. PMID:22802435

  14. Blindness and Yoga

    ERIC Educational Resources Information Center

    Heyes, Anthony David

    1974-01-01

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

  15. "Color-Blind" Racism.

    ERIC Educational Resources Information Center

    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…

  16. Blindness after intranasal ethmoidectomy.

    PubMed

    Sözeri, B; Ataman, M; Gürsel, B

    1993-06-01

    Orbital haemorrhage is an unusual and frustrating complication of ethmoid surgery. A case of reversible blindness which was due to intra-operative orbital haemorrhage occurring after intranasal ethmoidectomy is presented. Prevention and management of this kind of blindness can be reversed, if treated aggressively.

  17. Change blindness images.

    PubMed

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

    2013-11-01

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

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

    ERIC Educational Resources Information Center

    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…

  19. How "Blind" Are Double-Blind Studies?

    ERIC Educational Resources Information Center

    Margraf, Jurgen; And Others

    1991-01-01

    Compared alprazolam, imipramine, and placebo in the treatment of panic disorder patients (n=59) to investigate concerns about the internal validity of the double-blind design. Found that the great majority of patients and physicians were able to rate accurately whether active drug or placebo had been given and physicians could distinguish between…

  20. Leading Causes of Blindness

    MedlinePlus

    ... Cataract. Photo courtesy of National Eye Institute, NIH Cataracts Cataracts are a clouding of the lenses in your ... older people. More than 22 million Americans have cataracts. They are the leading cause of blindness in ...

  1. Vision - night blindness

    MedlinePlus

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

  2. Epidemiology of blindness in Nepal*

    PubMed Central

    Brilliant, L. B.; Pokhrel, R. P.; Grasset, N. C.; Lepkowski, J. M.; Kolstad, A.; Hawks, W.; Pararajasegaram, R.; Brilliant, G. E.; Gilbert, S.; Shrestha, S. R.; Kuo, J.

    1985-01-01

    This report presents the major findings of the Nepal Blindness Survey, the first nationwide epidemiological survey of blindness, which was conducted in 1979-80. The survey was designed to gather data that could be used to estimate the prevalence and causes of blindness in the country. Ancillary studies were conducted to obtain information on socioeconomic correlates and other risk factors of blinding conditions and patterns of health care utilization. The nationwide blindness prevalence rate is 0.84%. Cataract is the leading cause of blindness, accounting for over 80% of all avoidable blindness. Trachoma is the most prevalent blinding condition, affecting 6.5% of the population. Very few cases of childhood blindness were detected. The implications of the survey findings for programme planning, health manpower development, and health education are discussed. PMID:3874717

  3. Optimal Blind Quantum Computation

    NASA Astrophysics Data System (ADS)

    Mantri, Atul; Pérez-Delgado, Carlos A.; Fitzsimons, Joseph F.

    2013-12-01

    Blind quantum computation allows a client with limited quantum capabilities to interact with a remote quantum computer to perform an arbitrary quantum computation, while keeping the description of that computation hidden from the remote quantum computer. While a number of protocols have been proposed in recent years, little is currently understood about the resources necessary to accomplish the task. Here, we present general techniques for upper and lower bounding the quantum communication necessary to perform blind quantum computation, and use these techniques to establish concrete bounds for common choices of the client’s quantum capabilities. Our results show that the universal blind quantum computation protocol of Broadbent, Fitzsimons, and Kashefi, comes within a factor of (8)/(3) of optimal when the client is restricted to preparing single qubits. However, we describe a generalization of this protocol which requires exponentially less quantum communication when the client has a more sophisticated device.

  4. Meningeal carcinomatosis and blindness

    PubMed Central

    Altrocchi, Paul H.; Eckman, Paul B.

    1973-01-01

    The clinical syndrome of meningeal carcinomatosis includes headache, dementia, radiculopathy, and cranial nerve palsies. Blindness may be the first, or most prominent, symptom. When blindness occurs in adult life, meningeal carcinomatosis should be included in the differential diagnosis, even in the absence of other symptoms and in the absence of known malignancy. Although all pathophysiological mechanisms of the blindness in meningeal carcinomatosis have not yet been elucidated, optic nerve involvement by meningeal tumour-cuffing, by chronic papilloedema, and by direct tumour infiltration represent the likeliest causes. In the neuropathological analysis of such cases, the importance of analysing the intra-orbital portion of the optic nerves, in addition to the portions of the optic nerve and chiasm usually examined at routine necropsy, is emphasized. A case is described to illustrate this point, with the only pathological abnormality in the optic nerves being found within 6 mm of the retina. Images PMID:4708455

  5. Blinded by headlights.

    PubMed

    Stevanovski, Biljana; Oriet, Chris; Jolicoeur, Pierre

    2002-06-01

    Target identification is impaired when targets are presented during the planning or execution of a compatible response (e.g., right-pointing arrow during a right keypress) relative to an incompatible response (Müsseler & Hommel, 1997 a, b). Examinations of this blindness to response-compatible stimuli have typically used arrowheads as targets ("<" and ">"). The importance of the target symbol was examined by manipulating subjects' interpretation of that symbol (i.e., ">" interpreted as a right-pointing arrow or as a headlight shining to the left). Targets were presented at varying times during the planning or execution of a response in order to examine the time-course of the effect. Results showed that the interpretation, and not the physical identity, of the target was important for the blindness effect. Although the blindness effect was largest during the planning and execution of a response, it was not always confined to that temporal interval.

  6. Prevalence of antibodies to Trypanosoma cruzi, Toxoplasma gondii, Encephalitozoon cuniculi, Sarcocystis neurona, Besnoitia darlingi, and Neospora caninum in North American opossums, Didelphis virginiana, from southern Louisiana.

    PubMed

    Houk, Alice E; Goodwin, David G; Zajac, Anne M; Barr, Stephen C; Dubey, J P; Lindsay, David S

    2010-12-01

    We examined the prevalence of antibodies to zoonotic protozoan parasites ( Trypanosoma cruzi, Toxoplasma gondii, and Encephalitozoon cuniculi) and protozoans of veterinary importance ( Neospora caninum, Sarcocystis neurona, and Besnoitia darlingi) in a population of North American opossums ( Didelphis virginiana) from Louisiana. Samples from 30 opossums were collected as part of a survey for T. cruzi in Louisiana. Frozen sera from these 30 opossums were examined using an indirect immunofluorescent antibody test (IFAT) against in vitro-produced antigenic stages of these protozoans. Additionally, 24 of the 30 samples were examined using hemoculture, and all 30 were examined in the modified direct agglutination test (MAT) for antibodies to To. gondii. The prevalences of reactive IFAT samples were as follows: 60% for T. cruzi, 27% for To. gondii, 23% for E. cuniculi, 17% for S. neurona, 47% for B. darlingi, and 0% for N. caninum. Hemoculture revealed that 16 (67%) of 24 samples were positive for T. cruzi, compared to 18 of 30 (60%) by IFAT. The sensitivity and specificity for the IFAT compared to hemoculture was 100% for each. The modified direct agglutination test revealed that 9 (30%) of the 30 samples from opossums had antibodies to To. gondii , compared to 8 (27%) using the IFAT. The sensitivity and specificity of the IFAT compared to the MAT was 100% and 72%, respectively.

  7. Quantification of endocrine cells and ultrastructural study of insulin granules in the large intestine of opossum Didelphis aurita (Wied-Neuwied, 1826).

    PubMed

    dos Santos, Daiane Cristina Marques; Cupertino, Marli do Carmo; Fialho, Maria do Carmo Queiroz; Barbosa, Alfredo Jose Afonso; Fonseca, Cláudio Cesar; Sartori, Sirlene Souza Rodrigues; da Matta, Sérgio Luis Pinto

    2014-02-01

    This study aimed to investigate the distribution of argyrophil, argentaffin, and insulin-immunoreactive endocrine cells in the large intestine of opossums (Didelphis aurita) and to describe the ultrastructure of the secretory granules of insulin-immunoreactive endocrine cells. Fragments of the large intestine of 10 male specimens of D. aurita were collected, processed, and subjected to staining, immunohistochemistry, and transmission electron microscopy. The argyrophil, the argentaffin, and the insulin-immunoreactive endocrine cells were sparsely distributed in the intestinal glands of the mucous layer, among other cell types of the epithelium in all regions studied. Proportionally, the argyrophil, the argentaffin, and the insulin-immunoreactive endocrine cells represented 62.75%, 36.26%, and 0.99% of the total determined endocrine cells of the large intestine, respectively. Quantitatively, there was no difference between the argyrophil and the argentaffin endocrine cells, whereas insulin-immunoreactive endocrine cells were less numerous. The insulin-immunoreactive endocrine cells were elongated or pyramidal, with rounded nuclei of irregularly contoured, and large amounts of secretory granules distributed throughout the cytoplasm. The granules have different sizes and electron densities and are classified as immature and mature, with the mature granules in predominant form in the overall granular population. In general, the granule is shown with an external electron-lucent halo and electron-dense core. The ultrastructure pattern in the granules of the insulin-immunoreactive endocrine cells was similar to that of the B cells of pancreatic islets in rats.

  8. Sarcocystis neurona infections in sea otter (Enhydra lutris): evidence for natural infections with sarcocysts and transmission of infection to opossums (Didelphis virginiana)

    USGS Publications Warehouse

    Dubey, J.P.; Rosypal, A.C.; Rosenthal, B.M.; Thomas, N.J.; Lindsay, D.S.; Stanek, J.F.; Reed, S.M.; Saville, W.J.A.

    2001-01-01

    Although Sarcocystis neurona has been identified in an array of terrestrial vertebrates, recent recognition of its capacity to infect marine mammals was unexpected. Here, sarcocysts from 2 naturally infected sea otters (Enhydra lutris) were characterized biologically, ultrastructurally, and genetically. DNA was extracted from frozen muscle of the first of these sea otters and was characterized as S. neurona by polymerase chain reation (PCR) amplification followed by restriction fragment length polymorphism analysis and sequencing. Sarcocysts from sea otter no. 1 were up to 350 I?m long, and the villar protrusions on the sarcocyst wall were up to 1.3 I?m long and up to 0.25 I?m wide. The villar protrusions were tapered towards the villar tip. Ultrastructurally, sarcocysts were similar to S. neurona sarcocysts from the muscles of cats experimentally infected with S. neurona sporocysts. Skeletal muscles from a second sea otter failed to support PCR amplification of markers considered diagnostic for S. neurona but did induce the shedding of sporocysts when fed to a laboratory-raised opossum (Didelphis virginiana). Such sporocysts were subsequently fed to knockout mice for the interferon-gamma gene, resulting in infections with an agent identified as S. neurona on the basis of immunohistochemistry, serum antibodies, and diagnostic sequence detection. Thus, sea otters exposed to S. neurona may support the development of mature sarcocysts that are infectious to competent definitive hosts.

  9. Cognitive Mapping by the Blind.

    ERIC Educational Resources Information Center

    Casey, Steven M.

    1978-01-01

    In an effort to study the cognitive mapping abilities of blind persons, tactile maps of a school campus were made by ten congenitally blind and ten blindfolded partially sighted high school students. (Author)

  10. Sighted Children Learn About Blindness

    ERIC Educational Resources Information Center

    Scheffers, Wenda L.

    1977-01-01

    In a 20-lesson unit, sighted second-to fourth-grade students were taught about the long cane, guide dogs, daily living skills, eye physiology, causes of blindness, eye care, braille, and attitudes toward blindness. (CL)

  11. Overview on Deaf-Blindness

    MedlinePlus

    ... children and youth who are deaf-blind. Monmouth: Teaching Research Division. Wolff Heller, K. & Kennedy, C. (1994). Etiologies and characteristics of deaf-blindness. Monmouth: Teaching Research Publications. Watson, D., & Taff-Watson, M. (Eds.), ( ...

  12. Testing Children for Color Blindness

    MedlinePlus

    ... blindness as soon as age 4, finds Caucasian boys most likely to be color blind among different ... age 4. In addition, researchers found that Caucasian boys have the highest prevalence among four major ethnicities, ...

  13. Blinded by Science.

    ERIC Educational Resources Information Center

    Snyder, Tom

    1994-01-01

    Huge infusion of technology is coming into education; nothing can stop it, because so much money is involved. With computer marketers in driver seat instead of teachers, schools risk being blinded by science. Vendors have coopted progressive education buzzwords, including "frontal teaching,""linear thinking," and "computer…

  14. [Blindness and visual rehabilitation].

    PubMed

    Matonti, F; Roux, S; Denis, D; Picaud, S; Chavane, F

    2015-02-01

    Blindness and visual impairment are a major public health problem all over the world and in all societies. A large amount of basic science and clinical research aims to rehabilitate patients and help them become more independent. Various methods are explored from cell and molecular therapy to prosthetic interfaces. We review the various treatment alternatives, describing their results and their limitations.

  15. Blindness in the Toybox

    ERIC Educational Resources Information Center

    Swartz, Edward M.

    1973-01-01

    The author proposes that toys which have been shown to cause blindness (such as dart guns, bows and arrows, peashooters, air guns, and slingshots) be banned, and suggests that government regulatory agencies and the toy industry have been lax in acting on their expressed concern for safety. (DB)

  16. The blind beautiful eye.

    PubMed

    Feinsod, M

    2000-03-01

    Master Jehan Yperman, a medieval surgeon, observed that when the optic nerve is injured, the eye becomes blind and beautiful. This is an attempt to trace the footsteps of this forgotten surgeon and to track the history of the cosmetic use of the belladonna herb, as well as the concept of amaurotic mydriasis.

  17. Homer: The Blind Bard

    ERIC Educational Resources Information Center

    Doorley, Rachelle; King, Judith

    2005-01-01

    This article describes notable cultural, historical, and artistic elements emanating from sculptures originating in ancient Greece. The "blind bard" and its connection to the legendary Greek poet, Homer; Homer's impact on literary history; trends among Roman sculptures; and Roman replication of Greek art are described. Questions to…

  18. Corneal blindness and xenotransplantation.

    PubMed

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

    2014-01-01

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

  19. Programs for the Deaf Blind.

    ERIC Educational Resources Information Center

    American Annals of the Deaf, 1987

    1987-01-01

    The directory lists 30 programs for deaf-blind children and youth, the 10 regional offices of the Helen Keller National Center for Deaf-Blind Youths and Adults, and five programs for training teachers of the deaf-blind. Provided for each program is address, director's name, and phone number. (DB)

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

    PubMed

    Permin, H; Norn, M

    2001-01-01

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

  1. Prevalence of and risk factors associated with the presence of Sarcocystis neurona sporocysts in opossum (Didelphis virginiana) from Michigan: a retrospective study.

    PubMed

    Elsheikha, Hany M; Murphy, Alice J; Mansfield, Linda S

    2004-11-10

    From April 1996 to December 2002 the prevalence of Sarcocystis neurona sporocysts in North American opossum (Didelphis virginiana) in Southern Michigan was estimated. Sporocysts of S. neurona were found in intestinal scrapings from 31 (15%) of 206 examined opossum. The frequency of infection was higher in adult animals (26/206; 12.6%) and females (19/206; 9.2%) than in juveniles (5/206; 2.4%) and males (12/206; 5.8%). Also, prevalence of S. neurona sporocysts in opossums in relation to factors such as age, sex, season, body condition, presence of concomitant infection, and presence of young in the pouch of females was studied in detail over the course of the year, 2002. Univariate analyses identified the following factors as being associated with the presence of S. neurona sporocysts in opossums: (i) for age, adult (odd ratio [OR] = 2.074, P = 0.0005); (ii) for sex, female (OR = 7.016, P = 0.0119); (iii) for season, summer (OR = 7.917, P = 0.0032) and spring (OR = 4.071, P = 0.1063); (iv) for body condition, poor (OR = 3.50, P = 0.1200) and good (OR = 1.167, P = 0.8637); (v) for the presence of concomitant infection (OR = 23.056, P = 0001), and (vi) for the presence of young in the pouch of females (OR = 40.083, P = 0.0001). Multivariate logistic-regression analyses selected the following factors as being significantly associated with presence of S. neurona sporocysts in opossums: (i) for the presence of concomitant infection (OR = 8.722, P = 0.0160) and (ii) for the presence of young in the pouch of females (OR = 31.915, P = 0.0065). The prevalence of S. neurona sporocysts in D. virginiana suggests that this opossum may constitute an ample reservoir of infection to other animals in the northern United States.

  2. Which Factors Determine Spatial Segregation in the South American Opossums (Didelphis aurita and D. albiventris)? An Ecological Niche Modelling and Geometric Morphometrics Approach

    PubMed Central

    Cáceres, Nilton Carlos; de Moraes Weber, Marcelo; Melo, Geruza Leal; Meloro, Carlo; Sponchiado, Jonas; Carvalho, Renan dos Santos; Bubadué, Jamile de Moura

    2016-01-01

    Didelphis albiventris and D. aurita are Neotropical marsupials that share a unique evolutionary history and both are largely distributed throughout South America, being primarily allopatric throughout their ranges. In the Araucaria moist forest of Southern Brazil these species are sympatric and they might potentially compete having similar ecology. For this reason, they are ideal biological models to address questions about ecological character displacement and how closely related species might share their geographic space. Little is known about how two morphologically similar species of marsupials may affect each other through competition, if by competitive exclusion and competitive release. We combined ecological niche modeling and geometric morphometrics to explore the possible effects of competition on their distributional ranges and skull morphology. Ecological niche modeling was used to predict their potential distribution and this method enabled us to identify a case of biotic exclusion where the habit generalist D. albiventris is excluded by the presence of the specialist D. aurita. The morphometric analyses show that a degree of shape discrimination occurs between the species, strengthened by allometric differences, which possibly allowed them to occupy marginally different feeding niches supplemented by behavioral shift in contact areas. Overlap in skull morphology is shown between sympatric and allopatric specimens and a significant, but weak, shift in shape occurs only in D. aurita in sympatric areas. This could be a residual evidence of a higher past competition between both species, when contact zones were possibly larger than today. Therefore, the specialist D. aurita acts a biotic barrier to D. albiventris when niche diversity is not available for coexistence. On the other hand, when there is niche diversification (e.g. habitat mosaic), both species are capable to coexist with a minimal competitive effect on the morphology of D. aurita. PMID

  3. Experimental infection of opossums Didelphis aurita by Rickettsia rickettsii and evaluation of the transmission of the infection to ticks Amblyomma cajennense.

    PubMed

    Horta, Maurício C; Moraes-Filho, Jonas; Casagrande, Renata A; Saito, Tais B; Rosa, Simone C; Ogrzewalska, Maria; Matushima, Eliana R; Labruna, Marcelo B

    2009-02-01

    The present study evaluated the infection of opossums (Didelphis aurita) by Rickettsia rickettsii and their role as amplifier hosts for horizontal transmission of R. rickettsii to Amblyomma cajennense ticks. Three groups of opossums were evaluated: on day 0, group 1 (G1) was inoculated intraperitoneally with R. rickettsii; group 2 (G2) was infested by R. rickettsii-infected ticks; and group 3 (G3) was the uninfected control group. Opossum rectal temperature was measured daily. Blood samples were collected every 2 to 4 days during 30 days, and used to (1) inoculate guinea pigs intraperitoneally; (2) extract DNA followed by real-time polymerase chain reaction (PCR) targeting the rickettsial gene gltA; (3) study hematology; (4) detect R. rickettsii-reactive antibodies by indirect immunofluorescence assay (IFA). Blood was also collected every 10 days from days 30 to 180, to be tested by serology. Opossums were infested by uninfected A. cajennense larvae and nymphs from days 3 to 15. Engorged ticks were collected and allowed to molt in an incubator. Thereafter, the subsequent flat ticks were allowed to feed on uninfected rabbits, which were tested for seroconversion by IFA. Samples of flat ticks were also tested by real-time PCR. All G1 and G2 opossums became infected by R. rickettsii, as demonstrated by realtime PCR or/and guinea pig inoculation, but they showed no clinical abnormality. Rickettsemia was first detected at days 2 to 8, lasting intermittently till days 1 to 30. Approximately 18% and 5% of the flat ticks previously fed on G1 and G2 opossums, respectively, became infected by R. rickettsii, but only the rabbits infested with G1-derived ticks seroconverted. The study demonstrated that R. rickettsii was capable of infecting opossums without causing illness and developing rickettsemia capable of causing infection in guinea pigs and ticks, although the infection rate in ticks was low.

  4. Gene therapy for blindness.

    PubMed

    Sahel, José-Alain; Roska, Botond

    2013-07-08

    Sight-restoring therapy for the visually impaired and blind is a major unmet medical need. Ocular gene therapy is a rational choice for restoring vision or preventing the loss of vision because most blinding diseases originate in cellular components of the eye, a compartment that is optimally suited for the delivery of genes, and many of these diseases have a genetic origin or genetic component. In recent years we have witnessed major advances in the field of ocular gene therapy, and proof-of-concept studies are under way to evaluate the safety and efficacy of human gene therapies. Here we discuss the concepts and recent advances in gene therapy in the retina. Our review discusses traditional approaches such as gene replacement and neuroprotection and also new avenues such as optogenetic therapies. We conjecture that advances in gene therapy in the retina will pave the way for gene therapies in other parts of the brain.

  5. Postpartum cortical blindness.

    PubMed

    Faiz, Shakeel Ahmed

    2008-09-01

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

  6. Blind shaft development

    SciTech Connect

    Fiscor, S.

    2009-02-15

    The article discusses how Shaft Drillers International (SDI) is breaking new ground in shaft development and ground stabilization. Techniques of blind shaft drilling and raise bore shaft development developed by SDI are briefly explained. An associated company, Coastal Drilling East, deals with all types of ground improvement such as pre-grouting work for shafts, grouting of poor soil and water leaks into the mine. 3 photos.

  7. Geometry of blind thrusts

    SciTech Connect

    Kligfield, R.; Geiser, P.; Geiser, J.

    1985-01-01

    Blind thrusts are structures which at no time in their history broke the erosion surface and along which displacement progressively changes upwards. Faults of the stiff layer along which displacement progressively decreases to zero (tip) are one prominent type of blind thrust structure. Shortening above such tips is accommodated entirely by folding whereas shortening below the tip is partitioned between folding and faulting. For these types of faults it is possible to determine the original length of the stiff layer for balancing purposes. A systematic methodology for line length and area restoration is outlined for determining blind thrust geometry. Application of the methodology is particularly suitable for use with microcomputers. If the folded form of the cover is known along with the position of the fault and its tip, then it is possible to locate hanging and footwall cutoffs. If the fault trajectory, tip, and a single hanging wall footwall cutoff pair are known, then the folded form of the cover layer can be determined. In these constructions it is necessary to specify pin lines for balancing purposes. These pin lines may or may not have a zero displacement gradient, depending upon the amount of simple shear deformation. Examples are given from both Laramide structures of the western USA and the Appalachians.

  8. Unsupervised Blind Deconvolution

    NASA Astrophysics Data System (ADS)

    Baena-Galle, R.; Kann, L.; Mugnier, L.; Gudimetla, R.; Johnson, R.; Gladysz, S.

    2013-09-01

    "Blind" deconvolution is rarely executed blindly. All available methods have parameters which the user fine-tunes until the most visually-appealing reconstruction is achieved. The "art" of deconvolution is to find constraints which allow for the best estimate of an object to be recovered, but in practice these parameterized constraints often reduce deconvolution to the struggle of trial and error. In the course of AFOSR-sponsored activities we are developing a general maximum a posteriori framework for the problem of imaging through atmospheric turbulence, with the emphasis on multi-frame blind deconvolution. Our aim is to develop deconvolution strategy which is reference-less, i.e. no calibration PSF is required, extendable to longer exposures, and applicable to imaging with adaptive optics. In the first part of the project the focus has been on developing a new theory of statistics of images taken through turbulence, both with-, and without adaptive optics. Images and their Fourier transforms have been described as random phasor sums, their fluctuations controlled by wavefront "cells" and moments of the phase. The models were validated using simulations and real data from the 3.5m telescope at the Starfire Optical Range in New Mexico. Another important ingredient of the new framework is the capability to estimate the average PSF automatically from the target observations. A general approach, applicable to any type of object, has been proposed. Here use is made of an object-cancelling transformation of the image sequence. This transformation yields information about the atmospheric PSF. Currently, the PSF estimation module and the theoretical constraints on PSF variability are being incorporated into multi-frame blind deconvolution. In preliminary simulation tests we obtained significantly sharper images with respect to the starting observations and PSF estimates which closely track the input kernels. Thanks to access to the SOR 3.5m telescope we are now testing

  9. Fighting blindness with microelectronics.

    PubMed

    Zrenner, Eberhart

    2013-11-06

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

  10. Multiscale image blind denoising.

    PubMed

    Lebrun, Marc; Colom, Miguel; Morel, Jean-Michel

    2015-10-01

    Arguably several thousands papers are dedicated to image denoising. Most papers assume a fixed noise model, mainly white Gaussian or Poissonian. This assumption is only valid for raw images. Yet, in most images handled by the public and even by scientists, the noise model is imperfectly known or unknown. End users only dispose the result of a complex image processing chain effectuated by uncontrolled hardware and software (and sometimes by chemical means). For such images, recent progress in noise estimation permits to estimate from a single image a noise model, which is simultaneously signal and frequency dependent. We propose here a multiscale denoising algorithm adapted to this broad noise model. This leads to a blind denoising algorithm which we demonstrate on real JPEG images and on scans of old photographs for which the formation model is unknown. The consistency of this algorithm is also verified on simulated distorted images. This algorithm is finally compared with the unique state of the art previous blind denoising method.

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

    PubMed

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

    2016-02-01

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

  12. In vivo strains in the femur of the Virginia opossum (Didelphis virginiana) during terrestrial locomotion: testing hypotheses of evolutionary shifts in mammalian bone loading and design.

    PubMed

    Butcher, Michael T; White, Bartholomew J; Hudzik, Nathan B; Gosnell, W Casey; Parrish, John H A; Blob, Richard W

    2011-08-01

    Terrestrial locomotion can impose substantial loads on vertebrate limbs. Previous studies have shown that limb bones from cursorial species of eutherian mammals experience high bending loads with minimal torsion, whereas the limb bones of non-avian reptiles (and amphibians) exhibit considerable torsion in addition to bending. It has been hypothesized that these differences in loading regime are related to the difference in limb posture between upright mammals and sprawling reptiles, and that the loading patterns observed in non-avian reptiles may be ancestral for tetrapod vertebrates. To evaluate whether non-cursorial mammals show loading patterns more similar to those of sprawling lineages, we measured in vivo strains in the femur during terrestrial locomotion of the Virginia opossum (Didelphis virginiana), a marsupial that uses more crouched limb posture than most mammals from which bone strains have been recorded, and which belongs to a clade phylogenetically between reptiles and the eutherian mammals studied previously. The presence of substantial torsion in the femur of opossums, similar to non-avian reptiles, would suggest that this loading regime likely reflects an ancestral condition for tetrapod limb bone design. Strain recordings indicate the presence of both bending and appreciable torsion (shear strain: 419.1 ± 212.8 με) in the opossum femur, with planar strain analyses showing neutral axis orientations that placed the lateral aspect of the femur in tension at the time of peak strains. Such mediolateral bending was unexpected for a mammal running with near-parasagittal limb kinematics. Shear strains were similar in magnitude to peak compressive axial strains, with opossum femora experiencing similar bending loads but higher levels of torsion compared with most previously studied mammals. Analyses of peak femoral strains led to estimated safety factor ranges of 5.1-7.2 in bending and 5.5-7.3 in torsion, somewhat higher than typical mammalian values

  13. Corneal blindness: a global perspective.

    PubMed Central

    Whitcher, J. P.; Srinivasan, M.; Upadhyay, M. P.

    2001-01-01

    Diseases affecting the cornea are a major cause of blindness worldwide, second only to cataract in overall importance. The epidemiology of corneal blindness is complicated and encompasses a wide variety of infectious and inflammatory eye diseses that cause corneal scarring, which ultimately leads to functional blindness. In addition, the prevalence of corneal disease varies from country to country and even from one population to another. While cataract is responsible for nearly 20 million of the 45 million blind people in the world, the next major cause is trachoma which blinds 4.9 million individuals, mainly as a result of corneal scarring and vascularization. Ocular trauma and corneal ulceration are significant causes of corneal blindness that are often underreported but may be responsible for 1.5-2.0 million new cases of monocular blindness every year. Causes of childhood blindness (about 1.5 million worldwide with 5 million visually disabled) include xerophthalmia (350,000 cases annually), ophthalmia neonatorum, and less frequently seen ocular diseases such as herpes simplex virus infections and vernal keratoconjunctivitis. Even though the control of onchocerciasis and leprosy are public health success stories, these diseases are still significant causes of blindness--affecting a quarter of a million individuals each. Traditional eye medicines have also been implicated as a major risk factor in the current epidemic of corneal ulceration in developing countries. Because of the difficulty of treating corneal blindness once it has occurred, public health prevention programmes are the most cost-effective means of decreasing the global burden of corneal blindness. PMID:11285665

  14. Overview on Deaf-Blindness

    ERIC Educational Resources Information Center

    Miles, Barbara

    2008-01-01

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

  15. Biological Models for Blind Students.

    ERIC Educational Resources Information Center

    Franks, Frank L.; Murr, Marvin J.

    1978-01-01

    In response to an expressed need for inexpensive biological models for blind students, the American Printing House for the Blind has developed a set of 19 plastic models (schematics), which illustrate representative species of the major invertebrate phyla and component structures of flowering plants. (Author)

  16. How to Succeed at Being Blind

    ERIC Educational Resources Information Center

    Selvin, Hanan C.

    1976-01-01

    The author, a professional sociologist who lost his sight, provides practical advice and information to people who are becoming blind or who have recently become blind, and others who know or work with blind persons. (Author/IM)

  17. Blind Pilot Decontamination

    NASA Astrophysics Data System (ADS)

    Muller, Ralf R.; Cottatellucci, Laura; Vehkapera, Mikko

    2014-10-01

    A subspace projection to improve channel estimation in massive multi-antenna systems is proposed and analyzed. Together with power-controlled hand-off, it can mitigate the pilot contamination problem without the need for coordination among cells. The proposed method is blind in the sense that it does not require pilot data to find the appropriate subspace. It is based on the theory of large random matrices that predicts that the eigenvalue spectra of large sample covariance matrices can asymptotically decompose into disjoint bulks as the matrix size grows large. Random matrix and free probability theory are utilized to predict under which system parameters such a bulk decomposition takes place. Simulation results are provided to confirm that the proposed method outperforms conventional linear channel estimation if bulk separation occurs.

  18. Load Induced Blindness

    PubMed Central

    Macdonald, James S. P.; Lavie, Nilli

    2008-01-01

    Although the perceptual load theory of attention has stimulated a great deal of research, evidence for the role of perceptual load in determining perception has typically relied on indirect measures that infer perception from distractor effects on reaction times or neural activity (see N. Lavie, 2005d`) was consistently reduced with high, compared to low, perceptual load but was unaffected by the level of working memory load. Because alternative accounts in terms of expectation, memory, response bias, and goal-neglect due to the more strenuous high load task were ruled out, these experiments clearly demonstrate that high perceptual load determines conscious perception, impairing the ability to merely detect the presence of a stimulus—a phenomenon of load induced blindness. PMID:18823196

  19. Drug user treatment failure blindness?

    PubMed

    Einstein, Stan

    2012-01-01

    An ethnographic case study of a "failed" single goal (abstinence) based individual and group therapy treatment of a New York City, Harlem-based, single, young-adult of color, IDU, mother, which ended in "death by overdose," after a period of abstinence, is presented almost 50 years later, in which complex, multidimensional structural barriers, "normed," consensualized, ideologically-driven preconceptions and an array of contextual, situational and relevant stakeholder factors, which may have resulted in intervention "failure blindness," are reviewed. The need to introduce failure analysis, blindness and management, as well as success analysis, blindness and management, as integral parts of treatment planning, implementation and assessment is raised.

  20. Perceptual Repetition Blindness Effects

    NASA Technical Reports Server (NTRS)

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

    1994-01-01

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

  1. Reusable captive blind fastener

    NASA Technical Reports Server (NTRS)

    Peterson, S. A. (Inventor)

    1981-01-01

    A one piece reusable fastener capable of joining materials together from one side (blind backside) comprises a screw driven pin ending in a wedge-shaped expander cone. The cone cooperates within a slotted collar end which has a number of tangs on a cylindrical body. The fastener is set by inserting it through aligned holes in the workpieces to be joined. Turning the pin in one direction draws the cone into the collar, deforming the tangs radially outward to mate with tapered back-tapered hold in the workpiece, thus fastening the two pieces together. Reversing the direction of the pin withdraws the cone from the collar, and allows the tangs to resume their contracted configuration without withdrawing the fastener from the insertion hole. The fastener is capable of joining materials together from only one side with substantial strength in tension and shear over many resue attachment cycles, with no special operations on the main assembly parts other than the tapering of the back end of the insertion hole.

  2. Orthographic repetition blindness.

    PubMed

    Harris, C L; Morris, A L

    2000-11-01

    Repetition blindness (RB) is the failure to report the second occurrence of a repeated word, when words are sequentially and briefly displayed (Kanwisher, 1987). RB is also observed for non-identical words, such as home, dome. Explanations for non-identity RB assume that similarity at the level of the whole word causes the second word to be suppressed ("similarity inhibition"). Three experiments demonstrate that RB is robust for diverse types of orthographic relatedness, including critical words that share only their first initial letter, their last two letters, first three letters, middle three letters, beginning and final letters, three alternating letters, and three non-aligned letters (as in chance hand). The theoretical construct of similarity inhibition may be able to account for these data, although one mechanism previously proposed in the literature, neighbourhood inhibition, is probably not a useful way to explain the data on RB for words sharing only one or two letters. We introduce an alternative explanation for orthographic RB: Only the repeated letters are suppressed, and amount of RB depends on how easily the perceiver can reconstruct the target word from the non-suppressed letters.

  3. Perceptual repetition blindness effects.

    PubMed

    Hochhaus, L; Johnston, J C

    1996-04-01

    Repetition blindness (RB) may reveal a new limitation on human perceptual processing. Recently, however, researchers have attributed RB to postperceptual processes. The standard rapid serial visual presentation (RSVP) paradigm used in most RB studies is open to such objections. The "single-frame" paradigm introduced by J. C. Johnston and B. L. Hale (1984) allowed investigation of RB with minimal memory demands. Participants made a judgment about whether 1 masked target word was the same or different than a posttarget probe. Confidence ratings permitted use of signal detection methods. In the critical condition for RB, a precue of the posttarget word was provided prior to the target stimulus so that the required judgment amounted to whether the target did or did not repeat the precue word. In control treatments, the precue was an unrelated word or a dummy. Results showed that perceptual sensitivity was significantly reduced in the RB condition relative to baseline control conditions. The data showed that RB can be obtained under conditions in which memory problems are minimal and perceptual sensitivity is assessed independently of biases. RB therefore can be a perceptual phenomenon.

  4. Load induced blindness.

    PubMed

    Macdonald, James S P; Lavie, Nilli

    2008-10-01

    Although the perceptual load theory of attention has stimulated a great deal of research, evidence for the role of perceptual load in determining perception has typically relied on indirect measures that infer perception from distractor effects on reaction times or neural activity (see N. Lavie, 2005, for a review). Here we varied the level of perceptual load in a letter-search task and assessed its effect on the conscious perception of a search-irrelevant shape stimulus appearing in the periphery, using a direct measure of awareness (present/absent reports). Detection sensitivity (d') was consistently reduced with high, compared to low, perceptual load but was unaffected by the level of working memory load. Because alternative accounts in terms of expectation, memory, response bias, and goal-neglect due to the more strenuous high load task were ruled out, these experiments clearly demonstrate that high perceptual load determines conscious perception, impairing the ability to merely detect the presence of a stimulus--a phenomenon of load induced blindness.

  5. Vision following extended congenital blindness.

    PubMed

    Ostrovsky, Yuri; Andalman, Aaron; Sinha, Pawan

    2006-12-01

    Animal studies suggest that early visual deprivation can cause permanent functional blindness. However, few human data on this issue exist. Given enough time for recovery, can a person gain visual skills after several years of congenital blindness? In India, we recently had an unusual opportunity to work with an individual whose case history sheds light on this question. S.R.D. was born blind, and remained so until age 12. She then underwent surgery for the removal of dense congenital cataracts. We evaluated her performance on an extensive battery of visual tasks 20 years after surgery. We found that although S.R.D.'s acuity is compromised, she is proficient on mid- and high-level visual tasks. These results suggest that the human brain retains an impressive capacity for visual learning well into late childhood. They have implications for current conceptions of cortical plasticity and provide an argument for treating congenital blindness even in older children.

  6. Laboratory Techniques for the Blind

    ERIC Educational Resources Information Center

    Tombaugh, Dorothy

    1972-01-01

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

  7. Student Art for Blind Children.

    ERIC Educational Resources Information Center

    Vanda, Kay

    1982-01-01

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

  8. American Foundation for the Blind

    MedlinePlus

    ... and Electronic Materials Webinars and Online Courses Accessible Technology AccessWorld ® : Technology News for People Who Are Blind or Visually Impaired Find Assistive Technology Products Using Technology: Apps, Guides, Video Demonstrations, and ...

  9. What It's Like to Be Color Blind

    MedlinePlus

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

  10. Programs for the Deaf-Blind.

    ERIC Educational Resources Information Center

    American Annals of the Deaf, 1991

    1991-01-01

    This directory lists contact information for programs for the deaf-blind in the United States in 3 categories: (1) programs for deaf-blind children and youth (29 programs listed); (2) Helen Keller National Center for Deaf-Blind Youth and Adults (1 national and 10 regional offices); and (3) programs for training teachers of the deaf-blind (4…

  11. A Perceptual Repetition Blindness Effect

    NASA Technical Reports Server (NTRS)

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

    1994-01-01

    Before concluding Repetition Blindness is a perceptual phenomenon, alternative explanations based on memory retrieval problems and report bias must be rejected. Memory problems were minimized by requiring a judgment about only a single briefly displayed field. Bias and sensitivity effects were empirically measured with an ROC-curve analysis method based on confidence ratings. Results from five experiments support the hypothesis that Repetition Blindness can be a perceptual phenomenon.

  12. ESTIMATED STATISTICS ON BLINDNESS AND VISION PROBLEMS. NATIONAL SOCIETY FOR THE PREVENTION OF BLINDNESS FACT BOOK.

    ERIC Educational Resources Information Center

    HATFIELD, ELIZABETH M.

    CURRENT ESTIMATES AND SOME TREND DATA ARE PRESENTED ON THE FOLLOWING SUBJECTS -- POPULATION GROWTH (1940-1960), PREVALENCE OF LEGAL BLINDNESS, NEW CASES OF LEGAL BLINDNESS, AGE DISTRIBUTION OF LEGALLY BLIND PERSONS, CAUSES OF LEGAL BLINDNESS, CHANGING PATTERNS IN CAUSES OF LEGAL BLINDNESS, CASES OF GLAUCOMA, SCHOOL CHILDREN NEEDING EYE CARE,…

  13. 20 CFR 416.982 - Blindness under a State plan.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 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...

  14. 20 CFR 416.983 - How we evaluate statutory blindness.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 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...

  15. 20 CFR 416.983 - How we evaluate statutory blindness.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 2 2014-04-01 2014-04-01 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...

  16. 20 CFR 416.982 - Blindness under a State plan.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 2 2012-04-01 2012-04-01 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...

  17. 20 CFR 416.983 - How we evaluate statutory blindness.

    Code of Federal Regulations, 2010 CFR

    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...

  18. 20 CFR 416.982 - Blindness under a State plan.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 2 2013-04-01 2013-04-01 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...

  19. 20 CFR 416.982 - Blindness under a State plan.

    Code of Federal Regulations, 2010 CFR

    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...

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

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 2 2013-04-01 2013-04-01 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...

  1. 20 CFR 416.983 - How we evaluate statutory blindness.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 2 2012-04-01 2012-04-01 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...

  2. 20 CFR 416.982 - Blindness under a State plan.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 2 2014-04-01 2014-04-01 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...

  3. [Aiming for zero blindness].

    PubMed

    Nakazawa, Toru

    2015-03-01

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

  4. Do the blinds smell better?

    PubMed

    Luers, Jan Christoffer; Mikolajczak, Stefanie; Hahn, Moritz; Wittekindt, Claus; Beutner, Dirk; Hüttenbrink, Karl-Bernd; Damm, Michael

    2014-07-01

    If people lose a sense organ, there is thought to be an increase in the remaining sensory functions. Previous studies showed ambiguous results on this topic. In a prospective matched pair case-control study on 46 blind and 46 normal-sighted subjects, the olfactory performance was examined using the Sniffin' Sticks Test [threshold-discrimination-identification (TDI) test], determining the olfactory threshold, the identification and the discrimination performance. There was no significant difference between the groups. Neither the overall olfactory performance (TDI score) nor any of its subtests did correlate with the vision or with the duration of blindness. The study could not detect any superior smell abilities of blind subjects as compared to sighted subjects.

  5. Computer Reader for the Blind

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Optacon II uses the same basic technique of converting printed information into a tactile image as did Optacon. Optacon II can also be connected directly to a personal computer, which opens up a new range of job opportunities for the blind. Optacon II is not limited to reading printed words, it can convert any graphic image viewed by the camera. Optacon II demands extensive training for blind operators. TSI provides 60-hour training courses at its Mountain View headquarters and at training centers around the world. TeleSensory discontinued production of the Optacon as of December 1996.

  6. Night Blindness and Ancient Remedy

    PubMed Central

    Al Binali, H.A. Hajar

    2014-01-01

    The aim of this article is to briefly review the history of night blindness and its treatment from ancient times until the present. The old Egyptians, the Babylonians, the Greeks and the Arabs used animal liver for treatment and successfully cured the disease. The author had the opportunity to observe the application of the old remedy to a patient. Now we know what the ancients did not know, that night blindness is caused by Vitamin A deficiency and the animal liver is the store house for Vitamin A. PMID:25774260

  7. Indiana School for the Blind Visits Goddard

    NASA Video Gallery

    This video shows highlights of the Indiana School for the Blind and Visually Impaired, and the Indian Creek Public High School visit to NASA's Goddard Space Flight Center in June 2011. Both blind a...

  8. Reading Machines for Blind People.

    ERIC Educational Resources Information Center

    Fender, Derek H.

    1983-01-01

    Ten stages of developing reading machines for blind people are analyzed: handling of text material; optics; electro-optics; pattern recognition; character recognition; storage; speech synthesizers; browsing and place finding; computer indexing; and other sources of input. Cost considerations of the final product are emphasized. (CL)

  9. Aquatic Recreation for the Blind.

    ERIC Educational Resources Information Center

    Cordellos, Harry C.

    The sixth in a series of booklets on physical education and recreation for the handicapped describes aquatic activities for blind persons. Written by a partially sighted athlete, the document discusses swimming pool characteristics and special pools for the visually impaired. Qualities of swimming instructors are reviewed, and suggestions for…

  10. Piagetian Reasoning and the Blind.

    ERIC Educational Resources Information Center

    Hatwell, Yvette

    Available for the first time in an English translation, the book reports the results of a series of studies undertaken in the early 1960s on the cognitive development of children with congenital blindness. Chapters one and two review the literaure on such topics as the concept of sensory compensation and the nature of tactual space and provide…

  11. Repetition Blindness for Rotated Objects

    ERIC Educational Resources Information Center

    Hayward, William G.; Zhou, Guomei; Man, Wai-Fung; Harris, Irina M.

    2010-01-01

    Repetition blindness (RB) is the finding that observers often miss the repetition of an item within a rapid stream of words or objects. Recent studies have shown that RB for objects is largely unaffected by variations in viewpoint between the repeated items. In 5 experiments, we tested RB under different axes of rotation, with different types of…

  12. Repetition Blindness Occurs in Nonwords

    ERIC Educational Resources Information Center

    Harris, Catherine L.; Morris, Alison L.

    2004-01-01

    Theorists have predicted that repetition blindness (RB) should be absent for nonwords because they do not activate preexisting mental types. The authors hypothesized that RB would be observed for nonwords because RB can occur at a sublexical level. Four experiments showed that RB is observed for word-nonword pairs (noon noof), orthographically…

  13. The Blind Learning Aptitude Test.

    ERIC Educational Resources Information Center

    Newland, T. Ernest

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

  14. Metro Navigation for the Blind

    ERIC Educational Resources Information Center

    Sanchez, Jaime; Saenz, Mauricio

    2010-01-01

    This study evaluates the impact of using the software program AudioMetro, a tool that supports the orientation and mobility of people who are blind in the Metro system of Santiago de Chile. A quasi-experimental study considering experimental and control groups and using the paired Student's t in a two sample test analysis (pretest-posttest) was…

  15. Vision 2020: moving beyond blindness.

    PubMed

    Lewallen, Susan; Lansingh, Van; Thulasiraj, R D

    2014-09-01

    Most industrialized countries and many emerging economies have chosen to define 'blindness' at a visual acuity above that which WHO uses. This reflects the increasing visual demands of modern society for tasks such as driving or using cell phones. Meeting these demands will require more highly skilled health workers using more sophisticated equipment than has generally been considered sufficient for primary eye care.

  16. Partially Blind Signatures Based on Quantum Cryptography

    NASA Astrophysics Data System (ADS)

    Cai, Xiao-Qiu; Niu, Hui-Fang

    2012-12-01

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

  17. Poverty and blindness in Africa.

    PubMed

    Naidoo, Kovin

    2007-11-01

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

  18. Psychomotor Development for the Deaf-Blind.

    ERIC Educational Resources Information Center

    Sherrill, Claudine

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

  19. Deaf-Blind Perspectives, 1997-1998.

    ERIC Educational Resources Information Center

    Deaf-Blind Perspectives, 1998

    1998-01-01

    This one-year collection of three serial issues focuses on problem solving skills for children with deaf-blindness, the history and change in the education of children who are deaf-blind since the rubella epidemic of the 1960's, and early identification of infants who are deaf-blind. Specific articles include: (1) "Research to Practice Focus…

  20. 45 CFR 233.70 - Blindness.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 2 2012-10-01 2012-10-01 false Blindness. 233.70 Section 233.70 Public Welfare... FINANCIAL ASSISTANCE PROGRAMS § 233.70 Blindness. (a) State plan requirements. A State plan under title X or XVI of the Social Security Act must: (1) Contain a definition of blindness in terms of...

  1. What It's Like to Be Color Blind

    MedlinePlus

    ... 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 ...

  2. Introduction to Deaf-Blindness Workshop.

    ERIC Educational Resources Information Center

    Rhodes, Larry

    This document presents the agenda and materials distributed at a 1-day introductory workshop on deaf-blindness. Introductory material explains the workshop's purpose and rules. A short test contrasts facts and myths about deaf-blindness. A handout presents information on the dynamics of deaf-blindness, etiologies in the adult deaf-blind…

  3. Model Deaf/Blind Prevocational Training Project.

    ERIC Educational Resources Information Center

    Stoddard, Denis W.; And Others

    Presented is a report of a 4-month project designed to review literature on projects pertaining to deaf-blind prevocational training, to implement a model prevocational program for six severely handicapped deaf-blind students (10 years old), and to conduct two workshops in the area of prevocational training for deaf-blind students. Provided in…

  4. Programs for the Deaf-Blind.

    ERIC Educational Resources Information Center

    American Annals of the Deaf, 1990

    1990-01-01

    The directory lists 28 state or multistate programs for deaf blind children and youth, the national center and 10 regional offices of the Helen Keller National Center for Deaf-Blind Youths and Adults, and 4 programs for training teachers of the deaf-blind. Information usually provided includes, address, director's name, and phone number. (DB)

  5. Analysis of the morphology and distribution of argentaffin, argyrophil and insulin-immunoreactive endocrine cells in the small intestine of the adult opossum Didelphis aurita (Wied-Neuwied, 1826).

    PubMed

    Basile, D R S; Novaes, R D; Marques, D C S; Fialho, M C Q; Neves, C A; Fonseca, C C

    2012-10-01

    The aim of this study was to identify and quantify the argyrophil, argentaffin and insulin-immunoreactive cells (IIC) in the small intestine of the opossum Didelphis aurita. Seven adult male specimens of opossums were investigated. The animals were captured, and their blood insulin levels were determined. After euthanasia, fragments of the small intestine were processed for light microscopy and transmission electron microscopy, and submitted to histochemistry and immunohistochemistry for identification of argyrophil and argentaffin endocrine cells, and IIC. Argyrophil and argentaffin cells were identified in the intestinal villi and Liberkühn crypts, whereas IIC were present exclusively in the crypts. Ultrastructure of the IIC revealed cytoplasmic granules of different sizes and electron densities. The numbers of IIC per mm(2) in the duodenum and jejunum were higher than in the ileum (p<0.05). The animals had low levels of blood insulin (2.8 ± 0.78 μIU/ml). There was no correlation between insulin levels and the number of IIC in the small intestine. The IIC presented secretory granules, elongated and variable morphology. It is believed that insulin secretion by the IIC may influence the proliferation of cells in the Liberkühn crypts, and local glucose homeostasis, primarily in animals with low serum insulin levels, such as the opossum.

  6. Demonstration of blind quantum computing.

    PubMed

    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.

  7. Mobility aid for the blind

    NASA Technical Reports Server (NTRS)

    1982-01-01

    A project to develop an effective mobility aid for blind pedestrians which acquires consecutive images of the scenes before a moving pedestrian, which locates and identifies the pedestrian's path and potential obstacles in the path, which presents path and obstacle information to the pedestrian, and which operates in real-time is discussed. The mobility aid has three principal components: an image acquisition system, an image interpretation system, and an information presentation system. The image acquisition system consists of a miniature, solid-state TV camera which transforms the scene before the blind pedestrian into an image which can be received by the image interpretation system. The image interpretation system is implemented on a microprocessor which has been programmed to execute real-time feature extraction and scene analysis algorithms for locating and identifying the pedestrian's path and potential obstacles. Identity and location information is presented to the pedestrian by means of tactile coding and machine-generated speech.

  8. Change blindness and eyewitness testimony.

    PubMed

    Davies, Graham; Hine, Sarah

    2007-07-01

    The authors explored the relevance of research on change blindness to eyewitness identification and testimony under intentional and incidental memory conditions. Participants (N = 80, 40 men and 40 women) viewed a video enactment of a burglary in which the identity of the burglar changed at the halfway point of the film. Half of participants were briefed to remember the content, and the other half were not. All were tested for the recall of the content, awareness of the change, and ability to identify either or both of the burglars. Some 61% of participants did not notice the identity change. Rates of detection were significantly higher in participants in the intentional condition, who also recalled significantly more detail from the film. Awareness of change was also significantly related to content recall scores and accuracy of identification of both burglars. The results illustrate the interrelation between the eyewitness and change blindness literatures.

  9. Justifications shape ethical blind spots.

    PubMed

    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.

  10. Blind Identification of Graph Filters

    NASA Astrophysics Data System (ADS)

    Segarra, Santiago; Mateos, Gonzalo; Marques, Antonio G.; Ribeiro, Alejandro

    2017-03-01

    Network processes are often represented as signals defined on the vertices of a graph. To untangle the latent structure of such signals, one can view them as outputs of linear graph filters modeling underlying network dynamics. This paper deals with the problem of joint identification of a graph filter and its input signal, thus broadening the scope of classical blind deconvolution of temporal and spatial signals to the less-structured graph domain. Given a graph signal $\\mathbf{y}$ modeled as the output of a graph filter, the goal is to recover the vector of filter coefficients $\\mathbf{h}$, and the input signal $\\mathbf{x}$ which is assumed to be sparse. While $\\mathbf{y}$ is a bilinear function of $\\mathbf{x}$ and $\\mathbf{h}$, the filtered graph signal is also a linear combination of the entries of the lifted rank-one, row-sparse matrix $\\mathbf{x} \\mathbf{h}^T$. The blind graph-filter identification problem can thus be tackled via rank and sparsity minimization subject to linear constraints, an inverse problem amenable to convex relaxations offering provable recovery guarantees under simplifying assumptions. Numerical tests using both synthetic and real-world networks illustrate the merits of the proposed algorithms, as well as the benefits of leveraging multiple signals to aid the blind identification task.

  11. Blindness

    MedlinePlus

    ... Courier services use: Rockville, MD 20852) 301-451-2020 Research at NEI Office of the Scientific Director ... Eye Disease Education Program Glaucoma Education Program Low Vision Education Program Hispanic/Latino Program Vision and Aging ...

  12. A Rare Hydrocephalus Complication: Cortical Blindness.

    PubMed

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

    2015-01-01

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

  13. Blindness. [prosthetic devices and sensory aids

    NASA Technical Reports Server (NTRS)

    Pudenz, R. H.

    1974-01-01

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

  14. Do perceptions of blindness affect care?

    PubMed

    Orticio, L P

    1994-01-01

    1. Delivery of health care/services is influenced by society's perceptions of blindness. 2. Health care professionals may not be equipped to address inevitable blindness because they may not have been taught how. This lack of preparation during training is a need that must be addressed. 3. The challenge to change inaccurate societal perceptions should start with health professionals--especially those who work with fervor to fight blindness.

  15. Congenital color blindness in young Turkish men.

    PubMed

    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.

  16. Experimental infection of the opossum Didelphis aurita by Rickettsia felis, Rickettsia bellii, and Rickettsia parkeri and evaluation of the transmission of the infection to ticks Amblyomma cajennense and Amblyomma dubitatum.

    PubMed

    Horta, Maurício C; Sabatini, Guilherme S; Moraes-Filho, Jonas; Ogrzewalska, Maria; Canal, Raoní B; Pacheco, Richard C; Martins, Thiago F; Matushima, Eliana R; Labruna, Marcelo B

    2010-12-01

    This work evaluated the infection of opossums (Didelphis aurita) by Rickettsia felis, Rickettsia bellii, and Rickettsia parkeri and their role as amplifier hosts for horizontal transmission to Amblyomma cajennense and/or Amblyomma dubitatum ticks. Infection in D. aurita was induced by intraperitoneal inoculation with R. felis (n = 4 opossums), R. bellii (n = 4), and R. parkeri (n = 2). Another group of six opossums were inoculated intraperitoneally with Leibovitz-15 sterile culture medium, representing the uninfected groups (n = 2 opossums simultaneously to each infected group). Opossum blood samples collected during the study were used for DNA extraction, followed by real-time polymerase chain reaction targeting the rickettsial gene gltA, hematology, and detection of Rickettsia spp.-reactive antibodies by indirect immunofluorescence assay. Opossums were infested with uninfected A. cajennense and/or A. dubitatum for 30 days postinoculation (DPI). Flat ticks molted from ticks fed on opossums were allowed to feed on uninfected rabbits, which were tested for seroconversion by immunofluorescence assay. Samples of flat ticks were also tested by real-time polymerase chain reaction. Inoculated opossums showed no clinical abnormalities. Antibodies to Rickettsia spp. were first detected at the second to fourth DPI, with detectable titers until the 150th DPI. Rickettsemia was detected only in one opossum inoculated with R. parkeri, at the eighth DPI. Only one A. cajennense tick (2.0%) previously fed on a R. parkeri-inoculated opossum became infected. None of the rabbits infested with opossum-derived ticks seroconverted. The study demonstrated that R. felis, R. bellii, and R. parkeri were capable to produce antibody response in opossums, however, with undetectable rickettsemia for R. felis and R. bellii, and very low rickettsemia for R. parkeri. Further studies must be done with different strains of these rickettsiae, most importantly the strains that have

  17. Difference Blindness/Blindness Difference: Student Explorations of "Disability" over the Internet.

    ERIC Educational Resources Information Center

    Murphy, Kelly; And Others

    This case study describes the Internet correspondence using MOO, a multiuser, object-oriented site, that was developed between six third-grade girls and TCC, an adult with blindness. The changes from the students' original attitudes toward blindness, that blindness posed a barrier to communication and relationship-building, into their acceptance…

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

    PubMed

    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.

  19. Astronomy with the color blind

    NASA Astrophysics Data System (ADS)

    Smith, Donald A.; Melrose, Justyn

    2014-12-01

    The standard method to create dramatic color images in astrophotography is to record multiple black and white images, each with a different color filter in the optical path, and then tint each frame with a color appropriate to the corresponding filter. When combined, the resulting image conveys information about the sources of emission in the field, although one should be cautious in assuming that such an image shows what the subject would "really look like" if a person could see it without the aid of a telescope. The details of how the eye processes light have a significant impact on how such images should be understood, and the step from perception to interpretation is even more problematic when the viewer is color blind. We report here on an approach to manipulating stacked tricolor images that, while abandoning attempts to portray the color distribution "realistically," do result in enabling those suffering from deuteranomaly (the most common form of color blindness) to perceive color distinctions they would otherwise not be able to see.

  20. Glycoprotein Degradation in the Blind Loop Syndrome

    PubMed Central

    Prizont, Roberto

    1981-01-01

    Contents obtained from jejunum of normal controls, self-emptying and self-filling blind loop rats were analyzed for the presence of glycoprotein-degrading glycosidases. The blind loop syndrome was documented by the increased fat excretion and slower growth rate of self-filling blind loop rats 6 wk after surgery. With p-nitrophenylglycosides as substrate, the specific activity of α-N-acetylgalactosaminidase, a potential blood group A destroying glycosidase, was 0.90±0.40 mU/mg of protein. This level was 23-fold higher than the specific activity of normal controls. In partially purified self-filling blind loop contents, the activity of α-N-acetylgalactosaminidase was 9- to 70-fold higher than activities of self-emptying and normal controls. Antibiotic treatment with chloromycetin and polymyxin decreased 24-fold the glycosidase levels in self-filling blind loops. In experiments with natural substrate, the blood group A titer of a20,000g supernate from normal jejunal homogenates decreased 128-fold after 24-h incubation with blind loop contents. Normal contents failed to diminish the blood group reactivity of the natural substrate. Furthermore, blind loop contents markedly decreased the blood group A titer of isolated brush borders. Incubation between blind loop bacteria and mucosal homogenates or isolated brush borders labeled with d-[U-14C]glucosamine revealed increased production of labeled ether extractable organic acids. Likewise, intraperitoneal injection of d-[U-14C]glucosamine into self-filling blind loop rats resulted in incorporation of the label into luminal short chain fatty acids. These results suggest that glycosidases may provide a mechanism by which blind loop bacteria obtain sugars from intestinal glycoproteins. The released sugars are used and converted by bacteria into energy and organic acids. This use of the host's glycoproteins would allow blind loop bacteria to grow and survive within the lumen independent of exogenous sources. PMID:6257760

  1. New Identity-Based Blind Signature and Blind Decryption Scheme in the Standard Model

    NASA Astrophysics Data System (ADS)

    Phong, Le Trieu; Ogata, Wakaha

    We explicitly describe and analyse blind hierachical identity-based encryption (blind HIBE) schemes, which are natural generalizations of blind IBE schemes [20]. We then uses the blind HIBE schemes to construct: (1) An identity-based blind signature scheme secure in the standard model, under the computational Diffie-Hellman (CDH) assumption, and with much shorter signature size and lesser communication cost, compared to existing proposals. (2) A new mechanism supporting a user to buy digital information over the Internet without revealing what he/she has bought, while protecting the providers from cheating users.

  2. Deaf-Blind Perspectives, 2000-2001.

    ERIC Educational Resources Information Center

    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…

  3. Public-Facilities Locator For The Blind

    NASA Technical Reports Server (NTRS)

    Moore, Kevin D.

    1988-01-01

    Proposed optoelectronic system guides blind people to important locations in public buildings, With system, sightless person easily determines directions and distances of restrooms, water fountains, stairways, emergency exits, and elevators. Circuitry uncomplicated and inexpensive, in both transmitter and receiver. Readily-available light-emitting diodes, photodiodes, and integrated-circuit chips used to build locator aid for the blind.

  4. Individual Differences in Susceptibility to Inattentional Blindness

    ERIC Educational Resources Information Center

    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…

  5. Mentoring Transition-Age Youth with Blindness

    ERIC Educational Resources Information Center

    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…

  6. Vision Science: Can Rhodopsin Cure Blindness?

    PubMed

    Van Gelder, Russell N; Kaur, Kuldeep

    2015-08-17

    Outer retinal degeneration is the leading cause of blindness in the developed world. A new study now demonstrates that ectopic expression of human rhodopsin in the inner retina, mediated by viral gene therapy, can restore light sensitivity and some vision to mice blind from outer retinal degeneration.

  7. Blind Children's Concepts of How People See.

    ERIC Educational Resources Information Center

    Bigelow, A.

    1988-01-01

    The concepts of two totally blind children, ages four and five, concerning how people see, were evaluated by asking them to show objects to either sighted people or each other. Their performance indicated they understood that blind people need to feel objects but sighted persons do not. (Author/DB)

  8. Semantic and Phonemic Verbal Fluency in Blinds

    ERIC Educational Resources Information Center

    Nejati, Vahid; Asadi, Anoosh

    2010-01-01

    A person who has suffered the total loss of a sensory system has, indirectly, suffered a brain lesion. Semantic and phonologic verbal fluency are used for evaluation of executive function and language. The aim of this study is evaluation and comparison of phonemic and semantic verbal fluency in acquired blinds. We compare 137 blinds and 124…

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

    MedlinePlus

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

  10. Subcortical functional reorganization due to early blindness.

    PubMed

    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.

  11. Blind Braille readers mislocate tactile stimuli.

    PubMed

    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.

  12. Continuous-Variable Blind Quantum Computation

    NASA Astrophysics Data System (ADS)

    Morimae, Tomoyuki

    2012-12-01

    Blind quantum computation is a secure delegated quantum computing protocol where Alice, who does not have sufficient quantum technology at her disposal, delegates her 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. Protocols of blind quantum computation have been proposed for several qudit measurement-based computation models, such as the graph state model, the Affleck-Kennedy-Lieb-Tasaki model, and the Raussendorf-Harrington-Goyal topological model. Here, we consider blind quantum computation for the continuous-variable measurement-based model. We show that blind quantum computation is possible for the infinite squeezing case. We also show that the finite squeezing causes no additional problem in the blind setup apart from the one inherent to the continuous-variable measurement-based quantum computation.

  13. Efficient Universal Blind Quantum Computation

    NASA Astrophysics Data System (ADS)

    Giovannetti, Vittorio; Maccone, Lorenzo; Morimae, Tomoyuki; Rudolph, Terry G.

    2013-12-01

    We give a cheat sensitive protocol for blind universal quantum computation that is efficient in terms of computational and communication resources: it allows one party to perform an arbitrary computation on a second party’s quantum computer without revealing either which computation is performed, or its input and output. The first party’s computational capabilities can be extremely limited: she must only be able to create and measure single-qubit superposition states. The second party is not required to use measurement-based quantum computation. The protocol requires the (optimal) exchange of O(Jlog⁡2(N)) single-qubit states, where J is the computational depth and N is the number of qubits needed for the computation.

  14. Efficient universal blind quantum computation.

    PubMed

    Giovannetti, Vittorio; Maccone, Lorenzo; Morimae, Tomoyuki; Rudolph, Terry G

    2013-12-06

    We give a cheat sensitive protocol for blind universal quantum computation that is efficient in terms of computational and communication resources: it allows one party to perform an arbitrary computation on a second party's quantum computer without revealing either which computation is performed, or its input and output. The first party's computational capabilities can be extremely limited: she must only be able to create and measure single-qubit superposition states. The second party is not required to use measurement-based quantum computation. The protocol requires the (optimal) exchange of O(Jlog2(N)) single-qubit states, where J is the computational depth and N is the number of qubits needed for the computation.

  15. Auditory display for the blind

    NASA Technical Reports Server (NTRS)

    Fish, R. M. (Inventor)

    1974-01-01

    A system for providing an auditory display of two-dimensional patterns as an aid to the blind is described. It includes a scanning device for producing first and second voltages respectively indicative of the vertical and horizontal positions of the scan and a further voltage indicative of the intensity at each point of the scan and hence of the presence or absence of the pattern at that point. The voltage related to scan intensity controls transmission of the sounds to the subject so that the subject knows that a portion of the pattern is being encountered by the scan when a tone is heard, the subject determining the position of this portion of the pattern in space by the frequency and interaural difference information contained in the tone.

  16. Blindness in designing intelligent systems

    NASA Technical Reports Server (NTRS)

    Denning, Peter J.

    1988-01-01

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

  17. The PHENIX Hadron Blind Detector

    SciTech Connect

    Durham, J. M.

    2009-03-10

    Dielectron measurements by the PHENIX Experiment at RHIC are limited by the combinatorial background from electrons and positrons which are not produced in the same pair. The Hadron Blind Detector will allow a substantial reduction of this background by correctly identifying dielectrons from photon conversions and pion Dalitz decays which dominate the signal in the low mass region of the spectrum. Triple GEM stacks, with a CsI photocathode deposited on the uppermost GEM, detect Cherenkov light produced by electrons in a CF{sub 4} radiator. The transparency of CF{sub 4}, high quantum efficiency of CsI in the UV, and absence of a window between the gas radiator and the GEMs allow a large photoelectron yield, while minimizing the hadron signal. Results from the HBD in RHIC's Run-7 and preparations for upcoming runs are discussed.

  18. Blindness prevention programmes: past, present, and future.

    PubMed Central

    Resnikoff, S.; Pararajasegaram, R.

    2001-01-01

    Blindness and visual impairment have far-reaching implications for society, the more so when it is realized that 80% of visual disability is avoidable. The marked increase in the size of the elderly population, with their greater propensity for visually disabling conditions, presents a further challenge in this respect. However, if available knowledge and skills were made accessible to those communities in greatest need, much of this needless blindness could be alleviated. Since its inception over 50 years ago, and beginning with trachoma control, WHO has spearheaded efforts to assist Member States to meet the challenge of needless blindness. Since the establishment of the WHO Programme for the Prevention of Blindness in 1978, vast strides have been made through various forms of technical support to establish national prevention of blindness programmes. A more recent initiative, "The Global Initiative for the Elimination of Avoidable Blindness" (referred to as "VISION 2020--The Right to Sight"), launched in 1999, is a collaborative effort between WHO and a number of international nongovernmental organizations and other interested partners. This effort is poised to take the steps necessary to achieve the goal of eliminating avoidable blindness worldwide by the year 2020. PMID:11285666

  19. Auditory Spatial Recalibration in Congenital Blind Individuals

    PubMed Central

    Finocchietti, Sara; Cappagli, Giulia; Gori, Monica

    2017-01-01

    Blind individuals show impairments for auditory spatial skills that require complex spatial representation of the environment. We suggest that this is partially due to the egocentric frame of reference used by blind individuals. Here we investigate the possibility of reducing the mentioned auditory spatial impairments with an audio-motor training. Our hypothesis is that the association between a motor command and the corresponding movement's sensory feedback can provide an allocentric frame of reference and consequently help blind individuals in understanding complex spatial relationships. Subjects were required to localize the end point of a moving sound before and after either 2-min of audio-motor training or a complete rest. During the training, subjects were asked to move their hand, and consequently the sound source, to freely explore the space around the setup and the body. Both congenital blind (N = 20) and blindfolded healthy controls (N = 28) participated in the study. Results suggest that the audio-motor training was effective in improving space perception of blind individuals. The improvement was not observed in those subjects that did not perform the training. This study demonstrates that it is possible to recalibrate the auditory spatial representation in congenital blind individuals with a short audio-motor training and provides new insights for rehabilitation protocols in blind people. PMID:28261053

  20. Reversible cortical blindness: posterior reversible encephalopathy syndrome.

    PubMed

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

    2010-11-01

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

  1. Ancilla-driven universal blind quantum computation

    NASA Astrophysics Data System (ADS)

    Sueki, Takahiro; Koshiba, Takeshi; Morimae, Tomoyuki

    2013-06-01

    Blind quantum computation is a new quantum secure protocol, which enables Alice who does not have enough quantum technology to delegate her computation to Bob who has a fully fledged quantum power without revealing her input, output, and algorithm. So far, blind quantum computation has been considered only for the circuit model and the measurement-based model. Here we consider the possibility and the limitation of blind quantum computation in the ancilla-driven model, which is a hybrid of the circuit and the measurement-based models.

  2. Kalman Filtering Approach to Blind Equalization

    DTIC Science & Technology

    1993-12-01

    Update weighing probabilities (3.11) vi. Compute one step predictions p(j..Nb I X’) S(tlp (D,.,,,IX,) B. ADMISSIBILITY OF THE BLIND EQUALIZATION BY...NAVAL POSTGRADUATE SCHOOL Monterey, California •GR AD13 DTIC 94-07381 AR 0C199 THESIS S 0 LECTE4u KALMAN FILTERING APPROACH TO BLIND EQUALIZATION by...FILTERING APPROACH 5. FUNDING NUMBERS TO BLIND EQUALIZATION S. AUTHOR(S) Mehmet Kutlu 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) S

  3. Thermal imaging aid for the blind.

    PubMed

    Hedin, D S; Seifert, G J; Dagnelie, G; Havey, G D; Knuesel, R J; Gibson, P L

    2006-01-01

    To explore the efficacy of using a far infrared thermal camera with a haptic display to assist blind people in identifying humans, we performed experiments with a prototype device on five low-vision (functionally blind) subjects. Infrared allows for easy detection of human shape due to typically high contrast in temperatures from a person against their surrounding environment. Infrared cameras can be made small and inexpensive with uncooled microbolometer technology. Our study showed a great willingness by the blind subjects to use such a device after a short training session and both successful and unsuccessful operation. Future work will further develop the technology and undertake more expansive testing.

  4. Blind extraction of exoplanetary spectra

    NASA Astrophysics Data System (ADS)

    Morello, Giuseppe; Waldmann, Ingo; Damiano, Mario; Tinetti, Giovanna

    2016-10-01

    In the last decade, remote sensing spectroscopy enabled characterization of the atmospheres of extrasolar planets. Transmission and emission spectra of tens of transiting exoplanets have been measured with multiple instruments aboard Spitzer and Hubble Space Telescopes as well as ground-based facilities, revealing the presence of chemical species in their atmospheres, and constraining their temperature and pressure profiles.Early analyses were somehow heuristic, leading to some controversies in the literature.A photometric precision of 0.01% is necessary to detect the atmospheric spectral modulations. Current observatories, except Kepler, were not designed to achieve this precision. Data reduction is necessary to minimize the effect of instrument systematics in order to achieve the target precision. In the past, parametric models have extensively been used by most teams to remove correlated noise with the aid of auxiliary information of the instrument, the so-called optical state vectors (OSVs). Such OSVs can include inter- and intra-pixel position of the star or its spectrum, instrument temperatures and inclinations, and/or other parameters. In some cases, different parameterizations led to discrepant results.We recommend the use of blind non-parametric data detrending techniques to overcome those issues. In particular, we adopt Independent Component Analysis (ICA), i.e. a powerful blind source separation (BSS) technique to disentangle the multiple instrument systematics and astrophysical signals in transit/eclipse light curves. ICA does not require a model for the systematics, thence it can be applied to any instrument with little changes, if any. ICA-based algorithms have been applied to Spitzer/IRAC and synthetic observations in photometry (Morello et al. 2014, 2015, 2016; Morello 2015) and to Hubble/WFC3, Hubble/NICMOS and Spitzer/IRS and Hubble/WFC3 in spectroscopy (Damiano, Morello et al., in prep., Waldmann 2012, 2014, Waldmann et al. 2013) with excellent

  5. Blind extraction of exoplanetary spectra

    NASA Astrophysics Data System (ADS)

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

    2016-06-01

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

  6. Isolation and genetic characterisation of Toxoplasma gondii from a red-handed howler monkey (Alouatta belzebul), a jaguarundi (Puma yagouaroundi), and a black-eared opossum (Didelphis aurita) from Brazil.

    PubMed

    Pena, H F J; Marvulo, M F V; Horta, M C; Silva, M A; Silva, J C R; Siqueira, D B; Lima, P-A C P; Vitaliano, S N; Gennari, S M

    2011-02-10

    Toxoplasma gondii isolates are highly diverse in domestic animals from Brazil. However, little is known about the genetics of this parasite from wild mammals in the same region. Reveal genetic similarity or difference of T. gondii among different animal populations is necessary for us to understand transmission of this parasite. Here we reported isolation and genetic characterisation of three T. gondii isolates from wild animals in Brazil. The parasite was isolated by bioassay in mice from tissues of a young male red handed howler monkey (Alouatta belzebul), an adult male jaguarundi (Puma yagouaroundi), and an adult female black-eared opossum (Didelphis aurita). The monkey and the jaguarundi had inhabited the Zoo of Parque Estadual Dois Irmãos, Pernambuco State, Northeastern Brazil, for 1 year and 8 years, respectively. The wild black-eared opossum was captured in São Paulo State, Southeastern Brazil, and euthanised for this study because it was seropositive for T. gondii (titre 1:100 by the modified agglutination test, MAT). Ten PCR-RFLP (Polymerase Chain Reaction-Restriction Fragment Length Polymorphism) markers, SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico, were used to genotype the isolates. T. gondii was isolated from the brain and heart homogenate of the monkey, the muscle homogenate of the jaguarundi, and the heart homogenate of the black-eared opossum. This was the first isolation of T. gondii from a neotropical felid from Brazil. The isolate from the monkey (TgRhHmBr1) was not virulent in mice, whereas the isolates from the jaguarundi (TgJagBr1) and the black-eared opossum (TgOpBr1) were virulent in mice. The genotype of the isolate from the monkey has been identified in isolates from a goat and ten chickens in the same region of Brazil, suggesting that it may be a common lineage circulating in this region. The genotypes of the isolates from the jaguarundi and the black-eared opossum have not been previously reported. Although there

  7. Psychosocial implications of blindness and low vision in students of a school for children with blindness

    PubMed Central

    Ishtiaq, Rizwan; Chaudhary, Muhammad Hamid; Rana, Muhammad Atif; Jamil, Abdur Rehman

    2016-01-01

    Objective: To find out the psychosocial implications of blindness and low vision in students of blind school Bahawalpur. Methods: A cross sectional descriptive study was carried out in Higher Secondary School for blind, Bahawalpur after getting approval from Institutional review board of Quaid-e-Azam Medical College, Bahawalpur and Principal of Blind School, Bahawalpur. Forty willing students filled a customized questionnaire, consisting of questions about logistic variables and questions regarding areas of satisfaction. Statistical analysis was performed using SPSS version 18. Results: Out of 40, 55% (22/40) of them were found depressed (as assessed through DSM-lV), 50% (20/40) were having difficulty in making new contact but 52.5% (21/40) were satisfied with family care. Conclusion: Sixty percent (24/40) of blind school children experienced difficulty in their life. This study showed that blindness or low vision does have psychological implications like feeling of guilt, anxiety, sadness & depression. PMID:27182255

  8. HIV/AIDS and blindness.

    PubMed Central

    Kestelyn, P. G.; Cunningham, E. T.

    2001-01-01

    Nearly 34 million people are currently living with HIV/AIDS: ocular complications are common, affecting 50% to 75% of all such patients at some point during the course of their illness. Cytomegalovirus retinitis is by far the most frequent cause of vision loss in patients with AIDS. Although the prevalence of cytomegalovirus retinitis is decreasing in industrialized countries because of the widespread availability of highly active antiretroviral therapy, between 10% and 20% of HIV-infected patients worldwide can be expected to lose vision in one or both eyes as a result of ocular cytomegalovirus infection. Less frequent but important causes of bilateral vision loss in patients with HIV/AIDS include varicella zoster virus and herpes simplex virus retinitis, HIV-related ischaemic microvasculopathy, ocular syphilis, ocular tuberculosis, cryptococcal meningitis, and ocular toxic or allergic drug reactions. At present, most patients with HIV/AIDS in developing countries who lose their vision have a very limited life expectancy. As antiretroviral therapy makes its way to these countries, however, both life expectancy and the prevalence of blindness related to HIV/AIDS can be expected to increase dramatically. PMID:11285664

  9. Blindness of Johann Sebastian Bach.

    PubMed

    Tarkkanen, Ahti

    2013-03-01

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

  10. Blind estimation of reverberation time

    NASA Astrophysics Data System (ADS)

    Ratnam, Rama; Jones, Douglas L.; Wheeler, Bruce C.; O'Brien, William D.; Lansing, Charissa R.; Feng, Albert S.

    2003-11-01

    The reverberation time (RT) is an important parameter for characterizing the quality of an auditory space. Sounds in reverberant environments are subject to coloration. This affects speech intelligibility and sound localization. Many state-of-the-art audio signal processing algorithms, for example in hearing-aids and telephony, are expected to have the ability to characterize the listening environment, and turn on an appropriate processing strategy accordingly. Thus, a method for characterization of room RT based on passively received microphone signals represents an important enabling technology. Current RT estimators, such as Schroeder's method, depend on a controlled sound source, and thus cannot produce an online, blind RT estimate. Here, a method for estimating RT without prior knowledge of sound sources or room geometry is presented. The diffusive tail of reverberation was modeled as an exponentially damped Gaussian white noise process. The time-constant of the decay, which provided a measure of the RT, was estimated using a maximum-likelihood procedure. The estimates were obtained continuously, and an order-statistics filter was used to extract the most likely RT from the accumulated estimates. The procedure was illustrated for connected speech. Results obtained for simulated and real room data are in good agreement with the real RT values.

  11. Reversible cortical blindness after lung transplantation.

    PubMed

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

    2003-06-01

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

  12. Transient cortical blindness after coronary angiography.

    PubMed

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

    2009-01-01

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

  13. Iterated Gate Teleportation and Blind Quantum Computation.

    PubMed

    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.

  14. Iterated Gate Teleportation and Blind Quantum Computation

    NASA Astrophysics Data System (ADS)

    Pérez-Delgado, Carlos A.; Fitzsimons, Joseph F.

    2015-06-01

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

  15. Florida's Industrial Training Laboratory for Blind Persons

    ERIC Educational Resources Information Center

    Hoskins, Len

    1974-01-01

    Described is the 6-month program of the Industrial Training Laboratory (Florida) that has graduated 50 blind persons in 5 years and has enabled 48 of the graduates to hold full-time competitive jobs. (Author/MC)

  16. The Blind, From Braille to the Present.

    ERIC Educational Resources Information Center

    Truquet, Monique

    1980-01-01

    Traces the historical development of processing information for the blind from the system devised by Barbier to present systems of producing Braille documents using computers. Cites the impact of microprocessors and outlines possibilities for Braille reproductions in the future. (GS)

  17. Imagery limitations in totally congenitally blind subjects.

    PubMed

    De Beni, R; Cornoldi, C

    1988-10-01

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

  18. Teaching Introductory Statistics to Blind Students

    ERIC Educational Resources Information Center

    Marson, Stephen M.; Harrington, Charles F.; Walls, Adam

    2013-01-01

    The challenges of learning statistics, particularly distributions and their characteristics, can be potentially monumental for vision impaired and blind students. The authors provide some practical advice for teaching these students.

  19. Embodiment awareness, mathematics discourse, and the blind.

    PubMed

    Quek, Francis; McNeill, David

    2006-12-01

    Blindness might be described as a biological condition, and thus remedies could be in the realm of biotechnology. However, the convergence of information technology and cognitive science offers great opportunities for understanding and helping blind children as they learn mathematics, the crosscutting discipline most important for all branches of science and engineering. This article outlines our logic and approach for providing blind students with awareness of the embodiment of their teachers to maintain situated communication. First, we shall show that math discourse is inherently spatiotemporal, and that this information is carried by gesticulation in conjunction with speech. Second, we shall explore the capacity of those who are blind for the imagism necessary for mathematics reasoning. Third, we shall advance a set of augmentative devices suggested by our analysis. Finally, we shall outline our ongoing experiments to validate our rationale.

  20. Causes of blindness in children in the blind schools of Ethiopia.

    PubMed

    Wolde-Gebriel, Z; Gebru, H; West, C E

    1992-01-01

    A total of 721 children in the six schools for the blind in Ethiopia were studied. In 1988-1989 histories were taken to ascertain the predisposing factors and ophthalmological examinations and records were used to determine the causes of blindness. Ninety-five per cent of those examined had bilateral blindness, 12% did not know how they had become blind and, of those who provided information on how they became blind, 21% knew that they were born blind, 30% implicated measles as being responsible, and 13% implicated 'mitch' which is an Amharic term used to describe a very wide range of nonspecific and vague illnesses of which measles probably constitutes a significant proportion. Seventy per cent of the blindness was due to either corneal opacity or phthisis bulbi. Of those with non-congenital bilateral corneal opacity or phthisis bulbi, 40% were preceded by measles and 17% by mitch. A study of 66 adults in the handicraft and skill-training centres attached to the blind schools indicated that the principal predisposing factors of blindness were mitch (30%), smallpox (15%), cataract (12%), and traditional eye medicine (11%). Seventy percent had corneal scars of phthisis bulbi and 14% cataract.

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

    PubMed Central

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

    2016-01-01

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

  2. 42 CFR 436.530 - Definition of blindness.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 4 2013-10-01 2013-10-01 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...

  3. 42 CFR 435.530 - Definition of blindness.

    Code of Federal Regulations, 2010 CFR

    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,...

  4. 42 CFR 436.530 - Definition of blindness.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 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...

  5. 42 CFR 436.530 - Definition of blindness.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 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...

  6. 42 CFR 435.530 - Definition of blindness.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 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,...

  7. 42 CFR 436.530 - Definition of blindness.

    Code of Federal Regulations, 2010 CFR

    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...

  8. 42 CFR 435.530 - Definition of blindness.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 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,...

  9. 42 CFR 435.530 - Definition of blindness.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 4 2013-10-01 2013-10-01 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,...

  10. 42 CFR 436.530 - Definition of blindness.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 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...

  11. 42 CFR 435.530 - Definition of blindness.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 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,...

  12. Multiply-Impaired Blind Children: A National Problem.

    ERIC Educational Resources Information Center

    Graham, Milton D.

    In 1966, a national survey reported on 8,887 multiply impaired (MI) blind children. About 56% were boys; 85% had been blind since before age 3, and half were totally blind. The principal causes of blindness were retrolental fibroplasia and congenital cataracts. Almost 63% had two or more additional disabilities (86.8% of those under age 6), such…

  13. Programs for Deaf-Blind Children and Adults.

    ERIC Educational Resources Information Center

    American Annals of the Deaf, 1995

    1995-01-01

    This report of the annual survey of programs for deaf-blind children and adults lists, by state, programs for deaf-blind children and youth, Helen Keller Centers for deaf-blind youth and adults, and programs for training teachers of deaf-blind students. Provided are program names, addresses, telephone numbers, and names of directors. (DB)

  14. Programs for Deaf-Blind Children and Adults.

    ERIC Educational Resources Information Center

    American Annals of the Deaf, 2000

    2000-01-01

    This annual directory lists programs for deaf-blind children and adults including programs for deaf-blind children and youth (national and state level), the Helen Keller Centers for deaf-blind youth and adults, and programs for training teachers of deaf-blind students. (DB)

  15. Astronomy for the Blind and Visually Impaired

    NASA Astrophysics Data System (ADS)

    Kraus, S.

    2016-12-01

    This article presents a number of ways of communicating astronomy topics, ranging from classical astronomy to modern astrophysics, to the blind and visually impaired. A major aim of these projects is to provide access which goes beyond the use of the tactile sense to improve knowledge transfer for blind and visually impaired students. The models presented here are especially suitable for young people of secondary school age.

  16. Shape Perception and Navigation in Blind Adults

    PubMed Central

    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

  17. Shape Perception and Navigation in Blind Adults.

    PubMed

    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.

  18. Prevention of Blindness in the USSR.

    ERIC Educational Resources Information Center

    Trutneva, K.

    The booklet describes approaches used in the Union of Soviet Socialist Republics to prevent blindness. It contrasts conditions prior to 1917 (300 eye doctors mainly located in large cities and 2,000 hospital beds for the 300,000 totally blind and 7,000,000 people with trachoma) with conditions in 1971 when in the Ukraine alone there were 3,000 eye…

  19. [Temporary blindness after transnasal ethmoidectomy (author's transl)].

    PubMed

    Langnickel, R

    1978-05-01

    A unilateral blindness after transnasal ethmoidectomy was diagnosed postoperatively while the patient was still in theatre. Exploration via an external approach was performed immediately, a haematoma was drained and the posteroir ethmoid artery was cauterized. This led to a recovery of vision. The temporary blindness was probably due to increased intraorbital pressure by the retrobulbar haematoma which led to stretching of and pressure on the optic nerve.

  20. Unblinding the dark matter blind spots

    DOE PAGES

    Han, Tao; Kling, Felix; Su, Shufang; ...

    2017-02-10

    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 relicmore » 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.« less

  1. Unblinding the dark matter blind spots

    NASA Astrophysics Data System (ADS)

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

    2017-02-01

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

  2. Prevalence of colour blindness in young Jordanians.

    PubMed

    Al-Aqtum, M T; Al-Qawasmeh, M H

    2001-01-01

    Colour blindness is one of the common genetic disorders observed in all human populations. It is a sex-linked recessive trait. The genes are located on the X chromosome within the Xq28 band. 1,418 university students (1,200 female and 218 male) from Zarka Private University and the Hashemite University were randomly selected and tested for congenital red/green colour blindness, by using Ishihara pseudo-isochromatic colour plates. A total of 23 individuals were found to be colour blind. In females, 4 students (0.33%) were colour blind: 1 of them showed protanomalia, 1 protanopia and 2 deuteranomalia. In males, 19 students (8.72%) were colour blind: 4 showed protanomalia, 3 protanopia, 8 deuteranomalia and 4 deuteranopia. The allelic frequencies of the colour vision gene were found to be 0.087 in males, 0.003 in females and 0.016 in the total population. Studies on colour blindness in Jordan are very few; this population-based investigation is meant to fill a gap in this field.

  3. 75 FR 47304 - Accessible Mobile Phone Options for People Who Are Blind, Deaf-Blind, or Have Low Vision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-05

    ... COMMISSION Accessible Mobile Phone Options for People Who Are Blind, Deaf- Blind, or Have Low Vision AGENCY...-145, which shall be captioned ``Accessible Mobile Phone Options for People who are Blind, Deaf-blind... following issues: The wireless phone features and functions in the current marketplace that are...

  4. Changes in blindness prevalence over 16 years in Malawi: reduced prevalence but increased numbers of blind

    PubMed Central

    Courtright, P; Hoeshcmann, A; Metcalfe, N; Chirambo, M; Noertjojo, K; Barrows, J; Katz, J

    2003-01-01

    Background/aims: In the coming two decades significant increases in the burden of blindness are anticipated unless concerted efforts are made to improve eye care in developing countries. Evidence of changing prevalence rates or numbers of blind people are few. The change in blindness prevalence and the number of blind people in an adult population of Malawi was measured over a 16 year period. Methods: In 1999 a population based survey of blindness in adults (age 50+) was conducted in Chikwawa district of Malawi. Visual acuity and cause of vision loss were recorded for each eye independently. Blindness was defined as presenting better eye vision of <6/60. Findings from a 1983 survey of blindness in the same district (using similar methods) were re-analysed to be comparable with the survey conducted in 1999. Results: Among 1630 enumerated adults 89% were examined. The age adjusted prevalence of blindness in the adult population was 5.4% and more common in women than men. In each age group the prevalence of blindness was lower in 1999 than in 1983; the overall reduction in blindness was 31%. During this period the 50+ population in Malawi increased almost twofold. Extrapolating the Chikwawa district data to the Malawi population reveals that the number of blind people has increased by 24%; the increase is primarily because of the large increase in the size of the most elderly group, aged 70 and above. Conclusion: The majority of blind people in Chikwawa (1983 and 1999) are in the age group 70 and over. This group has had the largest proportional increase in population size in this time. Services in this population have improved in the intervening 16 years and yet there was still an increase in the number of blind people. There was little change in excess blindness in women, suggesting that the same barriers that prevented utilisation of services in 1983 probably persist in 1999. Efforts to reach the most elderly and to reach women are needed to lead to a reduction in

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

    ERIC Educational Resources Information Center

    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…

  6. Our Blind Child: Bringing Up a Blind Child During Its Early Years.

    ERIC Educational Resources Information Center

    Pielasch, Helmut, Ed.; And Others

    The document contains 10 author contributed chapters (in four languages) which resulted from a 1976 international symposium on problems concerning the preschool education of blind children and the guidance of their parents. Chapters have the following titles (with authors and nationality in parentheses): "Development of the Blind Child"…

  7. Blind topological measurement-based quantum computation.

    PubMed

    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.

  8. Experimental demonstration of blind quantum computing

    NASA Astrophysics Data System (ADS)

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

    2012-02-01

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

  9. A Novel Quantum Proxy Blind Signature Scheme

    NASA Astrophysics Data System (ADS)

    Guo, Wei; Xie, Shu-Cui; Zhang, Jian-Zhong

    2017-02-01

    A novel quantum proxy blind signature scheme is proposed. In this scheme, a special type of non-maximally entangled three-qubit state is introduced as a quantum channel, which can realize perfect teleportation. The message sender U blinds his message by means of preparing two groups of non-orthogonal single-photon states. According to the original signer Charlie's delegation message, the proxy signer Alice generates a corresponding signature. The arbitrator Trent can help the receiver Bob verify the signature, and also prevent Bob from doing any damage. The above-mentioned advantages make this scheme different from some existing schemes. It is showed that our scheme has the properties of undeniability, unforgeability, blindness, untraceability. Moreover, it is free from intercept-resend attack.

  10. Patient-physician communication when blindness threatens.

    PubMed

    Hopper, S V; Fischbach, R L

    1989-08-01

    The threat of blindness creates a difficult and challenging environment for communication between patients and their ophthalmologists. This study examined concordance between what patients want to know from their physicians about their eye condition and what physicians believe their patients need to know. Eight retinal specialists and 24 of their patients with proliferative diabetic retinopathy and at risk of blindness were interviewed using parallel-constructed instruments. Although all recognized that blindness was the patients' greatest concern, disparities were noted that involved the desire/need to know about the possibility of vision loss, the causes of the eye condition, the results of each eye exam, and the extent of patient confusion. Physicians, while conscientious about informed consent, described various communication behaviors to avoid discussing bad news.

  11. Blinding trachoma: prevention with the safe strategy.

    PubMed

    West, Sheila K

    2003-11-01

    Trachoma, the second leading cause of blindness worldwide, differentially affects the poorest communities, which may have the least access to resources. With the establishment of the Global Elimination of Blinding Trachoma by 2020 (GET 2020) goal, the World Health Organization has set an ambitious target for country programs. The currently recommended surgery for trichiasis/entropion, antibiotics for active disease, facial cleanliness, and environmental change to reduce transmission (SAFE) strategy targets all key elements believed to be necessary for a short- and long-term intervention program. This report reviews the need for a multi-faceted strategy, and the evidence supporting the elements of SAFE. Concerns about the implementation are discussed. Additional research is suggested that will enhance the implementation of the SAFE strategy. In the current climate of significant political and social momentum for trachoma control, the SAFE strategy is a safe bet to accomplish the elimination of blinding trachoma.

  12. Brief mindfulness induction reduces inattentional blindness.

    PubMed

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

    2015-12-01

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

  13. Parallelization of a blind deconvolution algorithm

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed

    Weisleder, Pedro

    2012-06-01

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

  15. Contrast-induced transient cortical blindness.

    PubMed

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

    2013-05-01

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

  16. Analysis of clinical data with breached blindness.

    PubMed

    Chow, Shein-Chung; Shao, Jun

    2004-04-30

    In clinical trials, blinding is usually employed to prevent bias that may be introduced due to the knowledge of the identity of the treatment codes. This bias could alter the conclusion of statistical inference on the treatment effect. The purpose of this article is to propose a method for analysing clinical data with breached blindness. The example regarding the study of the effectiveness of an appetite suppressant in weight loss in obese woman as described in Brownell and Stunkard (Am. J. Psychiatry 1982; 139:1487-1489) is used to illustrate the application of the proposed methods.

  17. Transform domain steganography with blind source separation

    NASA Astrophysics Data System (ADS)

    Jouny, Ismail

    2015-05-01

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

  18. Research on solar-blind UV optical imaging system

    NASA Astrophysics Data System (ADS)

    Wang, Baohua; Wang, Yuanyuan; Zhong, Xiaoming; Ruan, Ningjuan

    2015-02-01

    Solar blind UV detecting system has many advantages such as strong environmental adaptability, low error rate, small volume and without refrigeration. To in-depth develop UV solar blind detection system research work has important significance for further improving solar blind UV detection technology. The working principle of solar blind UV detection system and the basic components were introduced firstly, and then the key technology of solar blind UV detection system was deeply analyzed. Finally, large coverage solar blind UV optical imaging system was designed according to the actual demand for greater coverage of the solar blind UV detection system. The result shows that the system has good imaging quality, simple and compact structure. This system can be used in various types of solar blind UV detection system, and is of high application value.

  19. Brain 'Rewires' to Work Around Early-Life Blindness

    MedlinePlus

    ... html Brain 'Rewires' to Work Around Early-Life Blindness These differences appear to boost hearing, smell and ... 22, 2017 WEDNESDAY, March 22, 2017 (HealthDay News) -- Blindness at an early age triggers the brain to ...

  20. Men and antiretroviral therapy in Africa: our blind spot.

    PubMed

    Cornell, Morna; McIntyre, James; Myer, Landon

    2011-07-01

    Most antiretroviral therapy (ART)-related policies remain blind to men's treatment needs. Global and national programmes need to address this blindness urgently, to ensure equitable access to ART in Africa.

  1. Blind College Students--Counseling and Guidance Approaches

    ERIC Educational Resources Information Center

    Dailey, Louise

    1977-01-01

    This article discusses the personal, academic, mechanical, and placement support needed by blind college students. Financial, community, and commercial resources are identified, and suggestions are offered to counselors for developing programs that enhance faculty sensitivity and blind student development. (Author)

  2. Concepts about Print for the Young Blind Child.

    ERIC Educational Resources Information Center

    Language Arts, 1982

    1982-01-01

    Provides teachers with an understanding of how sighted children develop concepts about print and how blind children develop concepts about braille. Prereading activities designed to extend young children's concepts about print are adapted for blind children. (HTH)

  3. Blind Quantum Computing with Weak Coherent Pulses

    NASA Astrophysics Data System (ADS)

    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.

  4. Audiological Assessment of Deaf-Blind Children.

    ERIC Educational Resources Information Center

    Bernstein, Phyllis F.; Roeser, Ross J.

    The audiological assessment of 50 deaf blind children, 6 months to 14 years of age, in an outpatient setting is described, as are testing procedures and results. Etiological factors are given which include maternal rubella (accounting for 27 children), meningitis, prematurity, neonatal anoxia, and Rh incompatability. Discussed are the following…

  5. Drilling at right angles in blind holes

    NASA Technical Reports Server (NTRS)

    Pessin, R.

    1981-01-01

    Tool drills small hole perpendicular to and at bottom of blind hole. It consists of carbide cutter brazed to flexible shaft, inside thin metal tube with 90 degree bend. Wood dowel holds tube while motor turns shaft and drives cutter. It was developed for clearing plugged fuel orifices. Concept is adaptable to other hard-to-reach drilling situations.

  6. Functional rehabilitation of partial cortical blindness?

    PubMed

    Stoerig, Petra

    2008-01-01

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

  7. Blind quantum computing with weak coherent pulses.

    PubMed

    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.

  8. Graphic Biology Laboratory Modules for the Blind.

    ERIC Educational Resources Information Center

    Brooks, Austin E.

    The goal of this project was to devise new methods of producing tactile facsimiles of microscopic images for the blind and visually impaired biology students at the secondary and college level. The numerous raised-line images that were produced were assembled along with brailled and large print student instructions, audio cassette tapes describing…

  9. What Art Three Blind Mice Up To?

    ERIC Educational Resources Information Center

    Peace, Suze

    1998-01-01

    Offers an integrated art lesson in which kindergarten students drew a picture in response to the "Three Blind Mice" using geometric shapes for the mice. Summarizes the technique used to create the mice and focuses on mixing colors to introduce tints and shading to the students. (CMK)

  10. Deaf-Blind Perspectives, 2001-2002.

    ERIC Educational Resources Information Center

    Malloy, Peggy, Ed.

    2002-01-01

    Three issues of this newsletter on deaf-blind issues include announcements, reviews, news items, and the following articles: "'What's My Role?' A Comparison of the Responsibilities of Interpreters, Interveners, and Support Service Providers" (Susanne Morgan); "A Support Service Provider Program in Utah" (Cordie Weed);…

  11. Why Art Education for the Elderly Blind?

    ERIC Educational Resources Information Center

    Aspell, Amy S.

    1976-01-01

    Identification and analysis of types of problems blind populations encounter, through literature on the topic and observation, leads one to the unexpected conclusion that art can play an essential role in the amelioration of these problems. Art and craft activities can provide a process of self-analysis for therapy toward adjustment. (Author)

  12. Expert Blind Spot among Preservice Teachers

    ERIC Educational Resources Information Center

    Nathan, Mitchell J.; Petrosino, Anthony

    2003-01-01

    This study (N = 48) examined the relationship between preservice secondary teachers' subject-matter expertise in mathematics and their judgments of students' algebra problem-solving difficulty. As predicted by the "expert blind spot" hypothesis, participants with more advanced mathematics education, regardless of their program affiliation or…

  13. Deaf Blind Children: Evaluating Their Multiple Handicaps.

    ERIC Educational Resources Information Center

    Curtis, Scott, Ed.; And Others

    Prepared by specialists on the evaluation team at the Syracuse University Center for the Development of Blind Children, the book describes the procedures of the special diagnostic clinic within this unit. The diagnostic clinic was established to provide a unified approach to the evaluation and study of multiply handicapped children. Described in…

  14. Postural Determinants in the Blind. Final Report.

    ERIC Educational Resources Information Center

    Siegel, Irwin M.; Murphy, Thomas J.

    The problem of malposture in the blind and its affect on orientation and travel skills was explored. A group of 45 students were enrolled in a standard 3-month mobility training program. Each student suffered a postural problem, some compounded by severe orthopedic and/or neurological deficit. All subjects were given complete orthopedic and…

  15. Cognitive Development in Deaf-Blind Children.

    ERIC Educational Resources Information Center

    Rittenhouse, Robert K.

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

  16. Environmental Programming for the Deaf-Blind.

    ERIC Educational Resources Information Center

    Michigan School for the Blind, Lansing.

    Presented are the proceedings of an environmental programing workshop on deaf blind individuals at which principles, techniques, and examples of behavior modification were discussed and demonstrated. Rules for data collection are given as well as explanations of the categorizing, the measuring devices, and the data sheets involved in behavior…

  17. Mobility and Orientation Instruction of Blind Persons.

    ERIC Educational Resources Information Center

    Luini, Eugene; Ryder, James

    A peripatologist taught 102 blind and partially sighted individuals of all ages mobility and orientation techniques. Volunteers assisted with transportation, followup, consultation, and direct teaching of mobility. Over a 3-year period, the number of lessons per client varied from one to 86, and the number of hours spent by the instructor in…

  18. Does semantic preactivation reduce inattentional blindness?

    PubMed

    Kreitz, Carina; Schnuerch, Robert; Furley, Philip A; Gibbons, Henning; Memmert, Daniel

    2015-04-01

    We are susceptible to failures of awareness if a stimulus occurs unexpectedly and our attention is focused elsewhere. Such inattentional blindness is modulated by various parameters, including stimulus attributes, the observer's cognitive resources, and the observer's attentional set regarding the primary task. In three behavioral experiments with a total of 360 participants, we investigated whether mere semantic preactivation of the color of an unexpected object can reduce inattentional blindness. Neither explicitly mentioning the color several times before the occurrence of the unexpected stimulus nor priming the color more implicitly via color-related concepts could significantly reduce the susceptibility to inattentional blindness. Even putting the specific color concept in the main focus of the primary task did not lead to reduced inattentional blindness. Thus, we have shown that the failure to consciously perceive unexpected objects was not moderated by semantic preactivation of the objects' most prominent feature: its color. We suggest that this finding reflects the rather general principle that preactivations that are not motivationally relevant for one's current selection goals do not suffice to make an unexpected object overcome the threshold of awareness.

  19. Pattern Perception and Pictures for the Blind

    ERIC Educational Resources Information Center

    Heller, Morton A.; McCarthy, Melissa; Clark, Ashley

    2005-01-01

    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…

  20. Default brain functionality in blind people.

    PubMed

    Burton, H; Snyder, A Z; Raichle, M E

    2004-10-26

    We studied whether default functionality of the human brain, as revealed by task-independent decreases in activity occurring during goal-directed behaviors, is functionally reorganized by blindness. Three groups of otherwise normal adults were studied: early blind, adventitiously blind, and normally sighted. They were imaged by using functional MRI during performance of a word association task (verb generation to nouns) administered by using auditory stimuli in all groups and Braille reading in blind participants. In sighted people, this task normally produces robust task-independent decreases relative to a baseline of quiet wakefulness with eyes closed. Our functional MRI results indicate that task-independent decreases are qualitatively similar across all participant groups in medial and dorsal prefrontal, lateral parietal, anterior precuneus, and posterior cingulate cortices. Similarities in task-independent decreases are consistent with the hypothesis that functional reorganization resulting from the absence of a particular sensory modality does not qualitatively affect default functionality as revealed by task-independent decreases. More generally, these results support the notion that the brain largely operates intrinsically, with sensory information modulating rather than determining system operations.

  1. My Blindness? No More than an Inconvenience

    ERIC Educational Resources Information Center

    Weller, Jamie

    2005-01-01

    A blind ex-service man gives an account of the onset of cone dystrophy which brought an end to his career as an aircraft engineer. He tells of his rehabilitation and training in residential settings, of the acquisition of new skills, and of studying to gain a bachelor's degree, and of setting out on an entirely new professional career. What…

  2. Terminology and the Psychosocial Burden of Blindness

    ERIC Educational Resources Information Center

    Bolt, David

    2004-01-01

    Various denotations and connotations of the word "blindness" are examined and the inference is drawn that they constitute a psychosocial burden that perpetuates prejudice. The analysis leads on to a hypothesis in which a more progressive terminology could lead to reduction of this burden.

  3. [Recreation for Youth with Deaf Blindness.

    ERIC Educational Resources Information Center

    Carr, Theresa, Ed.

    1992-01-01

    This newsletter special issue focuses on recreational programming for people with deaf blindness. The following individual articles are presented: "Strategies To Promote Community Integrated Recreation: Guidelines for Leisure Coaches" by Joann Enos (which lists seven such strategies); "Assessing Recreation and Leisure…

  4. Potentials of Rubella Deaf-Blind Children.

    ERIC Educational Resources Information Center

    Smith, Benjamin F.

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

  5. 47 CFR 64.610 - Establishment of a National Deaf-Blind Equipment Distribution Program.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., blind or deaf-blind; or private entities, including but not limited to, organizational affiliates...-blindness, including familiarity with the culture and etiquette of people who are deaf-blind, to ensure...

  6. 47 CFR 64.610 - Establishment of a National Deaf-Blind Equipment Distribution Program.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., blind or deaf-blind; or private entities, including but not limited to, organizational affiliates...-blindness, including familiarity with the culture and etiquette of people who are deaf-blind, to ensure...

  7. 47 CFR 64.610 - Establishment of a National Deaf-Blind Equipment Distribution Program.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., blind or deaf-blind; or private entities, including but not limited to, organizational affiliates...-blindness, including familiarity with the culture and etiquette of people who are deaf-blind, to ensure...

  8. 47 CFR 64.610 - Establishment of a National Deaf-Blind Equipment Distribution Program.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., blind or deaf-blind; or private entities, including but not limited to, organizational affiliates...-blindness, including familiarity with the culture and etiquette of people who are deaf-blind, to ensure...

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

    ERIC Educational Resources Information Center

    Pringle, Doug; Winthers, Jim

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

  10. Programs for Deaf-Blind Children and Adults.

    ERIC Educational Resources Information Center

    American Annals of the Deaf, 1999

    1999-01-01

    This directory of programs for deaf-blind children and adults lists program name, address, telephone numbers, e-mail address, Web site, and administrator name. The directory also lists, with similar information, Helen Keller Centers for Deaf-Blind Youth and Adults, and programs for training teachers of deaf-blind students. (DB)

  11. THE SELECTION, TRAINING, AND PLACEMENT OF BLIND COMPUTER PROGRAMMERS.

    ERIC Educational Resources Information Center

    Kansas State Univ., Manhattan.

    FINDINGS OF A 2-YEAR STUDY ON THE SELECTION, TRAINING, AND EMPLOYMENT OF BLIND PERSONS IN THE COMPUTER RELATED PROFESSIONS ARE REPORTED FOR USE AS A GUIDE FOR THE TEACHER OF COMPUTER PROFESSIONALS, THE EMPLOYER WHO SEEKS TO MAKE USE OF EMPLOYEES' SKILLS, THE REHABILITATION WORKER WHO WILL GUIDE THE BLIND PERSON, AND THE BLIND PERSON WHO CHOOSES…

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

    ERIC Educational Resources Information Center

    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…

  13. 34 CFR 395.11 - Training program for blind individuals.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

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

  14. Recreation for Blind Adults. Organized Programs in Specialized Settings.

    ERIC Educational Resources Information Center

    Case, Maurice

    The effects of blindness in adults, activity programs, and the administrative technicalities of these programs are discussed. A definition of blindness, historical background, and mention of social group work serve as introduction to the impact of blindness. Under these activities are included the following subjects: arts and crafts, study and…

  15. 10 CFR 26.168 - Blind performance testing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... the blind performance test samples submitted to the laboratory must be positive for one or more drugs... blind performance test samples to the HHS-certified laboratory. (1) During the initial 90-day period of... licensee or other entity shall submit blind performance test samples to each HHS-certified laboratory...

  16. Raising the Welfare of the Blind in the USSR.

    ERIC Educational Resources Information Center

    Zimin, B.

    Described are activities and plans of the All-Russia Society for the Blind. Noted is the changing composition of society membership in the direction of more members past 60 years of age and fewer children blinded at birth or early childhood. It is reported that all the blind who wish work are employed, and that the society provides professional…

  17. Programs for Deaf-Blind Children and Adults.

    ERIC Educational Resources Information Center

    American Annals of the Deaf, 1998

    1998-01-01

    This directory of programs for deaf-blind children and adults lists these programs alphabetically by state. It also lists Helen Keller Centers for Deaf Blind Youth and Adults and programs for training teachers of deaf-blind students. Complete contact information (names, addresses, telephone numbers, e-mail, Web site) is provided. (DB)

  18. Programs for Deaf-Blind Children and Adults.

    ERIC Educational Resources Information Center

    American Annals of the Deaf, 1993

    1993-01-01

    The 1992-93 directory of programs for children and adults with deaf-blindness lists (1) 27 state or multistate programs; (2) the national headquarters and the 10 regional offices of the Helen Keller National Center for Deaf Blind Youth and Adults; and (3) seven programs for training teachers of deaf blind students. (DB)

  19. Programs for Deaf-blind Children and Adults.

    ERIC Educational Resources Information Center

    American Annals of the Deaf, 2001

    2001-01-01

    This directory provides information on programs for deaf-blind children and adults including national and state programs, the Helen Keller Centers for Deaf-Blind Youth and Adults, and programs for training teachers of deaf-blind students. Within each broad category, programs are listed alphabetically by state and provide detailed contact…

  20. Programs for Deaf-Blind Children and Adults.

    ERIC Educational Resources Information Center

    American Annals of the Deaf, 1994

    1994-01-01

    This directory lists programs for deaf-blind children and youth, regional offices of the Helen Keller National Center for Deaf-Blind Youth and Adults, and programs for training teachers of deaf-blind students. Programs are listed alphabetically by state, with contact information provided. (DB)

  1. The feasibility of external blind DNA proficiency testing. II. Experience with actual blind tests.

    PubMed

    Peterson, Joseph L; Lin, George; Ho, Monica; Chen, Yingyu; Gaensslen, R E

    2003-01-01

    The background and goals of a national study to determine the feasibility of blind proficiency testing in U.S. forensic DNA laboratories are discussed. Part of the project involved designing and executing a series of fifteen blind proficiency tests. Execution included biological specimen donor recruitment and case evidence manufacturing. Simulated cases were submitted to DNA laboratories by law enforcement agencies and in some cases by other forensic-science laboratories. Replicate-manufactured evidence was submitted to reference laboratories to simulate the workings of a larger-scale program. Ten tests were straightforward, and essentially tested analytical ability. Five tests involved selecting on the basis of case facts appropriate bloodstains for typing from a bloodstain pattern. We describe in detail our experience in designing and conducting these blind proficiency test trials, and relate those experiences to the overall issue of blind proficiency testing as a quality-assurance tool in forensic DNA laboratories. In this feasibility test series, one blind test was detected by a laboratory, a second one was shown to the lab by law enforcement, and a third was never completed because of lapses in communication. Turnaround times were relatively fast in the independent/commercial labs and relatively slow in the larger public laboratories. Two cross-state case-to-case CODIS "hits" were "planted" among the first series of ten blind tests. One pair was detected. One member of the second pair went to a lab that was not CODIS-ready.

  2. 20 CFR 416.981 - Meaning of blindness as defined in the law.

    Code of Federal Regulations, 2010 CFR

    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...

  3. 20 CFR 416.981 - Meaning of blindness as defined in the law.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 2 2013-04-01 2013-04-01 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...

  4. 20 CFR 416.981 - Meaning of blindness as defined in the law.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 2 2012-04-01 2012-04-01 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...

  5. 20 CFR 416.981 - Meaning of blindness as defined in the law.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 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...

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

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false Meaning of blindness as defined in the law... INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Blindness § 416.981 Meaning of blindness as defined in the law. We will consider you blind under the law for payment...

  7. Blindness and intranasal endoscopic ethmoidectomy: prevention and management.

    PubMed

    Stankiewicz, J A

    1989-09-01

    Blindness is one of the major complications that can occur during and after intranasal ethmoidectomy. Two mechanisms for blindness are apparent: (1) direct injury to the optic nerve and (2) retrobulbar (orbital) hematoma, which increases orbital pressure and compromises vascular supply and drainage to and from the eye. While several publications have discussed the management of blindness from a delayed operative vantage point, no publication has discussed the immediate management of blindness from intraoperative or immediate postoperative occurrence, stressing specific medical and surgical treatment. A review of the literature and the author's personal experience will be used as a basis to discuss the prevention and management of blindness during endoscopic intranasal ethmoidectomy. Case studies will be used to illustrate methods for prevention and management of blindness. If treated aggressively, blindness associated with retrobulbar hematoma can be reversed medically.

  8. Relearning to See in Cortical Blindness.

    PubMed

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

    2016-04-01

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

  9. Permanent cortical blindness after bronchial artery embolization.

    PubMed

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

    2013-12-01

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

  10. Permanent Cortical Blindness After Bronchial Artery Embolization

    SciTech Connect

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

    2013-12-15

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

  11. Euro Banknote Recognition System for Blind People

    PubMed Central

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

    2017-01-01

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

  12. Kalman filtering approach to blind equalization

    NASA Astrophysics Data System (ADS)

    Kutlu, Mehmet

    1993-12-01

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

  13. Drawings from Gaia, a blind girl.

    PubMed

    Kennedy, John M

    2003-01-01

    Gaia, a totally blind girl, was asked to make raised-line drawings. Gaia's vision at best was peripheral. She draws out of interest, and has drawn since preschool with encouragement from her mother. She was asked to draw objects and scenes involving depth from a vantage point, eg a table from below, two cars (one behind the other), and two parallel rows of apples (receding from her, on a table top). Gaia represented space in her drawings using T-junctions for overlap, height in the picture plane, parallel projection, and inverse projection. That is, Gaia uses features of systems common in sighted children's drawings. The development of drawing in blind and sighted children may be similar in good measure because haptics provides access to many of the same spatial principles as vision.

  14. WHO celebrates triumph over river blindness.

    PubMed

    Ciment, J

    1999-10-23

    This article reports the success of WHO in eliminating onchocerciasis or river blindness in most of West Africa. The onchocerciasis control program was able to save 100,000 people at immediate risk of contracting the disease and prevented the infection of about 12 million children. About 1.25 million onchocercal infections have been resolved by the program. Moreover, removal of the threat of the disease has allowed people to farm 25 million hectares of fertile land capable of feeding 17 million people annually. The land was previously abandoned due to black fly infestations, the transmission vector of the disease. The control program, which was started 25 years ago, had successfully eliminated the disease after a partnership between the UN agency and Merck, the company that developed ivermectin. Ivermectin is the first drug against river blindness that could be dispensed widely without fear of serious side effects.

  15. Euro Banknote Recognition System for Blind People.

    PubMed

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

    2017-01-20

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

  16. Broadband Venetian Blind polarizer with dual vanes

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

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

  17. Dog models for blinding inherited retinal dystrophies.

    PubMed

    Petersen-Jones, Simon M; Komáromy, András M

    2015-03-01

    Spontaneous canine models exist for several inherited retinal dystrophies. This review will summarize the models and indicate where they have been used in translational gene therapy trials. The RPE65 gene therapy trials to treat childhood blindness are a good example of how studies in dogs have contributed to therapy development. Outcomes in human clinical trials are compared and contrasted with the result of the preclinical dog trials.

  18. Dog Models for Blinding Inherited Retinal Dystrophies

    PubMed Central

    Komáromy, András M.

    2015-01-01

    Abstract Spontaneous canine models exist for several inherited retinal dystrophies. This review will summarize the models and indicate where they have been used in translational gene therapy trials. The RPE65 gene therapy trials to treat childhood blindness are a good example of how studies in dogs have contributed to therapy development. Outcomes in human clinical trials are compared and contrasted with the result of the preclinical dog trials. PMID:25671556

  19. Measurement of Altitude in Blind Flying

    NASA Technical Reports Server (NTRS)

    Brombacher, W G

    1934-01-01

    In this note, instruments for measuring altitude and rate of change of altitude in blind flying and landing of aircraft and their performance are discussed. Of those indicating the altitude above ground level, the sonic altimeter is the most promising. Its present bulk, intermittent operation, and more or less unsatisfactory means of indication are serious drawbacks to its use. The sensitive type aneroid altimeter is also discussed and errors in flying at a pressure level and in landing are discussed in detail.

  20. Quantum Key Distribution with Blind Polarization Bases

    NASA Astrophysics Data System (ADS)

    Kye, Won-Ho; Kim, Chil-Min; Kim, M. S.; Park, Young-Jai

    2005-07-01

    We propose a new quantum key distribution scheme that uses the blind polarization basis. In our scheme the sender and the receiver share key information by exchanging qubits with arbitrary polarization angles without basis reconciliation. As only random polarizations are transmitted, our protocol is secure even when a key is embedded in a not-so-weak coherent-state pulse. We show its security against the photon-number splitting attack and the impersonation attack.

  1. Transient cortical blindness after coronary artery angiography.

    PubMed

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

    2013-01-01

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

  2. Blind deconvolution and source separation in acoustics

    NASA Astrophysics Data System (ADS)

    Sibul, Leon H.; Roan, Michael J.; Coviello, Christian M.

    2005-09-01

    Blind deconvolution (BDC) and blind source separation (BSS) are active research topics with many important applications in acoustics. The goal of deconvolution is to recover original input signal from the output of a convolution filter. In blind deconvolution details of the convolution filter and input signals are not known. The fundamental assumption in BDC is that the input signal is a non-Gaussian stochastic process. A topic closely related to BDC is BSS. BSS is a process that is an inverse operation to a mixing process. In BSS it is assumed that inputs to the mixing systems are statistically independent stochastic processes, where only one input may be Gaussian, others must be non-Gaussian. Standard criterion functions for BDC and BSS are reviewed. Limitations of the second-order statistics and need for higher-order statistics (HOS) or information theoretic criteria that lead to nonlinear optimization algorithms are pointed out. Advantages of various information theoretic criteria for BDC and BSS are discussed. Because gradients of these criteria are nonlinear, resulting optimization algorithms are nonlinear. Linear and non-linear algorithms for BDC and BSS are examined. [Work supported by ONR Codes 321US and 333.

  3. The spatiotopic 'visual' cortex of the blind

    NASA Astrophysics Data System (ADS)

    Likova, Lora

    2012-03-01

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

  4. When Emotion Blinds: A Spatiotemporal Competition Account of Emotion-Induced Blindness

    PubMed Central

    Wang, Lingling; Kennedy, Briana L.; Most, Steven B.

    2012-01-01

    Emotional visual scenes are such powerful attractors of attention that they can disrupt perception of other stimuli that appear soon afterward, an effect known as emotion-induced blindness. What mechanisms underlie this impact of emotion on perception? Evidence suggests that emotion-induced blindness may be distinguishable from closely related phenomena such as the orienting of spatial attention to emotional stimuli or the central resource bottlenecks commonly associated with the attentional blink. Instead, we suggest that emotion-induced blindness reflects relatively early competition between targets and emotional distractors, where spontaneous prioritization of emotional stimuli leads to suppression of competing perceptual representations potentially linked to an overlapping point in time and space. PMID:23162497

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

    PubMed

    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.

  6. Attack and improvements of fair quantum blind signature schemes

    NASA Astrophysics Data System (ADS)

    Zou, Xiangfu; Qiu, Daowen

    2013-06-01

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

  7. Parameter estimation for blind and non-blind deblurring using residual whiteness measures.

    PubMed

    Almeida, Mariana S C; Figueiredo, Mario A T

    2013-07-01

    Image deblurring (ID) is an ill-posed problem typically addressed by using regularization, or prior knowledge, on the unknown image (and also on the blur operator, in the blind case). ID is often formulated as an optimization problem, where the objective function includes a data term encouraging the estimated image (and blur, in blind ID) to explain the observed data well (typically, the squared norm of a residual) plus a regularizer that penalizes solutions deemed undesirable. The performance of this approach depends critically (among other things) on the relative weight of the regularizer (the regularization parameter) and on the number of iterations of the algorithm used to address the optimization problem. In this paper, we propose new criteria for adjusting the regularization parameter and/or the number of iterations of ID algorithms. The rationale is that if the recovered image (and blur, in blind ID) is well estimated, the residual image is spectrally white; contrarily, a poorly deblurred image typically exhibits structured artifacts (e.g., ringing, oversmoothness), yielding residuals that are not spectrally white. The proposed criterion is particularly well suited to a recent blind ID algorithm that uses continuation, i.e., slowly decreases the regularization parameter along the iterations; in this case, choosing this parameter and deciding when to stop are one and the same thing. Our experiments show that the proposed whiteness-based criteria yield improvements in SNR, on average, only 0.15 dB below those obtained by (clairvoyantly) stopping the algorithm at the best SNR. We also illustrate the proposed criteria on non-blind ID, reporting results that are competitive with state-of-the-art criteria (such as Monte Carlo-based GSURE and projected SURE), which, however, are not applicable for blind ID.

  8. PARENT Quick Blind Round-Robin Test Report

    SciTech Connect

    Braatz, Brett G.; Heasler, Patrick G.; Meyer, Ryan M.

    2014-09-30

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

  9. Reflective insulating blinds for windows and the like

    DOEpatents

    Barnes, Paul R.; Shapira, Hanna B.

    1981-01-01

    Energy-conserving window blinds are provided. The blinds are fabricated from coupled and adjustable slats, each slat having an insulation layer and a reflective surface to face outwardly when the blinds are closed. A range of desired light and air transmission may be selected with the reflective surfaces of the slats adapted to direct sunlight upward toward the ceiling when the blinds are open. When the blinds are closed, the insulation of the slats reduces the heat loss or gain produced by the windows. If desired, the reflective surfaces of the slats may be concave. The edges of the slats are designed to seal against adjacent slats when the blinds are closed to ensure minimum air flow between slats.

  10. Reflective insulating blinds for windows and the like

    DOEpatents

    Barnes, P.R.; Shapira, H.B.

    1979-12-07

    Energy-conserving window blinds are provided. The blinds are fabricated from coupled and adjustable slats, each slat having an insulation layer and a reflective surface to face outwardly when the blinds are closed. A range of desired light and air transmission may be selected with the reflective surfaces of the slats adapted to direct sunlight upward toward the ceiling when the blinds are open. When the blinds are closed, the insulation of the slats reduces the heat loss or gain produced by the windows. If desired, the reflective surfaces of the slats may be concave. The edges of the slats are designed to seal against adjacent slats when the blinds are closed to ensure minimum air flow between slats.

  11. No training blind image quality assessment

    NASA Astrophysics Data System (ADS)

    Chu, Ying; Mou, Xuanqin; Ji, Zhen

    2014-03-01

    State of the art blind image quality assessment (IQA) methods generally extract perceptual features from the training images, and send them into support vector machine (SVM) to learn the regression model, which could be used to further predict the quality scores of the testing images. However, these methods need complicated training and learning, and the evaluation results are sensitive to image contents and learning strategies. In this paper, two novel blind IQA metrics without training and learning are firstly proposed. The new methods extract perceptual features, i.e., the shape consistency of conditional histograms, from the joint histograms of neighboring divisive normalization transform coefficients of distorted images, and then compare the length attribute of the extracted features with that of the reference images and degraded images in the LIVE database. For the first method, a cluster center is found in the feature attribute space of the natural reference images, and the distance between the feature attribute of the distorted image and the cluster center is adopted as the quality label. The second method utilizes the feature attributes and subjective scores of all the images in the LIVE database to construct a dictionary, and the final quality score is calculated by interpolating the subjective scores of nearby words in the dictionary. Unlike the traditional SVM based blind IQA methods, the proposed metrics have explicit expressions, which reflect the relationships of the perceptual features and the image quality well. Experiment results in the publicly available databases such as LIVE, CSIQ and TID2008 had shown the effectiveness of the proposed methods, and the performances are fairly acceptable.

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

    PubMed

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

    2011-06-01

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

  13. Change Blindness in Information Visualization: a Case Study

    SciTech Connect

    Nowell, Lucy T.; Hetzler, Elizabeth G.; Tanasse, Ted E.

    2001-08-20

    Change blindness occurs when people do not notice changes in visible elements of a scene. In using an information visualization system to compare document collection subsets partitioned by their time-stamps, change blindness makes it impossible for users to recognize even very major changes, let alone minor ones. We describe theories from cognitive science that account for the change blindness phenomenon, as well as solutions developed for two visual analysis tools, the SPIRE Galaxies visualization and the SPIRE ThemeView?.

  14. Sixth blind test of organic crystal-structure prediction methods.

    PubMed

    Groom, Colin R; Reilly, Anthony M

    2014-08-01

    Over the past 15 years progress in predicting crystal structures of small organic molecules has been charted by a series of blind tests hosted by the Cambridge Crystallographic Data Centre. This letter announces a sixth blind test to take place between September 2014 and August 2015, giving details of the target systems and the revised procedure. We hope that as many methods as possible will be assessed and benchmarked in this new blind test.

  15. Extrapontine myelinolysis resulting in transient cortical blindness.

    PubMed

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

    2010-02-01

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

  16. Polarimeter Blind Deconvolution Using Image Diversity

    DTIC Science & Technology

    2007-09-01

    Dainty. “Iterative blind deconvolution method and its applications”. Optics Letters, 13(7):547–549, July 1988. 2. Bäck, Thomas, David B. Fogel , and...Fienup, J. R. “Phase Retrieval Algorithms: A Comparison”. Applied Optics, 21(15):2758–2769, 1982. 9. Fiete, Robert D. and Theodore Tantalo...New York, NY 10158-0012, 2000. 15. Goodman, Joseph W. Introduction to Fourier Optics. Roberts & Company Pub- lishers, 4950 S. Yosemite Street, F2 #197

  17. Psychiatric and behavioral correlates of factitious blindness.

    PubMed

    Feldman, Marc D; Eisendrath, Stuart J; Tyerman, Mike

    2008-01-01

    In factitious disorder, an individual feigns, exaggerates, or actually self-induces physical or psychiatric illness to achieve ends such as mobilizing care and concern, ventilating aggression, diminishing guilty feelings, or gratifying dependency wishes. We present 2 new cases of factitious binocular blindness, which has rarely been reported but readily illustrates the dramatic range of factitious illness behaviors. Psychiatric and behavioral correlates culled from these cases include extravagant claims about the impairment and ludicrous claims for nonvisual sensory abilities. These patients typically refuse psychiatric care, but earlier detection can help abort the illness deceptions and forestall iatrogenic complications.

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

    ERIC Educational Resources Information Center

    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…

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

    ERIC Educational Resources Information Center

    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…

  20. Causes of blindness among students in blind school institutions in a developing country.

    PubMed Central

    Chirambo, M C; Benezra, D

    1976-01-01

    Out of 270 students in 17 blind school institutions in Malawi 73 per cent were blind before the age of three. The most common cause for the blindness was ocular infection (75-2 per cent). Meales, as a single cause, was responsible for 43-7 per cent of the cases and smallpox for 5-2 per cent. Bacterial infections were incriminated in 26-3 per cent of the cases. Most of these had received traditional medicine during the acute phase of the disease. Hereditary factors as causes of blindness were found in 7-8 per cent of the cases. These included congenital cataracts (2-6 per cent), optic atorphy of unknown origin (3-0 per cent), microphthalmos (1-5 per cent), and macular degeneration (0-7 per cent). Careful ophthalmological examination showed that in 37 cases an intervention could be attempted in order to improve the vision. In the 11 most favourable cases this was attempted, with the result that nine cases gained a useful vision of 4/60 to 6/18 in the better eye. PMID:990240

  1. Causes of blindness among students in blind school institutions in a developing country.

    PubMed

    Chirambo, M C; Benezra, D

    1976-09-01

    Out of 270 students in 17 blind school institutions in Malawi 73 per cent were blind before the age of three. The most common cause for the blindness was ocular infection (75-2 per cent). Meales, as a single cause, was responsible for 43-7 per cent of the cases and smallpox for 5-2 per cent. Bacterial infections were incriminated in 26-3 per cent of the cases. Most of these had received traditional medicine during the acute phase of the disease. Hereditary factors as causes of blindness were found in 7-8 per cent of the cases. These included congenital cataracts (2-6 per cent), optic atorphy of unknown origin (3-0 per cent), microphthalmos (1-5 per cent), and macular degeneration (0-7 per cent). Careful ophthalmological examination showed that in 37 cases an intervention could be attempted in order to improve the vision. In the 11 most favourable cases this was attempted, with the result that nine cases gained a useful vision of 4/60 to 6/18 in the better eye.

  2. [Change to "prevention of the avoidable blindness and visual impairment" from "prevention of blindness"].

    PubMed

    Zhao, Jialiang

    2015-07-01

    The formulation on the eye health by WHO had an obvious change in recent years. Before 2006, WHO and WHA solutions clearly put forward the prevention of blindness. After 2006, WHO and WHA solutions on the eye health emphasized the elimination of the avoidable blindness and visual impairment. This change extends the scope of eye health, reflects the important progress on the global eye health, and also reflects the social progress and the increase to the need on eye health by the public. This change conforms to the actual situation in China. It is necessary to adopt elimination of the avoidable blindness and visual impairment as the priorities in eye health in making the 13th national plan of blindness prevention. This change is not merely a matter of wording, but also a great change in the working content in eye health. The change demonstrates the deep development on the eye health, and may benefit more people and promote the further development of eye health and ophthalmology in China.

  3. Accuracy assessment of blind and semi-blind restoration methods for hyperspectral images

    NASA Astrophysics Data System (ADS)

    Zhang, Mo; Vozel, Benoit; Chehdi, Kacem; Uss, Mykhail; Abramov, Sergey; Lukin, Vladimir

    2016-10-01

    Hyperspectral images acquired by remote sensing systems are generally degraded by noise and can be sometimes more severely degraded by blur. When no knowledge is available about the degradations present or the original image, blind restoration methods must be considered. Otherwise, when a partial information is needed, semi-blind restoration methods can be considered. Numerous semi-blind and quite advanced methods are available in the literature. So to get better insights and feedback on the applicability and potential efficiency of a representative set of four semi-blind methods recently proposed, we have performed a comparative study of these methods in objective terms of blur filter and original image error estimation accuracy. In particular, we have paid special attention to the accurate recovering in the spectral dimension of original spectral signatures. We have analyzed peculiarities and factors restricting the applicability of these methods. Our tests are performed on a synthetic hyperspectral image, degraded with various synthetic blurs (out-of-focus, gaussian, motion) and with signal independent noise of typical levels such as those encountered in real hyperspectral images. This synthetic image has been built from various samples from classified areas of a real-life hyperspectral image, in order to benefit from realistic reference spectral signatures to recover after synthetic degradation. Conclusions, practical recommendations and perspectives are drawn from the results experimentally obtained.

  4. De-Institutionalizing for the Blind: Life Learning Center for the Blind Retarded, Boston

    ERIC Educational Resources Information Center

    Stephens, Suzanne

    1978-01-01

    A projected learning center in an urban area will be a transitional home, part of an evolving effort to "de-institutionalize" the living environment of the blind and train them to become self-sufficient enough to lead normal lives. (Author/MLF)

  5. 66. CORBELS, BLIND ARCHES & SHIELDS, COMMONS EAST WALL, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    66. CORBELS, BLIND ARCHES & SHIELDS, COMMONS EAST WALL, LOOKING EAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  6. Change Blindness in Information Visualization: A Case Study

    SciTech Connect

    Nowell, Lucille T.; Hetzler, Elizabeth G.; Tanasse, Theodore E.

    2001-08-20

    AbstractChange blindness occurs when people do not notice changes in visible elements of a scene. If people use an infor-mation visualization system to compare document collec-tion subsets partitioned by their time-stamps, change blind-ness makes it impossible for them to recognize even very major changes, let alone minor ones. We describe theories from cognitive science that account for the change blindness phenomenon, as well as solutions de-veloped for two visual analysis tools, a dot plot (SPIRE Galaxies) and landscape (ThemeView?) visualizations.

  7. Congenital stationary night blindness presenting as Leber's congenital amaurosis.

    PubMed

    Weleber, R G; Tongue, A C

    1987-03-01

    Two siblings with autosomal-recessive congenital stationary night blindness were clinically blind in infancy. Both had markedly abnormal electroretinograms that, in the first child, led consultants at two university centers to make the diagnosis of Leber's congenital amaurosis. The patients had intermittent nystagmus and esotropia, but good photopic vision developed eventually. Scotopic vision was clearly defective in each child. Refractive error in both patients was close to emetropic in early infancy but became myopic by 1 year of age. Congenital stationary night blindness must be considered in the differential diagnosis of the blind infant.

  8. [The art of communication in the fingertips. The blind person].

    PubMed

    Freitag Pagliuca, L M

    1996-04-01

    The study analyses the communication process and its peculiarities related to a non verbal communication with blind people. The perceptive answers of the blind people were observed on an Exposition of Plastic Arts for Blind people. The purpose of using this communication language was to contribute to create education methods to these clientele. The methodology included observation, photographic record, video and personal comments. We conclude that the plastic arts are accessible to the blind by touch and give contributions to create materials about health education using the touch. It helps the apprehension of the whole prevailing the figurative related to the aural perception.

  9. Enhanced Chemosensory Detection of Negative Emotions in Congenital Blindness

    PubMed Central

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

    2015-01-01

    It is generally acknowledged that congenitally blind individuals develop superior sensory abilities in order to compensate for their lack of vision. Substantial research has been done on somatosensory and auditory sensory information processing of the blind. However, relatively little information is available about compensatory plasticity in the olfactory domain. Although previous studies indicate that blind individuals have superior olfactory abilities, no studies so far have investigated their sense of smell in relation to social and affective communication. The current study compares congenitally blind and normal sighted individuals in their ability to discriminate and identify emotions from body odours. A group of 14 congenitally blind and 14 age- and sex-matched sighted control subjects participated in the study. We compared participants' abilities to detect and identify by smelling sweat from donors who had been watching excerpts from emotional movies showing amusement, fear, disgust, or sexual arousal. Our results show that congenitally blind subjects outperformed sighted controls in identifying fear from male donors. In addition, there was a strong tendency that blind individuals were also better in detecting disgust. Our findings reveal that congenitally blind individuals are better at identifying ecologically important emotions and provide new insights into the mechanisms of social and affective communication in blindness. PMID:25878902

  10. Enhanced chemosensory detection of negative emotions in congenital blindness.

    PubMed

    Iversen, Katrine D; Ptito, Maurice; Møller, Per; Kupers, Ron

    2015-01-01

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

  11. Fuzzy-based simulation of real color blindness.

    PubMed

    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.

  12. The relationship between sustained inattentional blindness and working memory capacity.

    PubMed

    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.

  13. 20 CFR 416.931 - The meaning of presumptive disability or presumptive blindness.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 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...

  14. 20 CFR 404.1581 - Meaning of blindness as defined in the law.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 2 2012-04-01 2012-04-01 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...

  15. 20 CFR 404.1581 - Meaning of blindness as defined in the law.

    Code of Federal Regulations, 2010 CFR

    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...

  16. 20 CFR 404.1581 - Meaning of blindness as defined in the law.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 2 2014-04-01 2014-04-01 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...

  17. 20 CFR 404.1582 - A period of disability based on blindness.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 2 2014-04-01 2014-04-01 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...

  18. 20 CFR 416.931 - The meaning of presumptive disability or presumptive blindness.

    Code of Federal Regulations, 2010 CFR

    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...

  19. 20 CFR 416.931 - The meaning of presumptive disability or presumptive blindness.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 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...

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

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 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...

  1. 20 CFR 404.1581 - Meaning of blindness as defined in the law.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 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...

  2. 20 CFR 404.1582 - A period of disability based on blindness.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 2 2013-04-01 2013-04-01 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...

  3. 20 CFR 404.1582 - A period of disability based on blindness.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 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...

  4. 20 CFR 404.1582 - A period of disability based on blindness.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 2 2012-04-01 2012-04-01 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...

  5. 20 CFR 416.931 - The meaning of presumptive disability or presumptive blindness.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 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...

  6. 20 CFR 404.1582 - A period of disability based on blindness.

    Code of Federal Regulations, 2010 CFR

    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...

  7. Blind equalization with criterion with memory nonlinearity

    NASA Astrophysics Data System (ADS)

    Chen, Yuanjie; Nikias, Chrysostomos L.; Proakis, John G.

    1992-06-01

    Blind equalization methods usually combat the linear distortion caused by a nonideal channel via a transversal filter, without resorting to the a priori known training sequences. We introduce a new criterion with memory nonlinearity (CRIMNO) for the blind equalization problem. The basic idea of this criterion is to augment the Godard [or constant modulus algorithm (CMA)] cost function with additional terms that penalize the autocorrelations of the equalizer outputs. Several variations of the CRIMNO algorithms are derived, with the variations dependent on (1) whether the empirical averages or the single point estimates are used to approximate the expectations, (2) whether the recent or the delayed equalizer coefficients are used, and (3) whether the weights applied to the autocorrelation terms are fixed or are allowed to adapt. Simulation experiments show that the CRIMNO algorithm, and especially its adaptive weight version, exhibits faster convergence speed than the Godard (or CMA) algorithm. Extensions of the CRIMNO criterion to accommodate the case of correlated inputs to the channel are also presented.

  8. Social Sciences for the Prevention of Blindness

    PubMed Central

    2015-01-01

    Organizations working for the elimination of Chlamydia-triggered blindness (trachoma) follow the WHO SAFE strategy (surgery for trichiasis, antibiotics, face washing and environmental changes) with the aim to achieve a minimum of 80% of children with clean faces in endemic communities, mass treatment covering the whole district with trachoma rates of 10% or more and surveillance plans. Trachoma recurrence that is common after implementing the SAFE strategy 3, 5 or even 7 times evidence that the cognitive processes requiring assimilation and integration of knowledge did not register with parents, caretakers and children. Moreover, repeated awareness campaigns to improve hygiene did not systematically produce irreversible changes of behavior in neglected populations. In view of this evidence, the rational behind mass drug administration as the mainstay of preventable blindness elimination demands a wider scope than simple mathematical models. The reluctance to see disappointing outcomes that leads to repeated interventions may suggest from a sociologic point of view that the strategies are products of those evaluating the activities of those who fund them and vice versa. A similar articulation emerges for reciprocal interactions between researchers and those judging the pertinence and quality of their work. So far, the lack of autocritic elimination strategy approaches may expose inbred circles that did not properly grasp the fact that antibiotics, trichiasis surgery and education limited to improvement of hygiene are inefficient if not associated with long-term basic educational actions in schools. PMID:26161032

  9. Shuffling your way out of change blindness

    PubMed Central

    Josephs, Emilie; Drew, Trafton; Wolfe, Jeremy

    2015-01-01

    Change detection is typically discussed in the literature as a two-state phenomenon. Small differences between otherwise identical images are easy to detect when the images are superimposed in space and alternated in time (“shuffled”). However, change blindness results from any disruption that prevents the critical change from generating the sole salient transient. Here we show that different presentation strategies produce different degrees of change blindness for the same change. Specifically, shuffling the images supports faster change detection than viewing the same two images side-by-side, even when the images contain a number of distracting differences. In Experiment 1, pairs of photographs having a 50% chance of containing a difference were viewed either in alternation, in a “Shuffle” condition, or simultaneously, in a “Side-by-Side” condition. Change detection was about 6 seconds faster when the images were viewed in the “Shuffle” mode. In Experiment 2, we presented two images that were slightly laterally shifted relative to each other (0 – 48 pixels). The RT benefit for the Shuffle viewing mode was very strong when the relative shift was small, to insignificant when there was a large difference between the two images. However, at large shifts, Shuffle maintained an accuracy advantage. It seems that changes are easier to detect when comparing images in a Shuffle condition rather than Side-by-Side. This has important implications for real world tasks like radiology where detection of change is critical. PMID:26106062

  10. Emergence of blind areas in information spreading.

    PubMed

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

    2014-01-01

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

  11. An artistic exploration of inattention blindness.

    PubMed

    Levy, Ellen K

    2011-01-01

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

  12. Mobility aid for blind figure skaters

    NASA Astrophysics Data System (ADS)

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

    2007-11-01

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

  13. Blind image quality assessment via deep learning.

    PubMed

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

    2015-06-01

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

  14. An investigation of the Venetian blind effect.

    PubMed

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

    2011-01-01

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

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

    ERIC Educational Resources Information Center

    Gordon-Salant, Sandra; Friedman, Sarah A.

    2011-01-01

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

  16. 10 CFR 26.168 - Blind performance testing.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Laboratories Certified by the Department of Health... blind performance test samples to the HHS-certified laboratory. (1) During the initial 90-day period of... licensee or other entity shall submit blind performance test samples to each HHS-certified laboratory...

  17. Serving the Deaf-Blind Population: Planning for 1980.

    ERIC Educational Resources Information Center

    Brewer, Garry D.; Kakalik, James S.

    Discussed in the report on planning for services to deaf-blind persons are the impact of the 1963-65 rubella epidemic on service delivery, the need for service system information and control, prevention of rubella as a cost-effective alternative to after care, estimates of the size of the 1980 deaf-blind population, and the projected (1980)cost of…

  18. Cortical blindness in a child with acute glomerulonephritis.

    PubMed

    Kaarthigeyan, K; Vijayalakshmi, A M

    2012-01-01

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

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

    ERIC Educational Resources Information Center

    Torrie, Carolyn

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

  20. Rehabilitation Technology for the Blind in the United States.

    ERIC Educational Resources Information Center

    Jacobson, William H.

    Research in the United States and abroad has led to advances in rehabilitation technology that enables blind and visually impaired persons to compete with sighted persons for employment. Relatively inexpensive devices such as pocket calculators, transistor radios, cassette recorders, and digital watches have become aids for the blind; some…

  1. Blind Rage: An Open Letter to Helen Keller

    ERIC Educational Resources Information Center

    Kleege, Georgina

    2007-01-01

    In a letter addressed to Helen Keller, the author discusses the frustrations of being blind in the modern-day world. She reflects on the seeming pettiness of her complaints next to the difficulties Keller would have faced, especially given all of the new technologies and accommodations available to the blind. She wonders how Keller dealt with her…

  2. Methods for Facilitating the Blind Landing of Airplanes

    NASA Technical Reports Server (NTRS)

    Gloeckner, M Heinrich

    1932-01-01

    Since the introduction of blind flying, the accomplishment of blind landing on prepared fields has become one of the most pressing problems, and many attempts are being made to solve it. The methods employed, in so far as they have been published, are summarized in this report.

  3. AODA Training Experiences of Blindness and Visual Impairment Professionals

    ERIC Educational Resources Information Center

    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,…

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

    ERIC Educational Resources Information Center

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

    2012-01-01

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

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

    PubMed

    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.

  6. 38 CFR 17.154 - Equipment for blind veterans.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Equipment for blind veterans. 17.154 Section 17.154 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS MEDICAL Prosthetic, Sensory, and Rehabilitative Aids § 17.154 Equipment for blind veterans. VA may...

  7. 38 CFR 17.154 - Equipment for blind veterans.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Equipment for blind veterans. 17.154 Section 17.154 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS MEDICAL Prosthetic, Sensory, and Rehabilitative Aids § 17.154 Equipment for blind veterans. VA may...

  8. What Can We Learn about Pictures from the Blind?.

    ERIC Educational Resources Information Center

    Kennedy, John M.

    1983-01-01

    A series of studies on tangible pictures and their application to blind persons are reviewed and possible explanations for the suggestion of depth offered by outline drawings are discussed. Findings from ancient cave and rock art, together with drawings made by blind children and adults suggest that outline drawings contain some elements that are…

  9. Identity and Development: Lessons Learned from a Blind Child

    ERIC Educational Resources Information Center

    Junefelt, Karin

    2004-01-01

    This article uses an analysis of speech to qualitatively examine the relationship between a blind child and his environment, his use of semiotic signs, and his identity development. A brief overview of development in blind children is followed by a case study. The theoretical construct of this article, which is interactionism, is infused into the…

  10. Toilet Habits: Suggestions for Training a Child Who Is Blind.

    ERIC Educational Resources Information Center

    Moor, Pauline M.

    Intended for parents, the pamphlet provides suggestions for toilet training a blind child. Among the 12 tips presented are to establish a regular and convenient toileting schedule, provide a comfortable toilet arrangement, and give the child something to play with. Common problems in toilet training blind children are reported as fear of sitting…

  11. Spatial Orientation and Congenital Blindness: A Neuropsychological Approach.

    ERIC Educational Resources Information Center

    Stuart, I.

    1995-01-01

    Tests of a neuropsychological model for spatial orientation in the absence of vision were developed and administered to 31 children with congenital blindness. Results support the neuropsychological model and indicate that some congenitally blind subjects had focal brain damage, sufficient to impair their capacity to be accurately oriented in…

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

    ERIC Educational Resources Information Center

    Silverrain, Ann

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

  13. Blind Childrens Center Annual Report, 2008-2009

    ERIC Educational Resources Information Center

    Blind Childrens Center, 2009

    2009-01-01

    When entering the Blind Childrens Center (BCC), what a person might not realize is that four of the five visually impaired children in a classroom share the same diagnosis of Optic Nerve Hypoplasia (OHN). ONH is the leading cause of blindness and visual impairment in young children. It is important that these children participate in an inclusive…

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

    ERIC Educational Resources Information Center

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

    2011-01-01

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

  15. Organisation of Recreation for the Blind in the USSR.

    ERIC Educational Resources Information Center

    Kulicheva, N.

    The booklet contains a brief description of recreation under the auspices of the All-Russia Society for the Blind in the Union of Soviet Socialist Republics and a number of photographs illustrating recreational activities. It is noted that approximately 24,000 blind persons participate in recreational activities located in club rooms near their…

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

    ERIC Educational Resources Information Center

    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…

  17. Deaf-Blind Perspectives. Volume 3, 1995-1996.

    ERIC Educational Resources Information Center

    Deaf-Blind Perspectives, 1996

    1996-01-01

    These three newsletter issues present feature articles and resources on individuals with deaf-blindness. The following articles are included: (1) "Current Status for Reauthorization of IDEA" (Joseph McNulty); (2) "Utah Enhances Services for Children Who Are Deaf-Blind" (Paddi Henderson and John Killoran); (3) "Families and…

  18. The Use of Traffic Sounds by Blind Pedestrians.

    ERIC Educational Resources Information Center

    Chew, Stephen L.

    A series of experiments were conducted to study variables affecting the alignment of blind pedestrians at street intersections. In the first two studies blindfolded sighted students, serving as adventitiously blind people undergoing mobility training, learned one of three strategies: no concrete strategy, tracking, and tracking and compensation.…

  19. Teaching the Blind to Read and Write Chinese

    ERIC Educational Resources Information Center

    Roy, Gilbert W.

    1974-01-01

    A technique is described for teaching the blind to read and write Chinese characters through use of raised acrylic writing and the production of a concave impression with pencil or stylus. Other methods for teaching blind students to read are mentioned. (RM)

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

    ERIC Educational Resources Information Center

    Kane, Shaun K.

    2011-01-01

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

  1. 76 FR 58412 - Relay Services for Deaf-Blind Individuals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-21

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

  2. 77 FR 42187 - Relay Services for Deaf-Blind Individuals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-18

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

  3. 77 FR 20553 - Relay Services for Deaf-Blind Individuals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-05

    ... COMMISSION 47 CFR Part 64 Relay Services for Deaf-Blind Individuals AGENCY: Federal Communications Commission... Relay Services for Deaf-Blind Individuals, Report and Order, document FCC 11-56, published at 76 FR... Commission to allocate up to $10 million annually from the Interstate Telecommunications Relay Services...

  4. Social Comparison of Ability in Blind Children and Adolescents.

    ERIC Educational Resources Information Center

    Morin, Stephen F.; Jones, Reginald L.

    Forty-five blind, school aged subjects (aged 6-18 years) were questioned to determine the influence of age on the choice of the blind as a reference group for social comparison of abilities. To assess the direction of social comparison behavior, each subject was presented with a replication of three questions (which differed in the degree to which…

  5. Programs for Deaf-Blind Children and Adults.

    ERIC Educational Resources Information Center

    American Annals of the Deaf, 1997

    1997-01-01

    Lists programs for children and youth with deaf-blindness, Helen Keller Centers for youth and adults with deafness that provide extensive evaluative and rehabilitative services, and programs for training teachers of students with deaf-blindness. Programs are listed by state. (CR)

  6. Educational Opportunities for Blind Children in the Developing World.

    ERIC Educational Resources Information Center

    Winkley, W.

    1989-01-01

    The educational needs of blind youth in developing countries are beginning to be met with training programs offered by such agencies as Helen Keller International of the United States, the Christoffel Blindenmission of West Germany, and the Royal Commonwealth Society of the Blind of the United Kingdom. (Author/DB)

  7. A Weak Quantum Blind Signature with Entanglement Permutation

    NASA Astrophysics Data System (ADS)

    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.

  8. Enhanced sensitivity to echo cues in blind subjects.

    PubMed

    Dufour, André; Després, Olivier; Candas, Victor

    2005-09-01

    Many studies have reported that blind people compensate for their visual deficit by sharpening auditory processes. Here we compare the sensitivity to echo cues between blind and sighted subjects. In the first experiment, the blind subjects were more accurate than the sighted subjects in localizing an object on the basis of echo cues. To ensure that enhanced echolocalization abilities were not only due to the fact that blind individuals are more used to consciously paying attention to echo cues and are more familiar with this kind of tasks than sighted subjects, we tested both groups of subjects in a simple azimuthal localization task of auditory stimuli. In this second experiment, we evaluated the influence of irrelevant echo signals on auditory localization by placing the subjects and the sound sources at different positions in a sound reverberant room. Results revealed that blind subjects exhibit a higher sensitivity to echo signals than sighted subjects.

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

    NASA Astrophysics Data System (ADS)

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

    2016-01-01

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

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

    PubMed

    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.

  11. Solar-blind Raman lidar, phase 2

    NASA Astrophysics Data System (ADS)

    Salik, A.

    1983-06-01

    This document describes the progress of the NADC Atmospheric Lidar Program funded by the Naval Environmental Prediction Research Facility, Monterey, California, under Program Element 62759N, Project F52553. The objective of this effort is to theoretically determine and experimentally verify the ability of a solar-blind lidar system to remotely measure profiles of atmospheric properties critical to naval operations. The properties chosen for investigation are water vapor concentration, temperature and transmission; with the acquisition of water vapor profiles as the primary goal. The theoretical feasibility studies have been thoroughly documented via publication in a professional journal, a technical report and a text on atmospheric water vapor. In addition, experimental results using a KrF excimer laser were presented at the winter 1983 topical meeting of the Optical Society of America. These results are presented in this document.

  12. Visual and phonological codes in repetition blindness.

    PubMed

    Bavelier, D; Potter, M C

    1992-02-01

    Repetition blindness (RB) is the inability to detect or recall a repeated word in rapid serial visual presentation. The role of visual versus phonological (name) similarity in RB was examined. RB was found for single letters, whether printed in the same or different cases, and for single digits, whether represented verbally (nine), as arabic numerals (9), or in a mixture of the 2 formats. Hence, visual similarity is not necessary to produce RB. RB was obtained between homophonic pairs (won/one), showing that phonological similarity is sufficient to produce RB, although visual identity also contributes to RB. It is proposed that RB results when the codes used for initial registration of the targets in short-term memory are similar. This initial code may be predominantly visual or predominantly phonological.

  13. The penny drops: change blindness at fixation.

    PubMed

    Smith, Tim J; Lamont, Peter; Henderson, John M

    2012-01-01

    Our perception of the visual world is fallible. Unattended objects may change without us noticing as long as the change does not capture attention (change blindness). However, it is often assumed that changes to a fixated object will be noticed if it is attended. In this experiment we demonstrate that participants fail to detect a change in identity of a coin during a magic trick even though eyetracking indicates that the coin is tracked by the eyes throughout the trick. The change is subsequently detected when participants are instructed to look for it. These results suggest that during naturalistic viewing, attention can be focused on an object at fixation without including all of its features.

  14. Change blindness and time to consciousness.

    PubMed

    Niedeggen, M; Wichmann, P; Stoerig, P

    2001-11-01

    Detection of changes in a visual scene can be substantially delayed when the original and the modified image are separated by a brief screen flicker. We used this phenomenon of "change blindness" to find when the brain detects the mismatch in relation to when the observer reports it, and whether changes in identity and position are processed similarly. Event-related brain potentials (ERPs) recorded while the subjects searched for the change in alternating series of images showed that the epoch during which they indicated detection was characterized by a marked positivity from 300 to 700 ms. Analysis of data from image presentations preceding the subjects' response revealed a similar but smaller ERP positivity one (identity) or even two (position) epochs before detection. As each epoch lasted 1500 ms, the brain may register a change as early as 3000 ms before the observer.

  15. Visual identity and uncertainty in repetition blindness.

    PubMed

    Brill, Gary A; Glass, Arnold L; Rashid, Hanin; Hussey, Erika

    2008-01-01

    Repetition blindness (RB) was investigated in 6 experiments. In the first 3 experiments participants detected vowel targets in 11-letter sequences. When all letters were uppercase, detection was poorer for same (e.g., AA) than for different (e.g., AO) targets. However, when one target was uppercase and the other lowercase, RB was found only for targets visually identical except for size (e.g., Oo), not for visually different pairs (e.g., Aa). Experiment 4 found RB for visually identical versus different consonant-vowel-consonant words. Experiments 5 and 6 replicated Kanwisher's (1987) experiment in which RB was insensitive to word case but revealed these effects to be artifacts of poor recognition of 5-letter words coupled with a biased guessing strategy. Overall, these experiments found RB only at a low level of visual information processing.

  16. Attending to music decreases inattentional blindness.

    PubMed

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

    2011-12-01

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

  17. Time series for blind biosignal classification model.

    PubMed

    Wong, Derek F; Chao, Lidia S; Zeng, Xiaodong; Vai, Mang-I; Lam, Heng-Leong

    2014-11-01

    Biosignals such as electrocardiograms (ECG), electroencephalograms (EEG), and electromyograms (EMG), are important noninvasive measurements useful for making diagnostic decisions. Recently, considerable research has been conducted in order to potentially automate signal classification for assisting in disease diagnosis. However, the biosignal type (ECG, EEG, EMG or other) needs to be known prior to the classification process. If the given biosignal is of an unknown type, none of the existing methodologies can be utilized. In this paper, a blind biosignal classification model (B(2)SC Model) is proposed in order to identify the source biosignal type automatically, and thus ultimately benefit the diagnostic decision. The approach employs time series algorithms for constructing the model. It uses a dynamic time warping (DTW) algorithm with clustering to discover the similarity between two biosignals, and consequently classifies disease without prior knowledge of the source signal type. The empirical experiments presented in this paper demonstrate the effectiveness of the method as well as the scalability of the approach.

  18. Blind source separation by sparse decomposition

    NASA Astrophysics Data System (ADS)

    Zibulevsky, Michael; Pearlmutter, Barak A.

    2000-04-01

    The blind source separation problem is to extract the underlying source signals from a set of their linear mixtures, where the mixing matrix is unknown. This situation is common, eg in acoustics, radio, and medical signal processing. We exploit the property of the sources to have a sparse representation in a corresponding signal dictionary. Such a dictionary may consist of wavelets, wavelet packets, etc., or be obtained by learning from a given family of signals. Starting from the maximum a posteriori framework, which is applicable to the case of more sources than mixtures, we derive a few other categories of objective functions, which provide faster and more robust computations, when there are an equal number of sources and mixtures. Our experiments with artificial signals and with musical sounds demonstrate significantly better separation than other known techniques.

  19. Blind Signatures in Electronic Voting Systems

    NASA Astrophysics Data System (ADS)

    Kucharczyk, Marcin

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

  20. From blind signal extraction to blind instantaneous signal separation: criteria, algorithms, and stability.

    PubMed

    Cruces-Alvarez, Sergio A; Cichocki, Andrzej; Amari, Shun-ichi

    2004-07-01

    This paper reports a study on the problem of the blind simultaneous extraction of specific groups of independent components from a linear mixture. This paper first presents a general overview and unification of several information theoretic criteria for the extraction of a single independent component. Then, our contribution fills the theoretical gap that exists between extraction and separation by presenting tools that extend these criteria to allow the simultaneous blind extraction of subsets with an arbitrary number of independent components. In addition, we analyze a family of learning algorithms based on Stiefel manifolds and the natural gradient ascent, present the nonlinear optimal activations (score) functions, and provide new or extended local stability conditions. Finally, we illustrate the performance and features of the proposed approach by computer-simulation experiments.

  1. [Light and blindness in ancient Egypt].

    PubMed

    Maria Rosso, Ana

    2010-01-01

    In Ancient Egypt, light and fire, which were closely related to the Sun God Ra, were the sources of life and well-being, while the dark meant danger and death. Similar to death, darkness drops on human beings in deep sleep and they enter a space inhabited by shadows. Dreams were believed to reveal an unknown world, to give the sleeper a glimpse into the future. Vision attracts distant objects and their light, on the other hand, can hurt the eyes like a burning flame. Eyes were the most important organ in Egyptian thought, as they allowed perception of the real world. Their importance has been immortalised in the myth of the Eye of Horus that explains the role of either eye. One represents the moonlight, which disperses the darkness of the night, and the other represents the sunshine, which creates life, and both could also represents the power of human intellect. Blindness, in turn, congenital or disease-related, was considered a divine punishment. A man, thus handicapped, would sink in a state of uncertainty and darkness. To protect the eyes from blindness, people used drops and ointments, which were believed to chase away all kinds of insects and demons that threatened with a variety of eye infections. Egyptian eye doctors or physicians, carried a special kit that contained green chrysocolla and a black kohl makeup, highly appreciated as prophylaxis because they personified Osiris' humours or body fluids. These products were offered to Gods to restore the brightness of divine glance and incite sun and moon to spread their beneficial light.

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

    ERIC Educational Resources Information Center

    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…

  3. Gender-Blind Sexism and Rape Myth Acceptance.

    PubMed

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

    2017-01-01

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

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

    PubMed

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

    2014-01-01

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

  5. Demonstration of measurement-only blind quantum computing

    NASA Astrophysics Data System (ADS)

    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.

  6. Scan blindness in infinite phased arrays of printed dipoles

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

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

  7. Detection of Ionizing Radiation using Solar Blind Air Fluorescence

    DTIC Science & Technology

    2013-06-01

    14 16 Figure 1.2: Geant4 simulation of the solar blind photon flux from 1010 decays of Am241 viewed by a 40 cm diameter detector at a distance of 10 m...discharges and other sources, sufficiently low that it will not interfere with the operation of a solar blind radiological detector ? UNCLASSIFIED iii DSTO...Figures 1.2 through 1.4 show simulated solar blind photon air fluorescence emission from common radiological sources (Am240,Cs137 and Sr90). In each

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

    PubMed

    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.

  9. An oral tactile interface for blind navigation.

    PubMed

    Tang, Hui; Beebe, David J

    2006-03-01

    An oral tactile interface was designed and evaluated to provide directional cues through the tactile channel, which may be utilized by a blind traveler to obtain directional guidance in outdoor navigation. The device was implemented as a mouthpiece with a microfabricated electrotactile display on top for tactile presentation onto the roof of the mouth and a tongue touch keypad at the bottom for simultaneous operation by the tongue. An experimental system allowed a user to communicate with a computer tactilely by using the oral interface. Directional cues were presented to the user as line or arrow patterns with four moving directions (leftward, rightward, forward, and backward). Electrotactile presentation on the roof of the mouth was evaluated in experiments of threshold measurement and identification of directional cues. Experimental results from six human subjects showed that the roof of the mouth required stimulation intensities around 15 V for threshold sensation, and around 25-30 V for comfortable and well-perceived stimulation. Furthermore, identification of leftward or rightward movements was highly accurate while performance on forward or backward moving patterns was mixed and varied considerably among subjects.

  10. Eradicating blinding trachoma: What is working?

    PubMed

    Chaudhry, Imtiaz A

    2010-01-01

    Trachoma remains the leading cause of preventable corneal blindness in developing countries. The disease is contracted in early childhood by repeated infection of the ocular surface by C. trachomatis. Initial clinical manifestation is a follicular conjunctivitis which if not treated on timely basis, may lead to conjunctival and eyelid scarring that may eventually result in corneal scarring and loss of vision. Over the past two decades, a remarkable reduction in the prevalence of active trachoma has occurred due to the World Health Organization's (WHOs) program GET 2020 for the elimination of trachoma with adoption of the SAFE strategy incorporating Surgery, Antibiotic treatment, Facial cleanliness and Environmental hygiene. However, patients who already had infection at young age may present with adnexal-related complications of trachomatous scarring that may cause corneal scarring and visual loss. These patients may present with evidence of trichiasis/entropion as well as eyelid retraction. Lacrimal complications may include nasolacrimal-duct obstruction, dacryocystitis and canaliculitis requiring intervention. In addition to the increased risk for corneal scarring, trichiasis/entropion may further increase the risks for microbial keratitis in patients who may have unrecognized dacryocystitis and canaliculitis. Female patients may have more trachomtous-related complications and may present at an early age. Available evidence indicates that SAFE strategy may be effective and on the right track towards achieving GET 2020 goal for the eradication of trachoma.

  11. The Hadron Blind Ring Imaging Cherenkov Detector

    NASA Astrophysics Data System (ADS)

    Blatnik, Marie; Zajac, Stephanie; Hemmick, Tom

    2013-10-01

    Heavy Ion Collisions in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven Lab have hinted at the existence of a new form of matter at high gluon density, the Color Glass Condensate. High energy electron scattering off of nuclei, focusing on the low-x components of the nuclear wave function, will definitively measure this state of matter. However, when a nucleus contributes a low x parton, the reaction products are highly focused in the electron-going direction and have large momentum in the lab system. High-momentum particle identification is particularly challenging. A particle is identifiable by its mass, but tracking algorithms only yield a particle's momentum based on its track's curvature. The particle's velocity is needed to identify the particle. A ring-imaging Cerenkov detector is being developed for the forward angle particle identification from the technological advancements of PHENIX's Hadron-Blind Detector (HBD), which uses Gas Electron Multipliers (GEMs) and pixelated pad planes to detect Cerenkov photons. The new HBD will focus the Cerenkov photons into a ring to determine the parent particle's velocity. Results from the pad plane simulations, construction tests, and test beam run will be presented.

  12. Consumers' choice-blindness to ingredient information.

    PubMed

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

    2016-11-01

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

  13. [Artificial vision for the human blind].

    PubMed

    Ortigoza-Ayala, Luis Octavio; Ruiz-Huerta, Leopoldo; Caballero-Ruiz, Alberto; Kussul, Ernst

    2009-01-01

    Since 1960 many attempts have been made to develop visual prostheses for the blind; most of the devices based on the production of phosphenes through electrical stimulation with microelectrodes at the retina, optic nerve, lateral geniculate or occipital lobe are incapable to reconstruct a coherent retinotopic map (coordinate match between the image and the visual perception of the patient); furthermore they display important restrictions at the biomaterial level that hinder their final implantation through surgical techniques which at present time offers more risks than benefits to the patient. Considering the new theories about intermodal perception it is possible the acquisition of visual information through other senses; The Micromechanics and Mecatronics Group (GMM) from The Center of Applied Sciences and Technological Development at The National Autonomous University of Mexico by this paper, describes the experimental design and psychophysical data necessary for the construction of a visual sensory substitution prostheses with a vibrotactile system. The vibrotactile mechanism locates different bars over the epidermis in a predetermined way to reproduce a point by point matrix order in a logical sequence of rows and columns that allow the construction of an image with an external device that not require invasive procedures.

  14. Impairment of auditory spatial localization in congenitally blind human subjects.

    PubMed

    Gori, Monica; Sandini, Giulio; Martinoli, Cristina; Burr, David C

    2014-01-01

    Several studies have demonstrated enhanced auditory processing in the blind, suggesting that they compensate their visual impairment in part with greater sensitivity of the other senses. However, several physiological studies show that early visual deprivation can impact negatively on auditory spatial localization. Here we report for the first time severely impaired auditory localization in the congenitally blind: thresholds for spatially bisecting three consecutive, spatially-distributed sound sources were seriously compromised, on average 4.2-fold typical thresholds, and half performing at random. In agreement with previous studies, these subjects showed no deficits on simpler auditory spatial tasks or with auditory temporal bisection, suggesting that the encoding of Euclidean auditory relationships is specifically compromised in the congenitally blind. It points to the importance of visual experience in the construction and calibration of auditory spatial maps, with implications for rehabilitation strategies for the congenitally blind.

  15. CROSS-MODAL PLASTICITY OF TACTILE PERCEPTION IN BLINDNESS

    PubMed Central

    Sathian, K.; Stilla, Randall

    2011-01-01

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

  16. On "A new quantum blind signature with unlinkability"

    NASA Astrophysics Data System (ADS)

    Luo, Yi-Ping; Tsai, Shang-Lun; Hwang, Tzonelih; Kao, Shih-Hung

    2017-04-01

    This article points out a security loophole in Shi et al.'s quantum blind signature scheme. By using the modification attack, a message owner can cheat a signature receiver with a fake message-signature pair without being detected.

  17. Cryptanalysis of a sessional blind signature based on quantum cryptography

    NASA Astrophysics Data System (ADS)

    Su, Qi; Li, Wen-Min

    2014-09-01

    A digital signature is a mathematical scheme for demonstrating the authenticity of a digital message or document. A blind signature is a form of digital signature in which the content of a message is disguised (blinded) before it is signed to protect the privacy of the message from the signatory. For signing quantum messages, some quantum blind signature protocols have been proposed. Recently, Khodambashi et al. (Quantum Inf Process 13:121, 2014) proposed a sessional blind signature based on quantum cryptography. It was claimed that these protocol could guarantee unconditional security. However, after our analysis, we find that the signature protocol will cause the key information leakage in the view of information theory. Taking advantage of loophole, the message sender can succeed in forging the signature without the knowledge of the whole exact key between the verifier and him. To conquer this shortcoming, we construct an improved protocol based on it and the new protocol can resist the key information leakage attacks.

  18. Scientists Spot Gene for Rare Disorder Causing Deafness, Blindness

    MedlinePlus

    ... Health News Related MedlinePlus Health Topics Genes and Gene Therapy Hearing Disorders and Deafness Vision Impairment and Blindness About MedlinePlus Site Map FAQs Customer Support Get email updates Subscribe to ...

  19. DETAIL, EAST ELEVATION. THIS LUNETTE WINDOW POSITIONED IN A BLIND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL, EAST ELEVATION. THIS LUNETTE WINDOW POSITIONED IN A BLIND ARCH ECHOES A SIMILAR TREATMENT OF THE VENETIAN WINDOWS IN THE HOUSE - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

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

    PubMed

    Kreitz, Carina; Furley, Philip; Memmert, Daniel

    2016-01-01

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

  1. Helen Keller Centers for Deaf-Blind Youth and Adults.

    ERIC Educational Resources Information Center

    American Annals of the Deaf, 2003

    2003-01-01

    This listing provides directory information for the national Helen Keller Center and its 10 regional offices. The centers provide extensive evaluative and rehabilitation services to people who are deaf and blind. (CR)

  2. Energy efficient louver and blind. Final technical progress report

    SciTech Connect

    Khajavi, S.

    1996-10-14

    In the month of July, the authors completed the energy testing at Lawrence Berkeley Labs. The final testing was done with blinds in 15 degree position. This is a comfortable blind angle that allows for view of the outside while allowing for natural light to enter the room. It was found that the energy savings are much higher at this angle. At zero degree blind angle the savings were 150 W/sq. meter, in the 15 degree the heat gain is cut by 225 W/sq. meter. During the same period the heat gain in control chamber was 500 W. The heat gain reduction achieved in tests if used in commercial blinds, would result in an energy pay back period or one year and nine months.

  3. 76 FR 65099 - Blind Americans Equality Day, 2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-20

    ..., penning works of literature, lending their voice to music, and inspiring as champions of sport. On Blind... compliance with Section 508 of the Rehabilitation Act. Making electronic and information technology...

  4. Deafness and blindness as a presentation of colorectal meningeal carcinomatosis

    PubMed Central

    Bruce, Beau B.; Tehrani, Mahtab; Newman, Nancy J.; Biousse, Valérie

    2013-01-01

    We present a unique case of a patient with deafness and blindness secondary to carcinomatous meningitis from colorectal adenocarcinoma with accompanying radiologic and pathologic images and a brief review of the relevant literature. PMID:20966893

  5. Experimental Contact Lens to Prevent Glaucoma-Induced Blindness

    MedlinePlus

    ... Articles | Inside Life Science Home Page An Experimental Contact Lens to Prevent Glaucoma-Induced Blindness By Sharon Reynolds Posted January 23, 2014 An experimental contact lens design releases a glaucoma medicine at a ...

  6. Blindness Statistics (Part 1): An Analysis of Operational Options.

    ERIC Educational Resources Information Center

    Schein, Jerome D.; DeSantis, Vito J.

    1986-01-01

    The article compares four means of estimating the size and characteristics of the blind population with respect to accuracy and cost, and recommends a relatively inexpensive method that combines register and survey approaches. (Author/CL)

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

    ERIC Educational Resources Information Center

    Needham, W. E.; And Others

    1992-01-01

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

  8. Thermal blinding of gated detectors in quantum cryptography.

    PubMed

    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.

  9. 76 FR 31261 - Relay Services for Deaf-Blind Individuals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-31

    ... From the Federal Register Online via the Government Publishing Office ] FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 64 Relay Services for Deaf-Blind Individuals AGENCY: Federal Communications Commission. ACTION: Final rule; correction. SUMMARY: The Federal Communications Commission (FCC) is correcting...

  10. The Last Meter: Blind Visual Guidance to a Target

    PubMed Central

    Manduchi, Roberto; Coughlan, James M.

    2014-01-01

    Smartphone apps can use object recognition software to provide information to blind or low vision users about objects in the visual environment. A crucial challenge for these users is aiming the camera properly to take a well-framed picture of the desired target object. We investigate the effects of two fundamental constraints of object recognition – frame rate and camera field of view – on a blind person’s ability to use an object recognition smartphone app. The app was used by 18 blind participants to find visual targets beyond arm’s reach and approach them to within 30 cm. While we expected that a faster frame rate or wider camera field of view should always improve search performance, our experimental results show that in many cases increasing the field of view does not help, and may even hurt, performance. These results have important implications for the design of object recognition systems for blind users. PMID:25426494

  11. 34 CFR 395.33 - Operation of cafeterias by blind vendors.

    Code of Federal Regulations, 2010 CFR

    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...

  12. Clothing-Selection Habits of Teenage Girls Who Are Sighted and Blind.

    ERIC Educational Resources Information Center

    Kaufman, Al

    2000-01-01

    A study that compared the clothing-selection habits of 15 adolescent girls with blindness and 15 sighted girls found parents played a larger role in selecting the clothing for the girls with blindness, girls with blindness wore less makeup and jewelry, and care requirements were more important to girls with blindness. (Contains 12 references.) (CR)

  13. The 2010 National Child Count of Children and Youth Who Are Deaf-Blind

    ERIC Educational Resources Information Center

    National Consortium on Deaf-Blindness, 2011

    2011-01-01

    The National Child Count of Children and Youth who are Deaf-Blind is the first and longest running registry and knowledge base of children who are deaf-blind in the world. It represents a 25-plus year collaborative effort between the National Consortium on Deaf-Blindness (NCDB), its predecessors and each state deaf-blind project throughout the…

  14. The 2008 National Child Count of Children and Youth Who Are Deaf-Blind

    ERIC Educational Resources Information Center

    National Consortium on Deaf-Blindness, 2009

    2009-01-01

    The "National Child Count of Children and Youth who are Deaf-Blind" is the first and longest running registry and knowledge base of children who are deaf-blind in the world. It represents a 25 year collaborative effort between the National Consortium on Deaf-Blindness (NCDB), its predecessors and each state/multi-state deaf-blind project…

  15. 20 CFR 416.984 - If you are statutorily blind and still working.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false If you are statutorily blind and still working. 416.984 Section 416.984 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Blindness § 416.984 If...

  16. 20 CFR 416.903 - Who makes disability and blindness determinations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

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

  17. 20 CFR 416.984 - If you are statutorily blind and still working.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 2 2013-04-01 2013-04-01 false If you are statutorily blind and still working. 416.984 Section 416.984 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Blindness § 416.984 If...

  18. 20 CFR 416.984 - If you are statutorily blind and still working.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false If you are statutorily blind and still working. 416.984 Section 416.984 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Blindness § 416.984 If...

  19. 20 CFR 416.984 - If you are statutorily blind and still working.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false If you are statutorily blind and still working. 416.984 Section 416.984 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Blindness § 416.984 If...

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

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false Who makes disability and blindness... INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Determinations § 416.903 Who makes disability and blindness determinations. (a) State agencies. State agencies make...

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

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 2 2013-04-01 2013-04-01 false Who makes disability and blindness... INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Determinations § 416.903 Who makes disability and blindness determinations. (a) State agencies. State agencies make...

  2. 20 CFR 416.903 - Who makes disability and blindness determinations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false Who makes disability and blindness... INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Determinations § 416.903 Who makes disability and blindness determinations. (a) State agencies. State agencies make...

  3. 20 CFR 416.984 - If you are statutorily blind and still working.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false If you are statutorily blind and still working. 416.984 Section 416.984 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Blindness § 416.984 If...

  4. 20 CFR 416.903 - Who makes disability and blindness determinations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Who makes disability and blindness... INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Determinations § 416.903 Who makes disability and blindness determinations. (a) State agencies. State agencies make...

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

    ERIC Educational Resources Information Center

    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…

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

    ERIC Educational Resources Information Center

    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…

  7. Real-time Blind Separation and Deconvolution of Real-world signals

    DTIC Science & Technology

    2003-01-01

    public release; distribution unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT We present a reallistic and robust implementation of Blind Source...Separation and Blind Deconvolution. The algorithm is developed from the idea of natraul gradient learning, wavlet filtering and denoising , and the...reallistic and robust implementation of Blind Source Separation and Blind Deconvolution. The algorithm is developed from the idea of natraul gradient

  8. Risk factors for maternal night blindness in rural South India

    PubMed Central

    Katz, Joanne; Tielsch, James M.; Thulasiraj, R. D.; Coles, Christian; Sheeladevi, S.; Yanik, Elizabeth L.; Rahmathullah, Lakshmi

    2009-01-01

    Purpose This study aimed to identify risk factors associated with maternal night blindness in rural South India. Methods At delivery, women enrolled in a population-based trial of newborn vitamin A supplementation were asked whether they were night blind at any time during the pregnancy. Multivariate logistic regression was used to identify socioeconomic, demographic, and pregnancy related factors associated with maternal night blindness. Results Women reported night blindness in 687 (5.2%) of 13,171 pregnancies. In a multivariate model, having a concrete roof (Odds Ratio (OR): 0.60, 95% Confidence Interval (CI): 0.47, 0.78), religion other than Hindu (OR: 0.46, 95% CI: 0.27, 0.76), maternal literacy (OR: 0.58, 95% CI: 0.49, 0.69), and maternal age from 25 to 29 years (OR: 0.68, 95%CI: 0.50, 0.93) were associated with a lower risk of night blindness in pregnancy. The odds of night blindness were higher for those leasing rather than owning land (OR: 1.78, 95%CI: 1.08, 2.93), parity 6 or more compared to 0 (OR: 2.11, 95% CI: 1.09, 4.08), and with twin pregnancies (OR: 3.23, 95% CI: 1.93, 5.41). Factors not associated with night blindness in the multivariate model were other markers of socioeconomic status such as electricity in the house, radio and television ownership, type of cooking fuel, and household transportation, and number of children under 5 years of age in the household. Conclusions Maternal night blindness was prevalent in this population. Being pregnant with twins and of higher parity put women at higher risk. Maternal literacy and higher socioeconomic status lowered the risk. PMID:19437315

  9. Transient cortical blindness after thoracic endovascular aneurysm repair.

    PubMed

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

    2011-05-01

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

  10. Does the World Health Organization criterion adequately define glaucoma blindness?

    PubMed Central

    Mokhles, P; Schouten, JSAG; Beckers, HJM; Webers, CAB

    2017-01-01

    Purpose Blindness in glaucoma is difficult to assess with merely the use of the current World Health Organization (WHO) definition (a visual field restricted to 10° in a radius around central fixation), as this criterion does not cover other types of visual field loss that are encountered in clinical practice and also depict blindness. In this study, a 5-point ordinal scale was developed for the assessment of common visual field defect patterns, with the purpose of comparing blindness as outcome to the findings with the WHO criterion when applied to the same visual fields. The scores with the two methods were compared between two ophthalmologists. In addition, the variability between these assessors in assessing the different visual field types was determined. Methods Two glaucoma specialists randomly assessed a sample of 423 visual fields from 77 glaucoma patients, stripped of all indices and masked for all patient variables. They applied the WHO criterion and a 5-point ordinal scale to all visual fields for the probability of blindness. Results The WHO criterion was mostly found applicable and in good agreement for both assessors to visual fields depicting central island of vision or a temporal crescent. The percentage of blindness scores was higher when using the ordinal scale, 21.7% and 19.6% for assessors A and B, respectively, versus 14.4% and 11.3% for the WHO criterion. However, Kappa was lower, 0.71 versus 0.78 for WHO. Conclusions The WHO criterion is strictly applied and shows good agreement between assessors; however, blindness does not always fit this criterion. More visual fields are labeled as blind when a less stringent criterion is used, but this leads to more interobserver variability. A new criterion that describes the extent, location, and depth of visual field defects together with their consequence for the patient’s quality of life is needed for the classification of glaucoma blindness. PMID:28280297

  11. Thalamocortical Connectivity and Microstructural Changes in Congenital and Late Blindness

    PubMed Central

    Dyrby, T. B.; Siebner, H. R.; Lundell, H.; Kupers, 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. To assess the thalamocortical network, we used a clustering method based on the thalamic white matter projections towards predefined cortical regions. Five thalamic clusters were obtained in each group representing their cortical projections. Although we did not find differences in the thalamocortical 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) in occipital and temporal thalamocortical projections in both blind groups that were not captured at the network level. This suggests that plastic microstructural changes have taken place, but not in a degree to be reflected in the tractography-based thalamocortical network. PMID:28386486

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

    PubMed

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

    2012-08-01

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

  13. Prevention of blindness and priorities for the future.

    PubMed Central

    West, S.; Sommer, A.

    2001-01-01

    The impact of visual loss has profound implications for the person affected and society as a whole. The majority of blind people live in developing countries, and generally, their blindness could have been avoided or cured. Given the current predictions that the number of blind people worldwide will roughly double by the year 2020, it is clear that there is no room for complacency. As the world's population increases and as a greater proportion survives into late adulthood, so the number of people with visual loss will inexorably rise. Given the success of programmes in combating the most common causes of blindness (infectious diseases and malnutrition) which generally affect the young, and the projected demographic shift, age-related eye disease will become increasingly prevalent. Effective preventive measures for these diseases can only be established as more is known about their etiology. As the longevity of the world's population increases, the visual requirements at the workplace are also changing. People with low vision may be at a disadvantage in many common activities, and may face unemployment--particularly in technological societies. The definition of blindness needs to be rethought, to ensure that people with "economic" blindness are not forgotten. Efforts should be made to recognize and treat those affected at an early stage, for the benefit of the individual and society. PMID:11285670

  14. Implicit binding of facial features during change blindness.

    PubMed

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

    2014-01-01

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

  15. Implicit Binding of Facial Features During Change Blindness

    PubMed Central

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

    2014-01-01

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

  16. Functional relevance of cross-modal plasticity in blind humans

    NASA Astrophysics Data System (ADS)

    Cohen, Leonardo G.; Celnik, Pablo; Pascual-Leone, Alvaro; Corwell, Brian; Faiz, Lala; Dambrosia, James; Honda, Manabu; Sadato, Norihiro; Gerloff, Christian; Catalá, M. Dolores; Hallett, Mark

    1997-09-01

    Functional imaging studies of people who were blind from an early age have revealed that their primary visual cortex can be activated by Braille reading and other tactile discrimination tasks. Other studies have also shown that visual cortical areas can be activated by somatosensory input in blind subjects but not those with sight. The significance of this cross-modal plasticity is unclear, however, as it is not known whether the visual cortex can process somatosensory information in a functionally relevant way. To address this issue, we used transcranial magnetic stimulation to disrupt the function of different cortical areas in people who were blind from an early age as they identified Braille or embossed Roman letters. Transient stimulation of the occipital (visual) cortex induced errors in both tasks and distorted the tactile perceptions of blind subjects. In contrast, occipital stimulation had no effect on tactile performance in normal-sighted subjects, whereas similar stimulation is known to disrupt their visual performance. We conclude that blindness from an early age can cause the visual cortex to be recruited to a role in somatosensory processing. We propose that this cross-modal plasticity may account in part for the superior tactile perceptual abilities of blind subjects.

  17. Milestones on the road to independence for the blind

    NASA Astrophysics Data System (ADS)

    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?'

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

    PubMed

    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.

  19. RETENTION OF HIGH TACTILE ACUITY THROUGHOUT THE LIFESPAN IN BLINDNESS

    PubMed Central

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

    2009-01-01

    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 re-examined this age dependence with two newly designed tactile-acuity charts requiring 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 in age from 12 to 85 years, 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 lifespan. PMID:19064491

  20. Ivermectin for onchocercal eye disease (river blindness)

    PubMed Central

    Ejere, Henry OD; Schwartz, Ellen; Wormald, Richard; Evans, Jennifer R

    2015-01-01

    Background It is believed that ivermectin (a microfilaricide) could prevent blindness due to onchocerciasis. However, when given to everyone in communities where onchocerciasis is common, the effects of ivermectin on lesions affecting the eye are uncertain and data on whether the drug prevents visual loss are unclear. Objectives The aim of this review was to assess the effectiveness of ivermectin in preventing visual impairment and visual field loss in onchocercal eye disease. The secondary aim was to assess the effects of ivermectin on lesions affecting the eye in onchocerciasis. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2012, Issue 3), MEDLINE (January 1950 to April 2012), EMBASE (January 1980 to April 2012), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 2 April 2012. Selection criteria We included randomised controlled trials with at least one year of follow-up comparing ivermectin with placebo or no treatment. Participants in the trials were people normally resident in endemic onchocercal communities with or without one or more characteristic signs of ocular onchocerciasis. Data collection and analysis Two review authors independently extracted data and assessed trial quality. We contacted study authors for additional information. As trials varied in design and setting, we were unable to perform a meta-analysis. Main results The review included four trials: two small studies (n = 398) in which people with onchocercal infection were given one dose of ivermectin or placebo and followed up for one year; and two larger community-based studies (n = 4941) whereby all individuals in

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

    PubMed Central

    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 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 reflected in

  2. Three Blind Men and the Elephant

    SciTech Connect

    Long, J S

    2007-02-13

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

  3. Congenital abnormalities of the urogenital tract: the clue is in the cord?

    PubMed

    Daoub, Ahmed; Drake, Thomas M

    2014-12-02

    Congenital abnormalities of the female urogenital tract are not uncommon, with an estimated incidence of 2-4% across the female population. Within this population, up to 40% will have associated renal tract abnormalities. A previously well 12-year-old girl presented to the emergency department with abdominal pain, vomiting and a palpable pelvic mass. Ultrasound and MR scans were performed. The imaging revealed a didelphys uterus, an obstructed hemivagina and ipsilateral renal agenesis, characteristic of Herlyn-Werner-Wunderlich syndrome. The patient was noted at birth to have a single umbilical artery, which is associated with an increased risk of congenital abnormalities and useful information for the early identification of abnormalities that have implications for renal function and future fertility.

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

    PubMed Central

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

    2016-01-01

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

  5. Craniocervical postural relations and craniofacial morphology in 30 blind subjects.

    PubMed

    Fjellvang, H; Solow, B

    1986-10-01

    Previous studies have shown that head posture is dependent on vision. The head posture of blind persons therefore can be expected to differ from that of normal subjects. This is of interest in the current analyses of the relation between head posture and craniofacial morphology. The purpose of the present investigation was to describe the posture of the head and cervical column and the craniofacial morphology in a group of blind subjects, and to compare the findings with those previously found in male and female groups of normal subjects. The sample comprised 30 blind subjects--18 men and 12 women, aged 15 to 35 years, all of whom had been without perception of light since birth. The control group comprised 120 male dental students in the age range 22 to 30 years and 51 female dental students in the age range 22 to 27 years. The analysis of head posture showed that the intra-and interindividual variabilities of the craniovertical angles were significantly larger than those of the craniocervical angles in the blind group. The interindividual variabilities of the craniovertical angles were significantly larger in the blind than in the control group, but the variabilities of the craniocervical angles were similar in both groups. Craniovertical relations thus were more variable in the blind subjects, whereas craniocervical relations showed the same variability as normal subjects. On the average, the head was carried in a 4.3 degrees lower position in the neck was 4.5 degrees more forward inclined in the blind group. No differences were found in the position of the head in relation to the cervical column between the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. Comparison between blinded and partially blinded detection of gastric cancer with multidetector CT using surgery and endoscopic submucosal dissection as reference standards.

    PubMed

    Kim, H J; Lee, D H; Ko, Y T

    2010-08-01

    The aim of this study is to compare blinded with partially blinded detection of gastric cancer with multidetector (MD) CT by using surgery and endoscopic submucosal dissection (ESD) as reference standards. 44 patients with gastric cancer underwent MDCT with air as an oral contrast agent. Surgery was performed on 37 patients, ESD on six and surgery after ESD on one. To provide comparison cases of blinded evaluation, 38 MDCT examinations were added for cases where no focal gastric lesion was seen on endoscopy. Two radiologists, blinded to the presence, number and location of the tumours, evaluated axial and axial plus multiplanar reformation (MPR) images of 82 MDCT examinations with or without gastric cancer. For partially blinded evaluation, the same radiologists, blinded to the location and number of tumours, evaluated axial and axial plus MPR images of 44 MDCT examinations of gastric cancer. Differences in assessment were resolved by consensus. 45 gastric cancers were found in surgical and ESD specimens. Detection rates of gastric cancer from axial and axial plus MPR images during blinded evaluation and from axial and axial plus MPR images during partially blinded evaluation were 62% (28/45), 64% (29/45), 64% (29/45) and 71% (32/45), respectively. There was no statistical significance for the comparison between blinded and partially blinded detection rates of gastric cancer. The detection rate of gastric cancer with MDCT during blinded evaluation showed no specific difference compared with the detection rate of gastric cancer with MDCT during partially blinded evaluation.

  7. Serving Deaf-Blind Children. Theme of the International Conference on Deaf-Blind Children (4th, 22-27 August 1971, Perkins School for the Blind).

    ERIC Educational Resources Information Center

    Perkins School for the Blind, Watertown, MA.

    Presented are 30 papers given at a 5-day international conference on serving deaf-blind children. Additionally provided are the conference agenda, a review of the conference, reports of the nominations and resolutions committees, and a list of conference participants. Among the papers are the following titles: "Programs for Non-Verbal Children",…

  8. Blinded by the Light (Artist Concept)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] [figure removed for brevity, see original site] Figure 1: Visible PanelFigure 2: Infrared Panel

    This artist's concept shows what a fiery hot star and its close-knit planetary companion might look close up if viewed in visible (figure 1) and infrared light (figure 2). In visible light, a star shines brilliantly, overwhelming the little light that is reflected by its planet. In infrared, a star is less blinding, and its planet perks up with a fiery glow.

    Astronomers using NASA's Spitzer Space Telescope took advantage of this fact to directly capture the infrared light of two previously detected planets orbiting outside our solar system. Their findings revealed the temperatures and orbits of the planets. Upcoming Spitzer observations using a variety of infrared wavelengths may provide more information about the planets' winds and atmospheric compositions.

    These colors represent real differences between the visible and infrared views of the system. The visible panel shows what our eyes would see if we could witness the system close up. The hot star is yellow because, like our Sun, it is brightest in yellow wavelengths. The warm planet, on the other hand, is brightest in infrared light, which we can't see. Instead, we would see the glimmer of star light that the planet reflects.

    In the infrared panel, the colors reflect what our eyes might see if we could retune them to the invisible, infrared portion of the light spectrum. The hot star is less bright in infrared light than in visible and appears fainter. The warm planet peaks in infrared light, so is shown brighter. Their hues represent relative differences in temperature. Because the star is hotter than the planet, and because hotter objects give off more blue light than red, the star is depicted in blue, and the planet, red.

    The overall look of the planet is inspired by theoretical models of hot, gas giant planets. These 'hot Jupiters' are

  9. The First Rapid Assessment of Avoidable Blindness (RAAB) in Thailand

    PubMed Central

    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

    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. PMID:25502762

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

    PubMed

    Leivada, Evelina; Boeckx, Cedric

    2014-01-01

    The repeatedly noted absence of case-reports of individuals with schizophrenia and congenital/early developed blindness has led several authors to argue that the latter can confer protective effects against the former. In this work, we present a number of relevant case-reports from different syndromes that show comorbidity of congenital and early blindness with schizophrenia. On the basis of these reports, we argue that a distinction between different types of blindness in terms of the origin of the visual deficit, cortical or peripheral, is crucial for understanding the observed patterns of comorbidity. We discuss the genetic underpinnings and the brain structures involved in schizophrenia and blindness, with insights from language processing, laying emphasis on the three structures that particularly stand out: the occipital cortex, the lateral geniculate nucleus (LGN), and the pulvinar. Last, we build on previous literature on the nature of the protective effects in order to offer novel insights into the nature of the protection mechanism from the perspective of the brain structures involved in each type of blindness.

  11. Attenuation of change blindness in children with autism spectrum disorders.

    PubMed

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

    2012-09-01

    Change blindness refers to the difficulty most people find in detecting a difference between two pictures when these are presented successively, with a brief interruption between. Attention at the site of the change is required for detection. A number of studies have investigated change blindness in adults and children with autism spectrum disorders (ASD). Some have produced evidence that people with ASD find changes to social stimuli harder to detect and changes to non-social stimuli easier to detect, relative to comparison participants. However, other studies have produced entirely contradictory findings. There is a need for consistency in methodology to aid understanding of change blindness and attentional processes in ASD. Here, we replicate a change blindness study previously carried out with typically developing (TD) children and adults and with adults with ASD. Results reveal attenuated change blindness for non-social stimuli in children with ASD relative to TD norms. Our results are interpreted, alongside others' findings, as potentially indicative of a complex relationship between different influences on attention over time.

  12. Dual-mode type algorithms for blind equalization

    NASA Astrophysics Data System (ADS)

    Weerackody, Vijitha; Kassam, Saleem A.

    1994-01-01

    Adaptive channel equalization accomplished without resorting to a training sequence is known as blind equalization. The Godard algorithm and the generalized Sato algorithm are two widely referenced algorithms for blind equalization of a QAM system. These algorithms exhibit very slow convergence rates when compared to algorithms employed in conventional data-aided equalization schemes. In order to speed up the convergence process, these algorithms may be switched over to a decision-directed equalization scheme once the error level is reasonably low. We present a scheme which is capable of operating in two modes: blind equalization mode and a mode similar to the decision-directed equalization mode. In this proposed scheme, the dominant mode of operation changes from the blind equalization mode at higher error levels to the mode similar to the decision-directed equalization mode at lower error levels. Manual switch-over to the decision-directed mode from the blind equalization mode, or vice-versa, is not necessary since transitions between the two modes take place smoothly and automatically.

  13. The global elimination of blinding trachoma: progress and promise.

    PubMed

    Kumaresan, Jacob A; Mecaskey, Jeffrey W

    2003-11-01

    Trachoma is the world's leading cause of preventable blindness. It affects approximately 150 million people living in the world's poorest, rural communities and causes an estimated loss of $2.9 billion in productivity annually. In 1985, the Edna McConnell Clark Foundation joined with the World Health Organization to support studies on trachoma epidemiology and control, resulting in the elaboration of the surgery, antibiotics, facial cleanliness and environmental improvement (SAFE) strategy as the basis for the elimination of this blinding disease. Founded in 1998 by the Clark Foundation and Pfizer, Inc., the International Trachoma Initiative (ITI) is the only organization dedicated to eliminating blinding trachoma through support to national control programs. The availability of donated Zithromax (azithromycin) by Pfizer, Inc. has been paramount to the support of the ITI for implementation of SAFE in 10 country programs. The program has made considerable progress in four years. More than seven million individuals have received treatment, resulting in a cumulative reduction of 50% in active disease rates in children. More than 60,000 have also benefited from lid surgery that has halted progression to blindness. Morocco is expecting to attain the elimination of blinding trachoma by 2005. However, the challenges facing the goal of global elimination by 2020 involve a vital program expansion, increased financial and technical support, environmental improvement, and continued advocacy efforts.

  14. Strategic issues in preventing cataract blindness in developing countries.

    PubMed Central

    Ellwein, L. B.; Kupfer, C.

    1995-01-01

    Cataract blindness is a public health problem of major proportions in developing countries. Intracapsular cataract extraction with aphakic spectacles has been the standard surgical technique for restoring sight. Because of image magnification in the operated eye, however, the result in unilaterally blind patients is less than satisfactory. Fortunately, with the availability of low-cost intraocular lenses (IOL) and ophthalmologists trained in extracapsular surgery, it is now practical to intervene successfully in the unilateral case. The need for increased attention on the quality of the visual high prevalence of cataract blindness in developing countries and an increasing cataract incidence due to an aging population require substantial increases in surgical volume. The third issue relates to cost. If significant increases in surgical volume and quality of outcomes are to be realized without an increased need for external funding, service delivery must be made more efficient. The expansion of IOL surgery for unilateral blindness is a favourable trend in ensuring financial sustainability of delivery systems; patients can be operated on while still economically productive and able to pay rather than waiting for bilateral blindness and a less favourable economic and social impact. If the quality, volume, and cost issues are to be successfully addressed, operational and structural changes to eye care delivery systems are necessary. These changes can be effected through training, technology introduction, management of facilities, social marketing, organizational partnerships, and evaluation. With improved understanding of the critical factors in successful models their widespread replication will be facilitated. PMID:8846495

  15. Brain systems mediating voice identity processing in blind humans.

    PubMed

    Hölig, Cordula; Föcker, Julia; Best, Anna; Röder, Brigitte; Büchel, Christian

    2014-09-01

    Blind people rely more on vocal cues when they recognize a person's identity than sighted people. Indeed, a number of studies have reported better voice recognition skills in blind than in sighted adults. The present functional magnetic resonance imaging study investigated changes in the functional organization of neural systems involved in voice identity processing following congenital blindness. A group of congenitally blind individuals and matched sighted control participants were tested in a priming paradigm, in which two voice stimuli (S1, S2) were subsequently presented. The prime (S1) and the target (S2) were either from the same speaker (person-congruent voices) or from two different speakers (person-incongruent voices). Participants had to classify the S2 as either a old or a young person. Person-incongruent voices (S2) compared with person-congruent voices elicited an increased activation in the right anterior fusiform gyrus in congenitally blind individuals but not in matched sighted control participants. In contrast, only matched sighted controls showed a higher activation in response to person-incongruent compared with person-congruent voices (S2) in the right posterior superior temporal sulcus. These results provide evidence for crossmodal plastic changes of the person identification system in the brain after visual deprivation.

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

    PubMed Central

    Leivada, Evelina; Boeckx, Cedric

    2014-01-01

    The repeatedly noted absence of case-reports of individuals with schizophrenia and congenital/early developed blindness has led several authors to argue that the latter can confer protective effects against the former. In this work, we present a number of relevant case-reports from different syndromes that show comorbidity of congenital and early blindness with schizophrenia. On the basis of these reports, we argue that a distinction between different types of blindness in terms of the origin of the visual deficit, cortical or peripheral, is crucial for understanding the observed patterns of comorbidity. We discuss the genetic underpinnings and the brain structures involved in schizophrenia and blindness, with insights from language processing, laying emphasis on the three structures that particularly stand out: the occipital cortex, the lateral geniculate nucleus (LGN), and the pulvinar. Last, we build on previous literature on the nature of the protective effects in order to offer novel insights into the nature of the protection mechanism from the perspective of the brain structures involved in each type of blindness. PMID:25506321

  17. Preferential interactions promote blind cooperation and informed defection.

    PubMed

    Pérez-Escudero, Alfonso; Friedman, Jonathan; Gore, Jeff

    2016-12-06

    It is common sense that costs and benefits should be carefully weighed before deciding on a course of action. However, we often disapprove of people who do so, even when their actual decision benefits us. For example, we prefer people who directly agree to do us a favor over those who agree only after securing enough information to ensure that the favor will not be too costly. Why should we care about how people make their decisions, rather than just focus on the decisions themselves? Current models show that punishment of information gathering can be beneficial because it forces blind decisions, which under some circumstances enhances cooperation. Here we show that aversion to information gathering can be beneficial even in the absence of punishment, due to a different mechanism: preferential interactions with reliable partners. In a diverse population where different people have different-and unknown-preferences, those who seek additional information before agreeing to cooperate reveal that their preferences are close to the point where they would choose not to cooperate. Blind cooperators are therefore more likely to keep cooperating even if conditions change, and aversion to information gathering helps to interact preferentially with them. Conversely, blind defectors are more likely to keep defecting in the future, leading to a preference for informed defectors over blind ones. Both mechanisms-punishment to force blind decisions and preferential interactions-give qualitatively different predictions, which may enable experimental tests to disentangle them in real-world situations.

  18. Neural correlates of virtual route recognition in congenital blindness.

    PubMed

    Kupers, Ron; Chebat, Daniel R; Madsen, Kristoffer H; Paulson, Olaf B; Ptito, Maurice

    2010-07-13

    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 but not blindfolded sighted control subjects activated the parahippocampus and visual cortex during navigation, areas that are recruited during topographical learning and spatial representation in sighted subjects. When the navigation task was performed under full vision in a second group of sighted participants, the activation pattern strongly resembled the one obtained in the blind when using the TDU. This suggests that in the absence of vision, cross-modal plasticity permits the recruitment of the same cortical network used for spatial navigation tasks in sighted subjects.

  19. Morphometric changes of the corpus callosum in congenital blindness.

    PubMed

    Tomaiuolo, Francesco; Campana, Serena; Collins, D Louis; Fonov, Vladimir S; Ricciardi, Emiliano; Sartori, Giuseppe; Pietrini, Pietro; Kupers, Ron; Ptito, Maurice

    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 callosum are in line with the well-described cross-modal functional and structural neuroplastic changes in congenital blindness.

  20. The global problem of blindness and visual dysfunction

    NASA Astrophysics Data System (ADS)

    Lakshminarayanan, Vasudevan

    2012-10-01

    According to World Health Organization statistics there are approximately 285 million people who are blind, have severe low vision, or are near-blind. Of these, 39 million are blind, and 246 million have low vision problems. About 90% of these live in developing countries. The major causes are uncorrected refractive errors (42%), and cataracts (38%). In the US, there are about 6 million people over the age of 65 who have age-related macular degeneration which is the leading cause of blindness. For each decade after age 40, it is found that there is a three-fold increase in the prevalence of blindness and low vision. This paper will address the question of what can we, as optical physicists and engineers, do? There is a need for efficient methods to detect problems, investigate function, provide solutions, and develop rehabilitation devices for the visually impaired. Here I will sketch out the magnitude and variety of the problem, examples and future research directions.